! BERKELEY 
 -IBRARY 
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 TMEN1 
 
DEPARTMENT OF AGRICULTURE. 
 
 VITICULTURAL STATION, RUTHEMLEN, VICTORIA, 
 
 WINE-MAKING IN HOT CLIMATES 
 
 L. R O O 8, 
 
 Director of the (Enological Station of the Herault. 
 
 Translated by 
 RAYMOND DUBOIS, B.Sc. (Paris), 
 
 Diplome de I'Ecole d' Agriculture de Montpellier, Director of the 
 
 Viticultural Station, Victoria ; 
 
 AXD 
 
 W. PERCY WILKINSON, 
 
 Private Assistant to the Government Analyst, Consulting Analyst to the 
 M. and M. Board of Works. 
 
 $B ^uthoritg : 
 
 ROBT. S. BRAIN, GOVERNMENT PRINTER, MELBOURNE. 
 1900. 
 
 10649. 
 
TRANSLATORS' PREFACE. 
 
 Iii presenting this translation of U Industrie Vinicole 
 Meridionale* by Professor L. Roos, to Australian wine- 
 makers, the sole aim of the translators has been to render 
 a thoroughly modern work on wine-making available, 
 of a type of which the necessity has been obvious, and 
 frequently commented on for some years. 
 
 The selection of the present work for translation was 
 guided principally by the fact f that the climate, and 
 conditions of wine-making, in the South of France, for 
 which the book was expressly written, are practically 
 identical with those of Australia. The new methods and 
 innovations in vinification adopted there (as also in 
 California) should be applied here without hesitation, if 
 we are to keep abreast of recent advances, or rather, of 
 our competitors in the export wine trade with Great 
 Britain, on which the future expansion and success of our 
 viticultural industry largely depends. 
 
 We feel convinced, from an intimate knowledge of the 
 actual local conditions of wine-making, that the general 
 and immediate adoption throughout Victoria of the 
 improved methods of vinification so ably advocated by 
 Professor Roos, and already extensively applied in practice 
 in the South of France, Algiers, and California, will 
 prove of the utmost advantage to our wine industry ; 
 
 * Roos, L., V Industrie Vinicole Meridionale, pp. vi. 326. 8vo. Montpellier 
 and Paris. 1898. 
 
 f One of us (R. Dubois) studied for several years under Professor Roos 
 at Montpellier. 
 
 804 
 
and should result in greatly diminishing the quantity ot 
 wine annually passed through the still, and in increasing 
 the production of sound dry wine of good keeping qualities, 
 which will be of higher average market value than hitherto. 
 
 Our earnest hope is that Australian wine-makers will 
 accord Professor Roos' book the serious attention and 
 consideration it merits, as recording the latest definite 
 advances in wine-making in hot climates. 
 
 RAYMOND DUBOIS. 
 
 W. PERCY WILKINSON. 
 
 Viticultural Station, 
 Rutherglen, 15th February, 1900. 
 
WIM-IAKIM IN HOT CLIMATES, 
 
 CHAPTER I. 
 
 FERMENTATION. 
 
 Etymologically, the word fermentation (derived from the 
 
 \h\ fervere, to boil) marks the phenomenon by which the 
 transformation of a part of the substances constituting a 
 given liquid takes place, the phenomenon being accompanied 
 by movements similar to those produced by the boiling of 
 a liquid. 
 
 The term fermentation seems therefore only applicable to 
 cases where chemical transformations are accompanied by 
 a kind of boiling. 
 
 As long as the causes of these chemical transformations, 
 of which the bubbling is only the corollary, were not known, 
 the above definition sufficed ; but since the cause is known, 
 since we know that many other chemical transformations 
 although not accompanied by bubbling are similar to those 
 which gave rise to the word fermentation, it became neces- 
 sary to designate phenomena of the same order by different 
 words, or, as has been done, apply to all, despite its etymo- 
 logical inexactitude, a word which would have a conven- 
 tional signification. 
 
 It is scarcely necessary to speak of Pasteur, as his 
 numerous works on this question are . universally known. 
 It was he who demonstrated, after the unfruitful researches 
 of most eminent scientists, that fermentations were the work 
 of infinitely small organisms called microbes. 
 
 All fermentations have a point in common, which is that 
 a very small weight of organized matter is sufficient to 
 transform relatively considerable quantities of material. 
 
 Thus, a few pounds of beer yeast may produce thousands 
 of gallons of that liquid, and a few grains of acetic ferment 
 are sufficient to transform a cask of excellent wine into 
 vinegar. 
 
 A 2 
 
4 WINE-MAKING IN HOT CLIMATES. 
 
 Non-organized, often very soluble bodies, are known, 
 acting in the same way. For instance, pep sine may trans- 
 form a considerable weight of insoluble fibrin into soluble 
 peptone. 
 
 Fermentations and transformations of this class are some- 
 what similar, and, therefore, the general term of fermenta- 
 tion has also been applied to transformations brought about 
 by soluble ferments. However, to distinguish the two 
 phenomena, the fermentation brought about by organised 
 ferments has been called true fermentation, while that 
 brought about by the soluble ferments or diastases has been 
 named pseudo-fermentation or diastasic-fermentation. 
 
 The microbes or agents of true fermentations exist in 
 infinite variety, they are subdivided into several species, 
 the principal being moulds, yeasts, mycoderma, micrococci, 
 bacteria, bacilli, and vibrios. With regard to the diastases 
 they are also in great variety, and bear different names in- 
 dicating either their origin or behaviour. That known as 
 pancreatine (a mixture of soluble ferments) normally exist- 
 ing in the pancreas, plays a very important part in digestion ; 
 that called amylase renders the starches soluble. 
 
 As a general principle, all fermentation induces in the 
 liquid the disappearance of one or several substances, and 
 vice versa, the appearance of one or several new products. 
 
 The most important of all is the alcoholic fermentation. 
 
 ALCOHOLIC FERMENTATION. 
 
 This is a true fermentation, and is, in the great majority 
 of cases the work of organised microscopical plants, known 
 as yeasts (levures). 
 
 It is the transformation of several substances of an 
 analogous chemical constitution (glucose and other sugars) 
 into alcohol as the principal product, carbonic acid, glycerine, 
 succinic acid, and a few other substances, some of which are 
 not yet completely known. 
 
 We say intentionally glucose and other sugars, although 
 it is well known that alcohol may be obtained from many 
 other substances, starch for example, but these substances 
 are not capable of being directly transformed into alcohol 
 and secondary products. They must first be transformed 
 into glucose or fermentable sugar. 
 
FERMENTATION. 5 
 
 There are, it is true, a few rare exceptions to this rule, 
 and though of very great scientific interest, they remain 
 unimportant in practice. 
 
 The transformation into glucose, of substances forming 
 alcohol, may be brought abont by chemical means, or more 
 often by diastasic fermentations preceding the alcoholic 
 fermentation. 
 
 Sometimes, as happens in the case of a large number of 
 yeasts, the alcoholic ferment secretes a diastase, bringing 
 about the transformation into fermentable sugar. Cane 
 sugar, for instance, only gives alcohol after having been 
 submitted to a diastasic fermentation, which is indirectly 
 the work of the yeast itself, for it is by the aid of a soluble 
 ferment, invertine, secreted by it, that the preliminary pre- 
 paration is accomplished. 
 
 Starting from glucose, the production of alcohol is the 
 result of true fermentation ; starting from cane sugar, it is 
 the result of a double fermentation, one diastasic, the other 
 true. 
 
 The most searching analyses, made on many different 
 cepages, have not revealed in grapes, at maturity, the 
 presence of cane sugar in noticeable quantities. 
 
 Grape must only contains glucoses, as directly fermentable 
 constituents, the two most important being dextrose and 
 levulose, existing in about equal proportions at maturity. 
 Therefore, the vinous fermentation can only be regarded as 
 a true fermentation. 
 
 Alcoholic fermentations are numerous ; the best known in 
 our regions are those furnishing wine, ale, or beer, cider, and 
 perry. But the alcoholic beverages used in different 
 countries, and prepared from very dissimilar substances 
 milk, juice of certain roots are also the result of fermenta- 
 tions analogous to those already mentioned. 
 
 They are all produced by related organisms, but yet not 
 identical. The Characteristic of their common work is the 
 production of alcohol, but they differ individually with 
 respect to the weight of alcohol produced in relation to the 
 weight of sugar consumed, and by the nature and quantity 
 of secondary products formed. 
 
 These secondary products are of two kinds : first, those 
 depending on the variety of the ferment effecting the trans- 
 formation. 
 
6 WINE-MAKING IN HOT CLIMATES. 
 
 The products of fermentation, principal and secondary, are 
 eliminated by the organisms as the result of their work. 
 
 The researches of Pasteur, justly considered unattaekahle 
 from a scientific stand-point, brought about the conceptions 
 we have just briefly described. 
 
 The alcoholic ferment is a plant cell, nourishing and re- 
 producing itself in a suitable liquid, and, as a result of its 
 nutrition, producing new substances utilized by it in turn. 
 
 The agents of alcoholic fermentations are called yeasts, 
 and belong to the order Saccharomyces. 
 
 The first studied and best known is the Saccharomyces 
 Ceremsia, or beer yeast. 
 
 The Saccharomyces Cerevisiae is composed of cells, which 
 appear under the microscope in a lenticular more or less 
 globular shape, often elliptic, and sometimes circular. They 
 measure, on the average, five or six thousandths of a milli- 
 metre in diameter, and are surrounded by a thin membrane, 
 the composition of which is approximately that' of cellulose. 
 
 The yeast cells, according to their age, have varied aspects; 
 when young they appear turgid, full of non-granular highly 
 refractive protoplasm ; when old they seem almost empty, 
 shrivelled, wrinkled, with the protoplasm full of pigment, 
 and more or less opaque. 
 
 The reproduction of these micro-organisms occurs in two 
 different ways, but only one is of interest to the fermentation 
 industry, the reproduction by budding. 
 
 It consists in the cell swelling at one point of its surface. 
 The swelling is full of protQplasm, and, at the beginning, 
 is not differentiated from the protoplasm of the mother cell. 
 The swelling is at first very wide at the base, but contracts 
 gradually until it forms a true ramification on the mother 
 cell. Under ordinary circumstances these ramifications very 
 soon become detached. The cells, in groups of two or three, 
 become separated, and, isolated or not, become new mother 
 cells, ready to reproduce by the same process. 
 
 It goes without saying that to vegetate and reproduce 
 normally, the yeasts must find in the liquid they live in. 
 besides special physical and chemical conditions, elements 
 which are necessary to the constitution of their tissues. 
 
 These elements are of two classes, organic and inorganic, 
 as has been proved by numerous analyses of yeasts. 
 
FERMENTATION. 7 
 
 The thin membranous envelope covering the protoplasm 
 seems to consist of a substance analogous, if not identical, 
 with cellulose. The following analysis, due to Schlossberger, 
 shows this striking analogy : 
 
 Envelope of the Yeast. Cellulose. 
 
 Carbon ... 45-50 ... 44-50 
 
 Hydrogen ... 6'90 ... 6-20 
 
 Oxygen ... 47-60 ... 49-30 
 
 100-00 100-00 
 
 The envelope represents one-fifth to one-sixth of the total 
 weight of the yeast in a dry state. The protoplasm has a 
 much more complex organic and inorganic composition. 
 The greater part is formed of nitrogenous matter, similar to 
 albumen ; but contains also fatty substances. 
 
 The inorganic matters represent about 6 per cent, of the 
 total weight of the dry yeast, they number about one dozen, 
 their respective importance is rather varied. 
 
 Phosphoric acid and potash predominate, the phosphoric 
 acid represents over 50 per cent, of the weight of the ash, 
 the potash about 40 per cent. 
 
 To conclude, the liquid must offer to the yeast, carbon, 
 nitrogen, oxygen, hydrogen, phosphoric acid, potash, and 
 traces of other mineral matters, to insure its development. 
 
 In the must or juices used by different fermentation 
 industries, the sugars furnish carbon, hydrogen, and oxygen. 
 As for the other matters, they exist in various more or less 
 complex forms in the liquid itself. The nitrogen in the 
 form of albumenoid or even ammoniacal compounds. The 
 inorganic matters are constituents of the parts of the plants 
 which furnish the must. 
 
 The characteristic of the yeast is that it consumes con- 
 siderable quantities of carbohydrates (sugars), retaining only 
 a very small proportion (-rVth) for the constitution of its own 
 substance. All the rest is transformed into alcohol and 
 other secondary products already mentioned. 
 
 The work of the yeast is too complex to be expressed by 
 a chemical equation. 
 
8 WINE-MAKING IX HOT CLIMATES. 
 
 The following simple table will show what becomes of 100 
 grammes of glucose under the action of beer yeast, in a 
 liquid suitably constituted : 
 
 Alcohol ... ... ... 46-56 
 
 Carbonic acid ... ... ... 48- 36 
 
 Glycerine ... ... ... 3"25 
 
 Succinic acid ... ... ... 0'6 1 
 
 Glucose used by the yeast for its 
 constitution, and in the formation 
 
 of not clearly defined products ... T26 
 
 100-00 
 
 VINOUS FERMENTATION. 
 
 The vinous fermentation is that by which the must of 
 fresh grapes is transformed into wine. 
 
 Under ordinary conditions, it is a spontaneous fermen- 
 tation. The must does not require to be sown with yeast, as 
 is often done in the manufacture of other fermented drinks. 
 
 At maturity, the grape is covered with micro-organisms, 
 which induce the fermentation of the must. 
 
 This fact was clearly established by Pasteur ; and it is 
 only at the time of maturity that the exterior of the grape is 
 covered with yeast-spores.* 
 
 Grapes protected against outside dust by proper devices, 
 furnish musts incapable of spontaneous fermentation, if 
 they are prepared with the precautions necessary to preserve 
 them from contamination. 
 
 The particles of dust are fixed on the grapes and stalks, 
 and even on any other of the vine organs, by a kind of waxy 
 matter. This forms the grape-bloom. 
 
 Most diverse matters are found side by side, mineral 
 particles, spores of common mildew, germs of wine yeasts, 
 and in still greater number, the germs of a yeast, common 
 to all sweet fruits, but, as we shall see, of no great import- 
 ance in vinification, this is the apiculate yeast. 
 
 The principal factor in vinous fermentation is the elliptic 
 yeast (Saccharomyces ellipsoideus). 
 
 * It was believed for a loner time that the ferment or yeast existed in the 
 pulp of the grape. This erroneous opinion is even now quoted by certain 
 authors. 
 
PLATE I. 
 
 Wine Yeast (Young). 
 
 Wine Yeast (Old). 
 
 Apiculatus Yeast. 
 
FERMENTATION. 9 
 
 In spite of its name it is almost circular, of lenticular 
 shape, transparent, like the yeast of beer, and full of re- 
 fractive liquid when young and active ; more or less full of 
 pigment, opaque, and shrivelled when old or living in an 
 unfavorable liquid. 
 
 The dimensions of the elliptic yeast are about five thou- 
 sandths of a millimetre each way. Its mode of repro- 
 duction is the same as that of the beer yeast, but the 
 ramified form is less frequent in the Saccharomyces ellip- 
 soideus than in the Saccharomyces cerevisice. 
 
 However, if in reality the elliptic yeast is the principal 
 agent of vinous fermentation, it is not so exclusively. The 
 apiculate yeast (Saccharomyces apiculatus) is one of the 
 most widely distributed in nature. Pasteur was the first 
 to indicate its existence on acid and sweet fruits generally, 
 and grapes in particular. Reitsch and Martinand * also 
 indicated the predominance of apiculate yeast on the 
 surface of ripe grapes. 
 
 They have shown, further, that it exists in abundance at 
 the beginning of any spontaneous vinous fermentation. 
 
 Its action, however, is only partial, for it cannot live in 
 must containing more than 3 to 4 per cent, of alcohol. 
 
 Reitsch and Herselin established this fact by a series of 
 conclusive laboratory experiments. f 
 
 The elliptic yeast, on the contrary, is able to work in a 
 much more alcoholic liquid. It commonly gives up to 16 
 per cent, (by volume) of alcohol, t but it really starts work- 
 ing in ordinary cases, that is, in unsterilized musts, only 
 when the fermentation has been commenced by the apicu- 
 late yeasts. 
 
 For vinous fermentation to take place under good con- 
 ditions, and for a must to give not only the maximum 
 yield in alcohol, but also that harmony of qualities which 
 assures its value, the fermentable liquid should realize 
 certain chemical and physical conditions, some of which 
 are still obscure, but others very distinctly established. 
 
 Later on, when discussing the vintage, and vinification, we 
 will study the influence of the chemical and physical con- 
 ditions of the must, on the quality of the wine. We desire 
 
 * Comptes Rendus de 1'Acad. des Sciences, 6 April, 1891. Des micro- 
 organismes des raisins murs. 
 
 t Reitsch and Herselin. Progres agricole et viticcle, 1895. 
 + 28 per cent, of proof spirit. 
 
10 WINE-MAKING IN HOT CLIMATES. 
 
 to draw attention here to the relative inferiority in prac- 
 tice, now long known, of the wine-making industry as 
 compared with other fermentation industries. 
 
 Defects in qualities of wines are of two kinds. Those 
 known as organic, depending on the grape, the cepaye, its 
 state of maturity, the atmospheric influences which it was 
 submitted to, alterations caused by diseases it may have 
 been subject to, &c. 
 
 Against some of these defects nothing very effective can 
 be done ; against others, resulting from vine diseases, for 
 instance, continual care and efficacious treatment are gene- 
 rally sufficient to annihilate them. 
 
 The other qualities or defects, which may be termed 
 accidental, are the result of different manipulations to 
 which the grapes were submitted during their transforma- 
 tion into wine, and of the conditions under which the 
 transformation was effected. Theoretically, the transfor- 
 mation ought to take place under the exclusive influence of 
 the yeasts we have just mentioned, but practically it is not 
 so. 
 
 The vinous fermentation generally remains the principal 
 result, but side by side there are effected a number of other 
 fermentations, which are known as secondary fermentations, 
 because they usually have less influence on the nature of the 
 product. Their action, however, is never nil in practice, 
 and the further the must is from its normal state, the 
 greater their importance becomes. 
 
 In all the industries of fermentation of sweet musts, what- 
 ever the origin of that must is (brewing, distillation, for 
 example), manufacturers do not go groping like blind people ; 
 the conditions of these fermentations, on the contrary, are 
 carefully studied, and care is always taken to realize the 
 most favorable conditions. 
 
 In the wine-making industry this is not done, perhaps 
 because it is the most important of all. This seems to every- 
 body, however, to be a very poor reason. We are more 
 inclined to think that it is because tlie wine-grower does 
 not know, and will not take the trouble to frankly regard 
 himself as a manufacturer during the vintage time. 
 
 We know what objections will be raised against this 
 argument. The grape harvest is only made once a year, 
 whereas, the operations of other industries are repeated 
 every day. We agree that this is a difficulty, but also think 
 
FERMENTATION. 1 1 
 
 that it does not justify either a complete lack of observation 
 or disregard ; it seems, on the contrary, that the necessity of 
 observing the conditions is so much more necessary as the 
 occasions are more rare. 
 
 Are there many vignerons who are able to recall the 
 behaviour of particular vatfuls of the preceding year, the 
 diverse phases of their fermentation, or who possess such 
 a stock of observations as to enable them to deduce the 
 best conditions for the vinous fermentations ? They are 
 rarae aves. 
 
 The characteristic failing of vine-growers is to act without 
 method, and the result is an exceedingly great diversity of 
 processes used in working the raw material, which, after all, 
 does not vary much in composition. 
 
12 WINE-MAKING IN HOT CLIMATES. 
 
 CHAPTER II. 
 
 STUDY OF THE GRAPES. 
 
 MATURATION. 
 
 The phenomenon of the maturation of fruits has been the 
 object of numerous studies. Many eminent scientists have 
 tried to solve this captivating problem, but we cannot yet 
 state that complete light has been thrown on the subject. 
 
 We shall refer here to a study, dating from the last few 
 years only, which is interesting from two points of view 
 first, because it summarizes the principal works on the 
 subject ; secondly, because it is applied to a very important 
 cepage of the southern region of France. 
 
 That cepage is the Aramon, and the Aramon grafted on 
 American vines in extensive culture. 
 
 The researches mentioned date from 1891. In that year 
 the vine which furnished the samples was not submitted to 
 any particular care. In the preceding year it had received 
 an ordinary fertilizing with farm manure composed of 
 arachide shells litter. 
 
 The plot of ground, situated in the commune of Ville- 
 veyrac (Herault), is flat, constituted of clay-limestone soil, 
 limited to the west by a departmental road and by private 
 roads on the other sides. 
 
 The vineyard, planted with Jacquez in 1884, was grafted 
 with Aramon in 1886. 
 
 The samples were taken every fortnight, from the 1st of 
 May to the 21st of September, 1891. The vintage took 
 place on the 28th September. 
 
 The first sample taken on the 1st May represents the 
 whole of the buds ; but, from the 15th of May, it was pos- 
 sible to separate the three principal aerial organs the 
 grape, leaf, and branch and to analyze each separately. 
 
 In this study we will consider more particularly the for- 
 mation of sugar in the grape. 
 
STUDY OF THE GRAPES. 13 
 
 FORMATION OF SUGARS IS THE GRAPE.* 
 
 " Although these experiments were not carried out with 
 the exclusive object of throwing light on the controversy as 
 to the origin of sugars, we shall see that the results may be 
 valued, in presence of the principal hypothesis actually 
 existing on the genesis of the sugars in grapes. As happened 
 with Fortes and Ruyssen, we found ourselves confronted with 
 three theories to explain the essential phenomena of matura- 
 tion diminution of acids and augmentation of saccharine 
 matters for, as we have seen, these two phenomena occur 
 at the same time. 
 
 " 1st. The theory which regards tannin as the generator 
 of sugar. 
 
 " 2nd. The theory which considers starch as the principal 
 source of almost all the organic principles. 
 
 " 3rd. The theory which accords to the acids the part 
 played by starch in the above theory. 
 
 " We have not followed the tannin in the various phases 
 of vegetation, and cannot therefore express an opinion on 
 the first of these theories. It has been, however, almost 
 completely abandoned, 
 
 " With regard to the second, we searched for starch in the 
 different organs and succeeded in detecting it under the 
 microscope, in small spherical granules, greenish, but not 
 coloured blue by iodine, and not luminous in polarized light 
 with the Nicols crossed. Only a few granules of an 
 irregular shape were coloured blue by iodine. 
 
 " The starch with these two characteristics was only found 
 in the seeds of the grape. The granules, however, were 
 smaller than those of ordinary starch comparable in dimen- 
 sions to those of rice starch. 
 
 a We cannot conclude from these succinct results that 
 starch only exists in small quantity, or not at all, in the 
 different organs of the vine. Sachs, Cuboni, Schimper, with 
 less rudimentary methods, consisting of eliminating the 
 chlorophyll by a preliminary treatment, have detected and 
 even estimated the starch in vine leaves ; we have no wish 
 to depreciate the results obtained by these observers, without 
 previously obtaining the support of more convincing experi- 
 ments. 
 
 * L. Roos & E. Thomas. Contribution a 1'etude de la vegetation de la 
 vigne. (Ann. Agronomiques.) 
 
14 WINE-MAKING IN HOT CLIMATES. 
 
 " Starch seems, therefore, to exist in the leaves, and, in a 
 general way, in all the green parts of the plant ; it may 
 therefore be considered as the source of the more or less 
 numerous organic products, particularly the saccharine 
 matters. 
 
 " But this hypothesis has been contradicted by Buignet, 
 who, to begin with, contests the presence of starch in acid 
 fruit. 
 
 " In admitting its presence in the plant, he adds that its 
 transformation could not in any case furnish the sugar of 
 the fruits, as this sugar is Isevogyre, while the glucose 
 derived from starch is dextrose, with a rotation of + 53. 
 This is an argument which seems to dispose of the opinion 
 of Alessandri and Pollacci,* who assert that the sugar is the 
 result of the saccharification of the starch in the pips or 
 seeds ; and that of Leon Brasse,| who studied the trans- 
 formation of starch in a great number of different leaves, 
 amongst which, it is true, the vine leaf does not figure, and 
 demonstrated that a soluble ferment, amylase, existed in 
 all leaves, capable of saccharifying not only the soluble 
 starch, but also crude starch. 
 
 " This appears convincing, but to be really so it would be 
 necessary to know if the vine starch exists only in one 
 modification, and if that modification is that furnishing 
 dextrose by saccharification. 
 
 " We know that the sugar resulting from saccharification 
 of inuline is Isevogyre, and it is not proved that inuline does 
 not exist in the vine. 
 
 " Previous observations due to Deherain established that 
 the rotation of fruit sugars, though at first decidedly positive, 
 diminishes progressively and passes to minus. Later on, 
 Prof. Bouffard, of the School of Agriculture, Montpellier, 
 arrived at similar results while studying Aramon must. 
 Our results entirely confirm those of the two above authors, 
 and allow us to affirm that grape-sugar is composed of an 
 admixture of glucoses in which dextrose predominates before 
 maturity. 
 
 " Buignet asserts that the sugar of fruits is at first in the 
 state of cane sugar, which, later on, by inversion yields 
 glucoses. But the argument he advances against the 
 
 * Botanische Zcitung, 1883. 
 
 t Dissolution de 1'amidon dans les feuilles. Ann. Agronom., t. xii. 
 
STUDY OF THE GEAPES. 15 
 
 amylaceous origin may be turned against him, for if it is 
 true that grape-sugar has about the same composition us 
 inverted sugar in the fruit at maturity, this is not true if 
 it is considered before that epoch, and the inversion giving a 
 mixture in equal parts, Isevogyre, of dextrose and levulose, 
 could not at any moment produce a sugar of positive 
 rotation. 
 
 " To conclude this matter, Boehm has proved that the 
 leaves form starch with the aid of sugar, and that, by sub- 
 mitting plants normally exempt from starch to the action 
 of a saccharine solution, one can, after a while, distinctly 
 detect the formation of starch. 
 
 " Schimper, arguing from his own experiments and those 
 of Boehm, concludes that the appearance of starch in the 
 leaves being always posterior to that of glucose, this 
 cannot have an amylaceous origin, at least in the leaves ; 
 its accumulation in the fruit would therefore be the result of 
 a direct migration in the shape of glucose, or an indirect 
 migration of the glucose transformed previously into ordi- 
 nary starch, and further into soluble starch, which would 
 pass inro the berry to become saccharified. 
 
 "Amylase operates, no doubt, in rendering the starch 
 soluble, and subsequently in saccharifying it. 
 
 "It is also to that ferment that the disappearance of 
 cane sugar should be attributed. 
 
 " However, it is possible to admit that the inversion of 
 the crystallizable sugar furnishes a part of the glucoses 
 detected in the fruit, that a part of those glucoses emanates 
 from the starch, the dextrose being furnished by the 
 ordinary starch, the levulose by a kind of inuline, or, as 
 we will see later on, might have a different origin. 
 
 " Let us now examine our results, in comparison with 
 the theory which sees in the transformation of the acids 
 the genesis of the sugars. 
 
 "From the weights of the grapes, leaves, branches, and 
 the number of branches gathered for each experiment, 
 we intend to establish the composition of an average 
 branch, starting from the 28th June, the date at which 
 the blooming is completely achieved ; and . place in 
 juxtaposition the absolute quantities of acids expressed as 
 sulphuric acid, of saccharine matter as glucose, and of the 
 ashes contained in the different organs. 
 
10 
 
 WINE-MAKING IX HOT CLIMATES. 
 
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STUDY OF THE GRAPES. 
 
 17 
 
 " To enable these results to be readily grasped, we have 
 expressed them by a graphic curve indicating the elements 
 in absolute value at different epochs. 
 
 ABSOLUTE QUANTITIES. OF SACCHARINE MATTER (AS 
 GLUCOSE), OF ACIDITY (AS SULPHURIC ACID), AND ASH 
 CONTAINED IN AN AVERAGE CANE. 
 
 Sugar. 
 
 Acids. 
 
 28 June | 12 July | 26 July | 9 Aug. | 23 Aug. | 6 Sept. | 21 Sept. 
 
 " We have seen previously that the percentage strength of 
 the sugar in grapes increases at the precise moment that 
 the production of acidity diminishes. If we consider the 
 absolute value of the grape, and the average branch, it is not 
 so any more ; the acidity constantly increases in absolute 
 value up to the 23rd August, and the formation of sugar is 
 observed at the same time. 
 
 " The augmentation of the sugar is even enormous, from the 
 9th to the 23rd August, for it is during that period 25 times 
 greater than that observed previously for equal intervals. 
 
 "The variations of the acidity and saccharine matter 
 therefore seem independent of each other at least up to the 
 23rd August. From that date the saccharine matter 
 increases considerably up to maturity, but we observe at the 
 same time, a great diminution in the quantity of the acid. 
 
 10649. B 
 
18 WINE-MAKING IN HOT CLIMATES. 
 
 It seems impossible to admit that the total sugar is derived 
 from the acids, for we notice that the absolute quantity of 
 each increases simultaneously. At the same time, we cannot 
 say that the acids do not furnish their contingent of sac- 
 charine matter. 
 
 " Fremy noticed that the acid reaction of fruits 
 diminishes with ripening, but he also notes that in a great 
 many cases the acids of the fruit do not disappear, but 
 become neutralized by combining with the bases circulating 
 in the plant. If that reaction really occurs in the vine 
 there should be an increase in the weight of the ashes at the 
 precise moment that the free acids disappear. 
 
 " In fact, we notice between the 23rd August and the 6th 
 of September a marked increase in the weight of the ash 
 we cannot say that the totality of the acids disappeared, or 
 have become combined with the bases. For in the preced- 
 ing intervals the weight of the ash was increasing together 
 with the acids. To fix with certainty the destiny of the 
 acids, we ought to be able to measure the whole of the acid 
 produced during a given time. In other words, to know 
 and measure all the acids, at first free, and afterwards 
 combined. 
 
 " It seems to us that a part of them at least is utilized 
 in the formation of organic salts, the bases of which are 
 found in the ashes. 
 
 " What becomes of the remainder ? 
 
 " Although we cannot state that the acidity decreases in 
 absolute value when the saccharine matter is augmenting, 
 we may at least notice that when the acidity decreases, the 
 sugar, composed in greater part of dextrose, changes its 
 composition. 
 
 " This change is very distinctly shown by the polarimetric 
 deviation, which from slightly plus or nil passes to minus, 
 and increases in that direction up to maturity. 
 
 " It will be easily conceived that the necessity for perfect 
 washing, and of diluting the matter in a large volume of 
 water, prevented us from making precise polarimetric obser- 
 vations. We noticed slight plus deviations up to the 
 23rd of August, and at that date the must, which contained 
 5*3 per cent, of glucose, showed no deviation whatever ; on 
 the 6th September the must contained 9 per cent, of glucose, 
 and the observed deviation in a 20-centimetre tube was 
 -12. 
 
STUDY OF THE GRAPES. 19 
 
 " The augmentation of sugar may, therefore, be attributed 
 for the greater part, to the formation of levulose during that 
 period. 
 
 " Prof. Bouffard, already mentioned, concludes in the same 
 way. according to experiments made by him on Aramon 
 cepage, that the dextrose is first formed, and that the 
 levulose appears later on. 
 
 " As the result of our observations, it appears that the 
 diminution in absolute value for the acidity, is always accom- 
 panied by an augmentation of levulose in the fruit, and one 
 is led to think, that if the acids contribute to the fermentation 
 of sugar, it is the levulose that originates from them. 
 
 " We certainly do not want to generalize this hypothesis, 
 or even to apply it to the Aramon cepage in an absolute 
 manner. Our experiments, only conducted during one year, 
 and under given conditions as to soil and climate, ought 
 to be confirmed by new studies or experiments made under 
 different conditions as to soil and climate. 
 
 " We may add that on the 10th August, the acidity of the 
 grapes was constituted by more than 50 per cent, of free 
 tartaric acid, which progressively diminished, and on the 
 21st of September was not detectable." 
 
 COMPOSITION OF RIPE GRAPES OF DIFFERENT CEPAGES IN 
 THE SOUTH OF FRANCE. 
 
 The succinct study of the phenomena of ripening which 
 we have just considered, is only of theoretical interest to the 
 wine-making industry. 
 
 The knowledge of the immediate composition of grapes at 
 vintage time is of much more direct interest. 
 
 Until recently no complete study of the subject had been 
 made. Girard and Lindet have filled this gap, and we will 
 borrow from their very conscientious and complete work, a few 
 general ideas on the composition of the different parts of the 
 fruit, and figures relating to the principal cepages of the 
 South of France.* 
 
 With regard to its apparent structure, the grape is divided 
 into two parts. 
 
 The stalk, that is to say, the ligneous and herbaceous parts; 
 and, secondly, the berries borne by it. 
 
 * A. Girard and L. Lindet. Composition des raisins des principaux 
 cepages de France. Bulletin du Ministere de I' Agriculture, Paris, 1895. 
 
 B 2 
 
20 WINE-MAKING IN HOT CLIMATES. 
 
 The berry comprises three principal organs : the skin or 
 pellich (outside envelope); the pulp, mass of cells filled 
 with juice ; the pips or seeds, reproductive organs, generally 
 disposed symmetrically around the centre of the berry. 
 
 Each of the four parts composing the fruit the support, 
 pellicle, pulp, and seed has a special composition. Each 
 brings to the vat special substances exerting a favorable or 
 unfavorable influence on the wine, proportional to the abso- 
 lute quantity of active substances they may contain. 
 
 As far as vinification is concerned, the grape consists of a 
 liquid part the must, and a solid part the marc. 
 
 The must alone contains all the substances necessary to 
 the fermentation of white wine, sometimes even of a reddish 
 wine, and contains all the substances necessary to the life of 
 the vinous yeast. 
 
 These are, placed in their order of importance (water 
 excepted) : 
 
 Glucoses : dextrose and levulose. 
 
 Organic compounds, acid or not. 
 
 Salts of organic acids (bitartrate of potash). 
 
 Mineral or inorganic salts, phosphates, sulphates, traces of 
 chlorides, &c. 
 
 The mixture of dextrose and levulose is the most important 
 part of the must, these sugars constitute its value, deter- 
 mining the future alcoholic strength, and give to the wine its 
 vinosity through the three principal bodies formed as the 
 result of their transformation, alcohol, glycerine, and succinic 
 acid. 
 
 The organic acids and the acid salts of the must are of 
 secondary importance, but of such relative importance that 
 every vine-grower ought to be able to determine the exact 
 amount of acidity in must. 
 
 It is this acidity which renders the must more favorable 
 to the alcoholic than any other fermentation, when its per- 
 centage is sufficient. It may therefore be necessary to in- 
 crease in practice the amount of the acidity. This operation 
 is often done ; although very frequently in a rather empirical 
 manner, sometimes by acidifying musts which would do much 
 better without it, and not acidifying musts enough which 
 really need the addition. 
 
 AVe shall refer again later on to this operation, as the 
 only one we consider useful for the improvement of certain 
 defective vintages. 
 
STUDY OF THE GRAPES. 21 
 
 The other substances contained in the must contribute to 
 the formation of extractive and mineral matters, after having 
 served to nourish the yeast. 
 
 The must extracted from the interior of a berry without 
 coming in contact with the outside of the fruit is sterile, and 
 will not ferment. It is through the crushing of the grapes, 
 and washing of the skins by the must, that the sowing with 
 yeast occurs. 
 
 The marc, constituting the solid part of the grape, includes 
 the stalks, skins, ligneous part of the pulp, and seeds. 
 
 The fermentation of red wine takes place in the presence 
 of all these organs, unless submitted to special treatment, 
 such as stemming or removal of seeds ; each of these may 
 impart to the wine defects or qualities which it is well to 
 know. Stemming, and removal of the seeds, are opera- 
 tions, especially the latter, rarely used in the manufacture of 
 common wines. 
 
 The stalks contain a number of substances studied by the 
 Italian Professor Comboni. It would not serve any useful 
 purpose to describe these in detail, it will suffice to indicate 
 the principal effect of the stalks. 
 
 They contain tannin which is dissolved by the wine. This 
 is beneficial, but we must not confuse the true tannin exist- 
 ing in small amount in the stalks with certain substances of 
 a disagreeable, bitter, and astringent taste which may pass 
 into the wine. 
 
 These substances, which may all be summed up under the 
 heading, organic acids and salts, are detrimental to the 
 finesse of the wine, as well as to its preservation and im- 
 provement. It is this particular astringent taste of wines 
 fermented on the stalks which resulted in erroneously 
 attributing to them an excessive richness in tannin. This 
 was a mistake ; for Coste-Floret, who advocates with firm 
 conviction the operation of stemming, has proved that the 
 difference of richness in tannin was very slight between a 
 stemmed and non-stemmed vintage. 
 
 On the contrary, Prof. Bouffard asserts that stemming 
 sensibly diminishes the richness in tannin in the proportion 
 ' of 1-15 to 1-60 for the Aramon. 
 
 We are, therefore, confronted with two conflicting state- 
 ments. 
 
 In reality, the stalks of ripe grapes contain only a small 
 amount of tannin, and even if they did not furnish any to the 
 
22 WINE-MAKING IN HOT CLIMATES. 
 
 wine, their presence would play a useful part, that of sub- 
 dividing the marc and facilitating the penetration of the 
 surrounding liquid. 
 
 They may prove inconvenient on account of the detri- 
 mental substances already mentioned, and this will certainly 
 be so if the proportion of stalks is too great. This is very 
 rarely the case for the cepages in the South of France, if the 
 length or duration of the maceration is not too prolonged, 
 and if the temperature of fermentation does not become too 
 high. 
 
 Under the influence of excessive temperature and pro- 
 longed contact with the liquid, the cells of the stalks are 
 softened and disintegrated, and the matters or bodies they 
 contain are directly exposed to the solvent action of the 
 surrounding liquid, helped to a great extent by the elevated 
 temperature. This inconvenience is considerably diminished, 
 or even stopped, if the duration of maceration is reduced and 
 the temperature maintained between recognised limits. As 
 the stalks introduce into the wine elements which assist in 
 the formation of a good foundation, and their presence being 
 mechanically useful, we are inclined to think that preliminary 
 stemming should not be employed in the case of wines for 
 ordinary consumption. We do not find in this practice 
 marked economical advantages, especially if we reduce the 
 noxious influence of the stalks by well-conducted fermen- 
 tation. 
 
 Later on, when discussing stemming, we will go into the 
 question more fully, and give precise opinions about this 
 practice. 
 
 The pellicle or skin constitutes the most important solid 
 organ of the grape in the vinification of red wine. It brings 
 with it the colour, most of the tannin, a notable proportion 
 of extractive and mineral matter, and the greater part of 
 the germs of yeast. 
 
 Armand Gautier* has carried out important researches 
 on the colouring matter of the grape, and more successfully 
 than previous investigators. From the study of this sub- 
 ject he was enabled to establish the formation in the 7 leaf 
 of coloured matters, derived from colourless substances 
 producing ampelochroic acids, which, migrating from the 
 leaf towards the fruit, constitute in the pellicle different 
 colouring matters now known as cenolic acids. 
 
 * Comptes rendus, vols. 84 and 114. 
 
STUDY OF THE GEAPES. 23 
 
 These cenolic acids are all red, but of various shades, 
 according to the cepage: They give the colour to the skin 
 of the grape, and exist in great variety, their chemical 
 composition, although not exactly identical, is close enough 
 to allow it to be practically considered so. 
 
 These colouring bodies are distributed in the cells at the 
 periphery of the grape under the epidermis, in the majority 
 of cepages. 
 
 Quite characteristic is their insolubility in water, except, 
 however, in cepages teinturiers, or varieties derived from 
 them, such as Bouschet hybrids. 
 
 They are slightly soluble in strong, but not in weak acids. 
 This explains the possibility of making white wine from red 
 grapes (a great number of cepages at least) as the colouring- 
 matter does not find in the must before fermentation a 
 proper solvent.* 
 
 The oanolic acids form a chemical group, the properties 
 of which closely resemble those of the tannins, as has been 
 established by Louis Hugounenq.t We, therefore, see at 
 once the importance of the pellicle, for through its oanolic 
 acids and pure tannins it furnishes the wine with useful 
 tannin-like substances. 
 
 The action of the tannins is very favorable, they are good 
 antiseptics and powerful preservatives against the possible 
 future deterioration of the wine. On the other hand, they 
 communicate to the wine that special flavour called by wine 
 tasters charnu, mdcke, grain. 
 
 The pellicle also contains an important odoriferous sub- 
 stance which has been carefully studied by Girard and Lindet. 
 
 " One of the most interesting facts, noticed by us during 
 the analytic study of the different parts of a grape, is the 
 localization in the cellular tissue of the skin of an odorifer- 
 ous substance which gives to the wine of each cepage an 
 essential and peculiar character this substance is totally 
 distinct from the bouquet, which is only formed gradually 
 as the wine becomes matured. 
 
 * According to recent experiments made by Rosensthiel, this opinion may 
 be disputed, at least as far as the fruit sugars are concerned, if not the water. 
 Rosensthiel proved that, when out of contact with air, the colouring matter of 
 fruits is dissolved in their juice by prolonged contact, and especially at an 
 elevated temperature; this, it is understood, without interference of fermenta- 
 tion, in other words, in absence of alcohol. He goes so far as to state that we 
 may preserve the must with the colour, flavour, and perfume of the fresh fruit. 
 A very easily conducted experiment shows that the colouring matter of the 
 grape is not 'soluble in water. It suffices to dilute with water a concentrated 
 alcoholic solution of the colouring matter to precipitate it as a powder. 
 
 t JZecherches nouvelles sur le vins. Imp. A. Storck, Lyon. 
 
24 WINE-MAKING IN HOT CLIMATES. 
 
 " All oenologists know that every wine resulting from the 
 fermentation of a particular cepage has, especially while the 
 wine is young, a characteristic flavour. The wines made 
 from Aramon and Carignane, for instance, from the South 
 of France, and those from Pinot and Garnay, from the Bour- 
 gogne cepages, differ entirely from each other. 
 
 " Expert tasters can differentiate these odours, which 
 must not be confused, as is often done, with the so-called 
 earthy taste. It is not the climate nor soil which determines 
 it, they are peculiar to each cepage, and are often sufficient 
 to characterize it. The influence of climate and soil only 
 modifies them. 
 
 " The origin of these odours has not been indicated up to 
 the present. Our researches enable us to state that they 
 must be sought for in the cellular tissue of the skin, where, 
 ready formed, this odorous matter, which imparts the 
 character to the wine, exists side by side with the colouring* 
 matter, which determines the robe of the wine. 
 
 Vergnette-Lamothe had, it is true, so far back as 1867,* 
 originated the idea that certain essential odoriferous oils 
 existed in grape skins, but the part played by them, and their 
 nature, had not been ascertained so far. 
 
 " It is only in studying the weak alcoholic solutions from 
 macerated skins for the estimation of the colouring matter 
 and tannin, that we recognise the importance of this obser- 
 vation. 
 
 " Each of these solutions after a few days was impregnated 
 with a strong odour reminding us of the flavour of young 
 wine, and were easily differentiated from one another even 
 by non-expert observers." 
 
 The seeds contain a fatty oil which is fairly abundant, and 
 a number of substances some of which would be detrimental 
 to the wine, if they were dissolved. 
 
 Fortunately, the most useful substance the seeds may yield 
 to the wine, tannin, is placed near the periphery in such a 
 way that it enters into solution before any of the others are 
 appreciably affected. The increase in tannin due to the 
 presence of the seeds is not positively proved, although some 
 authorities believe that that substance is completely and 
 quickly dissolved. 
 
 According to Girard and Lindet, " the seed also contains 
 a resinous matter, the formation of which seems to be in direct 
 
 * Le Vin, by Vergnette-Lamothe, p. 335. 
 
STUDY OF THE GKAPES. 25 
 
 proportion to that of the tannin ; volatile acids are also con- 
 tained, which apparently belong to the fatty series. They 
 result from the saponification and oxidation of the neutral 
 oil contained in the nucleus of the seed. 
 
 " The resinous matter is easily soluble in alcohol, slightly 
 soluble in boiling water, and almost insoluble in cold water. 
 
 " By evaporation of these solutions it is deposited in the 
 form of a light-brown powder, which tastes harsh when 
 recently prepared but gradually becomes sweetish. 
 
 " It may be dissolved in alkaline liquids and precipitated 
 from the combination so formed by the addition of an acid. 
 It is easily oxidizable, especially in the presence of alkalies, 
 and through oxidation loses the above-mentioned properties. 
 
 "To summarize, it is analogous to ordinary resins, but 
 more rapidly alterable, and may be placed provisionally on a 
 level with the product extracted from the bark of certain 
 trees by Hoffstetter and Stahelein, and named by them 
 Phlobaphenes. 
 
 " Amongst the properties mentioned above, one of them 
 cannot fail to attract the attention of osnologists, namely, 
 that the harsh taste is progressively attenuated by time 
 that attenuation enables us to account for certain long- 
 known changes in the taste of maturing wines. 
 
 " But the presence of volatile acids detected in the seeds 
 is still more important they probably play an important 
 part in the production of the bouquet." 
 
 We are inclined to think that Girard and Lindet place an 
 exaggerated importance on the substances contained in the 
 seeds. The analogy of the action of time on those substances, 
 compared with its action on wine itself, does not seem to 
 be sufficient to credit them with such importance. The 
 harshness of young wines is generally recognised ; it exists 
 in stemmed red wine, and even red wines fermented without 
 the seeds ; and even in white wines, fermented without 
 contact with either skins or seeds. 
 
 However, if the seeds are not crushed and they never 
 should be their presence is harmless. The epidermis is 
 impermeable enough to prevent the solution of the substances 
 contained in them, which might exercise a detrimental in- 
 fluence on the wine. Besides, they are contained in the 
 centre cells, and their solution is not to be feared, provided 
 that the epidermis is not softened by too prolonged macera- 
 tion. 
 
26 WINE-MAKING IN HOT CLIMATES. 
 
 In short, in the South of France, all the solid parts of the 
 fruit may remain in contact with the must during fermenta- 
 tion, in the manufacture of red wine. Their presence pre- 
 sents some advantages and very few inconveniences. 
 
 COMPOSITION OF GRAPES OF THE PRINCIPAL 
 "CEPAGES" OF THE SOUTH OF FRANCE. 
 
 AKAMOX "CEPAGE." 
 
 Constitution of the bunch. 
 
 1893. 1894. 
 
 Stalks ... ... ... 4-07 ... 3-65 
 
 Berries 95*93 96-35 
 
 100-00 100-00 
 
 Constitution of a berry of average weight 3-69 gr. 
 
 Pulp ... ... ... ... 88-81 
 
 Skin ... ... ... ... 9-45 
 
 Seeds ... ... ... ... 1-74 
 
 100-00 
 
 The 88*81 per cent, of pulp represented 83*4 litres of 
 juice per 100 kilos, of berries. 
 
 Chemical composition of the pulp representing 88*81 per cent, 
 of the weight of berries. 
 
 1893. 1894. 
 
 Density of juice ... ... 1-064... 1-056 
 
 Water ... ... ... 82-46 ... 
 
 Fermentable sugar... ... 14-09 ... 11-48 
 
 Bitartrate of potassium ... 0*62 ... 0-51 
 
 Free tartaric acid I* n o Q TO- 12 
 
 Malic and other acids / '" \ 0-68 
 
 Nitrogenous matter ... 0-27 ... 
 
 Matters not estimated ... 1*61 ... 
 
 Mineral mattersf ... ... 0*13 ... 
 
 Ligneous insoluble ... 0*43 ... 
 
 100-00 
 
 * Expressed as malic acid. The figure for 1893 appears very small and is 
 met with quite rarely. L. R. 
 
 t The potash in combination with tartaric acid deducted. 
 
STUDY OF THE GEAPES. 27 
 
 Chemical composition of the skin = 9-45 per cent, of the 
 weight of the berry. 
 
 1893. 1894. 
 
 Water ... ... ... 76-80 ... 
 
 Tannin ... ... ... 1-27 ... 
 
 Bitartrate of potash ... 
 
 Free acids* ... x 
 
 Ligneous... ... ... 20-10 ... 
 
 Mineral matters ... ... 1-83 ... 
 
 100-00 
 
 Chemical composition of the seeds = 1-74 per cent, of the 
 weight of the berry. 
 
 1893. 
 
 Water ... ... ... ... 34-82 
 
 Oil ... ... ... ... 6-92 
 
 Volatile acidsf ... ... ... 0-57 
 
 Tannin ... ... ... ... 2-56 
 
 .Resinous matters ... ... ... 4-45 
 
 Ligneous ... ... ... ... 48-82 
 
 Mineral matters 1-86 
 
 100-00 
 
 Chemical composition of the stalks 3-85 per cent, 
 (average) of the grapes. 
 
 1893. 1894. 
 
 Water ... ... ... 79*66 ... 78-91 
 
 Tannin ... ... ... 1-23 ... 2-52 
 
 Resinous matters ... ... 1-07 ... 0-87 
 
 Bitartrate of potash ... ... 0-92 
 
 Free acids J ... ... ... 0*33 
 
 Ligneous ... ... 15-71 ... 14-49 
 
 Mineral matters ... ... 2-33 ... l-96 
 
 100-00 
 
 * Expressed as tartaric acid. 
 
 1* Expressed as sulphuric acid. 
 
 + Expressed as tartaric acid. 
 
 The potash in combination with tartaric acid deducted. 
 
28 WINE-MAKING IN HOT CLIMATES. 
 
 CAEIGNAN CEPAGE. 
 
 Constitution of the bunch. 
 
 1893. 1894. 
 
 Stalks ... ... ... 3-00 ... 2-91 
 
 Berries ,.. ... ... 97-00 ... 97-09 
 
 100-00 , 100-00 
 
 Constitution of a berry weighing 2-58 grammes. 
 
 1893. 
 
 Pulp ... ... ... ... 89-40 
 
 Skin ... ... ... ... 7-60 
 
 Seeds ... ... ... ... 3-00 
 
 100-00 
 
 The 89*40 per cent, of pulp represented 83 litres of must 
 per 100 kilos, of berries. 
 
 Composition of the pulp=89'4:0 per cent, of the weight 
 of berries. 
 
 1893. 1894. 
 
 Density of juice ... ... 1*076 ... 
 
 Water ... ... ... 77*85 ... 
 
 Fermentable sugar ... 16*12 ... 12*64 
 
 Bitartrate of potash ... 0*62 ... 
 
 Free tartar ic acid ... ... 1 n - Q 
 
 Malic and other acids .../ 
 
 Soluble nitrogenous matters ... 0*18 ... 
 
 Matters not estimated ... 3*80 ... 
 
 Mineral matters ... ... 0*17 ... 
 
 Ligneous insoluble 0*68 
 
 100*00 
 
STUDY OF THE GRAPES. 29 
 
 Chemical composition of the skins=7'6Q per cent, of the 
 
 berry. 
 
 1893. 1894. 
 
 Water ... ... ... 73-76 ... 
 
 Tannin ... ... ... 1-61 ... 
 
 Bitartrate of potash ... ... 1-Q7 
 
 Free acid ... ... ... 0-70 
 
 Ligneous and not estimated ... 22- 73 ... 
 
 Mineral matters ... ... 1-90 ... 
 
 100-00 
 
 Chemical composition of the seeds ;3 per cent, of the weight 
 of the berry. 
 
 1893. 
 
 AYater ... ... ... ... 33'28 
 
 Oil 7-81 
 
 Volatile acids ... ... ... 0-81 
 
 Tannin ... ... ... ... 0*31 
 
 Resinous matters ... ... ... 1-35 . 
 
 Ligneous and not estimated ... ... 54-66 
 
 Mineral matters ... ... ... 1-78 
 
 100-00 
 
 Chemical composition of the stalks = 2-41 per cent, of the 
 weigh t of the bunch . 
 
 1893. 1894. 
 
 Water ... ... ... 69-50 ... 72-00 
 
 Tannin ... ... ... 1-01 ... 1-02 
 
 Resinous matters ... ... 0-85 ... 1-21 
 
 Bitartrate of potash ... ... 1-10 
 
 Free acids ... ... ... 0-48 
 
 Ligneous and not estimated ... 25-96 ... 22-09 
 
 Mineral matters ... ... 2-68 ... 2-10 
 
 100-00 , 100-00 
 
30 WINE-MAKING IN HOT CLIMATES. 
 
 PETIT-BO USCHET CEP AGE. 
 
 Constitution oj the hunch. 
 
 1893. 1894. 
 
 Stalks ... ... ... 4-40 3-82 
 
 Berries 95-60 96-18 
 
 100-00 100-00 
 
 Constitution of a berry weighing 1-95 grammes. 
 
 1893. 
 
 Pulp ... ... ... ... 85-80 
 
 Skin ... ... ... ... 11-36 
 
 Seeds ... ... ... ... 2-84 
 
 100-00 
 
 The 85*80 per cent represented 80*8 litres of must per 100 
 kilos, of berries. 
 
 Chemical composition of the pulp =85*80 per cent, of th( 
 weight of berries. 
 
 1893. 1894. 
 
 Density of juice ... ... 1-061 ... 
 
 Water ... ... ... 82-11 ... 
 
 Fermentable sugar ... 15*74 ... 15'80 
 
 Bitartrate of potash ... 0* 
 
 Free tartaric acid 
 
 Malic and other acids 
 
 Soluble nitrogenous matters... 0-22 
 
 Matters not estimated ... 0-68 
 
 Mineral matters ... ... 0-08 
 
 Ligneous insoluble... ..." 0-33 
 
 ... 0-18 ... 0-56 
 
 100-00 
 
STUDY OF THE GKAPES. 31 
 
 Chemical composition of the skin 1\-^ per cent, of the 
 weight of the berry. 
 
 1893. 1894. 
 
 Water ... ... ... 77.94 _ 
 
 Tannin ... ... ... 1-Q6 
 
 Bitartrate of potash ... ... j Q3 
 
 Free acids ... ... 
 
 Ligneous 
 Mineral matters 
 
 100-00 
 
 Chemical composition of the seeds 2'84 per cent, of the 
 weight of the berry. 
 
 Wato 38 . 02 
 
 011 ... ... ... 4-48 
 
 Volatile acids ... ... ._ 
 
 Tannin .. ... ... .'.'.' 2-26 
 
 Resinous matters ... ... 4.97 
 
 Ligneous and not estimated ... ... 49-41 
 
 Mineral matters ... 1-76 
 
 100-00 
 
 Chemical composition of the stalks 3*82 per cent, of the 
 weight of the bunch. 
 
 1893. 1894. 
 
 Water ... ... ... 80-30 ... 76-52 
 
 Tannin ... ... ... (>89 ... 1-05 
 
 Resinous matters ... ... 1-01 ... 1-24 
 
 Bitartrate of potash ... ... 1-26 
 
 Free acids ... ... ... 0-26 
 
 Ligneous and riot estimated ... 15-40 ... 17-63 
 
 Mineral matters 2-40 2-04 
 
 100-00 100-00 
 
32 WINE-MAKING IN HOT CLIMATES. 
 
 PICQUEPOUL BLANC CEP AGE. 
 Constitution of the bunch. 
 
 1893. 1894. 
 
 Stalks ... ... ... 4-15 ... 3-04 
 
 Berries ... ... ... 95-85 ... 96-96 
 
 100-00 , 100-00 
 
 Constitution of a berry weighing 2-62 grammes. 
 
 1893. 
 
 Pulp 91-90 
 
 Skin ... , 5-63 
 
 Seeds ... ... ... ... 2-47 
 
 100-00 
 
 The 91-90 per cent of pulp represented 86*6 litres of must 
 per 100 kilos, of berries. 
 
 Composition of pulp = 91-90/>0r cent, of the weight of the 
 
 berries. 
 
 1893. 1894. 
 
 Density of juice ... ... 1*060 
 
 Water ... ... ... 80-67 ... 
 
 Fermentable sugar ... 15-88 ... 16-68 
 
 Bitartrate of potash ... 0-53 ... 
 
 Free tartaric acid { n AA A . Q1 
 
 ii/r v J .LT_ ' ~\ ( v OO ... U ol 
 
 Malic and other acids ) 
 
 Nitrogenous matters ... 0*21 ... 
 
 Matters not estimated ... 1*42 ... 
 
 Mineral matters ... ... 0*30 ... 
 
 Ligneous insoluble ... ... 0*33 ... 
 
 100-00 
 
STUDY OF THE GEAPES. 33 
 
 Chemical composition of the skin = 5-63 per cent, of the 
 weight of the berry. 
 
 1893. 1894. 
 
 Water ... ... ... 73*52 ... 
 
 Tannin ... ... ... O50 ... 
 
 Bitartrate of potash ... ... 0*80 
 
 Free acid ... ... ... O49 
 
 Ligneous and not estimated ... 24-29 ... 
 
 Mineral matters ... ... 1-69 ... 
 
 100-00 
 
 Composition of the seeds = 2-47 per cent, of the weight of 
 
 the berry. 
 
 1893. . 
 
 Water ... ... ... ... 31-31 
 
 Oil ... ... ... ... 8-81 
 
 Volatile acids ... ... ... 0'64 
 
 Tannin ... ... ... ... 0*81 
 
 Resinous matters ... ... ... 1-40 
 
 Ligneous and not estimated ... ... 55*66 
 
 Mineral matters .. ... ... 1-33 
 
 99-96 
 
 Chemical composition of the stalks = 3-50 per cent, (average) 
 of the bunch. 
 
 1893. 1894. 
 
 Water ... ... ... 75-48 ... 72-24 
 
 Tannin ... .... ... 1-30 ... 2-33 
 
 Resinous matters ... ... 0-81 ... 1-40 
 
 Bitartrate of potash ... ... 1-15 
 
 Free acids ... ... ... 0-35 
 
 Ligneous and not estimated ... 20-59 ... 21 -14 
 
 Mineral matters 1'82 ... 1-38 
 
 100-00 99-99 
 
 The grapes used for the manufacture of red wine bring 
 to the vat soluble and insoluble matters, which co-operate 
 in the formation of the wine. The former are submitted to 
 a chemical transformation or are simply dissolved in the 
 liquid ; the latter play a mechanical part, which cannot be 
 disregarded. 
 
 10649. C 
 
34 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 The soluble matters are far the most important ; in the 
 manufacture of white wine they are limited to those con- 
 tained in the pulp, the white wines being fermented without 
 contact with stalks, skins, or seeds. 
 
 This amply explains the difference in richness of extractive 
 matter observed between red and white wine, even in white 
 wine made from red grapes. 
 
 However, the substances contained in the must alone are 
 sufficient to insure largely the healthy life of the vinous 
 ferment whose function it is to transform it into wine. 
 
 We shall see later on in what degree it is useful to modify 
 the composition of the must. 
 
 MATTERS BROUGHT TO THE VAT BY 100 KILOS. OF VINTAGE. 
 
 We have already stated that each of the four constituent 
 parts of the complete fruit stem, skins, pulp, and seeds- 
 bring to the vat special products influencing the wine, either 
 favorably or otherwise, proportionally to the absolute 
 quantity of active substances they contain. 
 
 We have just been studying the percentage composition of 
 each of the four parts of the fruit ; we are now going to 
 show in the following tables, borrowed from Girard and 
 Lindet's work, what is in absolute value the quantity of 
 active or inactive substances brought to the vat by 100 kilos, 
 of Aramon, Garignan, and Petit-Bouschet cepages, that is 
 to say, the three red cepages most widely cultivated in the 
 South of France. 
 
 Name of Product. 
 
 100 kilos, of Entire Bunches bring 
 to the Vat 
 
 Total. 
 
 Pulp. Skins. 
 
 Seeds. Stems. 
 
 A 
 
 Fermentable sugar 
 Bitartrate of potash ... 
 Free tartaric acid 
 Malic and other acids 
 Tannin 
 
 kil. gr. 
 
 ramon cej 
 11-910 
 0-434 
 0-102+ 
 0-579 
 
 kil. gr. 
 wge. 
 
 0-079 
 j 0-062 
 0-114 
 
 0-136 
 
 kil. gr. 
 
 0-043 
 0-074 
 
 0-115 
 0-009 
 
 O-O*L 
 
 kil. gr. 
 
 0-030 
 0-013 
 
 0-097 
 0-032 
 
 0-075 
 
 kil. gr. 
 
 11-910 
 0-543 
 
 0756 
 
 0-254 
 0-106 
 0-230 
 0115 
 0-009 
 0-352 
 
 Resinous matters 
 Soluble nitrogenous matters 
 Oil ... 
 
 ; 230 
 0110 
 
 Volatile acids * 
 Mineral matters t 
 
 NOTE.- For references (*), (f), and (J) see footnotes to next page. 
 
STUDY OF THE GKAPES. 
 
 35 
 
 Name of Product. 
 
 100 kilos, of Entire Bunches bring 
 to the Vat- 
 
 Total. 
 
 Pulp, 
 kil. gr. 
 
 Skins. 
 
 Seeds. 
 
 Stems. 
 
 kil. gr. 
 
 kil. gr. 
 
 kil. gr. 
 
 kil. gr. 
 
 Fermentable sugar 
 
 Bitartrate of potash ... 
 
 Free tartaric acid 
 
 Malic and other acids ... 
 
 Tannin 
 
 Resinous matter 
 
 Soluble nitrogenous matters 
 
 Oil 
 
 Volatile acids * 
 Mineral matters f 
 
 Carignan cepage. 
 
 ... 
 
 13-980 
 0-537 
 J- 0-502 
 
 0-079 
 0-052 
 0118 
 
 
 0156 
 
 
 
 0147 
 
 0110 
 
 ... 
 
 0-032 
 
 
 0-017 
 
 0-009 
 0-039 
 
 0-029 
 0-034 
 
 0-227 
 0-023 
 0-052 
 
 0-061 
 
 Petit-Bouschet cepage. 
 
 13-980 
 0-648 
 
 0-571 
 
 0-156 
 0-073 
 0-156 
 0-227 
 0-023 
 0-370 
 
 Fermentable sugar 
 Bitartrate of potash ... 
 Free tartaric acid 
 Malic and other acids .. 
 Tannin 
 
 12-960 
 0-543 
 
 } 0147 
 
 0112 
 0-047 
 0115 
 
 0-061 
 
 0-040 
 0011 
 0-042 
 
 12-960 
 0-695 
 
 0-205 
 0-218 
 
 Resinous matters 
 Soluble nitrogenous matters ... 
 Oil 
 
 0181 
 
 
 0110 
 0124 
 
 0-050 
 
 0-160 
 0181 
 0-124 
 
 Volatile acids* 
 Mineral matters t 
 
 0-065 
 
 0-073 
 
 not esti- 
 mated 
 
 0-048 
 
 0-081 
 
 0-267 
 
 * Expressed as sulphuric acid. 
 
 t The potash in combination with tartaric acid deducted. 
 J At complete maturity, we have not noticed free tartaric acid in the 
 Aramon grapes, nor in several other cipages. 
 The figure given is very small. 
 
 C 2 
 
36 WINE-MAKING IN HOT CLIMATES. 
 
 CHAPTER III. 
 
 VINTAGE. 
 
 The word vintage has a very wide signification ; it means 
 the gathering of the grapes, the result of the gathering, and 
 the general cellar operations connected with it. In the fol- 
 lowing pages we will mean by the vintage the gathering of 
 the grapes and the produce of that operation. 
 
 The choice of the time for the vintage is an important 
 question to the vine-grower. 
 
 In the South of France, in the few days preceding perfect 
 maturity, the transformation of the berry is so rapid, and the 
 crop exposed to so many dangers, that we may easily con- 
 ceive the haste with which the vine-grower endeavours to 
 place in safety, sheltered against the inclemency of the 
 weather, the fruit of the year's hard labour and uninterrupted 
 care. 
 
 Logically, for the manufacture of table wine, the vintage 
 must be made when the grapes have acquired their maxi- 
 mum of saccharine richness and maximum weight. It is 
 well, therefore, to know some of the processes enabling us to 
 fix the precise moment at which the grapes cannot gain any- 
 thing by remaining longer on the vine. 
 
 These processes are of three kinds, empirical, physical, 
 and chemical. The first, based on the exterior alterations and 
 appearance of the grapes the browning at the base of the 
 stem, the increased transparency of the skin, the way in 
 which the pedicel can be detached from the berry, with a 
 portion of the pulp remaining attached to it, and, above all, 
 the Pollacci process, relying on the close observation of the 
 phenomena of ripening. 
 
 Pollacci noticed that ripening always commences from the 
 outside and works gradually towards the centre of the grape ; 
 it suffices, according to him, to taste the pulp in contact with 
 the seed, and compare it with the pulp in contact with the 
 skin. Complete maturity is indicated at the moment that no 
 difference in taste is detected. 
 
 The physical and chemical means, necessitating special 
 though fortunately simple apparatus, are preferable and more 
 accurate. 
 
VINTAGE. 37 
 
 DETERMINATION OF SUGAR. 
 
 The method most employed in determining the saccharine 
 richness is, according to the density of the must, determined 
 by means of a densimetre, known also as glucometre, 
 mustimetre, gluco-oenometre, &c. 
 
 If accurately graduated, or even if not, provided that the 
 correction is known, they give reliable indications. They 
 differ slightly from one another, in some cases the graduations 
 read on the instruments can only be transformed into sugar 
 by calculation. In other cases the graduation indicates 
 directly the quantity of sugar present. 
 
 They all depend on the well-known law of Archimedes 
 " All bodies plunged into a liquid are submitted from top to 
 bottom to a pressure equal to the volume of liquid dis- 
 placed" 
 
 It is clear, therefore, that if an instrument capable of 
 floating is plunged into the must, the heavier the must, that 
 is to say, the more sugar it contains, the less it will sink. 
 
 The density of a liquid containing a substance in solution 
 is submitted to variations almost proportional to the quantity 
 of the substance dissolved. Grape must, it is true, contains 
 besides sugar a fair proportion of other substances, but their 
 total weight compared with the sugar is negligable. 
 
 The glucometre devised by Dr. 'Guyot, and constructed by 
 the Salleron firm, is, we think, the most convenient of these 
 instruments. It consists of a thin glass tube, widened in 
 cylindrical shape for one-third of its length, and provided 
 at its base with a small bulb. 
 
 The instrument so constructed is adjusted by placing 
 mercury or shot in the bulb, in such a way that when plunged 
 into pure water at a fixed temperature it sinks almost to the 
 top of the tube at that point the zero is marked. 
 
 If now we allow the instrument to float -in a saccharine 
 liquid of which the strength is known, it will sink less, and 
 level with the liquid a figure corresponding with the known 
 strength is marked. 
 
 To complete the graduating, it suffices to divide into pro- 
 portional intervals the space between the zero and the point 
 determined by the experiment. cw r - < 
 
 The graduation of these instruments is usually ready 
 printed on a piece of paper, fixed inside the tube at the 
 required height. 
 
38 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 
 The graduation of the Guyot glucometre, 
 shown in the drawing, presents the advantage 
 of enabling ns to read under three different 
 forms from one observation, giving the richness 
 in sugar expressed as kilogrammes per hecto- 
 litre, the degree Baunie", also called liquor 
 degree, and the quantity of alcohol expressed in 
 volume per cent., which will result from the 
 fermentation of the must, if it is done under 
 favorable conditions, and completely.* 
 
 The Salleron mustimetre only indicates the 
 density of the must, and by means of a special 
 table sold with the instrument we can ascertain 
 from one observation : 
 
 First. The corresponding degree Banine". 
 Second. The weight of sugar in grammes 
 
 per litre of must. 
 Third. The alcoholic strength of the wine 
 
 after fermentation. 
 
 Fourth. The weight of crystallized sugar 
 to be added to one litre of must 
 for the wine to contain 10 per 
 cent, of alcohol by volume. 
 Fifth. The density of the resulting wine, 
 and therefore the weight of 
 one hectolitre the results 
 Enabling us to gauge a cask 
 without measuring the liquid. 
 
 The very complete indications obtained from 
 a single observation, followed by the reading 
 of the table, make it a very handy and useful 
 instrument. 
 
 The gluco-oanometre simply gives the degree 
 Baume\ 
 
 The shape of all these instruments is similar, 
 they are simply areometres of constant weight 
 and variable volume, which means that the 
 volume submerged varies with the density of 
 the liquid. 
 
 * A correction, however, must be made. The Guyot scale always indicating 
 for the determined sugar the weight and alcoholic volume a little in excess, 
 namely, 0*8. This, no doubt, is the result of this scale being calculated on the 
 basis of the theoretical chemical equation. 
 
 IS 
 
VINTAGE. 39 
 
 The different indications given by these areornetres directly 
 or indirectly are useful, but not indispensable. It is neces- 
 sary in order to determine the moment of perfect maturity 
 to . rapidly test for the stationary state of the saccharine 
 weight. For this purpose any densimetre, correct or not, 
 may be used, provided the same instrument is used for each 
 trial. 
 
 The chemical processes for determining sugar are very 
 exact, but are too complicated to be usefully recommended 
 to vine-growers. 
 
 We only attach secondary importance to the exact 
 knowledge of the sugar content of the must. If it is neces- 
 sary to operate with precision in scientific researches, it is 
 not so when we have to deal with wine-making on a 
 large scale, and densimetrical observations are sufficiently 
 accurate. 
 
 DETERMINATION OF ACIDITY. 
 
 This is of great importance, and gives a very good indica- 
 tion of the state of maturity. 
 
 The acidity of the grapes decreases from the change of 
 colour of the berry till maturity, remaining at that time 
 almost stationary, and then increases when the grapes are 
 drying. 
 
 The increase after maturity is only apparent, and does not 
 affect the percentage weight. 
 
 If we measure the absolute quantity of acid in a ripe 
 berry, and in a berry of equal size taken at the same 
 moment, but left attached to the stalk to dry, we do not 
 find a notable diminution in the acids. 
 
 In practice, however, it is easy to detect the above- 
 mentioned stationary state. 
 
 We have often mentioned in previous publications and 
 lectures the necessity for the wine-maker to be able to 
 determine exactly the acidity of the musts, for it is an 
 important factor in the future quality of the wine. 
 
 We will explain later on the reasons which lead us to 
 attach such importance to the acidity. 
 
 In a laboratory, no doubt, and to any one used to chemical 
 manipulations, the determination of acidity is a very simple 
 operation. The necessary apparatus for it always exists 
 even in the most elementary laboratories. In the vineyard 
 
40 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 it is complicated to any one unacquainted with the exact 
 measurements made on small masses, and with the necessary 
 calculations to bring the result to concrete figures. 
 
 The acidimetric apparatus consists essentially of an instru- 
 ment measuring a known volume of the liquid to be 
 examined, a graduated tube or burette for delivering the 
 alkaline solution accurately, and an alkaline solution of 
 previously determined strength as compared with a known 
 weight of acid. 
 
 The neutral point is rendered easily detectable by the use 
 of colouring matters, called in chemistry indicators, which 
 have the property of changing colour in the presence of acids 
 or alkalies. It suffices to have an extremely slight excess of 
 either acidity or alkalinity for these changes of colour to be 
 manifested. 
 
 The natural colouring matter of the grape is itself a good 
 indicator, red in acid solution, changing to green with 
 alkalies. 
 
 For white musts, phenolphthalein dissolved in alcohol is a 
 very convenient indicator. It remains colourless in acid 
 solutions, and becomes purple red in presence of an infini- 
 tesimal quantity of alkali. Agidimetres are numerous and 
 varied in arrangement. They do not all render the measure- 
 ment of acidity 'easy of performance by the vine-grower. 
 
 One of these, constructed by Dujardin,* 
 called Acidimetric tube is the smallest and most 
 simple. It consists of a cylindrical glass tube, 
 closed at its lower end, and bearing graduated 
 marks on the central part. The first division 
 from the bottom indicates the volume of wine 
 or must to be used ; the divisions over it serve 
 to measure the quantity of alkaline liquid ne- 
 cessary to obtain the reaction marking the end 
 of the operation. 
 
 The modus operandi is simple. 
 Pour the must or wine into the tube up to A, 
 adjust the liquid to the level of the division by 
 means of a pipette, and add, if operating on 
 white musts, two or three drops of phenolph- 
 thalein solution. 
 
 Pour in carefully, and in small quantity, 
 
 
 Fig. 3. 
 Acidimetric Tube, 
 
 the titrated alkaline solution, a rosy tint 
 
 * J. Dujardin, successeur de Salleron, Paris. 
 
VINTAGE. 41 
 
 appears, which, however, disappears on shaking. Add the 
 alkaline solution in successive small portions till the last 
 drop colours the solution a permanent rose tint.* 
 
 The acid strength expressed as tartaric acid per litre is 
 given by the figure opposite the level of the liquid in the 
 tube. 
 
 It is a very simple operation, but perhaps less simple in 
 practice than it seems through reading the description. 
 
 The drawback of most acidimetres is that they are operated 
 with small quantities of liquid, and therefore any error in 
 measurement becomes greatly increased when calculated to 
 one litre. 
 
 When the must is measured by means of a pipette it gives 
 good results, but is rather difficult to an inexperienced per- 
 son. The operation seems easier when the measurement is 
 made in a tube, as in the above acidimetre, but the slightest 
 error in agreement between the level of the liquid and the 
 division leads to a considerable error. As for the reading 
 of the volume of alkaline solution, in a burette or tube it 
 always remains uncertain, and leads to errors, and falsifies 
 the result, varying more or less the smaller the quantity of 
 liquid that is operated upon. 
 
 We must, therefore, if we want the vigneron to get into 
 the habit of measuring the acidity of the grape must, devise 
 a simple apparatus, facilitating the operation and working 
 on a sufficiently large volume of liquid to render the errors of 
 reading the divisions negligable ; and giving the acid 
 strength of the must per litre from one observation only. 
 
 We may easily make such an acidimetre with the following 
 pieces of apparatus : Fig. 4. First, a burette, or cylindrical 
 tube, 1 centimetre in diameter, and divided into T Lths from 
 to 20 cubic centimetres, B. Second, a graduated flask 
 with a narrow neck cut off exactly at 100 c.c.m. to allow the 
 measurement of the must to be made simply by filling it, I. 
 A large glass beaker holding 400 cubic centimetres, D. A 
 titrated alkaline solution (potash or caustic soda), E. 
 
 A solution of phenolphthalein, F, of which two or three 
 drops are placed in the must before the operation, and by 
 turning red indicate the end of the operation. 
 
 The acidity of the wine is usually expressed in terms of 
 sulphuric acid per litre. This is a conventional arrangement 
 
 * In the case of red must a greenish colour marks the completion of the 
 reaction. 
 
42 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 not calling for criticism, bat when we have to deal with 
 musts it is preferable to express the acidity as tartaric acid, 
 as it is the only acid used to correct the vintage. It would 
 suffice to titrate the alkaline solution in such a way that one 
 cubic centimetre would neutralize exactly 10 centigrammes 
 of tartaric acid, so that the figure read on the burette would 
 represent the weight of tartaric acid per litre. 
 
 Fig. 4. Portable Acidhnetre. 
 
 But, however simple the use of an acidimetre of this kind 
 may be ? we must draw the attention of the vine-grower to 
 a few details as to the method of operating in order to 
 obtain exact results. 
 
 MODE OF OPERATING. 
 
 Crush with the hands, about 500 grammes of grapes, and 
 squeeze the juice through a cloth. 
 
VINTAGE. 43 
 
 Fill the flask with the must thus obtained until it 
 overflows. 
 
 Pour the contents of the flask into the 400 cubic centi- 
 metre beaker ; rinse the flask with an equal quantity of 
 water (rain water or distilled, if possible) and add it to the 
 must. 
 
 Add to it 4 or 5 drops of phenolphthalein solution. 
 
 Fill the burette to the zero point with the alkaline solu- 
 tion ; deliver the alkaline solution gradually from the 
 burette into the must until the reddish coloration appears 
 permanently. 
 
 When that result is obtained, read on the burette the 
 graduation level with the surface of the alkaline solution. 
 Let us assume, for the sake of argument, that it is 9- 7 ; this 
 means that the must contains 9*70 grammes of tartaric acid 
 per litre, or 970 grammes per hectolitre. In this case it 
 would be unnecessary to add any acid to the must. 
 
 Under these circumstances, even if placed in unskilful 
 hands, this apparatus will give sufficiently exact results, 
 especially if care be taken to make previously a rapid trial 
 giving the approximate acid strength. 
 
 To do so one operates as above described, adding the 
 alkaline solution in fractions of 1 cubic centimetre each. 
 At 8 cubic centimetres, for instance, the liquid has not 
 yet become red ; at 9 cubic centimetres it is completely 
 red, this meaning that the result is between 8 and 9 
 grammes per litre. It will, therefore, suffice to commence 
 the operation again, adding at once up to 8 cubic centi- 
 metres of the alkaline solution, and continuing drop by 
 drop till the appearance of the permanent rose tint. 
 
 A little before obtaining the final tint the liquid becomes 
 slightly brownish. This renders the determination of the end 
 of the reaction rather difficult for beginners. This colour- 
 ing occurs with all musts, even when there is no indicator 
 added, and should not be taken into account. It is in order 
 to diminish it that the must is diluted with water. 
 
 As long as the colour remains brown it need not be 
 further considered than as a precursory sign of the end of 
 the operation : an additional two drops ( T Vth cubic . centi- 
 metre) of alkaline solution added to the must will cause the 
 colour to turn from brown to red quite decidedly. 
 
 A final experiment on the range of colours as above will 
 render this quite clear. 
 
44 WINE-MAKING IN HOT CLIMATES. 
 
 The pieces of apparatus required are easily procured from 
 commercial houses. With regard to the alkaline solution, 
 any scientific pharmacy can supply it to order. The wine- 
 maker may, however, rectify the alkaline solution by dis- 
 solving a known weight of tartaric acid in an accurately 
 measured litre of distilled water (8 grammes, for instance), 
 and using that solution in place of the must it should show 
 on the burette the figure 8, if the titrated liquid furnished 
 by the pharmacist is exact. 
 
 The tartaric acid of commerce is sufficiently pure to be 
 used for the trial, and any pharmacist will weigh it 
 accurately. 
 
 All non-coloured or slightly reddish musts may be tested 
 in the manner above described, but for coloured musts, such 
 as those of the Bouschet hybrids, the end reaction is not so 
 distinct. It is preferable, in this case, to work on must 
 diluted with twice its volume of water, and without an indi- 
 cator. The modus operandi would then be as follows : 
 
 Fill the 100 cubic centimetre flask with must, and pour 
 the contents into the 400 cubic centimetre beaker ; rinse the 
 flask twice with water, filling it each time, and add the 
 rinsings to the must. 
 
 Run in, with constant shaking, the alkaline solution from 
 the burette. 
 
 The diluted must will pass through the following range 
 of colours : Red, violet red, violet, brown, and suddenly 
 become deep green. This indicates the end of the reaction. 
 
 The green colour must not be observed by transmitted 
 light, the liquid being too deep in colour to allow a clear 
 perception of the transition tint, but by rotating the beaker 
 it is easy to detect it in the thin film of liquid wetting the 
 sides of the beaker. 
 
 The wine-maker, therefore, has at command two means 
 quite sufficient to enable him to ascertain the maturity of his 
 crop. First, the glucometre shows when the grapes aje 
 not increasing in sugar content ; second, the acidimetre 
 shows when they are not diminishing in acidity. 
 
 It is desirable for the vintage to be made at that precise 
 moment, for then only can the maximum of alcoholic 
 strength be obtained, and therefore the maximum of 
 pecuniary value, considering, as goes without saying, the 
 common wines of the South of France. The . correction of 
 
VINTAGE. 45 
 
 the acidity, which one is very often obliged to increase, 
 is a simple and economical operation considering the gain 
 of alcohol it brings abont. 
 
 However, that desideratum is not always easy to realize in 
 practice, as the wine-maker is not always able to wait till 
 the opportune moment. 
 
 Many circumstances, amongst which we will note the 
 necessity of assuring the indispensable labour, restrict the 
 desired 6bjects of the large growers; the small grower alone 
 remains master of his vintage. 
 
 In the South of France there is a very marked tendency to 
 vintage sooner than is necessary. We know there are many 
 good reasons to justify this tendency, but we have still better 
 reasons to combat it. 
 
 INFLUENCE OF THE TIME OF VINTAGE ON THE QUALITY 
 OF WINES, 
 
 General observations have shown that early vintages 
 ferment well, and that the resulting wines are judged more 
 favorably by expert tasters. 
 
 We will endeavour to explain why this is so. 
 
 For fermentation to take place under favorable condi- 
 tions, it is necessary for the yeast, which has to transform 
 the sugar into alcohol and secondary products, not to be 
 retarded by the composition of the must or its temperature 
 during fermentation. We know that the yeast cannot with- 
 stand a high temperature, nor too large a proportion of 
 alcohol. Moreover, the higher the temperature the smaller 
 the quantity of alcohol the yeast can withstand. 
 
 If, in the fermentation of an early vintage, we do not notice 
 a slackening in the activity of the ferment, although the 
 temperature is often very high, it simply means that the 
 alcoholic strength is low. 
 
 In a late vintage, on the contrary, the alcohol being in 
 greater abundance, adds its detrimental effect to that of the 
 temperature, and the result of the two actions is to paralyze 
 the ferment, preventing it from transforming the remaining 
 sugar into alcohol. 
 
 The complete disappearance of the sugar will, it is true, 
 in many cases, take place through a slow fermentation, but, at 
 the same time, other organisms will be at work communicat- 
 ing to the wine characteristics which will have the effect of 
 diminishing its organoleptic value. 
 
46 WINE-MAKING IN HOT CLIMATES. 
 
 Even in admitting a complete and rapid fermentation 
 (which is often obtained with a late vintage notwithstand- 
 ing the unfavorable conditions of temperature, if the wine 
 is not to contain more than 10 or 11 percent, of alcohol when 
 completely fermented), the wines resulting are more often 
 than not less appreciated by expert tasters. 
 
 The tasting is very complex, and exceedingly difficult to 
 analyze, especially when we have to judge the pecuniary 
 value of a wine. We must apply for the tasting trial to 
 wine merchants, who always have a tendency to judge 
 more favorably types of wine adapted to their own particular 
 trade. All wine merchants have not the same requirements ; 
 a wine adapted to an export wine merchant's trade would 
 command a higher price than another wine which would 
 have been paid for at the same rate by a merchant selling 
 locally. 
 
 There is, in this instinctive tendency of the wine taster to 
 judge the value of a wine from his own personal stand-point, 
 something disconcerting for scientific researches. 
 
 However, these divergences of appreciation are not very 
 considerable, and if we sometimes find many wine tasters 
 agreeing with each other, to award the same number of marks 
 to a wine submitted to their judgment, they often indicate by 
 different terms the qualities distinguished by them. It is 
 therefore very difficult to determine to what element the 
 wine owes its quality or value, and chemists cannot fail to 
 recognise that an analysis of wine, however complete it may 
 be, cannot give its real organoleptic value 
 
 By comparing these two methods of examination, chemical 
 analysis and tasting, we may endeavour to discover if some 
 of the results of the analysis, are constant for a comparative 
 tasting appreciation, and therefore if we cannot deduce a 
 rule from the great number of cases observed and see if that 
 rule is absolute and shows no exceptions. 
 
 Indeed, a rule may be deduced from the numerous 
 analyses of natural wines of different regions, and to that 
 effect we have studied the analyses published : 
 
 By Professors Gayon, Blarez, and Dubourg, of the wines 
 of the Gironde, for two successive years (1887 and 1888). 
 
 By Prof. Margottet, Director of the Agronomic Station 
 of the Cote-d'Or, of the wines of Bourgogne. 
 
 By Giraud, David, and myself, of the wines of the Herault 
 vintages of 1889 and 1890. 
 
VINTAGE. 47 
 
 The wines of the Giroude and Bourgogne are unques- 
 tionably superior, owing- to their origin ; their average 
 acidity is 5'21 for the former, and 5'98 for the latter,* acidity 
 expressed in terms of sulphuric acid per litre. 
 
 The analyses of the wines of the Herault furnish us 
 with still more suggestive results ; the acidity of the wines 
 for the 1889 vintage averaged 5-15, for the 1890 vintage 
 4-80 ; and everybody knows that the quality of the wines of 
 the 1889 vintage was unquestionably superior to that of the 
 wines produced the following year. 
 
 To sum up, the conditions under which the samples of the 
 1890 crop were taken enable us to deduce conclusive results 
 from the analyses made. 
 
 A jury of wine tasters was asked to express their opinion 
 of the wines ; before analysis the bottles were specially 
 marked, to enable them to be identified later on. The wines 
 judged to be the best were those in which the average acidity 
 was highest. The average result of the analysis gave 5.44, 
 being 0'64 above the average acidity of the other wines of 
 the same year, analyzed at the same time. The opinions of 
 the expert tasters, therefore, very fortunately corroborate 
 what we have been saying respecling the acidity of the must ; 
 and this is not a blind judgment, for the appreciation is 
 constant with regard to natural acidity. The judgment is 
 quite different with regard to artificial acidity ; if we take a 
 wine of medium quality with an acidity of 4*00 for instance, 
 and if that acidity is brought to 5 or 5-5 by the addition of 
 tartaric acid, it will still be declared to be of medium quality 
 by the expert wine taster, for the impression perceived by 
 his palate will be totally different to that resulting from a 
 wine naturally containing 5*5 acidity. 
 
 All wines favorably judged by skilful tasters possess a 
 relatively high acidity, which is never below 4*50 grammes, 
 expressed in terms of sulphuric acid per litre. 
 
 It does not follow that all acid wines are good. It only 
 means that wine cannot be good if deficient in acid. 
 
 We cannot hope, therefore, to make a good wine if the 
 average total acidity does not reach 4-50 per litre. f And in 
 
 *Figures given by P. Paul in his work on Vinification, already mentioned. 
 
 t This amount, however, is only sufficient in the case of a wine of high 
 alcoholic strength. It is too low, for wines containing 8 per cent, of alcohol. 
 
 To calculate the acidity as tartaric acid, the figures expressing it, as sulphuric 
 acid must be multiplied by T53. 
 
48 WINE -MAKING IN HOT CLIMATES. 
 
 southern regions with our cc'pages, a well-ripened vintage 
 does not reach that indispensable acidity, but contains it 
 only in under-ripened vintages. 
 
 For these two reasons ; difficult fermentation and lack of 
 acidity, the wines of late vintages are often classified as 
 inferior when compared with the wines of an early vintage. 
 
 We have tried to discover if by properly correcting the 
 acidity of the vintage it is possible to obtain wine of equally 
 good flavour, but richer in alcohol, by retarding the time of 
 gathering. With this object two lawful means may be used ; 
 the addition of tartaric acid extracted directly from the grape, 
 seems most simple and practical, on account of the facility 
 of estimating it, and its small market price. 
 
 There are also cases where the second crop may be used 
 with advantage,* as advocated by eminent oanologists, such 
 as Prof. A. Gautier. 
 
 Both of these means lead to the same result, for, as we 
 have said in another work,t the acidity of the second green 
 crop is mainly due to tartaric acid. 
 
 During two successive years we made laboratory tests, 
 the results of which have always been excellent, the tem- 
 peratore of fermentation being easily regulated in the 
 laboratory. In cellars this is not possible, at least, not yet, 
 therefore we cannot expect on the commercial scale such 
 satisfactory results, but we have made large scale experi- 
 ments, amongst which we quote the two following : 
 
 1st. At Frontignan (Herault). 
 
 Vineyard well sheltered against cryptogamic diseases 
 (heavier yield than previous year)J. On the 6th September 
 a small vat of 15 hectolitres, was filled with Aramon and 
 Carignan, in the proportion of three to one ; the first racking 
 took place four days afterwards. 
 
 On the 21st September the same vat was filled in, exactly 
 the same way, with the only difference that 60 grammes of 
 tartaric acid per hectolitre were added. The racking again 
 took place four days later. 
 
 * In the Revue de Viticulture, dated 7th September, 1895, an article 
 appeared on this subject. Owing to its importance for local wine-makers, it was 
 translated by one of us (W. P. W.). See the Australian Vigneron. Dec., 1895. 
 And applied by us at the last vintage at the Yiticultural College, Rutherglen 
 (R. D.). 
 
 t Roos and Thomas. Contribution a 1'etude de la vegetation de la vigne. 
 Ann- Agronomiques. 
 
 + The trials were made in 1895, when mildew was very prevalent. 
 
VINTAGE. 49 
 
 From September to February the two wines were kept in 
 25 litre casks, without any special care, or racking or filling 
 up, which allows conclusions to be drawn, as to their 
 respective power of conservation under unfavorable con- 
 ditions. 
 
 The following are the results obtained by the analysis of 
 these two wines : 
 
 Early Vintage Late Vintage 
 
 (Frontinnan). (Frontlgnan). 
 
 Alcohol (by volume) ... 8 '6 per cent. 10*5 per cent. 
 
 Dry extract ... ... 16 '0 grammes 18 '90 grammes 
 
 per litre per litre 
 
 Reducing matters (sugars) traces traces 
 
 Acidity (total) ... ... 575 grammes 6 '01 grammes 
 
 per litre per litre 
 
 The wine of the late vintage is of richer colour than that 
 of the earlier vintage ; the latter did not keep well, it turned 
 and became cloudy. The wine of the late vintage kept in a 
 much more satisfactory manner. 
 
 2nd. In the environs of Thuir (Pyrenees Orientales). 
 
 Vineyard well protected against cryptogamic diseases. 
 On the 12th September, a 70 hectolitre vat was completely 
 filled with Carignan gathered in equal parts from two plots 
 of the same soil, one being manured, the other not ; the 
 racking took place five days later. 
 
 On the 28th September the same vat was filled with 
 Carignan, gathered in the same proportion from the same 
 plots, but 70 grammes of tartaric acid per hectolitre were 
 added. 
 
 The racking took place five days later, and the two wines 
 were afterwards submitted to the same treatment. Here are 
 the results of the chemical analysis : 
 
 Early Vintage Late Vintage 
 
 (Thuir). (Thuir). 
 
 Alcohol (by volume) ... 10'50 per cent. 11 '60 per cent. 
 
 Dry extract ... ... 18 "50 grammes 25 '00 grammes 
 
 per litre per litre 
 
 Reducing matters (sugars) traces 1'25 grammes 
 
 per litre 
 
 Acidity (total)... ... 5 '10 grammes 5 '90 grammes 
 
 per litre per litre 
 
 The wine of the late vintage is richer in colour. It is, 
 therefore, perfectly certain that the time of vintage has a 
 very great influence on the composition of the wine. The 
 figures expressing the alcohol and dry extract are notably 
 higher for the late vintage wine. 
 
 10649. D 
 
50 WINE-MAKING IN HOT CLIMATES. 
 
 But are those wines really better, or will the} 7 simply 
 bring a higher price when placed on the market ? * 
 
 Personally, we think they are better, if the fermentations 
 were not too poor, and if the wines have a sufficient quantity 
 of acid. If, in other words, the vintage has been corrected 
 in such a manner as to obtain wines of an average acidity of 
 4*50 or over, per litre. It is also to be noticed that the 
 detrimental influence of high temperatures is diminished by 
 high acidity. 
 
 Therefore, this reason alone should be sufficient to induce 
 us to increase the acidity of the must before fermentation. 
 The temperature appears of greater importance when we 
 examine the phenomena accompanying the use of tartaric 
 acid in the vintage. 
 
 If the acidity of wine is an important factor for its quality, 
 the ratio of acidity is not alone sufficient to constitute that 
 factor. It is necessary that the acidity should be due 
 exclusively to the acids existing normally in the vintage, 
 even if not quite ripe. Amongst these acids the tartaric acid 
 alone is of importance. We have frequently tried to increase 
 the acidity of a wine deficient in acid (otherwise well consti- 
 tuted, but of medium quality only) by adding tartaric acid ; 
 and to submit it to the judgment of skilful tasters. In most 
 cases the wine was improved, but never enough to be con- 
 sidered a good wine. 
 
 The acidity of the wine should never be due to free 
 tartaric acid in notable proportion ; the tartaric acid dis- 
 appears in the grape as maturity advances, and does not 
 exist at all a few days before complete maturity. 
 
 This is a phenomenon noticed by different authorities, one 
 of them being Prof. Bouifard. 
 
 From researches undertaken in collaboration with Eugene 
 Thomas, in 1891, f it appears that on the lUth of August the 
 acidity of the grape, expressed as 19'90 of sulphuric acid per 
 litre, was half of it due to free tartaric acid, whereas on the 
 21st September the acidity had fallen to 5'60, which was 
 exclusively due to fixation of the other acids of the grape. 
 
 * These four wines were presented to the Central Agricultural Society and to 
 the Departmental Society for the Advancement of Agriculture of the Herault. 
 The wine tasters of the former society called to express an opini n, concluded 
 in favour of the early vintage wines from Thuir, and in favour of the late 
 vintage wines from Frontignan. The wine taster of the latter society found in 
 both cases that the late vintage wines were superior. 
 
 t L. Roos and E. Thomas. Contribution a 1'etude de la vegetation de la 
 vigne. Ann. Agron., 1892. 
 
VINTAGE. 51 
 
 The above figures show the percentage proportion. The 
 analysis made on that occasion enable us to establish the 
 real disappearance of the tartaric acid, so far as free tartaric 
 acid is concerned, but they do not yet show the diminution 
 of the acid in actual value. 
 
 This disappearance, however, is certain, as the following 
 absolute values drawn from the same researches go to prove. 
 
 On the 10th August, 343-60 grammes of grapes contained 
 a total amount of acids equivalent to 6*83 grammes, expressed 
 as sulphuric acid, whereas on the 21st of September the same 
 grapes weighing 753 grammes contained only 4'21 grammes 
 of total acidity. This disappearance affecfs, so far as free 
 acids are concerned, the tartaric and other acids of the fruit, 
 and it is quite probable that it is simply the result of the 
 plant absorbing chemical bases from the soil, converting them 
 into neutral salts through combination with the acids. 
 
 There was, in fact, in the 343*60 grammes of grapes on the 
 10th August, 1-27 grammes of mineral matters, of which 
 0-55 grammes were potash. At the same time, in the 753 
 grammes of grapes gathered on the 21st September, there 
 were 2*86 grammes of mineral matters, of which 1'20 were 
 potash in presence of 4'2 1 grammes of acidity. 
 
 Complete maturity has, therefore, the effect of fixing as 
 saline compounds, especially potassic, a part of the acids 
 forming the normal acidity of the grape, in such a way that 
 if the vintage does not possess at maturity the required 
 acidity, it is not that it does not contain the required acids 
 for that purpose, but that the excessive amount of potash 
 partially neutralizes their properties. 
 
 The addition of tartaric acid to the vintage has the effect 
 of immediately entering into combination with the potash, 
 and has, therefore, the secondary effect of increasing the 
 acidity, by causing the re-appearance in the liquid in a free 
 state of the acids pre-existing in neutral combinations. This 
 effect is so true, that not only do we fail to find any free tar- 
 taric acid in the wines resulting from an acidified vintage, 
 but, further, we can by laboratory experiment find the total 
 tartaric acid added in the form of a surplus of bitartrate of 
 potash. 
 
 This fact has been verified by us frequently, as well as by 
 Prof. Bouffard, who established it a few years ago in the 
 course of experiments on the vinification of Jacquez. 
 
 D ^ 
 
52 WINE-MAKING IN HOT CLIMATES. 
 
 These considerations explain why the addition of tartaric 
 acid to the vintage produces much more favorable effects 
 than the addition of tartaric acid to the wine. 
 
 In the latter case, unless we deal with very small quan- 
 tities, a part of the added tartaric acid remains free, and 
 imparts to the wine that harsh taste, setting the teeth on 
 edge, and contracting the muscles of the mouth in a dis- 
 agreeable manner, which is so characteristic of tartaric acid. 
 
 The experiments we have just been considering are no 
 doubt incomplete. We should also have made trials on late 
 vintage wines non-acidified in order to judge them com- 
 paratively. This did not occur to us at that time, but we 
 intend to complete these experiments at an early date. 
 
 A most remarkable fact noticed during the above experi- 
 ments is that, although we tried to bring the acidity of all 
 the late vintage wines up to the same standard of acidity 
 as those of the early vintage, the late vintage wines remain 
 more acid than those of the early vintage. We expected a 
 diminution of the acidity, as the increase of the alcoholic 
 strength checks the solvent action of the liquid on the bitar- 
 trate of potash. The only possible cause we can see to 
 explain the increase of the acid is an increase of succinic 
 acid. 
 
 There is another plausible explanation. It is a fact that 
 the wines resulting from the above experiments varied con- 
 siderably in intensity of colour, the late wines being much 
 richer in colour. The colouring matters which play the part 
 of acid in the wine are not measured in the must, and it is 
 to the increase of colouring matter that the unforeseen 
 increase of the acidity may be due. But this yet remains to 
 be cleared up. 
 
 The results obtained are, however, of a nature to cause 
 new experiments to be made in cellars, in correcting the 
 vintage, firstly by acidification, and secondly by regulating 
 the temperature. 
 
 We feel convinced that if these two conditions are realized, 
 wine of a much higher class will be obtained by vintaging 
 later than is usually done. 
 
 M. Coste, Departmental Professor of Agriculture of the 
 He"rault, informed us recently that in any vineyard, small 
 enough to allow the vintage to be made rapidly, the date of 
 vintaging should be postponed as much as possible and the 
 musts corrected subsequently. 
 
VINTAGE. 53 
 
 It is not within the scope of this work to discuss the viti- 
 cultural reasons that may interfere with this practice. But 
 if the economical advantages of late vintages were well 
 established, means might be found to reduce the danger 
 there is of leaving grapes too long on the vine. 
 
 We have only aimed at showing by comparative trials 
 that it is possible to obtain wines of very different composi- 
 tion, taste, and value, according to the time the vintage is 
 made. 
 
 IMPROVEMENT OF CERTAIN VINTAGES. 
 
 We have already seen* the quantities of soluble matters 
 brought to the vat by 100 kilos, of different ccpages. In 
 the great majority of cases the vintage does not require to 
 be modified in composition, in order to furnish wines of clean 
 taste and good keeping quality. 
 
 There are cases, however, where improvement of the 
 vintage is necessary. 
 
 The defects most frequently met with are: 
 
 An imperfect bloom on the berries, caused by heavy 
 
 rains, which also soil the grapes with earth. 
 A deficiency in saccharine strength, due either to an 
 invasion of cryptogamic diseases or of unfavorable 
 climatic conditions. 
 A lack of acidity ', always noted during hot and damp 
 
 seasons. 
 
 In the first case the use of cultivated yeasts is indicated. 
 Selected pure yeasts may now be obtained in commerce, or 
 they may be cultivated by vine-growers, carefully choosing 
 only healthy grapes to start with. 
 
 We have had occasion to point out f that some vintages 
 resulting from flooded vines, which had yielded under ordi- 
 nary conditions a turbid muddy liquid, deserving any name 
 except nine, had given, by the use of cultivated yeasts, wines 
 of clean taste and excellent keeping qualities. 
 
 It is, therefore, to cultivated yeasts that recourse should be 
 had, whenever the skins of the grapes, from whatever cause, 
 are deficient in yeast germs, as is often the case in some 
 regions of France. 
 
 * Girard and LinHet, loc. cit. 
 
 f Vinif. et lev. cultivees. Progres agncole et viticole. 
 
54 WINE-MAKING IN HOT CLIMATES. 
 
 The addition of sugar to the must is the remedy for 
 deficiency of sugar in the grapes.* 
 
 DEFICIENT ACIDITY. 
 
 This is very frequently noticed in the South of France. 
 It is a true defect, for the quantity of acid in the must 
 has a very great influence on the development of the yeast. 
 We may lay" down as a general principle that the more 
 acid a vintage is, the greater difficulty ferments other 
 than alcoholic will find in developing. 
 
 The standards of required acidity for a few important 
 cepages are : 
 
 8 grammes of tartaric acid per litre for musts of 
 Aramon, Carignau, and other varieties used for 
 making ordinary wines. 
 
 10 grammes of tartaric acid for Bouschet hybrids. 
 
 12 grammes of tartaric acid for Jacquez. 
 
 Whenever the acid strength is below these standards, it 
 should be brought up to them in order to obtain the maxi- 
 mum quality. 
 
 The acidification of the vintage with tartaric acid is a 
 lawful operation, for it does not add anything to the result- 
 ing wine, if the addition to the must be properly made. 
 
 The acidified vintage, as we have just pointed out, does 
 not furnish a harsh wine, as in the case of wine acidified 
 after fermentation. 
 
 The acidification of the vintage is a common practice in 
 the South of France. Very often it is badly conducted, and 
 frequently done when not necessary. The explanation 
 offered by some vine-growers is that a neighbour did it the 
 previous year and made a fairly good wine. 
 
 The measurement of the acidity of the must is not an 
 impossible operation for vine-growers. Commerce places at 
 their disposal a cheap apparatus reducing the operation to 
 its simplest expression. They are thus enabled to know 
 when it is necessary to add tartaric acid to the vintage, and 
 the figures we have given will enable them to know in 
 what proportion the addition of acid should be made. 
 
 * We have omitted the details of this practice as it is rarely necessary in 
 Victoria. (Trans.) 
 
VINTAGE. 55 
 
 When the quantity to be added to a given vat has been 
 calculated, the acid is distributed by hand, over the grapes 
 in the crusher, as they are passing through. 
 
 We may operate in another way by filling a bucket with 
 the crystals of tartaric acid, and washing with a stream of 
 must from the vat, by means of a pump, until completely 
 dissolved. 
 
 It may sometimes happen, as was frequently observed in 
 1896, that, although resulting from well-matured grapes, 
 the must shows a percentage of acid higher than the figures 
 above mentioned as desirable. This is generally the result 
 in dry and warm seasons. L. Mathieu, in a study on the 
 improvement of acid wines,* does not advise any special 
 process. 
 
 It does not appear that a superabundance of acid is an 
 inconvenience. Wines resulting from rather acid vintages, 
 but well ripened, are always good. In these not very 
 frequent cases, it is to a superabundance of bitartrate of 
 potash that the excessive acidity is due. It simply results 
 in the lees being richer in cream of tartar. 
 
 It is not so, however, if we consider a badly-ripened 
 vintage, as is too often the case in the Centre and East 
 of France. 
 
 We have only addressed ourselves to the hot climates in 
 what we have said so far, where complete maturity can 
 always be obtained. 
 
 * L. Mathieu. Amelioration des vins verts. Heoue cte Viticulture. 
 
56 WINE-MAKING IN HOT CLIMATES. 
 
 CHAPTER IV. 
 
 VINDICATION. 
 
 We will not describe here the details relating to the 
 gathering, or the various methods used to convey the grapes 
 to the cellar, but will only study the fermentation proper. 
 
 VINDICATION OF RED WINE. 
 
 The first manipulation the grapes are subjected to is 
 the crushing. 
 
 Crushing, with very few exceptions, is recommended by 
 all osnologists and practised by all vine-growers. It consists 
 in disintegrating the grapes in such a way that the juice 
 and pulp are expelled from the skin without the stalk or 
 seeds being crushed. The machines used for this purpose 
 are called crushers. 
 
 CRUSHERS. 
 
 The most old-fashioned farm, still used in a few small 
 vineyards, is a kind of kneading trough, with the opening 
 placed above the fermenting vat, in which the grapes are 
 squashed by the rosy feet of young farm girls. 
 
 This is an excellent means of crushing, the stalks and 
 seeds remaining intact, while the vintage is submitted to 
 prolonged contact with the air, for the surface being 
 incessantly agitated insures perfect aeration of the must. 
 
 Crushing by the feet is, however, a tedious and expensive 
 operation, and can only be used by small proprietors. It 
 presents a repugnant feature, however, no matter what 
 cleanliness be attributed to the crushers. This reason alone 
 amply justifies the progressive abandonment of the old- 
 fashioned kneading trough, to the advantage of mechanical 
 crushers. 
 
VINDICATION. 57 
 
 M. Paul, civil engineer, in his work De la vindication* 
 classifies crushers into four groups : 
 
 Simple crushers, operating by compression or pro- 
 jection. 
 
 Stemmer and crusher combined. 
 Extracting crushers, also called continuous presses. 
 Extractor and classifier crushers. 
 
 This last group does not seem to us applicable to true 
 crushers, but rather to a series of apparatus performing a 
 number of operations,- which are not all indispensable. 
 
 The best-known mechanical crusher is that constructed 
 with two cylinders. This is the oldest and most used. It 
 acts by compression (like a rolling mill), the grapes being 
 forced to pass through a limited space, too narrow to allow 
 the berry to escape being crushed. 
 
 Fig. 5. Cylinder Crusher fixed above the Vat. 
 
 It is composed of two cylinders. (Fig. 5.) One with 
 grooves running parallel to the axis, the other with helicoidal 
 grooves. The distance apart of the cylinders is carefully 
 regulated. If too close, only a limited amount of the 
 work is utilized, and if too far apart the crushing is 
 insufficient. The cylinders are rotated at different speeds, in 
 the ratio of 1 to 3, the cylinder with helicoidal grooves 
 revolving fastest. 
 
 They are worked by hand or mechanical power, the work 
 performed corresponding to the regularity of feeding. 
 
 * Paris. J. Fritsch, 1894. 
 
58 WINE-MAKING IN HOT CLIMATES. 
 
 Those worked by hand are usually mounted on wheels and 
 placed above the opening of the vat ; under these conditions 
 the aeration of the vintage is imperfect, the contact with 
 air being almost nil. 
 
 This is, fortunately, a defect which may easily be remedied, 
 as we shall show when discussing aeration. 
 
 One of the greatest inconveniences of the cylinder 
 crushers is that the accidental introduction of a hard body 
 (a stone, for instance) may break the cylinders and stop the 
 work. Attempts have been made to minimize this defect, 
 but so far unsuccessfully. 
 
 The working of such a crusher is laborious. The men 
 must often be relieved, but this only becomes an incon- 
 venience in the case of large cellars. In small cellars, on 
 the other hand, this does not apply, the work being inter- 
 mittent, on account of the loads of grapes arriving at the 
 cellar at intervals. 
 
 A crusher constantly fed and worked by four men, 
 relieving each other at intervals, cannot crush more than 
 3,000 kilos. (6,600 Ibs.) of vintage per hour. The yield of 
 juice for a given cepage is poor with this type of crusher. 
 This is only a defect in the case of white wine, especially 
 when made from red grapes. 
 
 If the vintage is crushed by means of a double crusher 
 (with four cylinders) the yield of juice is notably increased. 
 
 Finally, this type of crusher is good, and will long remain 
 the most practical, for small and medium sized cellars. 
 
 The depth of the grooves is of importance ; if too shallow 
 the rolls cannot draw the grapes through, and they form 
 a, vault over the cylinders or slide over them. 
 
 If too deep they cannot do good work, if the cylinders 
 are too far apart ; or crush both stalk and seeds if the 
 rolls are too close together. Ihisis an objection raised by 
 P. Paul against large grooves. 
 
 In a report on cellar appliances read before the Inter- 
 national Viticultural Congress held at Montpellier, in 1893, 
 Paul states that grooves geared into one another do not give 
 good results. 
 
 This criticism does not seem to be fully justified. 
 
 If we consider the case of grooves sufficiently large to 
 allow the grapes by their elasticity to become adapted to the 
 shape of the grooves, without being torn to pieces, we may 
 hope for satisfactory crushing, without the seeds or stalks 
 being ground. 
 
VILIFICATION. 
 
 59 
 
 This is exactly 
 what M. Blaquiere, 
 of Beziers, tries to 
 realize with his fluted 
 cylinder grape com- 
 pressor^ which con- 
 sists of two cylinders 
 with six large longi- 
 tudinal flutes, G G, 
 geared without 
 touching, in such a 
 way that all the sur- 
 faces during rotation 
 are at a constant dis- 
 tance apart, and are 
 revolved in opposite 
 directions by means 
 of outside cog-wheels 
 worked by hand, 
 whim (horse), or 
 steam power. 
 
 Fig. 6. -Blaquiere's Crusher (side elevation). G G, crushing 
 cylinders ; T, hopper ; V, crank wheel. 
 
 ! V 
 
 The fluted 
 cylinders of the 
 hand model are 
 75 cm. (30 inches) 
 long, with an ex- 
 terior diameter 
 of 29 cm. (Hi 
 inches). They are 
 mounted parallel 
 to one another on 
 steel shafts, and 
 revolved in unison 
 by two equal 
 pinions. At the 
 extremity of one 
 of the shafts is 
 
 Fig. 8. Blaquiere's Crusher (front view). G, crushing cylinders ; 
 T, hopper; V V, crank wheels. 
 
60 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 another large cog-wheel, revolved by means of a pinion 
 keyed on the same shaft as the crank. 
 
 The ratio between the large cog-wheel and the pinion is 
 , which means that one complete revolution of 
 
 or 
 
 the fluted cylinders corresponds to 8J revolutions of the 
 crank. The movement is slow enough, and the depth of the 
 flutes sufficient to prevent the vintage sliding on the surface 
 without being drawn down. 
 
 Fig. 7. Blaquiere's Crusher (top view).- G G, crushing cylinders; 
 V V, crank wheels. 
 
 A crusher of this kind performs more work than one with 
 ordinary cylinders. 
 
 The crushing which results is satisfactory ; all the grapes 
 get squashed, the other parts remaining uninjured. 
 
 Blaquiere's crusher is comparatively novel, and has not 
 yet been, to our knowledge, described in detail. We con- 
 sider it an excellent machine, but it has the defect common 
 to all compression crushers, that of liability to damage 
 through the accidental introduction of any hard body 
 (stones, &c.). 
 
 This, however, rarely happens, as the hard body generally 
 crushes with the rest, but an accident during vintage time 
 leads to so many grievous consequences that its occurrence 
 should be rendered almost impossible. 
 
 Later on this matter will be considered when studying 
 stemmers, as the stemmer attached to this crusher presents 
 some interesting details of construction. 
 
VINDICATION. 
 
 61 
 
 n 
 
 A new, very interesting, 
 and original crusher, based 
 on a principle which has 
 never been applied before to 
 grape crushing, has been 
 invented by P. Paul, called 
 the A ero-crushing-turbine. 
 
 Although only four or five 
 years old, the machine has 
 been modified in several 
 details by the inventor. 
 
 Fig. 9. Aero-crushing-turbine. P. Paul (diagram). 
 
 Fig. 9 shows the outline of the machine, and Fig. 10 its 
 elevation. 
 
 Fig. 10. Aero-cruahing-turbine, P. Paul, provided with an elevator feeding stemmer and drainer. 
 
62 WINE-MAKING IN HOT CLIMATES. 
 
 In the report of the International Viticnltural Congress, 
 held at Montpellier,* the following simple and clear descrip- 
 tion of this machine is given : 
 
 " P. Paul, constructing engineer of Cette, is the first 
 to have applied centrifugal force to the crushing of grapes. 
 His system has been described by so many viticultural 
 authorities in various reviews, that it will suffice to htate that 
 the squashing of the berry and liberation of the must is 
 obtained by projecting the grapes against the vertical walls of 
 the fixed cylinder of the turbine. With the speed of rotation 
 properly controlled we are certain to squash all the berries 
 without crushing either the seeds or the stalks, points of 
 great practical importance. 
 
 " To break the tissue of the seeds or stalks the speed of 
 rotation requires 'to be infinitely greater ; and in this lies the 
 original and important point, the perfect selection between 
 the matters to be crushed, and those the crushing of which 
 would prove useless, or even detrimental. 
 
 " M. Paul's turbine is a crusher, not a compressor. It 
 liberates the juice from the berry, and delivers both marc 
 and juice together ; to effect their separation various devices 
 are required, according to the nature of the wine to be made. 
 
 "The prize (vermeil medal) awarded was the only one 
 placed by the Congress at the disposal of the jury to be 
 granted for grape crushers. 
 
 " M. Paul exhibited two types of turbine : one worked by 
 hand, the other by steam power. The first was tried by the 
 jury at the doniaine des Gausses (vineyard owned by Prosper 
 Gervais). The grape passed through, was Aramon. Out of 
 1,150 kilos. (2,530 Ibs.) of vintage, 708 kilos. (1,557 Ibs.) 
 of white must were extracted in twenty minutes. 
 
 "The yield given by the machine was therefore 61 '5 per 
 cent. It was worked by four men, two to operate each 
 crank. 
 
 " Later on, apart from official trials, it was tried at the 
 Chateau de Villeroi (Compagnie des Salins du Midi) with a 
 dynamo-metric crank, with the following results : 
 
 " With Terret-Bourrets the force required to crush one 
 kilo, of vintage was 27-20 kilogram-metres, of which 3'504 
 kilogram-metres was expended in rotating the apparatus. 
 
 * Etienne Gervaise. Congres International Viticole de Montpellier. 
 
VINDICATION. 63 
 
 u With Aramoii the force, required was 23'10 kilogram- 
 metres. 
 
 " Therefore two men are not sufficient to work the 
 machine, as they cannot develop more than 12 kilogram- 
 metres (Claudel. Formules, &c., p. 14.) 
 
 " It would be interesting for the constructor to try and 
 manufacture a machine capable of being worked by two men. 
 It is easy to see from what has been said that such a machine, 
 might crush 20,000 kilos. (44,000 Ibs.) of vintage per day, 
 which is all that is required by the medium proprietor. 
 
 " The Aero-crushing-turbine worked by steam power, was 
 seen by the jury working in the domains du Mdle, near 
 d'Aiguesmortes, with the vintage in full swing. 
 
 u It was fed by an elevator (Burton system), at the same 
 time the must was elevated by a rotary pump, the whole 
 being worke,d by a 5 h.p. engine. 
 
 " The yield of must was rather difficult to determine, for 
 marc and juice fell together into a tank, from which it was 
 conducted to the press. The following are the results 
 obtained, taking as liberated must that which flowed naturally 
 after the press was charged : 
 
 " From 2,879 kilos. (0,333 Ibs.) of vintage (Aramon) 1,379 
 kilos. (3,033 Ibs.) of white must were extracted. The yield 
 in must was therefore 47*8 per cent. But it should be 
 remembered that the marc still remaining in the press con- 
 tained a large quantity of must, liberated from the pulp, 
 which further drainage would have removed. 
 
 " The machine is of very simple construction, and we can- 
 not see a priori any possibility of its getting out of order. 
 We may mention that at the cellar of Yilleroi (Compagnie 
 des Salins du Midi), after being used last year on trial, the 
 machine was installed permanently this year, and that it 
 has worked without a breakdown, and crushed from 180 to 
 200 tons per day. Dynamo-metrical tests have not been 
 made on this turbine, but it is supposed that it requires a 
 motive force of from 4 to 5 h.p. 
 
 " At Villeroi, as well as at Mole, the turbine is fed by two 
 elevators. This is a very important item for the success- 
 ful working of the machine. But the turbine is not the 
 only machine requiring regular feeding, this being a sine 
 qua non condition for the proper working of all continuous 
 machines. 
 
64 WINE-MAKING IN HOT CLIMATES. 
 
 " Finally, another important advantage of the turbine is 
 that the marc is much easier to press, the cellular tissue 
 of the berry being completely destroyed, and with it the 
 elasticity which is such a great obstacle in the pressing of 
 the fresh vintage." 
 
 Such is the judgment of the Commission of the Inter- 
 national Viticultural Congress. It is favorable to the 
 machine worked by steam, but perhaps rather vague with 
 regard to the turbine worked by hand. 
 
 The report of the Commission ends up with " The Aero- 
 crushing-turbine gives excellent results where mechanical 
 power is available," but adds it " has not yet received the 
 sanction of general usage." 
 
 However, the turbine working on a large scale has been 
 installed in a number of cellars long enough to enable us 
 to appreciate it. In conclusion, it is an excellent machine 
 for large cellars. 
 
 We must add to the advantages expressed in the above 
 report the perfect aeration of the vintage. The must 
 coming out of the turbine is, so to speak, an emulsion of 
 air and must. 
 
 We have not measured the amount of air emulsionized, 
 but according to various reports published by the inventor, 
 it is 5 per cent, in volume. 
 
 These are, as we shall see later on, very favorable condi- 
 tions for a good start in the fermentation. 
 
 The various advantages of this highly original crushing- 
 machine justify the as yet uncontradicted success which 
 welcomed it from its first appearance. 
 
 As we have already stated, the regularity of the feeding of 
 crushers has a great bearing on the perfection of their work. 
 The mode of feeding will vary greatly according to local 
 conditions, and the various means by which the elevation of 
 the vintage to the crusher are obtained. 
 
 In most cases the arrival of the drays to the level of the 
 top of the vats by means of a gradient is recommendable ; 
 in that case the feeding takes place by pouring the contents 
 of the tubs directly into the crusher. 
 
 Chain and cup elevators are good, and comply with various 
 required conditions. They are recommendable for large 
 cellars, but may also be arranged and worked by hand in 
 small places. 
 
VINDICATION. 65 
 
 These elevators may be used with either fixed or movable 
 crushers. In the first case, it is necessary to have means of 
 conveying the must from the crusher to the vats (in many 
 cases simply by a wooden shute) ; in the latter, the elevator 
 being- fixed on a truck running on rails, may be moved 
 alongside the cellar ; when established in this manner, even 
 if outside the cellar, the elevator may fill two parallel rows 
 of vats with a simple shute conveying the crushed vintage 
 from the top of the elevator to the fermenting vat. The 
 crusher in this case is moved on another truck parallel to 
 the elevators. 
 
 We must add that a few vine-growers (though quite 
 exceptionally) consider crushing useless, regarding the result 
 of the different manipulations the grapes are subjected to, 
 before being placed in the vat, as quite sufficient. 
 
 Whether the vintage is elevated -by a cup elevator, or 
 thrown into the vat by means of shovels, it acts certainly 
 as a partial crushing ; but, the use of crushers is preferable 
 and indispensable when making white wine. 
 
 Crushing is praised by the majority of oanologists, and is 
 an excellent practice, as it enables the fermentation to get a 
 good start, and facilitates the drainage of the marc. 
 
 In uncrushed or badly-crushed vintages, we always find 
 grapes remaining attached to their pedicle, intact, and filled 
 with unfermented must. When pressed these grapes .burst 
 and contaminate the wine with fermentable substances, 
 which only have at their disposal old yeast, living with 
 difficulty in a liquid *almost completely fermented. The 
 work done by the ferment in this case is very slight, 
 frequently the sweetish wine resulting becomes the prey of 
 noxious ferments, which, except in the case of sterilized 
 must, always exist in the wine, awaiting favorable conditions 
 to multiply. 
 
 The presence of unfermented sugar fills one of these 
 conditions. 
 
 STEMMING. 
 
 -This operation, which consists in separating the grape 
 from the stalk, has been known from ancient times, and 
 is a necessary practice in some viticultural regions, such 
 as Bordeaux. 
 
 In the South and South-west of France, however, it is 
 only occasionally practised. 
 
 10649. E 
 
66 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 In former times it was performed by means of a kind of 
 rake, with teeth fixed far enough apart to allow the grapes 
 to pass between, but placed close enough to retain the stalks, 
 the operation being done over a screen ; it is an expensive 
 method and gives very imperfect results. 
 
 STEMMERS. 
 
 Only mechanical stemming is employed nowadays. It is 
 done by means of special machines called stemmers, gene- 
 rally attached to the crusher, and performing the sorting as 
 the crushing is going on. 
 
 The steminer consists of a horizontal perforated cylinder 
 or cylindrical envelope, in the axis of which a shaft revolves 
 bearing helicoidally mounted boards (Fig. 11) or spikes. 
 
 Fig. 11. - Stemmer fixed above the Vat. 
 
VIN1FICATION. 
 
 67 
 
 The shaft, studded with spikes, or carrying boards, is 
 revolved rather rapidly together with the crasher. 
 
 The crushed vintage falls into the stemming cylinder. It 
 is then energetically beaten by the spikes, separating the 
 grapes from the stalks. The former, together with the 
 juice, fall through the perforations into the collecting trough ; 
 the latter gradually work their way to the extremity of the 
 cylinder, and are then expelled. 
 
 Blaquiere, the constructor of the crusher previously 
 described, has also invented a stemrner, which differs in 
 many respects from the ordinary appliance. 
 
 It consists of a per- 
 forated cylinder revolving 
 round an axle. This 
 cylinder is provided inside 
 with from three to six 
 pieces of wood, projecting 
 a few centimetres, and 
 placed parallel to the axis. 
 The cylinder is inclined 
 horizontally and revolves 
 slowly. 
 
 The crushed vintage 
 falls into the raised end of 
 the stemmer, and is then 
 caught by the projecting 
 pieces of wood and carried 
 onwards to the lower end 
 by its own weight. 
 
 The shocks resulting 
 from the successive falls 
 of the bunches completely 
 detach the grapes from 
 the stalks, . the grapes 
 falling through the per- 
 forations. The forward 
 movement of the stalks 
 results from the inclina- 
 tion of the cylinder, every 
 fall carries the stalks 
 towards the outlet, and 
 
 E 2 
 
68 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 with a machine of this kind it is only after a considerable 
 number of falls that the stalks are finally expelled. 
 
 Fig. 13. Blaquiere's Combined Crusher, Drainer, and Stemmer (front view). 
 
 ADVANTAGES OF STEMMING. 
 
 Stemming is not much practised in the southern regions 
 of France, and does not seem to be generally called for in the 
 manufacture of red wine. It is, however, advocated by many 
 authorities, such as Coste-Floret, who has used it for more 
 than ten years on his extensive vineyard*, and recommends 
 the practice strongly. 
 
 Stemmed wines, according to Coste-Floret, have more 
 jinesse, are more alcoholic, and have better keeping qualities, 
 than wines from the same vintage made without stemming. 
 
 He admits that wines made from stemmed grapes will have 
 to force their way, as the public taste has been always culti- 
 vated for wines from unstemmed grapes. 
 
 " The difficulty that the stemmed wines have to encounter is 
 due, according to Coste-Floret, to the depraved taste of a 
 certain class of consumers who formerly drank our common 
 wines from non-stemmed grapes, but who appear to have now 
 abandoned us. We must create a new market if we do not 
 wish to see our wines discarded and used as raw material for 
 
 * Saint Adrien, near Beziers. 
 
VINDICATION. 69 
 
 manipulations which do not deserve to be encouraged, and we 
 must make wines of good quality, able to be sold directly as 
 natural pure wines." 
 
 Indeed, it is truly desirable that our wines should not be 
 discarded, and they should certainly be consumed without 
 sophistication, but is it not excessive to think, as Coste- 
 Floret appears to, that an important class of consumers no 
 longer drink our wine, and that it should be necessary to 
 stem the grapes to induce them to return to this custom. 
 
 We are not of the same opinion. Wines made from 
 stemmed grapes have more finesse and are slightly more 
 alcoholic than wines from unstemmed grapes, but, contrary 
 to Coste-Floret's opinion, they have poorer keeping qualities, 
 and contain less dry extract. 
 
 The greater richness in dry extract of wines from un- 
 stemmed grapes is a well-known fact, and we shall presently 
 quote some figures to prove this ; but is the excess in dry 
 extract due to the stalks ? We do not think so. 
 
 We have previously seen how small the proportion of 
 stalks is in our southern regions, and how small also the 
 percentage of soluble matters contained in the stalks. It 
 is only 'by grammes that we express the soluble matters 
 brought to the vat by 100 kilos, of vintage of Aramon, for 
 instance, and, even then, the greater proportion consists of 
 tartar and tannin. 
 
 The great richness of wine from unstemmed grapes in dry 
 extract cannot therefore be attributed to the stalks, but 
 simply to the mechanical part played by them in dividing 
 the marc and facilitating the penetration of the surrounding 
 liquid, and therefore its solvent action. We must reject any 
 idea of unfavorable influence of the stalks, on account of their 
 small proportion in all our southern cepayes, and of the 
 small quantity of soluble matter they contain, provided they 
 have not been bruised by the crusher, and that the fermen- 
 tation has been well conducted. 
 
 We do not deny the usefulness of stemming in some 
 special cases, in that of damaged vintages for instance, but if 
 its efficacious action is evident in such a case, it must not be 
 attributed to the fermentation of the grapes after separation 
 from the stalks, but rather to the more or less perfect 
 rejection of damaged from undamaged vintage, which is 
 the result of the stemming, owing to all the rotten and 
 dried grapes being separated with the stalks. In the case 
 
70 WINE-MAKING IN HOT CLIMATES. 
 
 of a healthy vintage, and of cepages where the proportion 
 between the stalk and the grape is not greater than in our 
 cepages in the South of France, we do not see the necessity 
 of advocating the general adoption of this operation. 
 
 In any case, the action of the stemming is only secondary, 
 not direct. The properties distinguishing stemmed from 
 non-stemmed wine, are only the result of had fermentations 
 due to unfavorable temperature, or of remaining too long on 
 the marc. The defect in the case of wine from non-stemmed 
 grapes is not to be imputed to the stalks, but to an increased 
 maceration of the other parts of the marc, to which the pene- 
 tration of the wine is facilitated by the presence of the 
 stalks. 
 
 M. Yincens, Professor in the School of Agriculture at 
 Ondes, starting from the idea that the market value of 
 wine depends on four principal factors the alcoholic 
 strength, dry extract, acidity, and coloration studied 
 methodically the influence of stemming on these four 
 factors. 
 
 The trials were carried out for three cepages Negrette, 
 Aramon, Petit-Bouschet an equal quantity of wine being 
 made from each, with and without stemming. 
 
 AVe will quote his results.* Noting that the stemming 
 was done by hand. 
 
 Composition of Experimental Wines. 
 
 Alcohol T^, Acidity as n . _ . .. 
 
 - " 
 
 Negrette, stemmed 89 16 "5 3 '66 3rd violet red 175 
 
 ,, not stemmed 8'7 17'5 3'80 200 
 
 Aramon, stemmed 8 '8 19'5 5 "58 4th - 440 
 
 not stemmed 8 "75 20 '4 5'11 445 
 
 Petit-Bouschet, stemmed 8 '9 19-4 4'37 3rd 80 
 
 not stemmed 8 '9 21 '3 4 '46 65 
 
 " The above trials were made with the usual instruments 
 found in trade Salleron's ebulliometre ; Houdart, oano- 
 barometre, and Salleron's colorimetre. 
 
 The acidity was determined with a normal potash solution. 
 
 " The observations of temperature, which we consider 
 useless for this table, show that in all cases the maximum 
 temperature was 1 higher, and took place one day earlier, 
 in the non-stemmed than in the stemmed vintages. These 
 
 * Revue Internationale de viticulture ct d'cenologie t. I., No. 4. 
 
VINDICATION. 71 
 
 results confirm the well-known fact, that the presence of 
 stalks in the vat accelerates the fermentation. 
 
 " When examining the composition of the wines, we see 
 that the increase in alcoholic strength due to stemming is 
 very slight. It is nil for Petit-Bouschet, insignificant for 
 Aramori, and reaches two-tenths of a degree for Negrette. 
 This difference is evidently due to the fact that during the 
 submersion of the marc, which was only done in the case of 
 Negrette, the stalks absorbed a greater quantity of alcohol. 
 
 " The differences between the figures for dry extract is 
 much more noticeable. It varies from 0*8 to 1*9 grammes 
 per litre, and constitutes a disadvantage for the non-stemmed 
 wines* which contain less. We noticed, in estimating 
 the astringent matters according to the process of Aime" 
 Girard, that the difference was almost entirely due, with 
 the exception of Aramon, to the ceno-tannin, an excellent 
 agent in the preservation of wine. 
 
 " Except for the Aramon, which has a very peculiar com- 
 position, the acidity is higher in non-stemmed wine ; although 
 the difference is very slight, we must take into consideration, 
 in the case of our southern wines, which are generally flat, a 
 lack of fresh, cool, acid taste. 
 
 " If we now examine the colour, the figures representing 
 its intensity being in inverse proportion, we see that the dif- 
 ferences in favour of non-stemmed wines are nil for Aramon, 
 one-eighth for Negrette, one-fifth for Petit-Bouschet. t 
 
 " To the taste the .stemmed wines were less harsh or rough 
 than the non-stemmed, but these were mOTefruites, corses, 
 and they would unquestionably be preferred by wine mer- 
 chants. 
 
 " As the stalks always absorb a certain quantity of wine, 
 an increase in yield of 2 per cent, is due to the stemming, 
 but this augmentation not covering the cost of extra mani- 
 pulation we need not take it into consideration. 
 
 " To sum up, in our experiments stemming has always 
 furnished inferior wines, less rich in dry extract and 
 colouring matter, and only slightly different in alcoholic 
 strength. 
 
 * We quote exactly, although it is easy to observe on examining the above 
 table that it is stemmed wine that should be read in place of non-stemmed. 
 
 t There is a contradiction between this conclusion and the figures of the 
 table, but it is without importance, the result being in both cases very slightly 
 different. 
 
72 WINE-MAKING IN HOT CLIMATES. 
 
 " As the advantage resulting from the aeration of the 
 vintage, and the expulsion of foreign matters and germs of 
 noxious fermentation, may be realized without stemming, we 
 may conclude that for wine made from heavy-bearing kinds 
 of the south-west, of which the three experimented upon 
 are the most important, that this practice is useless, if not 
 actually injurious." 
 
 We concur entirely with the views expressed by Vincens, 
 taking exception however to those referring to altered (in- 
 jured) vintage, and for special vinifications, such, for in- 
 stance, as the vinification of red wine with grapes partly 
 drained for white wine. 
 
 Later on we will discuss these exceptional cases when 
 describing the manufacture of white wine from red grapes. 
 
 THE VATT1NG. 
 
 The squashed vintage delivered from the crushers is fer- 
 mented in vats. For the fermentation to take place in a 
 satisfactory manner, so that the resulting wine will possess 
 the maximum qualities compatible with the nature of the 
 vintage, it is necessary: 
 
 First That the vinous ferment which causes the pheno- 
 mena be the only one at work in the must. 
 
 The presence of healthy, vigorous, and abundant yeast is 
 indispensable to attain this object. 
 
 The aeration of the crushed vintage is an important factor 
 in the multiplication of the ferment. 
 
 Second That the transformation be effected as rapidly as 
 possible. The rapidity of the work depends on the life of the 
 ferment, which will only furnish its maximum yield if the 
 chemical and physical conditions of the liquid are suitable. 
 
 Third That the solid parts of the grape be sufficiently 
 in contact with the liquid part to enable it to dissolve the 
 necessary substances. This is obtained by various methods 
 and special manipulations. 
 
 AERATION OF THE VINTAGE. 
 
 Let us assume the grapes to be introduced into the vat 
 without being crushed, and the air in the vat replaced by an 
 inert gas, such as nitrogen. If we thea prevent the access 
 of any air and crush the grapes in situ, it would be noticed 
 that the phenomena following the crushing were not at all 
 
VILIFICATION. 73 
 
 comparable to what takes place under ordinary circum- 
 stances^ The fermentation would be very difficult to start, 
 and if it started at all would have no energy and probably 
 be the seat of a great many alterations. If this be so it 
 means that the germs of the ferments existing on the sur- 
 face of the grape have only had at their disposal the small 
 quantity of oxygen remaining in the grape, and that it is 
 indispensable for the yeasts to have at their disposal a 
 quantity of air sufficient for their normal development. It 
 is not so for all the micro-organisms existing on the surface 
 of the grape, for a number of these find the conditions con- 
 genial, and succeed in changing the must into a liquid 
 having nothing in common with wine. 
 
 Let us suppose again a vintage crushed in contact with 
 the air, but with a limited aeration, such as would result 
 from crushing grapes in a bottle almost full, and closed 
 before crushing so as to prevent the access of any additional 
 air. The fermentation would start and become rather active. 
 The activity may be measured by the amount of carbonic 
 acid produced in a given time. If we study this fermenta- 
 tion we will see that it diminishes rapidly, although there is 
 a great quantity of sugar left, showing that the ferment still 
 has food left, and that the cells of the ferment require after 
 their first work a certain quantity of air to restore them to 
 activity and enable them to multiply. 
 
 This statement made by Duclaux, and deduced from 
 Pasteur's classical experiments, is easy to verify. 
 
 If the above must is racked in contact with air it will be 
 seen that disengagement of gas increases at once. Aeration, 
 we therefore maintain, is not only useful but absolutely 
 indispensable to enable the germs on the grape skin to 
 develop, and it is necessary to restore the ferment while the 
 fermentation is proceeding, to enable the complete conversion 
 of the sugar to take place. 
 
 The first aeration takes place during the crushing, and it 
 is the imperfect aeration in cylinder crushers which causes 
 the inferiority so often noticed in wines so made, as compared 
 with those from crushing by the feet. In the latter case the 
 vintage remains longer in contact with the air, consequently 
 the aeration is more perfect. 
 
 In some districts (Bordeaux) they even go further. The 
 vintage is thrown up in the air with shovels, before being 
 placed in the vat. 
 
74 WINE-MAKING IN HOT CLIMATES. 
 
 Does this mean that we must place the mechanical 
 crushers aside and return to ancient methods ? 
 
 Certainly not. Sufficient aeration may be obtained with 
 machines. Some machines, such as the aero-crusher, effect 
 the aeration during the crushing, in other cases, especially 
 if the grapes have to travel in a long and open shute, it 
 produces the same result. The paddles of the stemmers also 
 have an aerating effect. We may also, immediately after 
 the crushing, pump the must over the head (marc floating 
 in the vat), being careful to spread it all over. This practice 
 is quite sufficient to introduce into the must the quantity of 
 oxygen necessary for a good start. The pumping over of 
 the must may be repeated if necessary, and will prolong the 
 fermentation until the sugar has entirely disappeared. 
 
 Stemming, as we have seen, has not got a very direct 
 influence on the quality of the wine, but it acts indirectly 
 through the intense aeration it furnishes, and many think it 
 is the only benefit we can get from the adoption of this 
 practice in the South of France. 
 
 We cannot do better than support our views by those of 
 Pasteur. The following is his opinion, built on the irrefut- 
 able experimental methods everybody grants to that scientist, 
 taken from his Etudes des Vins: 
 
 u I have noticed that when musts are exposed to contact 
 with the air in a shallow vessel for many hours and stirred 
 that fermentation is much more active than with non-aerated 
 musts. The fact that aeration produces such apparent 
 effects even during fermentation, while the liquid is already 
 charged with carbonic acid and alcoholic ferments, is worthy 
 of attention." 
 
 Pasteur describes experiments which leave no doubt on 
 that subject, and which show conclusively that non-aerated 
 must produces more acid wines than those aerated. 
 
 To any one who reads between the lines, abnormal increase 
 of acidity is not a good sign, but rather a sign of defective 
 fermentation, for the increase of acidity is generally due to 
 the formation of volatile acids so characteristic of diseased 
 wines. 
 
 Apart from this, the aeration of the vat has a very bene- 
 ficial influence on the ultimate preservation of the wine. 
 
 We have no experiments to support this fact, as convincing 
 as those of Pasteur, but it seems logical, and many authori- 
 ties admit it. 
 
VINDICATION. 75 
 
 Ott, an American scientist, lays down the principle that 
 the more abundant the oxygen in the must, the more albu- 
 minoid matters the ferment will absorb, and that the wines 
 resulting will keep better the presence of albuminoid 
 matters in excess in the wine being conducive to diseases. 
 
 Ott's opinion is, we believe, annually confirmed in the 
 vineyards of California, where aeration is a common practice. 
 
 It consists in forcing air by means of a pump to the 
 bottom of the vat, and discharging it in a fine stream through 
 a perforated rose. This operation is repeated each day for 
 ten minutes. The forcing of air through the fermenting 
 must is no doubt a good thing, and tends to the preservation 
 of the resulting wine ; but it has a decided inconvenience in 
 the case of wine required in commerce to be brilliant and 
 frais. 
 
 According to Ott, aeration matures the wine quickly, and 
 gives it that tawny colour so characteristic of old wines. 
 
 We may obtain certain advantages by well-conducted 
 aeration, but it must be well conducted, for it may become 
 injurious if practised to excess and under bad conditions. 
 
 Aeration before the fermentation starts, can never be too 
 thorough or complete. 
 
 When once fermentation has started, we must act with 
 caution, for given with circumspection, the oxygen maintains 
 the life of the various ferment and enables it to work with 
 proper activity. It slightly oxidizes the colouring matter, 
 and gives it a greater facility of dissolution, without modify- 
 ing its tint. If the oxidation is excessive the colouring matter 
 alters and becomes brownish, and loses its fixity in solution. 
 
 This applies specially to fermentation in the South of France 
 and Algeria, where very often the temperature is so high that 
 the ferment dies. Excessive aeration under these circum- 
 stances acts on the colouring matter in a disastrous way. 
 Notwithstanding this great inconvenience aeration must not 
 be rejected, for it still has a marked utility. It allows the 
 complete conversion of the sugar, which is indispensable if we 
 wish to avoid making wine which will certainly be of doubt- 
 ful keeping qualities. 
 
 Eietsch and Herselin* pointed out these advantages in a 
 series of laboratory experiments bearing on apiculatus and 
 ellipsoideus yeasts. 
 
 Proyres Ayricole et Viticole, 1895 
 
76 WINE-MAKING IN HOT CLIMATES. 
 
 They were able to obtain in all the fermentations at high 
 temperatures at 36 C. (97 F.) a more rapid and complete 
 decomposition of the sugar when aeration was used. 
 
 The vine-grower, therefore, is confronted with an unpleasant 
 situation if the temperature of the vat is allowed to rise too 
 high. Without aeration he will obtain wine of uncertain 
 keeping quality, with aeration better keeping wine but less 
 fine will result. 
 
 The maintenance of the temperature of the vat between 
 proper limits is the only way of avoiding this embarrassing 
 situation. 
 
 The process has also many other advantages. We have 
 had an opportunity of making a series of experiments in 
 Algerian cellars on this subject, and these have since been 
 continued in our laboratory in conjunction with F. Chabert, 
 as studies on the different actions of high temperature on 
 alcoholic fermentation. These studies are not yet completed, 
 but allow us to clear up certain obscure points in the above 
 observations. 
 
 We will reproduce, in extenso, these studies, and hope they 
 will prove the absolute necessity for controlling the tempera- 
 ture during fermentation. 
 
 CONTRIBUTION TO THE STUDY OF VINOUS 
 FERMENTATIONS. 
 
 INFLUENCE OF TEMPERATURE. 
 
 (By L. Roos and F. Chabert.) 
 
 The temperature of fermentation plays a part in viuification 
 which recent studies have shown to be so important, that 
 it is to-day a subject of thought for every cenologist. 
 
 The flavour and keeping qualities of wines, depend to a great 
 part on the temperature at which the transformation of the 
 must is made. If it is too low the fermentation does not 
 start, or starts too slowly, for the ellipsoideus yeast does not 
 develop well, and bacterial actions take place which alter 
 the value of the product. If it is too high the wine retains 
 untransformed sugar, which forms a suitable medium for and 
 favours the development of bacteria, which may so alter the. 
 
VINDICATION. 77 
 
 nature of the liquid as to render it unfit for consumption. The 
 natural consequence of this double observation leads us to heat 
 our musts in cold climates, a very old practice justified by ex- 
 perience, and to keep the temperature between given limits 
 in hot regions. 
 
 The study of the various processes of heating or refriger- 
 ating musts, does not come within the scope of this paper. 
 We have simply tried to discover the temperature preferred by 
 the wine yeasts, that is to say, the temperature at which 
 they perform a maximum of work in a minimum time. 
 
 High temperature during fermentation has an unfavorable 
 influence on the resulting wine. It reduces its alcoholic 
 strength, alters its taste, and diminishes its keeping quality. 
 
 The consecutive alterations of fermentations at high tem- 
 peratures are well established, but have according to us, been 
 too generally attributed to the development of micro- 
 organisms, called parasitic, to distinguish them from those 
 which transform the sugar into alcohol. 
 
 Our experiments tend to show that, together with the 
 bacterial action (an indirect result of the excessive tempera- 
 ture) there is another action of the same class, but perhaps 
 less important, attributable to the yeast itself, the. evolutions 
 of which, and its conditions of work, are profoundly modified. 
 
 Our experiments were made on raisin must, during the 
 year, and with fresh grape musts during the vintage of 1896. 
 We did not use yeasts of a special character, but simply took 
 them from the wine lees of the district, making sure, how- 
 ever, that the wine yeasts were self-cultivated. The colonies 
 were obtained in solid gelatine and multiplied in sterilized 
 must. The lees from which we extracted the yeasts came 
 from the environs of Mudaison (Herault) and Saint Laurent 
 d'Aigouze (Gard). 
 
 We tried to keep as far as possible within general viti- 
 cultural conditions, but do not pretend not to recognise the 
 difference there is between laboratory practice and cellar 
 operations. This simply means that we cannot give our 
 results as the exact expression of what takes place in a cellar, 
 but that they are simply land-marks placed on the path of 
 this very complex study. 
 
 Before giving our results, and describing the apparatus 
 used by us, we will briefly summarize the previous work on 
 this subject. 
 
78 WINE-MAKING IN HOT CLIMATES. 
 
 OPINIONS OF VARIOUS AUTHORITIES AS TO THE 
 BEST TEMPERATURE FOR FERMENTATION. 
 
 Chaptal * states that the most favorable temperature is 
 15 R. (66 F.) It languishes below that temperature, 
 becomes too tumultuous above it, and if the temperature is 
 too high or too low does not take place at all. 
 
 According to A. Gautier f the most favorable temperature 
 is between 28 and 32 C. In no case should it fall below 
 18 C. or exceed 36 C. Once that extreme maximum is 
 reached the glucose not only forms .alcohol, but also other 
 products, and the rapid disengagement of carbonic acid 
 carries away a notable quantity of alcohol. { 
 
 Gautier points out already the formation of " other pro- 
 ducts " is a result of fermentation at high temperature. Our 
 experiments verify this opinion, for they show in the ferment- 
 ing liquid the existence of products, not yet well defined, but 
 exerting a distinct action. 
 
 Prof. Bouffard fixes 25 C. as the temperature required 
 for a good fermentation. " The temperature of 20 C. which 
 sometimes cannot be exceeded in Bourgogne and that of 
 35 C. always reached in Algiers are unfavorable. Wines 
 made between 20 and 32 C. have more suavity in perfume 
 and taste. Those obtained between 30 and 35 C. are flat, 
 less perfumed, and possess foreign tastes due to the develop- 
 ment of parasitic ferments." 
 
 L. RougierJ in his Manuel Pratique, also studies the 
 influence of temperature. Below 8 or 10 C. fermentation 
 is impossible. The activity of the ferment increases little by 
 little as the temperature rises to 25 or 30 C., above 40 or 
 45 C. the fermentation tends to stop before the sugar is 
 completely transformed. When the temperature gets over 
 30 C. the carbonic acid carries away a certain quantity of 
 alcohol and volatile principles constituting the bouquet.lf 
 
 * L'Art de foire le Vin, p. 94, by Count Chaptal. 1819. We must draw 
 attention to the correspondence between the Centigrade and Reaumur 15 
 Reaumur, 1870 Centigrade. 
 
 t Dictionnaire de Chemie de Wurtz. Art. Vin. 
 
 + We will see that if a notable quantity of alcohol is carried away it is to be 
 attributed to the elevation of the temperature, and not to the rapidity of the 
 evolution of gases, which, on the contrary, become slower. 
 
 Role de la Chaleur et du Froid dans la Vinification. Progres Agricole et 
 Viticole. 1891. 
 
 |! Manuel Pratique de la Vinijication. L. Rougier, p. 25. 3rd Ed. 1895. 
 
 IF This remark corroborates Prof. Bouffard's opinion above given, that wines 
 made at high temperatures are deficient in perfume. 
 
VINDICATION. 79 
 
 Dr. Frederic Cazalis * quotes the experiments of Miiller- 
 Tlmrgau. These experiments show that " the fermentation 
 of a must between 9 and 36 C. proceeds so much the more 
 rapidly, and with more bubbling, as the temperature is higher, 
 but past that point it stops the more rapidly, leaving a part 
 of the sugar unconverted, as the temperature is higher." 
 Cazalis notes afterwards the considerable influence the tem- 
 perature has on the yield in alcohol, quoting the following 
 figures : 
 
 Fermentation at 9 C. ... 17-29' alcohol by volume 
 18 C. ... 15-09,, 
 27 C. ... 12-23,, ,, 
 36 C. ... 8-96,, 
 
 These results, exact no doubt under the conditions of the 
 experiments of Miiller-Thurgau, cannot be generalized. The 
 factor time, is missing from the table, and it is one of the most 
 important. If we may admit the accuracy of the results with 
 the Rhine yeasts, when treated in laboratories, it is easy to 
 oppose against their generalization the fact well known to the 
 vignerons of the South of France that we may easily obtain 
 up to 10 or 11 per cent, of alcohol at temperatures over 36 C. 
 
 Dr. Fred. Cazalis concludes that the temperature for a good 
 fermentation lies between 15 and 25 C. Prof. Miiller- 
 Thurgau noticed that fermentation ceases between 25 and 
 36 C. before all the sugar is transformed into alcohol, because 
 " the alcohol at such a high temperature acts upon the fer- 
 ment, and even small amounts can arrest its activity."! We 
 admit this action of the alcohol but only as one of the factors 
 causing the stoppage of fermentation. 
 
 We will show by experiments that the presence of alcohol 
 is not the only cause retarding the work of the ferment. 
 
 If it were possible, it would be sufficient to bring the liquid 
 back to a proper temperature to see the yeast regain its 
 former activity, but this does not happen. The fermentation 
 only proceeds slowly, and is not even sensibly increased by the 
 addition of fresh yeast taken from another vat in full activity. 
 
 U. GayonJ gives as a limit 27 to 38 C., which should not 
 be exceeded in any case if we do not wish to see the must 
 
 * Traite Pratique de I' Art de faire Ic Vin. Dr. Frederic Cazalis, p. 144. 
 Montpellier. 1890. 
 
 f This is only true for quantities of alcohol varying between 8 and 10 per 
 cent., and for temperatures exceeding 36 C. (R>os and Chabert.) 
 
 t U. Gayon, Rapport sur la Vinification dans Us Annies Chaudcs. Bordeaux, 
 1895. 
 
80' WIXE-MAKIXG IX HOT CLIMATES. 
 
 attacked by disease ferments, and especially by the mannitic 
 ferment.* It is the toxic action of the alcohol, the absence 
 of oxygen, and the high temperature of 40 C. which para- 
 lyzes the ferments. 
 
 Miintz and Rousseaux f define the " critical point" as the 
 temperature the yeast cannot support without suffering ; if 
 that temperature is exceeded by a slight degree, its influence 
 on the course of the fermentation has an important influence. 
 This critical point is characterized by the fact that the yeast, 
 still living if that point is just reached, dies directly it is ex- 
 ceeded. We can enable the ferment, therefore, to recover by 
 refrigeration, provided that the critical point is not exceeded. 
 Should it be exceeded and the yeast destroyed, nothing can 
 be done. These authors give an instance, the critical point 
 being supposed to be between 38 and 40 C. 
 
 We admit with Miintz and Rousseaux a morbid state of the 
 yeast at high temperature, increasing as the temperature 
 exceeds 35 C., we admit also a kind of critical point: 38 to 
 40 C., which should not be exceeded if we wish to bring the 
 ferments back to activity by refrigerating ; but we think 
 that 38 to 40 C. conduces only to a more accentuated morbid 
 state, and not to the death of the ferment, as this only occurs 
 at a high temperature, for when sown in fresh must these 
 yeasts start fermenting regularly again. 
 
 H. Dessoliers,J in a study on vinification in hot countries, 
 explains at length the influence of temperature on fer- 
 mentation. " The temperature is a dominant and essential 
 element in fermentation. The duration of fermentation will 
 be so much the greater that the must has been the longer 
 exposed to a high temperature (40 to 42 C.). The duration 
 of the action of the high temperature must be taken 
 into consideration more than the temperature itself." Des- 
 soliers shows that high temperature produces sweetish wines 
 liable to alterations, and quotes an observation due to 
 Maerker, who asserts that yeasts do not multiply at tempera- 
 tures over 28 C. This statement cannot be accepted without 
 reserve. At 35 or 40 C. the yeasts multiply, not under 
 favorable conditions perhaps, but nevertheless they multiply. 
 
 * Gayon points out that the mannitic ferment starts during the true fermen- 
 tation. We have shown that this disease easily develops in a sweet wine at 40 
 C. L. Roos, Journal de Pharmacie et de Chimie, 1892. 
 
 t Miintz and Rousseaux. Etudes sur la Vinification dans le Roussillon, 
 faites aux Vendanges de 1894. Bulletin du-Ministere de V Agriculture, 1895, 
 p. 1208. 
 
 + H. Dessoliers, Vinification en Pays Chauds. Alger. 1894. 
 
VERIFICATION. 81 
 
 Dessoliers states that yeast cannot germinate if it has 
 been submitted to too high a temperature. We have, 
 however, shown above that it can germinate normally if 
 placed in new must. 
 
 One of us, taking into consideration numerous experi- 
 ments made on yeasts from many different countries, fixed 
 the maximum vitality of the vinous ferment, whatever species 
 it may belong to, at between 28 and 32 C. At 20 C. the 
 activity is very slow. At 40 C. it is nil. At 45 C. it dies, 
 or is of no further use.* " The very best temperature is 
 30 C., and the must cannot go much above or below this limit 
 without becoming liable to bacterial diseases, those made at 
 the higher temperature becoming most liable. The vinous 
 yeast may be killed at temperatures insufficient to kill other 
 ferments. At high temperatures the yeasts eliminate 
 products detrimental to the wine, which may even render the 
 must sterile, although still containing 'sugar, and the other 
 conditions apparently seeming favorable ; or the yeast in 
 full activity develops badly, or perhaps not at all."f 
 
 To summarize, different authorities agree that in high 
 temperature lies the most important cause of the defects of 
 wines made in hot regions. The sugar they often contain, 
 through the fermentation not being completed, is a favorable 
 ground for the development of bacterial diseases. 
 
 The numerous applications of refrigeration to musts 
 confirm this opinion of scientific authorities. 
 
 METHODS AND APPARATUS EMPLOYED. 
 
 Exact estimations of acidity calculated as sulphuric acid 
 were made for all the musts experimented upon. 
 
 Reducing Sugar. We used, for the estimation of this, the 
 ordinary ciipro-potassic solution, but substituting the elec- 
 trolytic determination of the precipitated copper for the 
 volumetric method, relying on the disappearance of colour. 
 The musts, although diluted, were rich enough for the 
 slightest divergency in measurement of the volume of liquid 
 in the burette, corresponding to the end of the reaction to 
 
 * L. Roos. Principes generaux de la vinification en rouge. Proyres agricole 
 et viticote, 1894. 
 
 t L Roos, Etudes sur la vinification en pays chauds. Revue de Viticulture, 
 1894. ' 
 
 10649. F 
 
82 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 result in notable errors. The musts were examined in 
 Laurent's polarimetre. We used Salleron's mustimetre to 
 obtain approximate indications. 
 
 Acidity. Determined by titrated lime water. The wines 
 resulting were more closely examined. We determined : 
 
 Reducing Matters, always expressed as glucose, estimated 
 by the ordinary method, that is, decoloration of a cupro- 
 potassic solution by the wine previously treated with sub- 
 acetate of lead. 
 
 Alcohol in Volume, per cent, determined by distillation, and 
 density by pyknometer, this being the most accurate method. 
 Acidity is expressed as sulphuric acid per litre. 
 Total Nitrogen (with the exception of nitrogen existing 
 in the shape of pyridine compounds) was estimated by the 
 Kjeldahl process. 
 
 By the way, we draw attention to an experimental point. 
 It is often difficult to obtain a complete decomposition 
 without loss, when examining wine rich in sugar. By evapo- 
 rating on a water bath from 50 to 100 c. c. of wine in a small 
 
 flask of 200 to 300 c.c., 
 and adding to the residue 
 a few drops of concen- 
 trated sulphuric acid, a 
 spongy carbonaceous 
 mass is formed well 
 adapted to complete 
 decomposition, without 
 producing the violent 
 frothing so liable to oc- 
 casion trouble or loss. 
 
 The fermentations 
 were conducted at four 
 different temperatures, 
 including the maximum 
 and minimum generally 
 observed in our regions, 
 25, 30, 35, and 40 V. 
 These temperatures 
 were maintained constant 
 by meansof the apparatus 
 
 Fig. 14. -Flask submerged by a lead ring, con- shown in Fig. 14. The 
 taining the must-C, circular gas burner ; L, rCCCptacle COntainS Water 
 Liebig bulbs, containing sulphuric acid; R, 
 thermo-regulator ; S, tripod ; T, thermometer. 
 
VINDICATION. 
 
 83 
 
 X 
 
 in which the thermo-regulator is placed. The regulator is 
 influenced to a certain extent by the pressure of the gas 
 supply. We were, therefore, obliged to interpose between it 
 and the gas supply a Moitessier pressure regulator. 
 
 A flask, B, of two litres capacity, containing 1-5 litres of 
 must, kept submerged by a lead ring, supported in the tank 
 on a wood-lead ring, and closed with a doubly perforated 
 cork. Through one hole a thermometer, T, passed, through 
 the other an exit tube, connected with a Liebig's absorption 
 apparatus, L, where the alcohol and the water vapour 
 escaping were caught. 
 
 The quantities of gas disengaged were measured either by 
 the balance, or the self-registering gas disengagement machine 
 of Houdaille.* In either case the temperature of the must 
 inside the flask and of the surrounding water were recorded 
 
 every other hour. 
 In the first case the 
 weighings were 
 made at even inter- 
 vals. In the second 
 case the carbonic 
 acid was measured 
 by the Houdaille 
 self-registering ap- 
 paratus, of which 
 we will now give a 
 short description, 
 Fig. 15. 
 
 It consists of a kind of gasometer, G, with two compart- 
 ments, C and C, plunged in water, oscillating on a horizontal 
 axis in such a way that, moving round the pivot under the 
 pressure of the gas, one of the compartments may empty 
 itself while the other is filling. Each oscillation, by means 
 of a very simple system of levers, prints a point on the 
 cylinder moved by clock-work. 
 
 The cylinder may move normally in the direction of the 
 lever; in front -of it is a groove, D, and as it revolves once 
 in twelve hours, it suffices for a small lateral displacement 
 of the cylinder, to avoid the overlapping or super-position of 
 the points, and therefore allows the continuous observation 
 
 * Houdaille. Sur un appareil enregistreur des fermentations alcooliques. 
 Annales dt VEcole d* Agriculture dc Montpellier, 18S7- 
 
 F 2 
 
 Fig 1 . 15. G G', compartments of the gasometer, G; D, 
 groove ; I, cylinder ; P P l , counterpoise ; R, trough 
 containing the water ; T, tube leading gas to register. 
 
84 WINE-MAKING IN HOT CLIMATES. 
 
 of a few days' fermentation. We used a four-compartment 
 register, one being applied to each fermentation. 
 
 This apparatus works very accurately in the case of a gas 
 insoluble in water, but is not so satisfactory with carbonic- 
 acid. The solubility of carbonic acid in water is an obstacle 
 to its perfect action. This might be avoided in using a liquid 
 in which carbonic acid is insoluble. 
 
 It is very difficult to find such a liquid ; glycerine is the 
 only one not exerting a solvent action, but it has the dis- 
 advantage of being too viscous, and diminishing the mobile 
 action of the compartment. 
 
 We endeavoured to render the solution of the carbonic acid 
 almost nil, by maintaining the water in the trough constantly 
 saturated with carbonic acid, by interposing an atmosphere 
 of that gas between the water and the atmosphere. 
 
 With this object each of the com- 
 partments received a slow current 
 of carbonic acid, obtained by a 
 regular flow of alkaline carbonate 
 into dilute sulphuric acid, the two 
 bottles being placed one above the 
 other, F F, fitted with a Mariotte 
 tube, Fig. 16. 
 
 A board, in which is bored a hole 
 to allow the movement of the rod 
 connected 'with the compartments, 
 
 shelters the SUrfaCC of the Water 
 
 o K te p againstdraughts which might sweep 
 tu P befo7 t ie S 'c2SnTc ; an: wa 7 ^ liberated gas. This slight 
 hydride. modification enabled us to obtain 
 
 with the Houdaille apparatus results quite comparable with 
 those obtained by weighing. 
 
 We will, later on, describe the device by which we 'tried 
 to measure the quantities of alcohol carried over mechani- 
 cally by the carbonic acid. 
 
 STUDY OF FERMENTATIONS. 
 
 At 25 G. the start is very slow, the froth only appears on 
 the fourth day, although the disengagement of gas shows 
 the fermentation to be already well established. The liquid 
 is rendered turbid by the yeasts, and the sulphuric acid in 
 the Liebig bulbs is coloured brown by the gas. 
 
VINDICATION. 85 
 
 At 30 0. very rapid start, very regular course, slacking 
 down before the sugar is completely transformed, the liquid 
 is very turbid, and the sulphuric acid in the bulbs is coloured 
 more intensely brown than before. 
 
 At 35 C. the start is also very rapid, and the activity is 
 very regularly maintained as long as the alcoholic strength 
 is below a certain limit. It slacks off sooner than* the fer- 
 mentation at 30 C. and leaves more sugar tin transformed. 
 The liquid is very turbid at the beginning, and becomes clear 
 after the yeast diminishes its activity, the sulphuric acid in 
 the bulbs becoming very intensely coloured. 
 
 At 40 C. the start is not very noticeable, and the fermenta- 
 tion is always very slow. The liquid did not get very turbid, 
 although there was an abundant deposit of yeast at the 
 bottom of the flask. A great part of the sugar remained 
 undecomposed. The sulphuric acid in the bulbs becomes 
 only slightly coloured. 
 
 The fermentations which are most active at the beginning 
 are, in order of rapidity 35, 30 C.; sometimes, however, that 
 at 30 C. takes the lead, but in most cases the fermentation 
 at 35 C. overtakes it ; this only happens at the commence- 
 ment and for a short time, after which they keep at the same 
 rate. 
 
 The fermentations at 25 and 40 C. start with more diffi- 
 culty, the latter being always slower and less active. 
 
 Between the fermentations at 25 and 30 C., the difference 
 of the rate of activity can only be observed at the beginning. 
 The start is more difficult at 25 C., but when once the fer- 
 mentation has commenced it proceeds very regularly with 
 much greater loss of weight than that of the fermentation at 
 30 C. In such a way that by prolonging the experiment 
 we arrive at the decomposition of the sugar quite equally in 
 both flasks. While by that time the flasks at 35 and 40 C. 
 have already stopped fermentation. 
 
 A constant and remarkable fact noticed in our experiments 
 is that, with the same must, the higher the temperature rises 
 the deeper the colour becomes. We can evidently not put 
 this down to oxidation of the colouring matter of the must, 
 for it is isolated from contact with the air by the Liebig 
 bulbs. In the cases where we tried the action of the air 
 during fermentation, we observed this modification of colour 
 before the introduction of air, and did not observe any 
 influence of this kind due to the air in that operation. 
 
86 WINE-MAKING IN HOT CLIMATES. 
 
 The sulphuric acid in the Liebig bulb becomes differeutly 
 coloured, the density of the brown colouring being deeper for 
 the fermentation at 35 C., a little less for the fermentation 
 at 30 C. This coloration seems to depend on two factors, 
 the temperature and the rapidity of the evolution of gas, and 
 this explains the coloration of the acid corresponding to the 
 flasks fermenting at 40 C., for if in this case the tempera- 
 ture is higher, there is only a very slight quantity of car- 
 bonic acid passing through the sulphuric acid bulbs. 
 
 The brown coloration turns to a very fine pink on the 
 addition of water to the sulphuric acid. We thought that 
 the turning to pink was peculiar to dry grape musts (raisin 
 must), but fresh grape musts gave the same results. 
 
 INFLUENCE OF TEMPERATURE ON THE YIELD OF 
 ALCOHOL. 
 
 Two cases will be considered, the absolute yield of alcohol 
 independently of the quantity of sugar decomposed, and the 
 relative yield that is to say, the ratio between the alcohol 
 obtained and the sugar which has disappeared. 
 
 In both cases the yield in alcohol is less as the tempera- 
 ture is higher. In absolute yield this result only holds if we 
 consider fermentations lasting more than ten days ; below 
 this limit the fermentations at 25 C. furnished less alcohol 
 than that at 30 C., but the relative yield always remains 
 greater. 
 
 In short, tor a normal duration of eight days the fermenta- 
 tion at 30 C. is the best, then follow in order 25, 35, 40 
 C., the latter always taking much longer than the others. 
 If we allow the fermentation at 40 C. to remain undisturbed, 
 it continues to gain in alcohol, but very slowly, and then only 
 under the influence of a fermentation, the exterior characters 
 of which are very different from those of an ordinary fer- 
 mentation. Two of our experiments (on must from fresh 
 grapes), which did not contain: One, 4 per cent, of alcohol on 
 the seventh day, and the other, 6 per cent, on the tenth day, 
 showed for the first 9*5 per cent, two months after, and the 
 other 6*4 per cent, after eighteen months. 
 
 We have never obtained 47 per cent, of alcohol per 100 of 
 sugar decomposed, considered as a practical yield, although 
 we have closely approached it. 
 
VILIFICATION. 87 
 
 This might be because our temperatures were too high 
 even that of 25 C. 
 
 The yield of 47 per cent, which can be obtained in cold 
 regions is never obtained to our knowledge in warm regions, 
 and we think that the measurement of the sugar, based on 
 the transformation of that body by fermentation, must be 
 done in order to be exact, when the operation is effected at a 
 very low temperature, and during a long time. 
 
 The following tables summarize the analytic results 
 obtained on some of our wines, and give the differences 
 observed in relative and absolute value : 
 
 RAISIN MUST, No. 1. 
 
 Reducing matters ... ... 174 grammes per litre. 
 
 Mustimetre ... ... 170 
 
 Polarimetric deviation ... 22 (sugar degree) 
 
 25 C. 30 C. 35 C. 40 C. 
 Alcohol in volume, per cent. ... 10-1 9'7 9-2 2*1 
 
 Alcohol in weight, per litre .,. 80-8 77'6 736 16'8 
 Sugar remaining ... ... 2'0 2*5 4'5 * 
 
 Sugar transformed ... ... 172*1 171-6 169'6 
 
 Ratio of alcohol to sugar trans- 
 formed ... ... 46-94 45-22 43'39 
 
 Difference from the practical 
 
 yield of 47 per cent. ... 0-06 178 3-61 
 
 Difference from the theoretical 
 
 yield of 48-5 per cent. ... 1'56 3'28 5-11 
 
 Quantities of alcohol condens- 
 able hypothetically, in abso- 
 lute volume ... ... 1-57 3-17 4-70 
 
 Quantities of alcohol condensable 
 hypothetically, in weight, per 
 litre ... ... ... 1-42 2'54 3'76 
 
 RAISIN MUST, No. 5. 
 
 Reducing matters ... ... 174*5 grammes 
 
 Mush'metrc ... ... ... 167 '0 ,, 
 
 Polarimetric deviation ... 32'4 (sugar degree) 
 
 
 25 C. 
 
 30 C. 
 
 35 C. 
 
 40 C. 
 
 Alcohol in volume, per cent. 
 
 9-9 
 
 9-7 
 
 9-1 
 
 7-3 
 
 Alcohol in weight, per litre 
 
 79-2 
 
 77-6 
 
 72-8 
 
 58-40 
 
 Sugar remaining 
 
 3-0 
 
 3-0 
 
 100 
 
 41-0 
 
 * An accident prevented the determinations being made for the fermenta- 
 tion at 40 C. 
 
8 WINE-MAKING IN HOT CLIMATES. 
 
 RAISIN MUST, No. 5 continued. 
 
 25 C. 30 C. 35 C. 40 C 
 
 Sugar transformed ... l7l'5 171'5 164-5 133-5 
 
 Ratio of alcohol to sugar 
 
 transformed ... ... 46' 17 45-25 44'25 42-24 
 
 Difference from the practical 
 
 yield of 47 per cent. ... 0'83 l'6o 2'65 4-66 
 
 Difference from the theoretical 
 
 yield of 48-5 per cent. ... 2'43 3'25 4'25 6'26 
 
 Quantities of alcohol con- 
 densable, hypolhetically, in 
 absolute volume ... 2'40 3'27 3*86 4'57 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 weight, per litre ... 1-92 2'62 3'10 3'65 
 
 RAISIN MUST, No. 6. 
 
 Reducing matters ... ... 247 grammes 
 
 Mustimetre ... ... ... 247 
 
 Polarimetric deviation... ... - - 28'2 U (sugar degree) 
 
 25 C. 30 C. 35 C. 40 C. 
 
 Alcohol in volume, per cent. in 10'6 9-3 * 
 
 Alcohol in weight, per litre 88 '8 84'N 74-4 
 Sugar remaining ... 56-8 63'2 83'3 
 
 Sugar transformed ... 190-2 183'8 163-7 
 
 Ratio of alcohol to sugar 
 
 transformed ... ... 46*68 46- 13 45'44 
 
 Difference from the practical 
 
 yield ... ... ... 0'32 O87 1-56 
 
 Difference from the theoretical 
 
 yield ... ... ... 1-82 2'37 3'06 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 
 absolute volume ... 2'02 2'51 2-84 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 weight, per litre ' ... 1*62 2'01 2'28 
 
 After eight days, even when the flask had returned to 
 the temperature of the surrounding air, the fermentation 
 did not start, which leads us to think that the temperature 
 of 40 C. had killed the yeast. We only noticed this in one 
 instance. 
 
 * The fermentation at 40 C. did not move appreciably. This was due, no 
 doubt, to the great saccharine richness of the must. 
 
VINDICATION. 
 
 89 
 
 FRESH GRAPE MUST (TERRET- 
 
 JKb. 
 
 Reducing matters 
 Mustimetre 
 Polarimetric deviation 
 
 Alcohol in volume per cent.* 
 
 Alcohol in weight, per litre ... 
 
 Sugar remaining ... 
 
 Sugar transformed 
 
 Ratio of alcohol to sugar 
 transformed 
 
 Difference from the practical 
 yield ... 
 
 Difference from the theoretical 
 yield ... 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 absolute volume 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 weight, per litre 
 
 FRESH GRAPE MOST 
 
 Reducing matters 
 Mustimeire 
 Polarimetric deviation 
 
 Alcohol in volume, per cent. 
 
 Alcohol in weight, per litre ... 
 
 Sugar remaining ... 
 
 Sugar transformed ... 
 
 Ratio of alcohol to sugar 
 transformed 
 
 Difference from the practical 
 yield ... 
 
 Difference from the theoretical 
 yield ... 
 
 Quantities of alcohol con- 
 densable, hypoihetically, in 
 absolute volume 
 
 Quantities of alcohol con- 
 densable, hypothetically, in 
 weight, per litre 
 
 BOURRET AND PlCQUKPOUL), 
 
 8. 
 
 190 grammes. 
 
 190 
 
 40 (sugar degree). 
 
 25 C. 30 C. 35 C. 40 C. 
 
 10-9 10-9 9-6 9-3 
 
 87-20 87-20 76-80 74'4 
 
 2-50 2-00 22-90 27'0 
 
 187-50 188-00 167-10 163-0 
 
 46-5 46-38 45-96 45*64 
 
 0-50 0-62 1-08 1-36 
 
 2-00 2-12 2=58 2-86 
 
 2-18 2-31 2-48 2-66 
 
 1-04 1-85 1-98 2-1 
 
 (ARAMON), No. 11. 
 
 203-40 grammes. 
 200-00 
 
 37 (sugar degree). 
 
 25 C. 30 C. 35 C. 40 C. 
 
 9-6 7-2 6-1 
 
 76-80 57-60 51-2 
 
 39-15 76-90 86-9 
 
 ... 164-25 126-50 110-5 
 
 46-75 45-50 43-9 
 
 0-25 1-50 3-1 
 
 1-75 3-00 4-6 
 
 1-68 2-15 2-94 
 
 1-34 1-72 2-35 
 
 * The analyses of these wines were made three months after the start of the 
 fermentation. 
 
90 WINE-MAKING IN HOT CLIMATES. 
 
 In this trial the experiment at 25 0. was not made, the 
 analyses were only made one month and a half after the 
 start. 
 
 We see that fermentation left for a few days at a high 
 temperature can only be completed after a long time four 
 months at least, for fermentations that have been submitted 
 to a temperature of 40 C. during ten days. This excessive 
 duration of slow fermentation, seems to depend on the time 
 during which the flask has been submitted to the high 
 temperature ; however, we repeat, one may obtain complete 
 fermentations, giving sound wines, but that result can only 
 be obtained in the laboratory, that is to say, in must 
 previously sterilized and sown with pure yeast. 
 
 INFLUENCE OF THE TEMPERATURE ON THE WORK OF 
 DIFFERENT YEASTS. 
 
 High temperatures, therefore, have a retarding action 
 on the yeasts of the He"rault, which were used in these 
 experiments. 
 
 We tried to ascertain if, as suggested by Marchand, 
 Director of the Experimental Cellar at Mascara, in Algeria, 
 the yeasts suffer more or less at high temperatures, accord- 
 ing to the cold or hot regions they originate from. 
 
 Marchand having studied the working of two yeasts taken 
 from the same cepage, but from different regions, and work- 
 ing in the same musts, noticed that these yeasts could stand 
 very different temperatures, the one originating from the hot 
 district suffering less than the other. 
 
 This observation led us to think that the most favorable 
 temperature found by us for the yeasts of the Herault 
 (30 C.) might be high for yeasts originating from cold 
 climates, and low for those from hot climates. 
 
 To verify this idea, we have made a series of experiments 
 with yeasts from the Rhine, Burgogne, and Herault. But 
 we only obtained the divergent results given in the following 
 table : 
 
 25 C. 30 C. 35 C. 40 C. 
 
 Mudaison yeast ... 105 20 164-00 109-00 85-20 
 
 Bourgogne yeast ... 95-40 140-00 131-20 106-50 
 
 Wolbrath yeast ... 130-98 112-00 112-90 90-00 
 
 These figures do not seem sufficient for rejecting 
 Marchand's theory, for the Rhine and Burgogne yeasts we 
 
VINDICATION. 
 
 91 
 
 used had been reproduced many times in the laboratory, at 
 somewhat high temperatures, which may have enabled them 
 to acquire special resistance. 
 
 If this were so, we may foresee the possibility of creating 
 a race of yeasts capable of withstanding without difficulty 
 the temperature of the South of France, but this is only an 
 hypothesis. 
 
 INFLUENCE OF TEMPERATURE ON THE LOSS OF ALCOHOL. 
 
 We used, to collect the alcohol, the 
 following device, Fig. 17 : The exit 
 tube, the Liebig bulbs having been 
 removed, leads to a bottle, F, containing 
 a small quantity of water ; the vapours 
 not caught by this, pass through a con- 
 denser surrounded by ice. 
 
 The results obtained by this means 
 are not accurate, and not comparable, 
 for there is a condensation of alcohol 
 taking place on the portion of the flask 
 Fig. iv. -F, bottle contain^ projecting above the water bath, and 
 
 the water; R, condenser; 7r <? i i m i i_ J.T 
 
 s, worm ; T, tube carrying therefore cold. Ilie higher the tem- 
 
 fne e nfation lvedduringfer " perature of the liquid, the greater the 
 condensation. 
 
 The quantity of alcohol carried over is subordinate to the 
 rapidity of the disengagement of gas, and the gaseous dis- 
 engagement being equal, is so much the greater as the 
 temperature is higher, for the tension of the vapour of 
 alcohol increases rapidly with the temperature. 
 
 In all our experiments the disengagement of carbonic 
 acid did not differ much between the 25, 30, and 35 
 fermentations, but was very slow at 40 C. As the strengths 
 of alcohol are always greater in the three first fermentations 
 than in the last, we should expect to find more alcohol 
 carried away from the fermentations at 25, 30, and 35 C. 
 than that at 40 C., even considering the high tension of 
 alcohol at 40 C. The following figures calculated for one 
 litre confirm our expectations : 
 
 25 C. 30 C. 35 C. 40 C. 
 
 Raisin must 
 
 Fresh grape must... 
 
 C.C. 
 
 1-3 
 
 1-8 
 
 C.C. 
 
 2-0 
 2-1 
 
 C.C. 
 
 2-1 
 
 2-85 
 
 C.C. 
 
 traces 
 1-5 
 
Raisin 
 must. 
 2-5 
 
 Raisin Terret-Bourret 
 must. Picquepoul. 
 23 3-8 
 
 Aramon. 
 
 2-6 
 
 2-4 
 
 3-8 
 
 4-1 
 
 27 
 
 2-8 
 
 4-1 
 
 4-8 
 
 2-8 
 
 3-0 
 
 4-9 
 
 5-1 
 
 92 WINE-MAKING IX HOT CLIMATES. 
 
 These figures are quite sufficient to show that there is a 
 loss of alcohol through mechanical means. We do not 
 think, however, that this loss is the only cause of the diminu- 
 tion of the yield, but, on the contrary, that the most important 
 cause resides in the incomplete utilization of the sugar. 
 
 INFLUENCE OF TEMPERATURE ON THE TOTAL ACIDITY 
 OF WINE. 
 
 The temperature has a marked influence on the total acidity 
 of wine. Experiments have shown us that the acidity always 
 increases with the temperature. Here are several of our 
 results : 
 
 25 C. . 
 
 30 C. . 
 
 35 C. . 
 
 40 C. . 
 
 We cannot blame for this increase of acidity, parasitic 
 fermentations which are the cause of it in ordinary wines, 
 as our experiments were made with sterilized must, sown 
 with pure yeast ; the only reason we can see, therefore, is that 
 the yeast modifies its work with the temperature, and pro- 
 duces acid substances, as the precipitation of a part of the 
 bitartrate of potash, always greater at low temperature, is 
 insufficient to explain the differences observed. 
 
 ACTION OF TEMPERATURE ON THE YEAST. 
 
 One of us has already shown that it is possible to recog- 
 nise, by microscopical observation, if the yeast has worked 
 at a proper temperature.* 
 
 The morphological differences of yeasts worked at different 
 temperatures are very noticeable. The yeast at 25 C. is 
 turgid, with hyaline and homogeneous protoplasm, and 
 spherical. That at 40 C. is elongated, less regular shaped, 
 and coloured, its membrane seems thick, generally wrinkled, 
 sometimes star-like, a few cells only remaining refractive. 
 
 In a chemically neutral liquid (distilled water), for in- 
 stance, the deformations are still more marked, the wrinkles 
 distorted and pigmented. an appearance common with yeast 
 
 * L. Roos. Vinification en pays chauds. 
 
PLATE II. 
 
 Wine Yeast of the Herault working at 25 C. 
 
 Wine Yeast of the Herault working at 40 C. 
 
VINDICATION. 93 
 
 fermented at 40 C. If after being washed, the yeast is 
 placed in distilled water, after having been submitted for 
 eight days to a temperature of 40 or even 25 C., there is also, 
 apart from the special action of the temperature, that of the 
 complete lack of nutritive substances in the liquid ; the yeast 
 produces endogenous spores (Rees spores) at both 25 and 
 40 G. 
 
 Therefore, the temperature has an action on the shape of 
 the yeast in the must, sufficient to be detected under the 
 microscope. It is rational to think that these morphological 
 appearances are the exterior manifestations of a morbid 
 state, the limit of which causes the death of the yeast. 
 
 Riestch and Herselin state that in two series of experi- 
 ments made with Musigny yeast, the yeast, died, after nine 
 clays' fermentation, at 36 C. 
 
 Miintz, who we have already quoted, asserts that the 
 morbid state is at 37*5 C., which he calls the critical point. 
 
 Our experiments lead us to a different opinion. Our 
 yeasts did not die at 40 C., even after remaining ten days in 
 the must at that temperature. Some have even been kept 
 at 42 C. without dying. 
 
 It is evident that if we consider as the death of the 
 ferment, the fact that the must brought down to a proper 
 temperature cannot start fermentation again, we agree 
 with the above authorities, for it is a fact that over- 
 heated fermentations brought down to lower temperatures 
 will not start again. This is not due to the death of 
 the ferment, but to the impossibility of developing in the 
 liquid in which it is. 
 
 To strengthen this opinion, we may mention that we have 
 always obtained active yeast cultures by sowing them in 
 new must, even after they had reached the temperature ot 
 40 C. It does not seem possible to us to fix a limit to the 
 temperature at which yeast is killed, for the composition of 
 the liquid itself is an important factor advancing or 
 retarding this limit. 
 
 INFLUENCE OF THE TEMPERATURE ON THE QUANTITY OF 
 
 NITROGEN. 
 
 Under ordinary circumstances fermentation does not take 
 place without the yeast, which absorbs from the liquid the 
 nitrogenous principles necessary to its constitution, elimi- 
 nating nitrogenous products. It is a general observation of 
 
94 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 Schutzenberger that the elimination of nitrogenous matters 
 increases when the yeast is under unfavorable conditions, 
 
 It appeared to us that the influence of high temperature, 
 which determines the morbidity of the yeast, might also 
 determine a greater elimination of nitrogen, for we noticed 
 in our fermentations that, generally speaking, starting from 
 the same must, the wine obtained is so much the richer in 
 nitrogen as it has been fermented at a higher temperature. 
 
 Nitrogen, per Litre 
 
 25 C. 
 
 30 C. 
 
 35 C. 
 
 40 C. 
 
 
 . 
 
 
 Raisiu must ... 
 
 0-265 
 
 0-322 
 
 0-490 
 
 Terret-Bourrot and Pic- 
 
 
 
 
 quepoul 
 Araraon 
 
 0-11,5 0-115 
 0-112 
 
 0-120 
 0-193 
 
 0-135 
 0-183 
 
 Carignan 
 
 0-187 
 
 ... 
 
 0-205 
 
 Experiments made by Miintz on this subject have attracted 
 scientists' attention. He noticed that wines obtained at 40 C. 
 contain more ammouiacal salts than those made at tempera- 
 tures below 37 G. But there is this great difference between 
 the experiments made by Miintz and ours, that his bear only 
 on ammoniacal salts, and ours on more complex compounds ; 
 and, what is more, he attributes the increase of ammoniacal 
 salts to the destruction of. the nitrogenous molecules by 
 the yeast, and that the yeasts themselves can become the 
 prey of micro-organisms. 
 
 In our experiments nothing of the kind could happen, 
 for, we repeat, we used must sown with pure yeast ; the 
 yeast, far from producing ammoni.i, would, on the contrary, 
 have used all the ammonia that might have been -in the 
 must. 
 
 We have found traces of ammonia only in wine fermented 
 at high temperatures, while Miiiitz found it in wines ferment- 
 ing at a normal temperature. 
 
 It is therefore a fact, not before stated, that high 
 temperatures produce wines rich in complex soluble nitro- 
 genous compounds. 
 
 What is the nature of this nitrogenous matter ? We can 
 only offer a suggestion. We think that the sterility 
 
VINDICATION. 95 
 
 acquired by the must ought to be attributed, partially at 
 least, to these nitrogenous bodies. 
 
 The result of practical observations made in Algeria 
 shows that fermentations, languishing at 40 and 42 C., 
 completely stop and cannot start again, when brought back 
 to a low temperature. 
 
 Two explanations may be advanced first, the death of 
 the yeast ; second, the liquid has become toxic, and there- 
 fore either unfer men table or only fermentable with difficulty. 
 
 We have already seen that at 40 C. the yeast was still 
 living. We have sown new must, previously sterilized, with 
 yeast that had remained ten days at 40 C., the fermentation 
 having stopped. This yeast became prolific. 
 
 This experiment has been repeated often, and has always 
 given concordant results. 
 
 Our laboratory experiments confirm the second hypothesis, 
 which is supported by H. Dessolier's practical observations 
 in Algeria. 
 
 From a filled and fermenting vat, six hogsheads of wine 
 were racked when the temperature reached 25 C., then 
 successively six others, each at temperatures of 30, 35, 40, 
 and 42 C., the rest of the vatful was refrigerated, andifresh 
 hogsheads taken from it when the temperatures were falling, 
 passing 35, 30, and 25 C. The following table shows the 
 number of days required to completely transform the sugar 
 in each of these series : 
 
 Time required 
 
 Hogsheads. for complete 
 
 fermentation. 
 
 25 C ... ... ... ... 10 days 
 
 30 C ... ... ... ... 10 
 
 35 C ... ... ... ... 10 
 
 40 C ... ... ... 20 
 
 42 C more than ... ... 225 
 
 35 C ... ... -... ... 80 
 
 30 C ... 50 
 
 25 C 36 
 
 The maximum temperature reached only lasted a few 
 
 hours ; its influence, however, was sufficient to more than 
 
 treble the normal duration of fermentation. 
 
 Our results are still more definite, but we prolonged the 
 
 action of the temperature from eight to ten days, and thus 
 
 observed fermentation not completed after four months, in 
 
 the flask, at 40 C. brought down to 25 C. 
 
96 WIXE-MAKIXG IN HOT CLIMATES. 
 
 To verify the toxicity towards the yeast, of a liquid fer- 
 mented at 40 C., we tried it by adding a certain proportion 
 of fresh must, and sowing the mixture with active yeast. 
 
 With this object, eight volumes of wine at 25 C. and eight 
 volumes of wine at 40 C. were respectively mixed with two 
 volumes of fresh must. The quantity of sugar and alcohol 
 was rendered uniform in the two mixtures by additions of 
 alcohol and pure glucose. They were both sown with yeast 
 from the same culture, and both kept at a temperature of 
 28 C. 
 
 Regular weighings showed that the course of fermentation 
 was much more satisfactory in the flask containing the initial 
 wine at 25 G. than in that at 40 C. The loss of sugar was 
 twice as great in the first mixture, and was complete in nine 
 days, while in the mixture of the wine at 4U C., the fer- 
 mentation proceeded slowly, and a month after the start 
 the liquid still contained 16 grammes of sugar per litre. 
 
 Our experiments show, therefore, that a liquid previously 
 sterilized, and sown with pure yeast, may become unferment- 
 able under the sole action of a high and prolonged tempera- 
 ture. We must put aside the hypothesis of the toxicity 
 brought about by secondary fermentation, and only attribute 
 it to the action of the products eliminated by the yeast. We 
 do not deny the intervention of parasitic fermentation in 
 that sense. We simply desire to point out that the same 
 phenomena take place without it. 
 
 We intend to try and show that it is, without doubt, due 
 to the presence of albuminoid matters eliminated by the 
 yeasts. 
 
 The yeast eliminates volatile acids, mainly acetic and 
 propionic acids, but these exist in any fermentation, even 
 normal, and do not seem to have any action on the work of 
 the yeast, provided that they do not exceed a limit above 
 that normally given by the yeast. 
 
 Kayser has observed that the temperature of fermentation 
 has no influence on the quantity of volatile acids produced. 
 
 Volatile Acids calculated as Acetic Acid. 
 25 C. 35 C. 
 
 Yeast 2 ... ... 0-979 ... 0-780 
 
 8 ... ... M12 ... 1-504 
 
 9 0-862 0-828 
 
VINDICATION. 97 
 
 U. Gayon has recently pointed out* that whenever the 
 proportion of volatile acids increased, that phenomenon 
 coincided with the presence of micro-organisms other than 
 yeasts, which is in accord with the observations of Kayser. 
 
 As regards the production of higher alcohols and the 
 alkaloids which accompany them, it is very small, and these 
 substances have not a very energetic action on the yeasts. 
 The same may be said of substances such as leucine and 
 tyrosine, which are produced in such small quantities, that it 
 is necessary to operate on large volumes of liquid to detect 
 them. As also for pyridine and collidine, noticed by 
 Ordonneau, and proteine matters as yet undetermined which 
 we merely mention, and classify with the toxalbumens, 
 according to Roussy, who observed them in beer yeast. 
 
 To ascertain if these substances have an'analogy with those 
 observed by Roussy, we injected rabbits with liquids obtained 
 by macerating wine yeast previously washed for eight days 
 in distilled water at 25 and 40 C. We noticed rises of 
 temperature, in the animals which were given a few centi- 
 metres of the solution from the maceration at 40 C. after 
 filtration through a Chamberland candle. 
 
 The infusion at 25 C. does not give any apparent results, 
 but the injection of an equal volume of a yeast culture, that 
 had not been submitted to an abnormal temperature, also 
 produced hyperthermy. As the filtrate from the maceration 
 at 25 C. does not produce any effect, we may infer that the 
 active substances liable to be developed by the yeast are 
 elaborated in the organs of the animal, the temperature of 
 which is too high for the yeast. 
 
 It is therefore to these albumenoid substances, which we 
 consider analogous to those of Roussy, that we attribute the 
 sterility acquired by must, when left for a few days at a too 
 elevated temperature. 
 
 This sterility, however, is not permanent. According to 
 our experiments we cannot say that fresh yeast will not 
 develop at all in the liquid. It works there, but very slowly 
 at the commencement, and, what is very remarkable, more 
 actively later on, although the contrary would have been 
 expected, the activity of the yeast diminishing as the 
 alcoholic strength increases. If such a result takes place, 
 
 * U. Gayon. Sur les ucides contenus dans des vins. Revue de Viticulture, 
 April 24, 1889. 
 
 10649. G 
 
93 WINE-MAKING IN HOT CLIMATES. 
 
 it is due, no doubt, as Schutzenberger observed, to diastases, 
 amongst which are classified the toxalbumens, the diastase 
 being submitted to a progressive alteration, the effect of 
 which is the diminution, and even the complete loss, of the 
 specific power of the yeasts. 
 
 CONCLUSIONS. 
 
 First. For indigenous yeasts (South of France) the most 
 suitable temperature for fermentation is 30 C. (86 F.). We 
 think winemakers will with advantage keep their vats about 
 that temperature. 
 
 Second. The rise of temperature above 35 C. causes a 
 noticeable diminution in the final alcoholic strength. 
 
 Third. The qualities of a* wine, its organoleptic, and 
 perhaps pecuniary value, are in inverse proportion to the 
 temperature at which it fermented. 
 
 Fourth. The difficulty noticed in completely fermenting 
 a wine remaining sweet on account of excessive temperature, 
 is due to the liquid containing substances eliminated by the 
 yeast, and exerting a toxic action on it. 
 
 Fifth. Fermentations at high temperature give wines 
 richer in albuminoids, than those fermented at normal tem- 
 peratures. 
 
 Sixth. In our experiments, the greater amount of nitrogen 
 yielded cannot be attributed to parasitic ferments, for we 
 experimented with sterilized musts. 
 
 INFLUENCE OF THE TEMPERATURE OF 
 FERMENTATION ON THE YIELD IN ALCOHOL. 
 
 A fact which has attracted the attention of a few oanolo- 
 gists for some time, and which we have often observed, is the 
 enormous disproportion between the alcoholic strength and 
 the initial sugar contents of Algerian wines. The musts are 
 very rich in sugar, but the wines from them relatively 
 deficient in alcohol. This is so frequent that an incorrect 
 opinion is held by many Algerian vignerons. They consider 
 the mustimetre as an inaccurate instrument, always giving 
 exaggerated results. In many cases the differences are 
 even much greater than they think. 
 
 The observations with the mustimetre are generally made 
 without taking the temperature into account, and without 
 making any correction, and as in Algeria the temperature is 
 
VINDICATION. 90 
 
 always above 15 C., this faulty method of observation always 
 gives results below the normal. On the other hand, it is the 
 rule in Algeria to put into the fermenting vat grapes dried by 
 the hot winds blowing from the desert (the Great Sahara). 
 These grapes are rich in sugar, and increase the percentage 
 of sugar in the vintage without its being shown by the musti- 
 metre, as the sugar only dissolves slowly from the mass. 
 
 It is inadmissible that an instrument giving accurate in- 
 dications in France should give inaccurate indications in 
 Algeria. We must therefore acknowledge a loss, and we 
 have ascertained that the loss is considerable. We tried to 
 measure it in fermentations resulting from leaving the must 
 to itself after crushing, as is generally done in Algeria. 
 
 After having, as far as possible, rendered the must homo- 
 geneous in a vat of 250 hectolitres (5,500 gallons), samples 
 were drawn at different depths, and carefully tried with the 
 mustimetre, applying corrections for temperature. The in- 
 dications obtained from the samples were concordant. They 
 were also checked by determination of the sugar witli 
 Fehling's solution. The differences found were inconsider- 
 able. The must tried contained 243 grammes of sugar per 
 litre. According to Pasteur's experiments, inverted sugar 
 (identical with grape sugar) gives after fermentation 48*5 
 per cent, of its weight in alcohol ; in practice, however, this 
 yield is not reached. A yield of 47 per cent, may be con- 
 sidered as normal, corresponding to 1 per cent, of alcohol in 
 volume for 17 grammes of sugar transformed. The above- 
 mentioned must should therefore have furnished 
 
 243 
 
 pr = 14*3 per cent, alcohol. 
 
 Here are, in its main lines, the course of the fermen- 
 tation : 
 
 It started eight hours after filling the vat, which was 
 filled on the 3rd of September. During the whole day 
 on the 4th and first half of the 5th September the fermen- 
 tation remained very active. On the 5th of September, at 
 two p.m., there were only 83 grammes of sugar left 
 untransforined, but the fermentation was visibly slackening ; 
 the temperature taken at that moment in the vat was 
 At 50 centimetres below the head, 38 C. 
 
 1 metre 40. 
 
 the bottom of the vat 39'5. 
 
 G 2 
 
100 WINE-MAKING IN HOT CLIMATES. 
 
 On the same day, at six p.m., the maximum temperature 
 was 41*5 C., and the fermentation seemed to have 
 stopped, a determination of the sugar gave 78 grammes. 
 Twenty hours after the sugar strength had not varied, the 
 fermentation had stuck. 
 
 Racking was advised and took place the day after. The 
 wine tested after racking, contained 7*9 per cent, in volume 
 of alcohol, and 78 grammes per litre of untransformed 
 sugar. A few days afterwards the fermentation started 
 again, and continued at a low temperature (25 to 28 (.V) 
 outside, in casks of 550 to 600 litres (130 gallons). The 
 wine, when completely finished, showed 12*5 pet cent, alcohol, 
 and only traces of sugar.* 
 
 There has been, therefore, 14-3-12-5 1-8 per cent, of 
 alcohol less than the amount calculated. The yield in this 
 case has only been 87*3 per cent, of the normal, that is to 
 say, a net loss of 12-7 per cent. 
 
 This observation is not exceptional, it has been given with 
 details, because it was followed up with concordant results, 
 but we consider it as expressing the minimum loss that takes 
 place, as the fermentations last year in Algiers took place 
 under most favorable circumstances. 
 
 With regard to the vat studied, the temperature of the 
 grapes was not excessive, 22 C. The hot winds (Sirocco), it 
 is true, had blown during the night of the 1st and 2nd Sep- 
 tember, but the temperature had fallen on the evening of the 
 2nd, and remained relatively low during the remaining 
 period of fermentation. 
 
 There are, therefore, in this particular, case, favorable cir- 
 cumstances, tending to render it comparable with our fer- 
 mentations in the South of France. What can we expect, 
 then, when fermentation takes place under less favorable 
 conditions, such as those, for instance, the result of which we 
 have seen at Relizane, and which took place at temperatures 
 varying from 40 to 44 C. in the shade ? 
 
 From information gathered from several vine-growers, the 
 difference between the indications of the mustimetre and the 
 final alcoholic strength reached in some cases the extreme 
 figure of 3. 
 
 * We must draw attention to the fact that the sugar remaining after the 
 principal fermentation, was ultimately transformed, furnishing the normal 
 yield of alcohol. 
 
VINDICATION. 101 
 
 We can only see one cause, for these small yields, having 
 a direct action of a physical nature, and, perhaps, also 
 of a physiological order.' This cause is the excessive 
 elevation of temperature. This we may easily ascertain, 
 and we have done so ; the presence of notable quantities 
 of alcohol in the gases evolved during fermentation when 
 the temperature exceeds 36 C. being readily detected. 
 The alcohol may also be carried away mechanically at 
 lower temperatures, but in much smaller amount, and to 
 measure it, we need to use more effective means than 
 those employed above. It is, probably, to the alcohol 
 carried away, that the difference between the theoretical 
 yield obtained in the laboratory (48 '5 per cent . of the weight 
 of sugar), and that which we may call normal (47 per cent, 
 which results from wine-making practice in France), is due. 
 
 There is therefore always a loss which seems inevitable, 
 but we must try not to increase it. 
 
 To estimate the alcohol in the gases from the fermentation 
 we used Miintz's accurate process, which consists in trans- 
 forming the alcohol into iodoform, by means of iodine and 
 carbonate of soda, at moderate temperatures. If we plunge 
 into the gases escaping a cold body, such as the carefully 
 cleaned outside of a cold bottle, it will become immediately 
 covered with a condensed film, in which alcohol exists in 
 considerable proportion. It suffices, in order to detect it, to 
 wipe it with a brush into a test tube, and to apply to the 
 liquid thus obtained Miintz's test. One generally perceives 
 the odour of iodoform. If the test is made when the tem- 
 perature of the vat is approaching 40 C., not only does the 
 odour appear stronger, but the liquid contains numerous 
 crystals, which, when shaken, appear to the eye to have a 
 silky appearance, and deposit in a mass varying in size as 
 the experiment is continued longer, and as the surface of 
 condensation is colder, or as the temperature of the vat is 
 high. 
 
 If we rack into a recipient some of the wine while at a 
 high temperature, the presence of alcohol is still more 
 accentuated, the odour being easily noticed. 
 
 In the experiments we were able to make, the surface of 
 condensation was about 4 or 5 C. above zero, as there was 
 alcohol condensed at that temperature, the , tension of the 
 alcoholic vapours in the gaseous mass must at least have 
 been equal to that corresponding to the temperature of the 
 
102 WINE-MAKING IN HOT CLIMATES. 
 
 condensing surface. The tension at 4 or 5 C. is represented 
 by about 18mm. of mercury, and we may easily conceive 
 that the loss of alcohol through being mechanically carried 
 away may be considerable, if we consider the enormous 
 volume of gas resulting from the phenomena of fermentation. 
 
 The quantitative determination of the loss under given 
 circumstances could only be experimentally determined, but 
 we feel sure that it is very considerable in Algeria, far more 
 so than is generally thought to be the case, and this is ex- 
 plained by the comparison of the tension of vapour of al- 
 cohol at the average temperatures of 30 C. in France and 
 40 C. in Algeria. 
 
 The tensions in mm. of mercury are 78' at 30 C. and 1 34* 
 at 40 C. 
 
 In what has been said so far, we mean by yield the 
 amount* of alcohol obtained, as compared with the sugar 
 transformed, and not in relation to the total amount of 
 sugar. For it would be a very different thing if we meant by 
 yield the alcohol obtained, without taking into account the 
 quantity of untransformed sugar. Another important action 
 of the temperature is to completely arrest the fermentation 
 at 40 C. ; if the liquid remains in that state, the natural de- 
 crease of temperature is not complete or rapid enough to 
 allow the yeast to recover its activity, and a part of the 
 sugar remains untransformed, which contributes to the 
 diminution of the yield in alcohol, and constitutes a cause of 
 future alterations. 
 
 If the temperature of the fermenting must is carefully 
 maintained below 32 C., in Algeria or anywhere else, the 
 resulting wine shows a normal yield of 47 per cent, of 
 alcohol per 100 of sugar transformed in weight, and the 
 whole of the sugar is transformed, even in the case of wine 
 of high alcoholic strength. We have been able to verify 
 this fact in the most positive manner, in a cellar, where two 
 fermentations only differed in their temperatures. 
 
 By applying to the fermenting must a slight refrigeration, 
 the losses are simply diminished, and we obtain a medium 
 yield. 
 
 If we represent the normal yield as 100, the yield of a vat 
 allowed to rise to 40 C. would be 87'3, that of the same vat 
 refrigerated would be 92, and that of the vat not allowed to 
 exceed 32 C. would be 100. 
 
VILIFICATION. 103 
 
 To sum up, ice consider that any elevation of tempera- 
 ture above 30 C. is an important cause in the diminution 
 of the alcoholic strength, and that the installation of re- 
 frigerating plant is necessary in every cellar exposed to 
 high temperatures. 
 
 Whatever expense is incurred by this improvement of the 
 process of vinijication will be amply repaid by the superior 
 value of the wines made by this method. They will be more 
 alcoholic, brighter, and, above all, possess better keeping 
 qualities than wines made in the ordinary way. 
 
 INFLUENCE OF THE TEMPERATURE OF VINOUS FERMENTA- 
 TION ON THE QUALITIES OF WINE. 
 
 As has been already said, the excessive temperature in- 
 fluences the yield of alcohol in two ways one physical the 
 other physiological. It is necessary to study the physio- 
 logical or indirect influence, for it results, not only in the 
 diminution of the alcoholic yield, but also constitutes the 
 principal cause of the poor quality of wines. 
 
 The activity of the wine ferment is considerably slackened 
 down when the temperature gets over a certain limit. The 
 curve described above allows us to see easily the slackening 
 of the fermentation, and the stoppage of its action. The 
 functions of the alcoholic ferment are destroyed, and in 
 many cases noxious ferments take its place, consuming the 
 sugar without producing alcohol, and introducing into the 
 wine new products altering its organoleptic properties. 
 
 This is not the only alteration. The alcoholic ferment 
 is not dead, for sown again in new must, and under favor- 
 able conditions, it will regain its activity ; but it is mor- 
 bid, and shows morphological differences, detectable by the 
 microscope, so definitely, that by simply observing it under 
 the instrument we are able to say if the temperature has 
 risen above 36 C. 
 
 We are inclined to think that the products of elimination 
 of a living organism sufficiently diseased, for its shape to be 
 altered, must differ from those eliminated normally. In 
 confirmation of this opinion, we have, by means of the 
 microscope, classified many wines made from the same 
 cepages under similar conditions, containing foreign bacteria 
 in notable numbers. At M. Debonno's well-known vine- 
 yard at Boufarick we were able to control this classification 
 with the microscope, assisted by two expert wine-tasters 
 MM. Aury and Vielle, of Algiers. 
 
104 WINE-MAKING IN HOT CLIMATES. 
 
 Among the wines tasted were four samples of white wine, 
 racked a few days previously, and still cloudy but quite 
 dry, that is to say, containing- only traces of sugar. The 
 absence of sugar was a sign that the temperature had not 
 risen enough to completely paralyze the ferment. The 
 microscopical examination disclosed that all the fermenta- 
 tions had not taken place at equal temperatures, as some of 
 the yeasts appeared to have suffered. Methodical refrigera- 
 tion is used in M. Debonno's cellar, but the instalment is 
 insufficient to refrigerate effectively the huge quantities of 
 vintage manipulated each day. By microscopical observa- 
 tion the wines numbered 1, 2, 3, and 4 were classified 
 according to their value, 1, 3, 4, 2. MM. Aury and Vielle, 
 simply by tasting, classified them in exactly the same way. 
 This test has been repeated frequently, and always with 
 success, and with wines completely turbid, in which condition 
 it was not possible to make any conjecture as to their future 
 quality. 
 
 The same observations were carried out on two white 
 wines made from the Cinsaut cepage, the grapes having 
 been gathered the same day, and fermented, some in a 
 metallic vat (Toutee system), and some in a wooden vat of 
 125 hectolitres capacity; the temperature did not exceed 
 29 in the metallic vat and was 38*5 C. in the wooden one. 
 The fermentations started on the 15th September, and they 
 were both almost finished on the 18th. 
 
 Microscopical observation showed that the wine made 
 in the metallic vat contained only vigorous turgid yeasts, 
 highly refractive; in the wine from the wooden vat, the yeasts 
 were unhealthy, shrivelled, and wrinkled ; they did not in 
 either case contain bacteria, but to the taste the wine made 
 in the metallic vat was much superior. 
 
 These facts certainly support the opinion we have already 
 given the wine yeast eliminates at high temperatures pro- 
 ducts injurious to the wine. The elimination of abnormal 
 products, by the ferment in a visibly morbid state, is one of 
 the principal reasons of the inferior yield of alcohol, in wine 
 fermented at a high temperature. But we are far from 
 denying the analogous action of foreign injurious bacteria 
 often developing at a temperature detrimental to the alco- 
 holic yeast itself. 
 
 These foreign fermentations happen very frequently. Des- 
 soliers, in a very thorough study on " Vinification in Hot 
 Climates," published in the Algerie Agricole, mentions this, 
 
VINDICATION. 105 
 
 but we maintain that the predominant effect is due to the 
 wine yeast itself. In the wines just mentioned there were no 
 foreign organisms in appreciable quantity, the alteration of 
 the organoleptic qualities cannot therefore be attributed to 
 the secondary fermentation, but to defective vinous fermenta- 
 tion. 
 
 When the fermentation rises to a temperature high enough 
 to prevent the transformation of the sugar, the damage is 
 still more serious, especially if it remains for some time at 
 this temperature. 
 
 We think, without being able to positively assert it, that 
 the yeast accumulates morbid products in the ust in suffi- 
 cient quantity to render the must sterile. It is from this 
 sterility that the sweetish acid taste of incompletely fermented 
 wine arises. The must is then invaded with a host of 
 organisms, amongst which may be found germs of all the wine 
 diseases, which develop with extreme rapidity, living no 
 doubt at the expense of the sugar, and converting the wine 
 into an undrinkable liquid, only fit for the still, which even 
 then only produces spirit of inferior quality. 
 
 We have observed a great number of these wines in the 
 Chelif plain, when travelling from Oran to Algiers, where 
 the conditions for the vintage were not found this year 
 to be as favorable as in other viticultural centres in Algeria. 
 Several days after the first racking, and even on the marc, 
 these wines contained a great quantity of sugar, and only a 
 few wrinkled yeast cells could be detected under the micro- 
 scope. On the other hand, they were real breeding grounds 
 for a great variety of bacteria. We only found exceptions 
 to this fact in cellars where wine was fermented in small 
 quantities, and therefore could not reach a high temperature. 
 
 The excessive temperature acts in a third manner in 
 diminishing the value of wine. White wines, fermented 
 without contact with the marc, are not submitted to this 
 action in the same way, or to the same extent, as red wines 
 fermented on the marc. Wine tasters are unanimous in 
 recognising the relative inferiority of red wines which have 
 fermented at a high temperature. They find that they taste 
 of the -marc, and that they terroitent, to use the expression 
 employed locally. We are, therefore, led to suppose that the 
 products dissolved by the wine from the marc, at least at 
 different temperatiires, are not the same quantitatively. 
 Chemical analysis does not reveal positive differences. We 
 
106 WINE-MAKING IN HOT CLIMATES. 
 
 can only note as a constant fact that the reduced dry extract 
 of wine, made at a high temperature, is in excess of normal 
 wines made from the same cepage. In fact, if we examine 
 the marcs from fermentations made at 30 and 40 C., the 
 tissues of the latter are found to be much more disorganized. 
 To conclude, we consider that the elevation of the temperature 
 above a certain limit (32 C.) diminishes the quality of the 
 resulting wines. It is therefore necessary, in order to improve 
 our wines, to check elevation of temperature by the use of 
 refrigerating appliances. 
 
 INFLUENCE OF THE TEMPERATURE OF FERMENTATION ON 
 THE KEEPING QUALITIES OF WL\E. 
 
 After what has been said about the influence of the tem- 
 perature of fermentation on the quality of wine, it is almost 
 superfluous to speak of its action on the keeping quality of 
 wine, for the two terms quality and keeping quality are 
 almost synonymous when applied to wines having the same 
 origin. However, we consider it advisable to dwell a little 
 longer on this subject, to show the detrimental effects of high 
 temperatures. 
 
 Wine is a liquid composed of different parts, which can be 
 divided into two groups. The first includes alterable sub- 
 stances such as albumenoid matters, sugar, acid-tartrate of 
 potash, &c.; the other comprises antiseptic matters pro- 
 tecting the first group against possible alterations. These 
 are alcohol, glycerine, tannin, and various acids. In the 
 manufacture of wine, therefore, we should try and diminish 
 the quantity of alterable matters, and increase the quantity 
 of natural antiseptic substances. 
 
 In fermentations made at 30 C. the quantities of these 
 various substances seem to exist in proper proportion : 
 experience has proved that wines obtained at that tem- 
 perature, even if only submitted to summary care subse- 
 quently, are able to keep well. 
 
 Experience has also proved that fermentations made above 
 that temperature, which we will call the optima for the yeast, 
 yield wines much more liable to alteration, this liability to 
 change varying in proportion as the temperature rises or 
 falls from that optima, and being greater for high tempera- 
 tures. It is to this that Algerian wines owe their reputation 
 for bad keeping qualities. An opportunity occurred in 1892 
 of noticing a disease in Algeria which seemed peculiar to 
 
VINDICATION. 107 
 
 Algerian wines, but which has since been found more general; 
 this is known as mannitic fermentation. We were able to 
 show in 1892,* from experiments made in the laboratory, 
 and in Algeria during the vintage, that the disease was due 
 to bacteria, and that it was simply the result of the extreme 
 temperature, which had killed the yeast without killing the 
 bacteria, which always exist in great quantities even in 
 healthy vintages. Gayon and Dubourg have recently isolated 
 the mannitic ferment, and confirmed these observations, and 
 proved, as a result of their study, that the mannitic fermenta- 
 tion can only take place after an incomplete alcoholic 
 fermentation. This disease is very frequent in wines made 
 at a high temperature, for there undecomposed sugar is 
 always left, but if the temperature of the fermenting wine is 
 brought down it will not occur. There will be no sugar 
 left, and consequently no fermentation is possible. 
 
 Other wine diseases, it is true, may develop even in com- 
 pletely fermented wines, but their development is infinitely 
 more frequent if the fermentation has been defective. 
 
 High temperature is therefore injurious to the keeping 
 quality of wine. It leaves in the wine a large proportion 
 of alterable substances, and is the cause of the diminution 
 in the alcohol as also of the glycerine, both of ivhich are 
 excellent preservative substances. 
 
 REFRIGERATION OF MUSTS DURING FERMENTATION. 
 The refrigeration of musts during fermentation has not 
 yet obtained the sanction of being an old practice, but trials 
 made since 1892 in our Africanf colony, and considerably 
 increasing every year in various parts of Algeria, have shown 
 decisively that the solution of the problem of wine making in 
 hot countries depends entirely on this operation. 
 
 * Journ. de Pharm. et de C/iimie, 1893. 
 
 + In connexion with the recent extensive application of the system of 
 refrigerating musts during fermentation, in the South of France and Algeria, 
 it is interesting to refer to an Australian work by Dr. A. C. Kelly, The Vine 
 
 T- ' -fXT- r*-* ft- _ __1_1" 1 1 "_ -1 Ot?1 TVT-11 *^J O.-.K,, ,- TM tl.i.- 
 
 sive and convincing, but were greatly in advance of the times, for, although 
 written some 40 years since for the immediate benefit of Australian wine- 
 makers, it is well-known that they are even now only tardily availing them- 
 selves of the advantages to be derived from fermenting their musts under proper 
 conditions. 
 
 The paragraphs of Dr. Kelly's work dealing with the importance of the 
 temperature during fermentation are, on account of their present interest, 
 reproduced completely in the Appendix to this work. (Trans.) 
 
108 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 In the South of France, the difficulties met with in Algeria 
 exist to a lesser extent, and if refrigeration there is not 
 indispensable it is nevertheless so useful that results obtained 
 in different vineyards during the last two or three years 
 enable us to predict the general adoption of this system at 
 an early date. 
 
 How should the fermentation be conducted ? 
 
 Two systems have been proposed : the first consists in 
 cooling the must in the vat, the second in cooling it 
 outside. 
 
 The first system may be applied in two ways : one as used 
 at Jaffa, by Ermens, consists in a long pipe (coiled spirally) 
 fixed in the vat itself, and through which cold water circulates 
 during the fermentation. (Fig. 18.) The application of 
 
 B 
 
 Scale. 
 
 Fig-. 18 Ermens arrangement for refrigerating inside the Vat. 
 
VILIFICATION. 109 
 
 this system is so very expensive, and according to the 
 inventor necessitates the use of such large quantities of cool 
 water to give good results, that it cannot be advocated. 
 
 The second method of refrigeration of the must inside the 
 vat is more tempting, because it is more simple. It con- 
 sists in .facilitating the exterior radiation of the heat of the 
 must, by the use of vats made of material of great con- 
 ductivity. These are the metallic vats of Toute"e. 
 
 We had an opportunity of watching two fermentations, 
 one in a wooden vat of 125 hectolitres capacity, the other 
 in a metallic vat of the same size. The maximum tem- 
 perature in the wooden vat was reached at 38-5, and in 
 the metallic vat at 29, a difference in favour of the 
 metallic vat of 9-5 C. 
 
 This decrease of temperature was ample, but we must 
 take into account that it was white grape must, in which 
 the homogeneity of the temperature is greater than in 
 red must. In the latter the head, or mass of marc, is a 
 danger zone, and ought to be refrigerated first. It forms 
 a compact felted block, which does not partake much 
 of the diminution of the temperature produced by 
 the conductivity of the walls of the vat. It would 
 be necessary in order to obtain in the fermentation of 
 red musts a result equivalent to those of white must fermen- 
 tations, to establish continuous circulation of the liquid 
 pumped from the bottom of the vat to the top of the head. 
 This manipulation already used to a great extent with any 
 system, of fermentation would not be very complicated, the 
 only question to be considered is the monetary outlay, the 
 adoption of the Touted system meaning the integral renewal 
 of all the vats. 
 
 Refrigeration of the must by circulation outside the vat may 
 be effected in two different ways, sometimes it is spread in 
 contact with the air over a great surface. This leads to evapo- 
 ration and therefore refrigeration, increased if necessary by 
 a strong air blast, or else the must circulates in a closed 
 space refrigerated outside by a current of cool water, by 
 damp cloths, or sometimes by the air itself, for it is only a 
 question of surface. This latter system, we consider, should 
 be preferred. 
 
 The refrigeration of musts in contact with the air creates 
 energetic oxidation of the wine. 
 
110 WINE-MAKING IN HOT CLIMATES. 
 
 The oxidation is an advantage, if done before the start 
 of the fermentation, but it is not so in the case of wine 
 partly or completely fermented. When the fermentation is 
 started the aeration may be useful, but it should be sparing if 
 we desire to protect the wine against the disadvantages 
 which it leads to. 
 
 Fermenting wine, if kept too long in contact with the air, 
 becomes flat and insipid. 
 
 It is therefore better to adopt the system of refrigeration 
 without contact with the air, and aerate afterwards if judged 
 necessary. 
 
 It is by no means difficult to obtain simple and very 
 effective cooling apparatus. It is not necessary, as in the 
 case of a brewery, to reduce the temperature very low, but 
 simply to keep the fermentation about 30 C. 
 
 Water and air are the only two refrigerators that can 
 be used economically. 
 
 The air at vintage time in the South of France is 
 generally below 30 C., and is always at the disposal of the 
 vine-grower in unlimited quantity, and might be used. 
 
 Water, unfortunately existing in too limited supply, is 
 much more convenient, as it is generally at a lower tem- 
 perature than the air, and even if it were at the same tem- 
 perature, it produces an equal cooling effect from a smaller 
 surface of contact. 
 
 Water therefore should always be the refrigerating means, 
 whenever sufficiently plentiful. 
 
 A simple tube, more or less long, wetted outside by a current 
 of water, constitutes the machine, and is connected with 
 the bottom and top of the vat. Tinned copper tubes are 
 all that is required to make a wine refrigerator when water 
 is at disposal. The pipes may be joined by pieces of rubber 
 hose and placed in a suitable trough, in one length or in 
 a tank zigzaging, divided by partitions to regulate the 
 circulation of the water. This form presents the advantage 
 of being easily pulled to pieces and used afterwards as 
 ordinary conducting pipes. 
 
 The decrease of the temperature of the wine induces a con- 
 siderable deposit of tartar, which necessitates the use of 
 tubes of large diameter, easily dismantled for cleaning. 
 
 An apparatus of this kind may be fixed without much 
 expense in a cellar having water available, and can if neces- 
 sary, even be placed outside the cellar. 
 
VINDICATION. Ill 
 
 If only a limited supply of water is available this device 
 can still be adapted, if the water is collected to be used 
 over again when its temperature has decreased, OF, prefer- 
 ably, another system may be used utilizing more completely 
 the cooling power of the water, with or without the inter- 
 vention of air. 
 
 The cooling effect of the air may take place directly, simply 
 by exchange of temperature, the surrounding air being 
 generally cooler than the wine, or indirectly by evaporation 
 of part of the water used for refrigerating. This physical 
 phenomenon being always accompanied by a decrease of 
 temperature. In the latter case it is not indispensable for 
 the air to be colder than the wine. 
 
 The metallic vats of Toutee only utilize, when bare, the 
 refrigerating effect of the air, but if covered with cloth kept 
 wet they utilize the refrigerating effect of the evaporation 
 also. It goes without saying that in this case the cooling 
 effect is greater. 
 
 We have seen by the figures quoted relative to fermenta- 
 tion in metallic vats, that these are quite sufficiently effective 
 for white and red wines, if in the case of the latter the must 
 is pumped over the head. 
 
 The adoption of the Tout6e system is therefore indicated 
 for a cellar with limited water supply, but it would be too 
 expensive to establish in a cellar already furnished with 
 vats. 
 
 When the water supply is limited, we must try to use the 
 same water again, or develop surfaces large enough to act 
 with air alone, or adopt a mixed system in which air and 
 water act together, as in the Toutee vat covered with cloth. 
 
 Whatever be the ingenuity of apparatus utilizing water 
 alone, its consumption will always be large, more than half 
 the volume of wine cooled, but if the water supply is suffi- 
 cient for one day's operation, the night cooling will be ample. 
 With arrangements easily devised we may bring back the 
 water to a suitable temperature, ready to be used again the 
 next day. 
 
 But there are cases where the cooling of the water must 
 be done at the same time as it is employed. 
 
 Dessoliers proposed to rapidly reduce the temperature of 
 the heated water with a kind of refrigerator, submitting it 
 to a great surface for evaporation, aided with a strong blast, 
 and devised for that purpose an apparatus called cheminee 
 
112 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 climagene (Fig. 19), which consists of a chimney more or 
 less high, according to the quantity of water to he treated, in 
 
 Fig. 19.--Climagene chimney of Dessoliers A, Distributing tank for the hot 
 water; B, cellular bricks ; C, receiving tank for the cooled water ; d, pump; b, ven- 
 tilating fan ; a, e, level indicator. 
 
 the centre of which cellular 
 bricks are piled up to the 
 top, overlapping each other. 
 The water poured on the top 
 descends to the bottom, 
 spreading completely over 
 the surfaces of the bricks 
 (Fig. ^0). A strong venti- 
 lating fan sends an air blast 
 from bottom to top, creating 
 active 1 evaporation, with 
 consequent cooling of the 
 water. 
 
 Fig. 20. Olirnagene Chimney of Dessoliers 
 Arangement of the cellular bricks. 
 
VILIFICATION. 113 
 
 With the cheminee climag<me, the results are excellent, but 
 the same result can be reached without going to the expense 
 of such a building. 
 
 There are different materials easily procurable every- 
 where, such as coke, already employed for similar purposes 
 by other industries, which present a larger surface than 
 cellular bricks. We feel certain that a cylinder made of 
 double hogsheads, with the bottoms knocked out, and filled 
 with coke, would afford a better solution of the problem 
 than Dessolier's chimney. 
 
 It is rational to utilize evaporation, as it is so active in 
 hot climates, but apparatus based on that principle only, 
 that is to say, in which the outside surface is just maintained 
 moist, cannot have a constant refrigerating action. 
 
 The refrigeration in this case depends on the hygrornetric 
 state of the air, and on the rapidity of the air current. 
 
 Theoretically, the cooling produced by evaporation is pro- 
 portional to the difference existing between the maximum 
 tension of water vapour at the temperature at which the 
 work is being done, and the tension existing in the air at the 
 same moment. 
 
 If we suppose the air to be completely dry the refrigerating 
 power seems unlimited, for if the air is constantly renewed 
 it will continuously vapourize the water, and therefore reduce 
 the temperature. In reality, equilibrium takes place at the 
 moment that the heat lost by the water by radiation and 
 evaporation becomes exactly equal to that received from the 
 surrounding air. 
 
 These states of equilibrium were experimentally deter- 
 mined by Gay-Lussac, who determined them for temperatures 
 between and 25 C. by the figures indicating the maximum 
 decrease of temperature that can be obtained. The figures 
 interesting to us are those corresponding to the temperatures 
 of 15, 20, 25 0., and they are respectively 10-8, 12'7, 
 and 14-7. 
 
 These experiments were repeated by Regnault, and appeared 
 to him to be incomplete, as the influence of the rapidity of 
 the current of air on the decrease of temperature was not 
 studied. This decrease increases with the rate of movement 
 of the air current, when it is higher than 8 metres per 
 second, which corresponds to a strong wind, but is easily 
 obtainable with a ventilating fan. 
 
 10649. H 
 
114 WINE-MAKING IN HOT CLIMATES. 
 
 All the results apply to dry air, if the air is damp they 
 will be lower, although remaining in the same proportion, 
 and become nil if the air is saturated with moisture. 
 
 There are therefore in the utilization of evaporation two 
 factors, one of which can be modified the speed of the 
 current of air ; the other, which is not controllable, being 
 the hygrometric state of the atmosphere ; but the action of 
 the latter is so pronounced that it would be imprudent to 
 depend on a system based on evaporation alone, in certain 
 regions where the hygrometric state is very variable. 
 
 The effect with such a machine would, however, never be 
 nil, notwithstanding what has been said ; even if working 
 in a saturated atmosphere the effect will always be greater 
 than we could have expected from the exact measurement of 
 the quantity of water evaporated. 
 
 It seems at first sight that the decrease of temperature 
 obtained can only be constituted by the sum of the calories 
 given to the water, and that necessary to evaporate the 
 weight of water which disappears during the experiment. 
 If we represent by A the first of these numbers, by B 
 the second, and by C the number of calories lost by the 
 wine, it should be possible to write A + B C. In practice 
 this is not so. Not only is A + B less than C, but 
 experience proves that often A + B is only half of C. 
 
 The heat lost cannot be equal to the heat gained, we must, 
 therefore, conclude that there are undetermined elements in 
 the calculation, which intervene to a large extent, and which 
 cannot be measured directly. They are the exchanges with 
 the surrounding; air. These .are so much the greater as the 
 temperature of the wine varies from the surrounding air, 
 assuming that the surface of evaporation is of constant 
 conductivity. 
 
 We have experimented on a cooler constructed purposely 
 with a view of utilizing the evaporation effect only. It 
 gave insufficient results under rather good atmospheric con- 
 ditions. The surface of evaporation acted upon was rather 
 small, it is true. The apparatus consisted of six very flat 
 lenses made of tinned copper, mounted horizontally on a 
 vertical tube, and of a diameter of 40 centimetres. The 
 decrease of temperature observed in wine at 38 to 40 C. 
 was from 3'5 to 5*5 C., varying according to the strength of 
 the current of air, the surrounding temperature, the hygro- 
 metric state of the air, and the rate of flow of the wine, 
 
VINDICATION. 115 
 
 which was between twelve and fifteen hectolitres per hour. 
 Although not perfectly satisfactory, an improvement in the 
 yield of alcohol resulted, which reached 4'7 per cent, more 
 than that of the non-refrigerated wine (92 against 87*3, 100 
 being the normal yield). 
 
 No doubt larger decreases of temperature could be 
 obtained by using larger surfaces, but there will always be 
 an uncertainty of success in countries where the hygrometric 
 state varies, as it does in the South of France, during the 
 vintage time. 
 
 The problem of refrigerating musts is not very complex. 
 There are no insurmountable difficulties, for it is not 
 necessary to get a very low temperature as in the case of 
 beer ; but only to reduce to 27 or 28 C. a vatful which has 
 overreached 32 C. 
 
 It is advisable to go slowly and maintain an average 
 temperature in the vat rather than to cool suddenly, for we 
 imagine that a sudden large decrease of temperature can 
 only be injurious to an organized plant such as yeast. If, 
 on the second day after the start, the fermentation has not 
 exceeded 28 C. we can without fear let it go on naturally. 
 The temperature will not become excessive, for by that time 
 the reaction producing the heat is almost all over. 
 
 STUDY OF VARIOUS MUST REFRIGERATORS. 
 
 The expense of refrigeration of the vintage consists of the 
 sum representing the sinking fund of the machine 10 per 
 cent, of its value the labour necessary for pumping the 
 water, which varies with local conditions, and the labour for 
 pumping the wine. 
 
 The labour is, of course, proportional to the volume 
 treated. It can, therefore, be expressed by a fixed sum per 
 hectolitre. This is very small, but the sinking fund for the 
 machine is so much the greater as the volume of wine 
 treated is smaller. 
 
 Suppose, for instance, a cooler costing 1,500 francs 
 (62 10s.) applied to a vintage of 1,000 hectolitres (22,000 
 gallons) the operation will be over-estimated from the sinking 
 fund by 15 centimes per hectolitre, while if the instrument 
 is applied to a vintage of 10,000 hectolitres (220,000 gallons) 
 the over-estimation will diminish to 1J centimes per hecto- 
 litre. 
 
 H 2 
 
116 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 In no case, however, will the expense reach the increased 
 value acquired by the refrigerated wine. But it would 
 always be better in dealing with small vintages to buy 
 smaller machines, as these are less complicated and less 
 expensive. 
 
 The apparatus of Miintz and Eousseaux is an excellent 
 modification, for vinifieation, of a device used in other indus- 
 tries, and is actually adopted in many important cellars.* 
 
 It is composed 
 JL of two parallel 
 
 series of nineteen 
 tubes superposed. 
 Fig. 21. Each 
 tube is open at 
 both ends and 
 fixed to a vertical 
 plate. A water- 
 tight obturator is 
 fixed on each plate 
 in such a way as to 
 be easily detach- 
 able. Communi- 
 cation is estab- 
 lished between the 
 tubes in such a 
 manner that the 
 liquid introduced 
 at the bottom 
 passes succes- 
 sively through all 
 
 Fig. 21. -Miintz and Rousseaux Refrigerating Apparatus. the tubes before 
 
 reaching the top. 
 
 A tube joins the top of one series to the bottom of the other. 
 A trough with a row of small holes spreads water over the 
 tubes, which are covered with canvas, the water drips over 
 the tubes and falls to the bottom trough. 
 
 This apparatus successfully utilizes the cooling effect of 
 the water, as the wine is exposed to a large surface before 
 
 * An important work by Miintz and Rousseaux, Etudes sur la Vinification 
 et sur la Refrigeration des Mouts, appeared in 1896, and was translated and dis- 
 tributed in pamphlet form amongst Victorian vine-growers in the same year 
 by one of us.-(W.P.W.) 
 
VINDICATION. 
 
 11' 
 
 returning to the vat, Each tube measures 4 metres (13 feet) 
 in length and has a diameter of 40 millimetres (1J. inches). 
 
 It is an expensive machine, which does not seem to be 
 altogether suitable for small growers, but it is in its proper 
 place in large cellars. 
 
 We made some experiments on other coolers which 
 seem simpler in construction, and of more reasonable price, 
 for the use of small and medium cellars. It goes without 
 saying that we only considered machines capable of being 
 easily cleaned, owing to their shape, and the facility with 
 which they could be taken to pieces. 
 
 We tried three systems one constructed by P. Paul on 
 ideas we exchanged together ; one invented by Rouviere- 
 Huc, and described in the Proyres Agricole ; and the 
 third simply composed of concentric communicating vessels, 
 invented by P. Andrieu. 
 
 The machine designed by Paul and Roos is composed essen- 
 tially of two concentric tubes, 4 metres in length, of 2 or 3 
 centimetres in diameter, plunging into a trough of small 
 capacity. Each sheaf of concentric tubes forming an element 
 of the system, the number of the elements varying according 
 to requirements. Fig. 22. 
 
 Fig. 22. P. Paul's Refrigerating Apparatus. Forecarriage, B, exit of the cold wine. 
 
 The wine circulates in the annular space between the 
 inside surface of "the outer tube and the outside surface of 
 the inner tube. The water travels in an opposite direction 
 
118 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 to the wine, first of all passing in the inside tube, acting 
 through the inside surface of the annular space, then in the 
 trough continuing its action on the outside surface. 
 
 In a machine composed of several divisions the wine rises 
 from one division to another, while the water descends from 
 one trough to another to be emptied at the last one. 
 
 The interior tubes are fixed to the extremities of the 
 exterior tubes by screened discs, fixed in the same way as an 
 ordinary pipe coupling. Tightening the screws at one end 
 of the tubes makes the whole system watertight by com- 
 pression on rubber rings. The dismantling of the machine 
 for cleaning purposes is simple, and the cleansing is very 
 easily done, as the tubes are straight. 
 
 The annular spaces of the two divisions are joined together 
 with flexible rubber hose and fixed by means of a coupling. 
 
 Finally, with the view of utilizing ice, which can now be 
 obtained at very small cost, low enough to permit its use, 
 the system has a box attached to the top to contain the ice, 
 over which the heated water is spread and cooled before 
 being used. Fig. 23 and Fig. 24. 
 
 Fig. 23. P. Paul's Refrigerating Apparatus. - A, entrance of wine to be treated ; 
 C, annular space in which the wine circulates ; D, water supply ; E, entrance of cold 
 water ; F, exit of warm water. 
 
VILIFICATION. 
 
 119 
 
 Fig. 24. Paul's Refrigerating 1 Apparatus. Section view. 
 
 The first tests were made at the petroleum refinery, at 
 Balaruc-les-Bains, and we owe to the kindness of M. Durrand, 
 Director of this important establishment, the opportunity 
 given to make these tests under the most desirable 
 conditions. 
 
 The tanks used for the condensation of the petroleum con- 
 sumed daily 1,000 cubicmetres of water, which, entering 
 cold, flowed out at a temperature of about 50 C. If the 
 water is carefully collected at various distances descending 
 from the surface, we obtain all the temperatures com- 
 prised between the entering and exit temperatures of the 
 water. 
 
 The tanks are of considerable dimensions, and receive the 
 vapours from enormous boilers. It is possible therefore 
 when distillation is in full swing to remove 20 or 25 hecto- 
 litres of water per hour during many hours without the 
 temperature varying 0'5 C., if it is drawn from a constant 
 depth. 
 
 These are very favorable conditions for a test of this 
 kind. 
 
1'20 WINE-MAKING IN HOT CLIMATES. 
 
 The cooler we have just described gave, with water trials, 
 
 the following results : 
 
 EXPERIMENTS MADE ON THE 22xD AUGUST, 1S96. 
 
 1. Quantity of wine (represented by 
 
 warm water) ... ... 2O5 hectolitres per hour 
 
 Quantity of cold water... ... lo'O 
 
 Temperature of wine at entrance (warm water) 35'9 C. 
 Temperature of wine at exit 28 C. 
 
 Temperature of water at entrance ... ... 19 C. 
 
 Temperature of water at exit .. ... 27 C. 
 
 2. Quantity of wine (represented by 
 
 warm water) ... ... 20 hectolitres per hour 
 
 Quantity of cold water... ... 14*50 
 
 Temperature of wine at entrance (warm water) 31'7o C. 
 Temperature of wine at exit ,, ,, 26-3 C. 
 
 Temperature of water at entrance ... ... 19-0 C. 
 
 Temperature of water at exit ... ... 2-5-,'i C. 
 
 (Results obtained after two hours' work.) 
 
 A trial was made the following day, starting (as an 
 experiment) with a higher temperature for the wine 
 entering. 
 
 The quantity delivered was in one case 20-50 hectolitres 
 for the wine and 1 4-50 hectolitres for the water. 
 
 1. Temperature of wine at entrance (warm water) 35'G C. 
 Temperature of wine at exit ... ... 28-0 ('. 
 
 Temperature of water at entrance ... ... 18'2.C. 
 
 Temperature of water at exit ... ... 28'2 C. 
 
 2. Temperature of wine at entrance (warm water) 39-5 C. 
 Temperature of wine at exit ... .. 31'0 C. 
 
 Temperature of water at entrance ... ... 18'o C. 
 
 Temperature of water at exit ... ... 31-0 C. 
 
 (Results obtained after two hours' work.) 
 
 In all these trials the quantity of warm water used, 
 representing the wine, was measured with great exactitude. 
 The machine was fed from a tank the level of which was 
 constant. The syphon supplying the refrigerator yielded 
 less than the tank received. 
 
VILIFICATION. 121 
 
 It was, unfortunately, not possible to measure so exactly 
 the water used for refrigerating, as it was drawn from a tap 
 branching from a pipe feeding other taps at the same tirne> 
 so that although the tap was maintained at a constant 
 aperture, fluctuations in the delivery of water may have 
 occurred, small, no doubt, but sufficient however to pre- 
 vent us from trying to estimate the refrigerating action 
 attributable to the air. 
 
 The measurements for water given in the above tables 
 were made at the maximum, that is to say, when the pipe 
 only fed the tap used. 
 
 When tried in a cellar with the vintage fermenting in 
 wooden vats, this refrigerator gave similar results. We 
 must draw attention, however, to a special feature of this 
 machine. 
 
 On account of the thickness of the layer of wine circulating 
 in the annular space being very small there is great danger 
 of obstruction. 
 
 The refrigerator or cooler used had tubes, whose radius 
 differed only by one centimetre. Although the machine 
 worked well for a few hours we consider this difference is too 
 small and should be doubled. 
 
 It is necessary to introduce into the cooler must free from 
 solid suspended matters, such as skins, &c. 
 
 It should be used as follows : 
 
 The must coming from the vat to be refrigerated, falls 
 into a tub divided into two compartments by a vertical 
 partition of wire gauze. 
 
 In the compartment opposite to that receiving the must 
 from the vat, a tube is plunged connected with the bottom 
 of the refrigerator, the suction tube of the pump being con- 
 nected with the exit at the top of the refrigerator forcing 
 the cool must into the vat again. Worked in this way no 
 obstruction can take place, and the machine may work from 
 250 to 300 hectolitres of must without being cleaned. 
 
 The work done by this cooler is naturally a function of 
 the number of divisions of which it consists. Six divisions 
 will suffice for a delivery of 40 hectolitres per hour, with 
 a decrease of temperature similar to that observed in the 
 above experiments. 
 
122 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 The second cooler experimented with is due to Rouviere 
 Hue, a well-known vine-grower of the environs of Mont- 
 pellier. It is especially suitable for small growers, is cheap, 
 and may be constructed by any plumber. These are ap- 
 preciable advantages. 
 
 Apparatus opened out. 
 
 -^^^ 
 
 Fig. 25. Rouviere-Huc's Refrigerating 1 Apparatus. 
 
 The refrigeration is effected by forcing the wine through 
 an annular space, limited by the metallic walls of two con- 
 centric cylinders. The whole system is immersed in a tank, 
 traversed by a constantly circulating current of cold water. 
 
 The annular space is partitioned by projecting metallic 
 plates, alternately overlapping, and forcing the wine to 
 travel alternately from the top to the bottom of the 
 machine. 
 
 The model tried at Balaruc-les-Bains did not give good 
 results, the installation was defective, and did not allow 
 
VINDICATION. 123 
 
 an equitable judgment ; however, the trial enabled us to 
 point out a few weak points of the machine which enabled 
 llouviere-Huc to make additional improvements before the 
 vintage. These, although imperfect, permitted him to carry 
 on further trials in 1896. 
 
 He has been kind enough to communicate the figures 
 obtained, which are very satisfactory. 
 
 f Temperature of wine entering ... 32-0 C. 
 
 1st hour < P ., fc n~ nc,^, 
 
 ( lemperature or wine at exit ... 2o'0C. 
 
 9 ,, J Temperature of wine entering ... 30-5C. 
 
 ( Temperature of wine at exit ... 25 C. 
 
 01, (Temperature of wine entering ... 29-5 C. 
 
 I Temperature of wine at exit ... 24-5 C. 
 
 . , i I Temperature of wine entering ... 28*5 C. 
 
 ( Temperature of wine at exit ... 24-0 C. 
 
 These are for deliveries of wine and water respectively 
 of 18 and 8 hectolitres only, operating on a fermenting vat 
 of 150 hectolitres. 
 
 During the fifth hour, the must at entry being below 
 28 C., the operation was stopped. 
 
 The water pumped from a deep well, had a temperature 
 of 15-5 C. at entrance, and an average of 24 C. at the 
 exit. 
 
 Thirty-two hectolitres of water were used during the four 
 hours, and absorbed about 27,000 calories from the wine 
 in the vat. 
 
 The wine in the vat was reduced after the four hours' 
 circulation to 28 C., which is a most satisfactory tem- 
 perature. 
 
 These are very good results, and no doubt Bouviere's 
 cooler will become a practical machine, when a few addi- 
 tional improvements in its construction render its working 
 more convenient. 
 
 In spite of the results observed one should use the water 
 in a more systematic way, as the working of the machine 
 could only be improved thereby. 
 
 The third cooler experimented upon is due to Andrieu. 
 The principle it is based on differs from the above in this, 
 that it utilizes the refrigerating power of both air and water. 
 
124 
 
 WINK-MAKING IN HOT CLIMATES. 
 
 The machine has a surface of action much more consider- 
 able than the preceding. The wine circulates, as shown in 
 Fig. 26, in an annular space, limited by two vertical 
 cylindrical metallic walls, one in contact with water the 
 other in contact with air. 
 
 Fig. 26. Andrieux Refrigerating Apparatus. A, entrance of wine to be treated ; 
 B, exit of cold wine ; D, entrance of cold water ; C, exit of warm water ; E, annular 
 space in which the wine circulates. 
 
 It is composed of concentric vats similar to the Toute'e 
 metallic vats, the inside vat containing water, and that on 
 the outside the wine to be cooled. The circulation of the 
 liquids is in opposite directions both from bottom to top. 
 
 In this particular instance the outside vats were made 
 of sheet iron covered inside with a varnish unaffected by 
 the wine. They measured 1-18 metres in height and 0*82 
 metres in diameter ; the inside tank was made of tin, T20 
 metre high and 0*63 metre diameter. 
 
 The inside vessel is arranged in such a way that its 
 surface is at a constant distance of 9J centimetres from 
 that of the outside vessel, both at the sides and bottom. 
 
 It is evident that this machine has a very large surface 
 for action, for each division has about 3J square metres of 
 available cooling surface, or 16^ square metres for the three 
 divisions, while the three divisions of Paul's cooler have 
 only 3^ square metres. Again, one should add, to Andrieu's 
 machine, the surfaces at the bottom which also bring their 
 contingent of cooling effect. 
 
 The results obtained with this device were very satis- 
 factory. The decreases of temperature observed were con- 
 fined between 4 and 10 C., according to the initial 
 temperature of the wine entering (between 28 and 37 C.) 
 for deliveries of wine and water comparable to those of 
 Paul's cooler, that is to say, 1^ hectolitres of water for 2 
 hectolitres of wine. 
 
VINDICATION. 125 
 
 Here are the figures relating to the two experiments 
 
 1. Quantity of wine ... ... 16*6 hectolitres per hour. 
 
 Quantity of water ... 13*6 
 
 Temperature of wine at ^ 
 
 entrance ... ... 28'2 C. | Temperature of 
 
 Temperature of wine at exit 23'7 C. [^ the air during 
 Temperature of water at j the experi- 
 
 entranee ... ... 18-2 C. | ment, 20 C. 
 
 Temperature of water at exit 22 C.J 
 
 2. Quantity of wine ... ... 13'5 hectolitres per hour. 
 
 Quantity of water ... 8*64 
 
 Temperature of wine at "] 
 
 entrance ... 38-8 C. j Temperature of 
 
 Temperature of wine at exit 28'0 C. ) the air during 
 Temperature of water at j the experi- 
 
 entrance ... ... 18-5 C. ] ment, 20 C. 
 
 Temperature of water at exit 28*5 C. J 
 
 (Results obtained after two hours' work.) 
 
 Considering the dimensions of the machine the delivery is 
 small. We would have preferred making experiments with 
 larger quantities, but this was not possible, as the section of 
 the exit tubes did not allow a delivery exceeding 16 or 1? 
 hectolitres. 
 
 The results are excellent, the only drawback being that 
 the machine is cumbersome. 
 
 It has the advantage of not being liable to b'ecome 
 obstructed, and the divisions or tanks maybe used when 
 the vintage is over in various useful ways storage of 
 wine, &c. 
 
 The outside vessels hold about 600 litres, the inside ones 
 about 360 litres. 
 
 Vine-growers, therefore, are only embarrassed in choosing 
 a cooler, for apart from those we have described, rather at 
 length, there are a great many others in existence which 
 might prove useful in a number of special cases. Vine- 
 growers should convince themselves of the fact, uncontrover- 
 tible at present, that the maintenance oj 'fermentation at a 
 temperature near 30 C. is a powerful factor in improving 
 the quality of the resulting wines, and they must, therefore, 
 make every ejfort to attain that desirable result. 
 
126 WINE-MAKING IN HOT CLIMATES. 
 
 METHOD OF TAKING THE TEMPERATURE OF A 
 FERMENTING VAT. 
 
 With or without refrigeration, it is always of great interest 
 to the wine-maker, to know the temperature of the vats 
 during fermentation, even if only to follow it and make the 
 wine systematically. This is done by the use of ther- 
 mometers, arranged in a more or less convenient manner. 
 
 It is well to know, to start with, that the temperature 
 varies in different parts of the vat when it is full of vintage 
 in fermentation. It is generally low at the bottom and 
 high at the top, the average temperature being found 
 towards the middle of the liquid zone, below the head or 
 mass of floating marc. It is, therefore, at that point that 
 the temperature should be taken if we desire to know the. 
 average. 
 
 The simplest way is to use an ordinary hand thermometer, 
 graduated on the stem, placed in a groove made at the end 
 of a piece of wood pointed at the end. The piece of wood 
 with the attached thermometer is pushed below the marc to 
 the required depth, and kept submerged in the liquid for a 
 length of time sufficient to allow the thermometer to reach 
 the temperature of the surrounding liquid. 
 
 This method is simple, but the observations are difficult, 
 and not very exact. When an ordinary thermometer, 
 arranged as described above, is used, and the thermometer 
 is drawn out, it passes through cooler surroundings, which 
 reduce 1 the reading on the thermometer too quickly to allow 
 an accurate reading being obtained. 
 
 It is preferable, when an ordinary thermometer is used, 
 to choose one riot too sensitive, that is to say, with a large 
 bulb and large bore. It will be necessary to leave it for 
 some time in contact with the liquid to attain its tem- 
 perature, but it will keep that temperature longer after 
 removal and facilitate the reading. 
 
 Alcohol thermometers are, all things being equal, better 
 than mercurial thermometers for this operation. 
 
 Maximum thermometers, that is to say, those recording 
 the indication of the highest temperature to which they 
 have been submitted, are preferable. Very accurate and 
 sensitive thermometers of this kind are made of the same 
 shape as an ordinary thermometer. 
 
 A process much in vogue, allowing the use of any ther- 
 mometer, consists in drawing from the vat a bucketful of 
 
VINDICATION. 
 
 12' 
 
 the must to be examined ; the temperature remains constant 
 long enough to allow an accurate reading to be taken. 
 This would be an excellent method if the liquid was taken 
 from the centre of the vat, but being drawn from the bottom, 
 it more often than not indicates too low a temperature. 
 Thermometers with stems 
 bent at right angles may 
 be found in commerce ; the 
 bulb is introduced into the 
 the vat or cask at the re- 
 quired height, the stem 
 standing vertically against 
 the outside wall. Fig. 27. 
 The indications are good in 
 this case if the bulb pene- 
 trates far enough into the 
 vat. Unfortunately, the 
 bulb does not generally 
 protrude very far into the 
 vat, so as to provide against 
 breakage, likely to occur 
 through the mass of marc 
 moving suddenly under 
 the influence of the liber- 
 ated carbonic acid gas. 
 
 However, the taking of the temperature in any case is a 
 very delicate operation, and for this reason Houdaille and 
 myself have invented an instrument which is easy to use, 
 and automatically registers the results. 
 
 Self-registering Thermometer of Houdaille and Roos 
 In devising, in conjunction with Houdaille, the self- 
 registering thermometer, which we will now describe, we 
 aimed at placing in the hands of wine-makers an instrument 
 for observation and control, which dispenses with the taking 
 of temperatures, and gives for each fermentation a record, 
 the importance of which will soon be appreciated. 
 
 The object is to have an instrument recording automati- 
 cally, at any hour of the day or night, exact indications in 
 a convenient form for observation. It should be of suffi- 
 ciently strong construction to be handled by workmen in 
 the cellar without danger of breaking, and capable of being 
 introduced or removed from the vat without difficulty ; of 
 
128 
 
 WINE-MAKING IX HOT CLIMATES. 
 
 simple manipulation, and requiring no special knowledge ; 
 not inconveniencing the operations connected with wine- 
 making ; and, finally, not too costly. 
 
 To our knowledge, no thermometers answering all these 
 conditions were in existence previously, and we think that 
 our invention will give satisfaction in each of these respects. 
 
 Our self-registering thermometer consists essentially of 
 a metallic reservoir rilled with alcohol and communicating 
 by a capillary tube with an elastic reservoir filled also with 
 alcohol, altering in shape under the influence of the change 
 in the volume of alcohol, according to the temperature it is 
 submitted to. These deformations are amplified by a lever 
 with a pen attached to one end, used for registering the 
 temperatures. 
 
 It consists of a projecting cylindrical tube, with a conical 
 base of strong tinned copper, of a diameter of 30 m.m., 
 and a length varying from 1^ to 2 metres, according to the 
 depth of the vat,* 
 
 This protecting tube can 
 be dismounted in two parts, 
 joined by a coupling to facili- 
 tate cleaning ; it contains 
 the bulb and capillary tube 
 joining it to the receiver 
 (Fig. 28), fixed on a solid 
 wooden support. The re- 
 ceiver is composed of two 
 discs with concentric un- 
 dulations, soldered on their 
 outside edge, slightly 
 dished, and communicating 
 with the thermometer bulb 
 through the capillary tube. 
 
 The whole system is 
 filled with alcohol, air or 
 gas being carefully ex- 
 cluded. 
 
 The discs, on account of their elasticity, swell under the 
 influence of the increase in the volume of alcohol when the 
 
 Fig. 28. Self-registering Thermometer of 
 Houdaille and Roos. 
 
 * It is desirable that the length of the thermometer be such as to allow the 
 bulb to go underneath the head (of marc), that is to say, about half the depth 
 of the vat. 
 
VINDICATION. 129 
 
 temperature rises, and contract when the temperature falls, 
 on account of their own elasticity as well as the atmospheric 
 pressure. 
 
 The cylindrical thermometer bulb is made of thin copper, 
 and contains about 200 cubic centimetres of alcohol. Jts 
 length is 60 centimetres ; it presents, therefore, a sufficiently 
 large surface for exchange of temperature, to insure sensi- 
 tiveness. 
 
 The sine qua non of effectiveness consists in the perfect 
 filling of the instrument, as the slightest bubble of air or 
 gas would falsify the indications. 
 
 Near the receiver a support for the lever is fixed, con- 
 nected by one end to the discs, and provided at the other 
 with a pen for registering and amplifying the expansions or 
 contractions of the discs. 
 
 The registration is made on a sheet ad hoc, which is dis- 
 placed before the pen by clock-work. 
 
 Contrary to what is generally adopted in self-registering 
 instruments, we have preferred to register the indications of 
 the instrument on a plane, instead of a cylindrical surface. 
 
 This arrangement allows the reading of the complete 
 record to be made at a glance, and facilitates the changing 
 of the recording sheets. We have simply transformed the 
 circular movement of a pinion to a rectilinear movement, by 
 engaging it with a toothed rack, instead of a cog-wheel. 
 
 This toothed rack is fixed in the front part of the brass 
 plate supporting the recording sheet. 
 
 The clock-work is sufficient for one week's continuous 
 record, and insures, therefore, the working of the apparatus 
 during the whole time of an ordinary fermentation. The 
 anchor, or cylindrical escapement, allows its working in any 
 position, and does not necessitate the apparatus being fixed 
 vertically. 
 
 The instrument, as above described, is easily handled, and 
 transportable. It has been carried great distances without 
 special care, and without damage. It may be carried on the 
 shoulder (like a gun), but weighs much less. 
 
 We have no doubt that this instrument will render great 
 service to those who desire to follow or supervise their 
 fermentations, and keep them between recognised limits. 
 
 The form of the curve will show at a glance if the tem- 
 perature rises too quickly, and if it is necessary to 
 refrigerate. The reading of the curve recorded during the 
 
 10649. * 
 
130 WINE-MAKING IN HOT CLIMATES. 
 
 hours when direct supervising might have been defective, 
 will give the course of fermentation during that time, and 
 the proprietor may readily control with it the execution ot 
 his orders, and by ultimately comparing the records of each 
 vat, and the wines resulting from them, get valuable docu- 
 ments on the influence of temperature on fermentations and 
 qualities of wines. 
 
 This self-registering thermometer, although very recently 
 invented, has been improved in many details, rendering it 
 stronger and more symmetrical. 
 
 FERMENTING HOUSE. 
 
 The vintage coming from the crusher reaches directly, 
 after travelling a variable distance, the vessels where 
 fermentation is to be effected. 
 
 The building in which the fermentation is effected is called 
 
 the fermenting house. There is nowadays a great tendency 
 
 , to isolate the fermenting house from the storage or maturing 
 
 cellar. . This arrangement exists in all newly-built cellars, 
 
 but is not an indispensable condition for success. 
 
 Contrary to general opinion, the fermenting house 
 must be very well ventilated, open freely to all winds, and 
 constantly swept by draughts. 
 
 Many think that it is better to use underground cellars for 
 fermenting because they are always cool during hot days. 
 
 This is an error pointed out by Toutee, the inventor of 
 the metallic vat, in the following humorous story 
 
 " I saw the cellar of a large grower, in a hot climate, in 
 course of construction. This grower desired to neglect 
 nothing in order to make it a success, addressing an architect 
 in the following way : ' I want to make wine in - 
 where the temperature is rather troublesome, how can I 
 protect the vats from that temperature ? ' ' Very simply,' 
 answered the architect ; ' begin by sheltering the ground 
 against the solar rays by means of a shed, then excavate 
 the shaded ground, and cover the excavation with masonry 
 vaults, one metre thick, throw over the arches Iwo metres 
 thick of soil, and I guarantee the interior will remain 
 unaffected by exterior temperatures. My charge is so much 
 per square metre excavation, and so much per cubic metre 
 masonry.' ' : 
 
VINDICATION. ]31 
 
 " The question is put in the same terms and solved in quite 
 as smart a way by the vat maker, who says ' To shelter 
 your musts against the sun and hot wind, isolate them in a 
 non-conducting envelope.' 
 
 " Walls of oak (heart wood) 7 to 9 centimetres thick, 
 that is how I make vats, they are sold by weight. 
 
 " Premises and vessels cost the bagatelle of 50,000. 
 
 " Well, imagine the stupefaction of our friend, when, enter- 
 ing his cellar with me, he noticed that the average tempera- 
 ture in Algeria being 29 C. on the 1st of September the 
 thermometer showed 41 C. in his cellar. 
 
 " And I say in his cellar, for his musts were at a much 
 higher temperature. When the poor man made up his mind 
 to take the temperature of his musts by an original method, 
 he found the testing glass in the laboratory recorded 49 C. 
 after ten minutes waiting and various transversations which 
 had made it lose some 4 or 5. 
 
 " It is that the source of the greater heat is not at the 
 exterior of the cellar, but rather in the interior of the vats, 
 and he had obtained a result all the more worthy of compas- 
 sion, inasmuch as he had taken every precaution to prevent 
 all exchange of temperature between the interior and the 
 exterior. Thanks to the 50,000 spent, the must was keeping 
 all the heat developed by the fermentation." 
 
 Under this pleasant form the above account shows per- 
 fectly the inconvenience and dangers of a badly ventilated 
 fermenting house. We advise, therefore, especially small 
 growers, having cellars in town or village, too frequently 
 poorly ventilated, to give up fermenting in cellars. Let the 
 musts ferment outside under a tree or shed, just sufficient to 
 protect the vat from the direct rays of the sun. Let them 
 try only, and the results obtained will convince them better 
 than any argument of the benefit they will gain by adopting 
 this modification. 
 
 FERMENTING VESSELS. 
 
 The vinous fermentation, already briefly described in the 
 first part of this work, is a complex phenomenon capable of 
 being influenced by numerous causes. Some even assert that 
 
 * Hipp. Lecq. De la Fermentation des mouts de Vin A Temperature basse 
 par VEmploi des Cuves Metalliques. Alger. Imprimerie Orientale, Pierre 
 Fontana et Cie, 29 rue d'Orleans, 1894. 
 
 I 2 
 
132 WINE-MAKING IN HOT CLIMATES. 
 
 it is influenced by the shape of the vessel or the nature of the 
 materials the vessels are made of. 
 
 In fact, this influence as well as that of the mass is rather 
 indirect. There are a number of conditions to be realized for 
 fermentation to start well and continue in a satisfactory 
 manner, guarded against alterations liable to occur from 
 parasitic fermentations ; but, those conditions once realized, it 
 is unimportant whether it takes place in wood, stone, brick, 
 cement, wrought or cast iron. 
 
 The vessels usually used for fermenting are 
 
 Wooden vats, conic frustrum shape, open or not at the top. 
 
 Stone vats, generally cubic in shape, open or not, coated or 
 otherwise, with varnish or glazed tiles. 
 
 Brick vats, generally cylindrical in shape, much used in 
 Algeria under the name of anaphoras. 
 
 The vats recently devised, but already much used, of sidero- 
 cement ; that is to say, built of a network of interlacing round 
 iron, about \ inch in diameter, with a mesh of about 2 inches, 
 sunk into a thickness of 2 or 3 inches of cement. They vary 
 greatly in shape. 
 
 Toutee strongly advocates the use of iron vats, usually 
 cylindrical, for hot regions. 
 
 Finally, ordinary casks used generally in all viticultural 
 regions for storage. 
 
 The capacity of the fermenting vessels varies considerably. 
 
 Whatever their shape is, and whatever material they are 
 made of, the vat will suit for fermenting purposes, provided 
 its interior surface be inert, or incapable of producing altera- 
 tions in the taste or chemical composition of the must. 
 
 The vats of masonry or sidero-cement cannot be used 
 without preliminary preparation, but must be purified, with 
 the object of preventing the possibility of their acting on the 
 must. 
 
 The various lime compounds, which always exist in mortar 
 or cement, have an unfavorable influence on wine, and must 
 therefore be eliminated. 
 
 This result is easily attained by washing the inside walls 
 with a solution of sulphuric acid, followed by a coating of 
 silicate of potash, which,* when once dry, is quite unattacked 
 by wine, and has the advantage also of rendering the walls 
 impermeable. 
 
 * Sulphuric acid of 10 per cent, strength and two coatings of a 25 or 30 per 
 cent, solution of silicate of potash. 
 
VINDICATION. 133 
 
 The iron, too, remaining in contact with th.e wine would 
 give it a styptic very disagreeable taste, and even modify the 
 wine so much as to render its conservation impossible. It 
 is absolutely necessary that the whole of the internal surface 
 of the vats should be covered with an impervious coating 
 without action on the wine. 
 
 FERMENTATION. 
 
 If we assume that the physical and chemical conditions of 
 the vintage are suitable, those remaining to be fulfilled for 
 fermentation to take place under good conditions and for the 
 wine to possess its maximum of quality are : 
 
 First Management of the vintage so that the marc be not 
 submitted to alterations through contact with the air. 
 
 Second The drainage of the solid parts of the berry and 
 the marc, obtained by special distribution of the marc in the 
 midst of the liquid or by its lixiviation. 
 
 If fermentation is left to itself without preliminary pre- 
 cautions, the stalks and skins forming the marc, although 
 at first sunk in the midst of the liquid, agglomerate little by 
 little, and being lifted by the carbonic acid gas rise to the 
 surface. 
 
 It is this agglomeration of the solid parts of the grapes 
 which constitutes the head, and a fermentation is said to 
 have a floating head when no special arrangement is made 
 to maintain the marc below the surface, and is said to have a 
 submerged hecid in the opposite case. They are called mul- 
 tiple submerged heads when the marc is subdivided into 
 several parts. 
 
 Generally speaking, the floating head is inferior to the 
 submerged head method, the reasons for the superiority of 
 the latter are of two kinds the marc of submerged head 
 fermentations is always perfectly protected from contact with 
 the atmosphere, and by its arrangement becomes thoroughly 
 extracted by the liquid, while that of a floating head fer- 
 mentation is, so to speak, completely in contact with the air 
 in open vats, and is only partly exhausted by the liquid. 
 
 The action of air on the marc is injurious, even if a quantity 
 of carbonic acid is present. In fermentations where the 
 marc is not at all in contact with the air, volatile acids, 
 especially acetic acid, which characterize defective fermenta- 
 tion, are never produced, while they are always found in the 
 opposite case. 
 
134 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 Pollacci determined these facts by experiments, which 
 consisted in following day by day, and hour by hour, two fer- 
 mentations conducted side by side, according to each method. 
 To strengthen what has been already said we will quote the 
 results of Pollacci's experiments. 
 
 POLLACCFS EXPERIMENTS. 
 
 Fermentations made in glass cylindrical vessels, closed by 
 means of a glass plate, slightly lifted by a cardboard band 
 supported on the edge of the vessels. 
 
 Fermentation withjtoatiny 
 head. 
 
 Fermentation 
 merged head. 
 
 with sul- 
 
 Second Day Evening. 
 
 Fermentation has begun, 
 the space above the head 
 still contains air, for a candle 
 burns in it. The head shows 
 a few moulds, and smell of 
 acetic acid is noticeable. 
 
 Third Day- 
 Lighted candle still burns. 
 More moulds, and acetic 
 acid smell more pronounced. 
 
 Third Day 
 
 Lighted candle ex- 
 tinguished. 
 
 Moulds still increasing. 
 
 Acetic acid can be detected 
 by analysis in the liquid 
 surrounding the marc. The 
 head was rammed down. 
 
 Fermentation in full ac- 
 tivity. 
 
 No trace of moulds or 
 acetic acid. 
 
 -Morning. 
 
 A lighted candle extin- 
 guished when placed in space 
 above head. 
 
 No moulds, no acetic acid. 
 
 -Evening. 
 
 Candle still becomes ex- 
 tinguished. 
 
 No moulds, no acetic acid. 
 
 Fourth Day. 
 
 Same as last. The liquid 
 still contains 140 grammes 
 of sugar per litre. Acetic 
 acid smell not noticed after 
 ramming the head. 
 
 Same as last. The liquid 
 contains only 40 grammes 
 of sugar per litre. 
 
VINIFI CATION. 135 
 
 Fifth Day. 
 
 Same as last. Head 
 
 rammed. 
 
 Same as last. 
 
 Same as last. 
 
 Fermentation continues 
 
 active. 
 
 Sixth Day. 
 
 Fermentation diminish- 
 
 ing. 
 
 Seventh Day. 
 
 Fermentation almost 
 finished. 
 
 . Eighth Day. 
 Fermentation continues. I Fermentation ended. The 
 
 The liquid still contains 35 
 grammes of sugar per litre. 
 
 liquid is clear, cold, and only 
 contains 0*80 grammes of 
 sugar per litre. 
 
 As has been already mentioned, the opening at the top of 
 the glass vessel was very small. It was, however, sufficient 
 to allow the access of air in such proportion as to permit 
 the development of germs, such as mycoderma aceti. 
 
 With the method of keeping the marc out of direct contact 
 with the air, the fermentation is healthier, quicker, and more 
 complete. With a submerged head, even with the must in 
 contact with the air, the moulds and mycoderma aceti germs 
 do not develop, as they do not find a suitable resting place, 
 or because the movements of the liquid constantly wet 
 them, and prevent the direct action of the air. 
 
 Is there not an evident benefit in submerging the head ? 
 For, as has been already said, the suppression of secondary 
 fermentation corresponds to the improvement of the vinous 
 fermentation. 
 
 The interference of the air is not always injurious, being 
 sometimes very useful ; but, as far as the marc is concerned, 
 it is always dangerous, except, however, before the start of 
 the fermentation after crushing. 
 
136 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 Fig. 29. Fermentation with Submerged Hea'J. 
 
 Fig. 3 J. -Fermentation with Multiple Submerged Heads. 
 
 The distinction is 
 therefore well estab- 
 lished in favour 
 of fermentations in 
 which the marc is 
 completely out of 
 contact with the air. 
 
 The immersion, or 
 submersion of the 
 marc, in single or 
 multiple heads is ob- 
 tained by simple de- 
 vices, the following 
 (Figs. 29 and 30) 
 show plainly how the 
 problem can be solved. 
 The arrangement of 
 multiple heads as pro- 
 posed by Michel Per- 
 ret dispenses with the 
 racking of the must 
 for the establishment 
 of the false head, but 
 the results given are 
 not better than those 
 obtained with a single 
 head. The applica- 
 tion of the Ferret 
 method is very 
 tedious. It is neces- 
 sary to place several 
 false heads in posi- 
 tion, and the waste of 
 time is greater than 
 the simple racking as 
 in the previous case. 
 
 We will quote as 
 an ingenious modifi- 
 cation of the sub- 
 merged head system 
 that devised by Coste- 
 Floret, which con- 
 of two vertical 
 
VINDICATION. 
 
 137 
 
 partitions dividing the vat. 
 Fig. 31 very clearly and 
 intelligibly shows it, and 
 dispenses with a detailed 
 description. 
 
 With the Coste-Floret 
 method important advan- 
 tages are evident, but we 
 also notice some slight de- 
 fects the marc will always 
 rise up a little and float, and 
 will always be, though on a 
 very small surface, in con- 
 tact with the air. This is a 
 defect, but it may easily be 
 remedied by fixing a small 
 false head horizontally of 
 the same size as the marc 
 chamber, preventing the 
 marc from rising above the 
 liquid. 
 
 We do not agree with 
 Coste-Floret, that lixivia- 
 tion of the marc results from 
 forcing the must to pass 
 through from one compart- 
 ment to the other. 
 
 In fact, even if the marc 
 can be prevented from rising, 
 it is not possible to prevent 
 a certain free space forming 
 
 between the marc and the bottom of the vat. Therefore, 
 when the must is made to pass from one side to the other, 
 the liquid will naturally travel along the line of least 
 resistance, and consequently pass below the marc without 
 percolating through it. 
 
 We do not see the necessity for lixiviation in the case of 
 submerged fermentation, and a fortiori in the Coste-Floret 
 system. In both cases the surfaces of contact of the must 
 and marc are quite sufficient to allow the latter to give to 
 the wine all the useful principles it contains. 
 
 Fig. 31. Coste- Floret's arrangement. 
 
138 WINE-MAKING IN HOT CLIMATES. 
 
 The advantages of submerged head fermentation lie 
 mainly in the suppression of the injurious action of the air, 
 and the fuller utilization of the solid parts of the grape. 
 
 If we manage to place the marc (although floating) out 
 of contact with the air, and lixiviate it with the must 
 several times, the results will be quite as good, and will dis- 
 pense with the tedious manipulations connected with the 
 immersion of the marc, and we will always be able to stop the 
 extracting action of the must when necessary, by shortening 
 or prolonging the lixiviation. 
 
 In this respect the use of large casks is preferable to any 
 other vessel, on account of their special shape, narrower on 
 the top, preventing the excessive rising of the marc, so that 
 the greater part is kept submerged. 
 
 By taking the precaution of covering the top opening 
 with a board, all access of air is prevented, and the marc 
 surrounded with carbonic acid gas is not liable to the 
 alterations observed in open vats. 
 
 The lixiviation is obtained by pumping the must from the 
 bottom part of the cask or vat to the top, spreading it over 
 the head. 
 
 This distribution of the must over the whole surface of the 
 head is very important. If it is not done carefully a small 
 part of the marc is too strongly extracted, while the rest 
 remains unutilized. 
 
 With a strong jet falling on the head always in the same 
 place, a kind of channel is formed in the marc, through 
 which the must reaches the bottom of the head without 
 distributing through it, and therefore without exerting a 
 solvent action in its passage. 
 
 The proper distribution of the must is easily effected by 
 the use of several little devices, amongst which may be 
 mentioned the hydraulic swivel, and the break jet, which are 
 now used by many wine-makers. 
 
 The hydraulic swivel consists ,of a box around which tubes 
 are arranged horizontally like the spokes of a wheel, and 
 bent almost to right angles in the same direction. The box 
 revolves on a pivot when filled with liquid, on account of 
 the hydrostatic thrust exerted by the jets of liquid. The 
 
VINDICATION. 
 
 139 
 
 adaption of the swivel to the distribution of the must pre- 
 sented several difficulties. These have been successfully 
 overcome by P. Paul. 
 
 Much more simple is the break jet, which we have in- 
 vented for use with a machine automatically distributing the 
 must over the head, and which will be described later on ; 
 although simple, it works perfectly, without inconveniences 
 of any kind. 
 
 The principle consists in placing under the jet, normally 
 to it, and at a small distance from the opening of the tap a 
 disc (Fig. 32) on which the jet breaks, and is transformed 
 into a circle of a diameter varying according to the form of 
 the jet. 
 
 Fig. 32. Break Jet. 
 
 The jet from a pump is not quite continuous, or does not 
 possess the same force constantly, whatever pump is used. 
 The result is, that the breaking of the vertical jet on the 
 horizontal disc will spread in a very large rose while the 
 pump is forcing, and in a small one when the pump is suck- 
 ing, and therefore the whole of the marc will be sprayed. 
 
 The operation of spreading the must over the head is 
 generally done with a pump any pump may be used- 
 coupled on the valve of the cask, if it is not desired to 
 aerate at the same time. If it is considered necessary to 
 
140 WINE-MAKING IN HOT CLIMATES. 
 
 aerate the must before pumping it over the head, it is neces- 
 sary to allow it to fall into a tub placed under the vat, so 
 that it conies in contact with the air. 
 
 To facilitate the aeration Trabut invented a tap (Fig. 33) 
 by which air is introduced into the liquid jet in any quantity 
 required. 
 
 Fig. 33. Trabut's Tap for Aeration of the Must, 
 a. Tube to regulate admission of air. 
 
 Trabut's tap works very satisfactorily, and may be used as 
 an ordinary tap, for the air tube can be completely closed. 
 
 The frequent necessity of pumping the must up for lixivia- 
 tion and aeration, induced several persons to try and obtain 
 the ascension of the must automatically, using the pressure 
 of the carbonic acid gas disengaged during the fermentation 
 for the motive power. The first to try and put the idea into 
 practice was Victor Cambon. The machine he devised has 
 been described in the Pr ogres Agricole* from which we 
 take the following extract : 
 
 " The machine invented avoids the inconveniences of 
 floating head fermentation. 
 
 " It may be arranged in various ways, but the vat requires 
 to be hermetically closed. 
 
 " In the top a manhole is placed for the introduction of 
 the vintage, which should be easily closed hermetically. 
 
 * Progres Agricole et Viticolt- 2nd August, 1891. 
 
VINDICATION. 
 
 141 
 
 If 
 
 " This being arranged, the following is one of the methods 
 that may be adopted : 
 
 "On the top of 
 the vat (Fig. 34) 
 is placed a small 
 wooden tank R 
 of a capacity of 
 about one-twen- 
 tieth that of the 
 vat. A tube T 
 is placed in the 
 bottom of the 
 tank, communi- 
 cating with the 
 top of the vat, 
 and closed by a 
 valve S, the stem 
 of which is con- 
 nected with a 
 lever .oscillating 
 round a point 0,' 
 and bearing a 
 floater F at the 
 other extremity. 
 A long tube U 
 
 Starting from the Fig " ^-Cambou's Arrangement. 
 
 bung-hole at the bottom of the vat throws the liquid into 
 the tank R, a sieve P prevents any skins, &c., getting into 
 the tube U, the vat being filled with the vintage through the 
 manhole H. It is then closed, and fermentation starts, the 
 carbonic acid gas not being able to escape compresses upon 
 the must and marc and forces it upwards through the tube 
 V into the tank R. When the liquid reaches the height of 
 the floater F the floater lifts the valve S, the 'must in the 
 tank falls into the vat, and the carbonic acid gas escapes 
 and bubbles through it. At the same time the tube U 
 ceases to run, the floater sinks and closes the valve, and the 
 same operation goes on again." 
 
 Cambon obtained good results with this apparatus, but 
 it has several defects which we have tried to overcome and 
 will now point out. 
 
 In such a machine the orifice through which the gas is 
 liberated should be independent of that through which the 
 
 
142 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 liquid enters the vat. We must also determine a sudden 
 and complete opening of the two orifices, which should be 
 effected by the movement of the liquid in the tank, but which, 
 when once started, must continue, without the liquid inter- 
 fering. It should happen in the same way for the closing 
 of the valve. 
 
 There are other machines aiming at the same object, but 
 they do not realize the above conditions, and present the 
 same drawbacks as that of Cambon. 
 
 We have tried to solve the problem by means of a simple 
 and strong machine, which has been named fermentation 
 auto-regulator, arranged as shown in Fig. 35. It consists of 
 a brass cylinder tinned inside, on the top of which rest two 
 angle-irons, supporting the whole mechanism. 
 
 A 
 
 E 
 
 Fig. 35. Fermentation Auto-regulator. 
 
 This simple mechanism consists of 
 First A straight lever A B, which is called the principal 
 lever, revolving round a horizontal axis A. 
 
VINDICATION. 
 
 143 
 
 Second A lever bent at a right angle C D E, revolving 
 round a horizontal axle D and having two notches, on the 
 vertical arm D E, we will call this piece double catch. 
 
 Third A small straight lever F G revolving round a hori- 
 zontal axis A which we will call auxiliary lever. Three 
 tubes open into the cylinder, one H is constantly open. It 
 starts from the bottom of the vat and opens into the top of 
 the cylinder. This tube may have any shape that of a worm 
 surrounded with cold water, or of any other system of cooler 
 if it is desired to refrigerate at the same time. 
 
 The other two tubes provided with taps start one I I 1 from 
 the top of the cylinder, the other J J 1 from the bottom. To 
 reach one directly, the other after forming an elbow, the 
 opening of the vat U. They are adjusted in the wooden 
 door, tightly fitting the opening of the vat. 
 
 Fig. 36 shows the 
 arrangement of the 
 three tubes and the 
 machine on the plat- 
 form above the vat. 
 The tube H being too 
 long has been passed 
 around a hogshead. 
 
 A glance at the two 
 figures will enable us 
 to see readily the work- 
 ing of the machine. 
 
 The principal lever 
 is connected at its ex- 
 tremity A, by means 
 of chains to the taps K, 
 and a weight P, suffi- 
 cient to overcome the 
 resistance of the open- AX&&S&&&X 
 ing. At the other 
 
 CXtremitV B Of the Fig. 36. Arrangement of Auto-regulator on the Vat. 
 
 lever, is a counterpoise P, calculated to overcome at the right 
 moment double the resistance of the weight suspended to the 
 taps, and the friction. All the different parts of the machine 
 are worked at definite intervals by the displacement of a 
 floater L, along a vertical rod, in the following manner : 
 The machine being placed over a vat, as shown in Fig. 35, 
 and the vat being hermetically closed, except at the bottom 
 
144 WINE-MAKING IN HOT CLIMATES. 
 
 tap, which is always kept open, the pressure of the carbonic 
 acid gas forces the must through the tube into the cylinder. 
 The result of this effusion of must is to raise the floater L. As 
 follows from Fig. 34, when the floater reaches the weight P it 
 will stop a moment, and as it has an upward pressure greater 
 than the weight P the floater continues to rise until equili- 
 brium is established, releasing the principal lever from the 
 weight P. 
 
 However, the lever will not move for it is kept in position 
 by the lower notch of the double lever ODE. 
 
 The ascent of the floater and the weight P continues till 
 the release R touches the horizontal bar C D of the double 
 lever, displacing it around its axis D, freeing the principal 
 lever, which rocks and is drawn down by the weight P sus- 
 pended to the taps. 
 
 The result of this rocking is the complete and simultaneous 
 opening of the two taps, the pressure in the vat is imme- 
 diately reduced to zero, the delivery of liquid into the 
 cylinder ceases at once, and the tube returning the liquid to 
 the vat starts working as a syphon J J 1 , while the gas con- 
 tinues to be liberated through the tube I I 1 . 
 
 Let us now study the descending movement of the floater. 
 
 The floater with the weight P descends from the moment 
 the tubes are open till the chain to which the weight P is 
 suspended is taut, then the principal lever is in an inverse 
 position to that shown in Fig. 34, and would be drawn 
 down by the weight P if it were not' held up by the upper 
 notch of the double lever ODE, on which its extremity B 
 rests. The weight P is, therefore, only suspended to the 
 principal lever while the floater descends. It is only when 
 the latter, reaching its lowest limit, acts by its weight on the 
 chain of the auxiliary lever, that the notch will move from 
 its position, releasing the principal lever, which is then drawn 
 down, the weight P assumes its original position and closes 
 the taps. We have returned to the starting point, and the 
 movement will continue regularly as above described until 
 the end of the fermentation. 
 
 We may add, to complete this description, that the special 
 break-jet which spreads the must in a circular sheet at the 
 end of the return tube may also, if rendered movable, act 
 as a valve, preventing the carbonic acid gas from escaping 
 through the return tube when the taps are open, as the escape 
 of carbonic acid gas bubbling through the must might cause 
 a loss of liquid. 
 
VINIFICATIOX. 145 
 
 The circulation resulting from the use of this machine 
 renders the mass homogeneous in temperature and composi- 
 tion. It allows the use of refrigeration by interposing a 
 cooler between the vat and the auto-regulator. As for 
 aeration, it may be done by spreading the must delivered 
 in the cylinder, and may be easily suppressed by simply 
 covering the cylinder. The carbonic acid gas remains in it 
 on account of its density. 
 
 ^^fermentation auto-regulator works very satisfactorily. 
 It is excellent if used for cement vats, but we do not advise 
 its use with wooden vats without previously ascertaining the 
 resistance of the vat to the pressure required. 
 
 The increase of pressure brought about is not very great, 
 depending on the height of the auto-regulator above the 
 level of the liquid in the must. But wooden vats often do 
 not stand even that slight increase in pressure. When well 
 built of solid wood, they may support double or treble the 
 pressure required, but it is better to test them previously. 
 
 Masonry, or sidero-cement vats, are always strong enough 
 to allow the use of the auto-regulator without danger of 
 bursting. 
 
 DURATION OF VATTING. 
 
 This means the time during which the must remains in 
 contact with the marc in the fermenting vats. 
 
 It is impossible, a priori, to fix a stated time for this, as 
 it varies according to the nature of the wine it is proposed 
 to make, to the cepage used, to the method of fermentation 
 adopted, the temperature of the vat, and the manipulations 
 the must undergoes during fermentation. 
 
 If fermentation is studied, three distinct phases will be 
 observed, corresponding to the activity of the ferments. 
 The first phase, without external manifestation, corresponds 
 to the multiplication of the ferments. During this period, 
 which is always very short, the sugar is only slightly de- 
 composed, and the production of carbonic acid gas is so 
 small that it remains in solution in the liquid. The second 
 phase, called tumultuous fermentation, corresponds to the 
 maximum activity of the ferments. The decomposition of 
 the sugar is rapid, and the disengagement of carbonic acid 
 gas gives rise to violent bubbling of the liquid. 
 
 The elevation of temperature, which is a function of the 
 quantity of sugar transformed in a unit of time, takes 
 place suddenly, alcohol accumulates rapidly in the liquid, 
 
 10649. K 
 
146 WINE-MAKING IN HOT CLIMATES. 
 
 which gradually becomes less favorable to the work of the 
 yeast. This brings about the third phase characterized by 
 still active but relatively quiet fermentation. 
 
 Each of these phases is of greater or less duration, 
 according to the state in which the grapes arrive at the 
 cellar, and the perfection of the crushing and aeration of the 
 vintage before being placed in the vat. 
 
 As a general principle, the must should be racked and 
 separated from the marc, when the total sugar has been 
 transformed into alcohol. This corresponds approximately 
 to the zero degree of the mustimetre. It is then only that 
 the wine has extracted from the marc all the useful mat- 
 ters, and acquired its maximum quality. This is only true, 
 if all the conditions of fermentation, and especially that of 
 temperature are suitable. 
 
 We may lay down, as a rule, that the higher the tem- 
 perature is the shorter should be the time in the vat. 
 
 Up to 35 C., and for wines of an alcoholic strength 
 not exceeding 10 per cent, by volume, the fermentation 
 starts quickly and is soon finished. If the temperature 
 exceeds 35 C., or even if it does not exceed 35 in the case 
 of wines containing 12 per cent, and over of alcohol, the 
 fermentation becomes retarded, and even stops altogether 
 if the temperature exceeds 35 C. Under these circum- 
 stances, if the means are not at hand for reducing the 
 temperature of the fermentation to 30, it is necessary to 
 rack, whatever degree is indicated by the mustimetre or 
 sweetness remains in the wine. 
 
 Fermentations between 32 and 35 C. are only possible 
 in the case of light wines. These are the only kinds that 
 are not much damaged, because the fermentation goes 
 quickly for two or three days at most, and during the 
 short maceration, the marc cannot affect the surrounding 
 liquid prejudicially. 
 
 In any case, directly the fermentation exceeds 35 C., if 
 refrigeratiou cannot be effected, the wine must be racked. 
 No doubt poor wines result from the latter procedure. 
 They are superior, however, to those obtained by leaving 
 them longer in contact with the marc. They will yield as 
 much alcohol, and have the same freshness andjinesse, and 
 will, after all, command a higher price than the heavy 
 astringent wines of abnormal taste always resulting from 
 prolonged contact with the marc at a high temperature. 
 
VILIFICATION. 147 
 
 The wines called maceration wines are only made 
 successfully in cold countries. The wine may acquire 
 by prolonged contact with the marc at a normal tempera- 
 ture certain qualities demanded by the trade, but at 'high 
 temperatures it only acquires defects. In the South of 
 France the duration of vatting is generally three or four 
 days, but lasts eight days when the temperature does not 
 exceed 30 C. In the latter case the wine is coarser, the 
 dry extract is higher, and the wine produced is richer in 
 colour. The qualities of the colour remain good, without 
 any leaden yellow, depressed, undefinable shades of colour, 
 which always create a bad impression when examined in 
 the tasse* (Fig. 38.) An eight days' 
 vatting, if well conducted gives with 
 Aramon (even if grown on flat land) 
 a wine which many expert tasters would 
 not believe to have been made from 
 Fig. 3B.-Tasse. Aramon exclusively. 
 
 We will not deal at length with the wines called one-night 
 wine. By this expression is meant wines of very short 
 vatting. They have generally more finesse, and are richer in 
 alcohol than the longer fermented wines, but are after all 
 only intermediate between red and white. 
 
 VARIOUS ADDITIONS TO THE VAT. 
 
 ACIDIFICATION. 
 
 We have seen (page 47) the importance attached to the 
 acidity of the vintage, and have shown the amount desirable 
 completed if necessary by means of tartaric acid in order 
 to obtain fine solid wines of good robe (colour, &c.) 
 
 The necessary or useful quantity of tartaric acid to add is 
 calculated from a few determinations of the acidity of the 
 must, and it is placed with the grapes in the crusher, or 
 spread over the vat while it is being filled. Tartaric acid is 
 the only acid that can be recommended for practical use, as 
 it is the only acid capable of fixing the excess of potash as 
 an insoluble combination and liberating the normal acids of 
 the grape neutralized by the potash. 
 
 * A shallow silver or electro-plate cup, the interior bossed in opposite direc- 
 tions, always used by wine judges in examining the colour of wine. See Fig. 38. 
 
 K 2 
 
148 WIXE-MAKING Iff HOT CLIMATES. 
 
 PLASTERING 
 
 Is an indirect means of acidifying the vintage, and consists 
 in spreading over the grapes in the crusher ordinary plaster 
 of Paris (calcium sulphate). This is a very unreliable means 
 of increasing the acidity. The plaster acts on the bitartrate 
 of potash in the must, liberating half the tartaric acid in 
 combination ; but generally the plaster is calcareous, that is 
 to say, containing frequently a large amount of calcium car- 
 bonate which partly, if not entirely, neutralizes the excess of 
 acid resulting from the reaction. 
 
 The reactions of plaster in wine are rather complex. We 
 have shown, in conjunction with Eug. Thomas, that in pre- 
 sence of Jbitartrate of potash, the plaster (calcium sulphate) 
 forms calcium tartrate and acid sulphate of potash, and that, 
 contrary to what is generally admitted, the acid sulphate of 
 potash does not remain as such in the wine. In turn it 
 reacts on the different organo-potassic compounds which 
 always exist in wine side. by side with the bitartrate of 
 potash, and transforms them into neutral sulphates, 
 liberating a part of the acids previously combined as 
 organo-potassic compounds. 
 
 Plastering hastens 4he clearing of wine, and increases its 
 brightness and keeping qualities ; but unfortunately this does 
 not take place without the liquid acquiring a special rough- 
 ness due to the presence of sulphate of potash in solution. 
 
 For plastering to be efficacious it should be done freely. 
 The maximum limit allowed by law (in France), 2 grammes 
 of sulphate of potash per litre, is not. sufficient to enable the 
 method to give decided advantages ; it is extremely difficult 
 to fix a priori the quantity of plaster to be used for the 
 resulting wine to conform to the legal limits. 
 
 It is better to completely reject this method condemned by 
 law, and all the more reasonably, as in commerce plastered 
 wipe is regarded unfavorably. 
 
 PHOSPHATING. 
 
 This practice, due to Hugounenq, is free from some of the 
 adverse criticisms applied to plastering. 
 
 No law prohibits its use. It is recommended by many 
 oenologists, and, as a matter of fact, does not destroy the 
 finesse of the wine. 
 
 Phosphating consists in adding to the vintage pure di-basic 
 calcium phosphate. 
 
VINDICATION. 149 
 
 The chemical reactions taking place after phosphating are 
 of the same class as those occurring in the case of plastering. 
 Tartrate of calcium is formed by the action of the phosphate 
 of calcium on the acid tartrate of potash contained in the 
 must, but it is not yet known which phosphate of potash 
 remains in solution ; however, it cannot be injurious, and the 
 phosphoric acid it contains cannot but have a favorable action 
 on the fermentation. 
 
 The effects of phosphating are the same as those of plaster- 
 ing, with the difference already noted that phosphated wines 
 retain their 'Jinesse, and the phosphate of potash in solution 
 does not affect the taste of the wine to the same extent as 
 sulphate of potash. 
 
 The colour, however, does not seem to be influenced to the 
 same extent in phosphating as in plastering. 
 
 SELECTED YEASTS. 
 
 The addition to the vat of selected yeasts, that is to say, 
 yeasts taken from the lees from grand 'crus, is nowadays 
 practised by a large number of wine-makers. 
 
 The technical science of micro-biology enables us now to 
 take a single cell of good yeast, to cultivate it, guarded from 
 all possible means of contamination, and by using culture 
 mediums specially adapted to their development, to get in 
 a very small volume a number of active cells, infinitely 
 greater than are contained in a large bulk of vintage. 
 
 The object is to insure the rapid predominance of a special 
 vinous fermentation, which will more or less check the work 
 of the ferments natural to the vintage. 
 
 It is the substitution of the work of a special yeast in 
 place of that of the natural yeast. 
 
 The advocates of selected yeasts have greatly exaggerated 
 the advantages resulting from their use, still their use 
 presents some real advantages. 
 
 In fact, well-conducted fermentation with selected yeasts 
 generally gives a slightly superior wine to that obtained 
 from a spontaneous fermentation with the same grapes con- 
 ducted under the same conditions. This is generally admitted, 
 and is certainly important. 
 
 This superiority, however, . is only observed in the case of 
 a well-conducted fermentation, especially as far as tempera- 
 ture is concerned. . 
 
 In short, a more regular and rapid fermentation is 
 obtained, a quicker clearing of the wine, and more highly 
 
150 WINE-MAKING IN HOT CLIMATES. 
 
 developed qualities of preservation. These are results granted 
 by observers to follow from the use of well-selected yeasts. 
 But there is another point, their influence on the bouquet of 
 the wine, which is much debated. 
 
 Many authors, who have studied the question of the use of 
 selected yeasts, have pointed out the action on the bouquet, 
 which is regarded by them as the principal effect. It is 
 presumably even so real, and so developed, that one of them 
 has not been afraid to assert that wort fermented with 
 Chablis yeast had been taken by wine judges for true 
 Chablis. 
 
 We need not point out the evident exaggeration of such a 
 statement. 
 
 The aroma or bouquet of wine must be regarded as the 
 product of numerous factors of two classes. 
 
 The first cannot be modified for a given vintage. They 
 are the cepage, the soil, the subsoil, and the climate. The 
 others depend, perhaps, on the variety of yeast, but more 
 positively on the care and attention given to the vintage, and 
 ultimately to the wine. These may be modified. 
 
 The perfect cleanliness of all the wine-making material, 
 well conducted fermentations, and, later on, opportune 
 rackings have more effect than is generally credited on the 
 final bouquet of wine. 
 
 The study of the action of the different races of wine 
 yeasts is much more complex than that of the various 
 races of beer yeasts. In the latter case we work on musts, 
 which may always be reproduced identically, and even by 
 sterilization cleared from any organisms which might dis- 
 turb the result of the fermentation. These conditions 
 cannot be realized in vinification. We grant that the varia- 
 tions existing between different vintages are slight, but 
 they exist, and in the actual state of our knowledge, how- 
 ever slight these variations may be, no one can say if it is 
 not to them that should be imputed the great dissimiliarity 
 observed between the products of their fermentation. 
 
 If we introduce into the must one of the factors influencing 
 the bouquet, as already explained, we will improve it slightly, 
 but that is all. By using yeast of a particular cru, we 
 certainly make a slight advance, but the advance made will 
 be so much the greater as the grapes used more closely 
 resemble those of that particular cru. This is quite suffi- 
 cient, we consider, to show that it must not be thought 
 possible to make Bourgogne wine with Aramon grapes. 
 
VINDICATION. 151 
 
 We are inclined to think that cultivated yeasts, develop 
 in the wines they produce, an aroma peculiar to each of them, 
 -and which certainly enters in part into the constitution of 
 the bouquet of the wines, issued from the same cms as the 
 yeasts ; but, we emphasize, the aroma given by the yeasts is 
 more often than not a very poor reflection of the bouquet of 
 the grand cms. 
 
 The Champagne yeasts, however, have in this respect a 
 decided effect, the characteristic flavour of champagne (the 
 sugar excepted) is met with in the white wines made in 
 districts remote from Champagne, but fermented with yeasts 
 originating there. There is in this case an undeniable action 
 with regard to the specific flavour which the yeast may com- 
 municate to the wine, and it is to be presumed that Champagne 
 yeast is not an exception, but that all yeasts, to a greater or 
 less extent, act in the same way. 
 
 Whatever this action may be, when it is desired to make 
 wines for immediate consumption (like ours in the South of 
 France), it is not of much importance whether the yeast 
 modifies the future attitude to acquire bouquet or not. 
 
 Selected yeasts seem to furnish straighter, finer wines, of 
 good keeping qualities, and this is quite sufficient to justify 
 their judicious use. 
 
 The study of wine yeasts and of the advantages that may 
 be derived from their application to the different methods of 
 vinification is far from being exhausted. Kayser, Director 
 of the (Enological Station at Mmes, has tried for a longtime 
 to throw light on this obscure question alone or in collabora- 
 tion with Barba. He has already obtained results important 
 enough to justify the hope that by means of selected yeasts 
 (the conditions of life of each race being fixed) still better 
 results than those given to-day may be obtained. 
 
 DE-VATTING (DECUVAGE). 
 
 This operation consists in separating the fermented wine 
 from the marc. 
 
 The de-vatting is very easily done, when the casks are not 
 too far apart, by placing the cask to be racked in con- 
 nexion with the empty cask, and letting the liquid run in 
 by gravitation until it is at the same level in both, and 
 then finishing the operation by pumping. 
 
 The casks which are to receive the newly fermented wine 
 must be thoroughly clean, and washed with an abundance of 
 
152 WINE-MAKIXG IX HOT CLIMATES. 
 
 water, till quite freed from lees. They should not be sul- 
 phured, or if they have been, sulphurous fumes should be 
 completely removed by a current of air. 
 
 The new wine after racking still continues fermenting 
 for a few days, and this must not be checked in any way. 
 The sulphurous fumes act as a decided check on the fer- 
 mentation, and this is so much the greater as the liquid is 
 impoverished as regards its ability to nourish the ferment. 
 
 Contrary to what is usually done, the newly racked wine 
 must not remain more than a week or fortnight in the vessel 
 it has been racked into. After that time, when the 
 fermentation has been well conducted, the wines have 
 deposited, and are ready to be racked into another cask, 
 which should be slightly sulphured. 
 
 It is a common prejudice that sulphuring should not 
 intervene in the fermentation of red wine. This will be dis- 
 cussed later on, but we will state now that this prejudice 
 is without foundation. The practice of sulphuring cannot 
 but have advantages in the case of both red and white 
 wines. It is simply a question of the quantity used. 
 
 EXHAUSTION OF THE MARC. 
 
 The de-vatting leaves in the vat the marc from the vintage 
 it contained. 
 
 The marc still contains after natural drainage a consider- 
 able quantity of wine which should not be lost. It is 
 submitted to pressure. This drains it more or less, and 
 furnishes what is known as." press wine," as compared with 
 the other racked portion known as " taste wine." 
 
 PRESSES. 
 
 The machines used for the extraction of the wine contained 
 in the marc are called presses. They are intermittent and 
 continuous, depending on the method of feeding adopted. 
 
 INTERMITTENT PRESSES. 
 
 In ancient times planks and heavy stones were all that was 
 used, but a very insufficient pressure was the result. It is 
 mainly in the direction of presses that mechanical skill has 
 been directed during centuries in the cellar, and the ancient 
 type, with a few modifications, in detail, is still the most 
 widely used. 
 
 The press actually used consists essentially of three parts. 
 A vertical screw, a horizontal table or base supporting the 
 
VINDICATION. 
 
 153 
 
 screw in the centre, and a nnt travelling on the s crew con- 
 stituting the compressing part. (Fig. 39.) 
 
 -- The marc to be pressed is 
 spread over the table, some- 
 times supported at the sides 
 by a screen surmounted by a 
 cap, and a number of cross 
 pieces called the load, which 
 transmits to the mass, distri- 
 buting it evenly, the pressure 
 obtained by tightening the 
 travelling nnt. 
 
 The compression is obtained by means of levers varying 
 in shape, some worked in one direction only ; others, the most 
 commonly used, -worked with an alternating movement, but 
 forcing the travelling nut to revolve always in one direction 
 by means of a ratchet reversing the movement. 
 The table is made of wood, iron, or cement. 
 
Io4 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 Those made of wood would be excellent if it were not 
 rather difficult to make them staunch and impervious. Those 
 made of iron are very good, but should be coated to prevent 
 the wine acquiring a bad taste by contact with the metal ; 
 those of cement built on strong concrete are practically ever- 
 lasting. 
 
 The load of the press should always have a certain elas- 
 ticity, as it constitutes a pressure accumulator. 
 
 If we consider the marc surmounted by a non-elastic load, 
 when once the pressure limit of the machine is reached we 
 would have to continue applying pressure unceasingly to 
 obtain good results. With an elastic load the press may be 
 left to itself, for the pressure continues to act through the 
 restitution of the force accumulated in the elastic load. The 
 time that the press can be left to act alone is proportionate to 
 the deformation of the load under the given pressure. With 
 regard to this, wooden loads are superior to those of iron. 
 
 The substitution of powerful steel springs placed between 
 the cap and the nut is a decided improvement in intermit- 
 tent presses, this suggestion is due to Crassous (Fig. 40).* 
 
 Fig. 40. - Press with spring load. Crassous Arrangement. 
 
 * This idea was first realized in practice by P. Paul, who manufactures these 
 presses. 
 
VINDICATION. 155 
 
 The load is dispensed with but not its useful effect, which 
 on the contrary is amplified; the cap is fastened to the bolt 
 by a very simple device and they travel together. This 
 greatly simplifies the working. But where the main advan- 
 tage comes in, is in the action of the springs. These are of 
 the same type as those used for railway-carriage buffers. 
 Their normal limit of compression is 20,000 kilos, for a 14 
 or 15 centimetre stroke. 
 
 The height of the marc on the table diminishes under the 
 pressure till its resistance equals the compressing resistance 
 of the springs, if from that moment the tightening is con- 
 tinued the pressure is accumulated in the springs, which 
 become more and more compressed, and is restituted by them 
 when the tightening ceases, the cap continuing to descend 
 till the springs liave expanded to their normal length. 
 
 The stroke is about 14 or 15 centimetres, and this allows 
 a long enough interval for workmen to attend to other 
 operations in the cellar. 
 
 While an ordinary press with a wooden load requires re- 
 tightening every quarter of an hour, presses fitted with 
 -accumulating springs continue acting from two to six hours, 
 according to the pressure and the state of the marc. 
 
 The number of springs varies with the surface to be 
 pressed, and the surface itself varies according to the pres- 
 sure we desire to obtain. 
 
 Generally the marc is cut afresh at the sides to a dis- 
 tance of about 30 or 40 centimetres in from the circum- 
 ference, as the case may be, and thrown over the cake 
 again, and the pressing continued. The pressure is the 
 same, but as it is distributed on a small surface it is much 
 greater per unit of surface. 
 
 All presses dry the marc to about the same extent, the 
 perfection of work depends much more on the way it is 
 done than on the type of press employed. 
 
 The opinions of many specialists have led wine-makers 
 to try and obtain unnecessarily high pressures. 
 
 The yield of juice from a given quantity of marc depends 
 on two factors the pressure and the time during which it 
 acts. The second of these factors can in no way be substi- 
 tuted for the first. It is better to leave the marc longer in 
 the press, submitting it to a moderate pressure, than sub- 
 mitting it to a powerful pressure for a short time. 
 
156 WINE-MAKING IN HOT CLIMATES. 
 
 This method of operating requires the use of a number of 
 small presses, or of a lesser number of presses capable of 
 receiving a large volume of marc. 
 
 Both large and small presses have their advocates, the 
 superiority of either type is far from being admitted; generally 
 from comparative observations we consider that large surface 
 presses are preferable. Their working is simpler and the 
 marc quite as dry as that worked with machines of smaller 
 surface. We know many cellars where the presses are large 
 enough to receive the marc from a 4oO-hectolitre (9,900- 
 gallon) vat, each dries that quantity of marc without cutting 
 the cake in 24 hours. Therefore, without any work beyond 
 the filling, tightening, and emptying, the draining of the 
 marc is quite as satisfactory as that obtained in less time, 
 with one or two cuttings. 
 
 CONTINUOUS PRESSES. 
 
 Ordinary presses, such as those above described, give medium 
 results, even the best of them, that is if there are any better 
 than others. The drainage of the marc is far from being com- 
 plete, as it always retains at the end of the operation about 
 60 per cent, of liquid. Is it desirable to go to any further 
 trouble, and will we not by an increase of pressure augment 
 the yield at the expense of the wine ? We do not think it is 
 desirable, but the advocates of continuous presses are of this 
 opinion, for they quote amongst the advantages of these 
 machines a more perfect exhaustion or drainage of the marc. 
 
 In short, continuous presses have been invented with the 
 objects 
 
 First To reduce labour. 
 
 Second To reduce the stock of machinery by dispensing 
 with the use of ordinary presses, which, to treat an equal 
 quantity of vintage, are more numerous and expensive, and 
 above all more cumbersome than continuous presses. 
 
 Third To reduce the time of pressing. 
 
 Fourth To increase the yield of press wine. 
 
 We must at once state that the increased yield aimed at 
 is not yet proved to be attained. All the continuous presses 
 known (with a few rare exceptions), although widely different 
 in shape, depend on the same principle. 
 
 They are composed of two or more cylinders, worked as 
 crushers if fresh vintage is to be treated, or as light compres- 
 sors if fermented vintage is to be dealt with. 
 
VERIFICATION. 
 
 157 
 
 After passing through these cylinders the vintage is carried 
 on by an Archimedean screw, accumulating it in a perforated 
 horizontal cylinder, the diameter of which decreases towards 
 the exit, and is terminated hy an orifice small enough for the 
 marc to form a compact cake or stopper, which can only be 
 expelled under considerable pressure. A fresh quantity of 
 marc replacing that expelled acts in turn as a stopper, and 
 so on as long as the machine is fed. (Figs. 41 to 45.) 
 
158 
 
 WINE-MAKING IN HOT CLIMATES. 
 
VINDICATION. 
 
 159 
 
160 
 
 WINE-MAKIXG IN HOT CLIMATES. 
 
 ' ' ' ' 
 
VINDICATION. 1(51 
 
 Fig;. 45. Self-acting Carrier of Pepin's Press. 
 
 The cylinder may be of conical shape and composed of steel 
 blades, allowing the diameter of the exit from the cone to be 
 increased or diminished by means of a movable iron collar, or 
 it may be as in the Debonno press (the first invented) a tube 
 of rectangular section, with the angles rounded off, closed 
 at its extremity by an adjustable roller, the axis of which is 
 horizontal and perpendicular to the axis of the Archimedean 
 screw, rising under the pressure of the marc, and offering a 
 resistance, which may be varied by means of weights carried 
 on one or two levers connected with the roller. 
 
 The use of continuous presses is particularly tempting in 
 the manufacture of white wine, for it is necessary in this case 
 to obtain in the shortest time, a separation of the liquid and 
 solid parts of the fruit, as completely as possible. 
 
 There is unfortunately in the working a notable defect the 
 yield in juice is apparently greater than that furnished by 
 an ordinary intermittent press, but the must furnished is 
 infinitely more turbid, owing to the greater disintegration of 
 the vintage, to such an extent that if we want to know the 
 true yield of grape juice, it is necessary to separate from the 
 liquid obtained from the continuous press, a quantity of solid 
 matters in suspension, which cannot be regarded as juice. 
 This quantity is great enough to reduce the true yield of juice 
 to even less than that obtained by means of an ordinary inter- 
 mittent press. 
 
 And what is more, the pressure on the marc being equal, 
 the wine obtained by the continuous press has less finesse 
 than that obtained from the use of an intermittent press. 
 
 Whatever be the mode of action of a continuous press, 
 while travelling from the entrance to the exit the marc is 
 
 10649. 
 
162 WINE-MAKING IN HOT CLIMATES. 
 
 submitted to an energetic friction against the internal sur- 
 faces of the machine ; disintegration of the stalks, seeds, and 
 skins, often very pronounced, results from this friction. 
 The organic juices contained in the cells of those organs 
 pass entirely into the wine, and, as we have shown, when 
 describing the crushers, it is important to leave two elements 
 of the grapes (stalk and seeds) intact. The continuous presses 
 at present known do not overcome these inconveniences. 
 
 If we are dealing with white wine, this inconvenience is 
 still more apparent. We do not know any continuous press 
 capable of extracting from red grapes a quantity of white 
 must equal to that obtained by an ordinary crushing, followed 
 by the usual pressing, without the must 'in the former case 
 being more coloured than the latter. This fact is quite 
 unexpected, for it is generally admitted that the most im- 
 portant factor of the non-colouration of the must depends 
 on the rapidity with which the grapes are treated. 
 
 It is a factor, it is true, but not the only one to be con- 
 sidered. It is generally admitted that the colouring matter 
 of the berry is only soluble in concentrated or diluted alcohol, 
 and that if we avoid fermentation the colouring will not 
 occur. The colouring matter contained in the cells does not 
 pass through the membrane while they are surrounded by 
 non-alcoholic must, but if we place in the white must broken 
 cells full of colouring matter, the colouring matter, although 
 completely insoluble in the must, will diffuse through it in 
 very minute particles, which it will be impossible to sepa- 
 rate ; but, what is more, if the insolubility of the colouring 
 matter is admitted as long as it is protected by the cellular 
 membrane, it is not so when the colouring matter is bare 
 and exposed to the action of the must. Duclaux has estab- 
 lished, by a few experiments, that the colouring matter can- 
 not be considered as insoluble in the must, but that this 
 liquid has not got the power of dissolving it through the 
 cellular envelope. 
 
 These various inconveniences delay the general adoption 
 of continuous presses in the viticultural industry. We hope 
 that constructors will be able in the future to .overcome 
 them. Continuous presses will then, and only then, become 
 machines for general use, owing to their advantages, hence- 
 forth irrefutable. 
 
VINDICATION. 163 
 
 EXHAUSTION OF THE MARC WITHOUT PRESSES. 
 
 Presses are far from giving every satisfaction, and the 
 marc treated by them has to be submitted to new manipu- 
 lations to make piquettes, or marc spirit, if it is desired to 
 utilize the wine they still contain. 
 
 AVe studied in collaboration with M. Semichon, Director 
 of the QEnological Station of the Aude, various means of 
 increasing the yield of pure wine from fermented marc, and 
 cannot do better than quote the following extract sum- 
 marizing our researches on this subject : 
 
 " Under ordinary conditions, in the vinification of red wine, 
 the marc remaining in the vat after the racking of the 
 wine, is placed in the press and submitted to a more or 
 less greater pressure, during a varying period. 
 
 " It is thought that by this operation, all, or at least a 
 greater part of the wine contained in the marc is extracted. 
 
 "Pressure, however, does not give as complete an ex- 
 traction as is generally thought, for if we determine the 
 quantity of the wine left in the marc after the operation as 
 conducted under ordinary circumstances we always find a 
 minimum of 50 per cent, of the weight of the marc. Dis- 
 tillers know that they generally extract from 100 kilos, of 
 compressed marc a number of litres of alcohol equal to a 
 little more than half the alcoholic degree of the wine fur- 
 nished by that marc. 
 
 "It is therefore an important fraction of the total yield 
 that might be used as wine, for if we admit that the pro- 
 duction of one hectolitre corresponds to a quantity of 15 to 
 20 kilos, of compressed marc, it is (taking the minimum of 
 50 per cent, of wine remaining) a volume of 7 or 10 litres of 
 wine which may be used for making piquette or marc spirit. 
 
 " This is an important loss, which shows that presses are 
 not perfect instruments as far as yield is concerned. They 
 are not perfect either with regard to the quality of the wine 
 they yield. Every wine-maker knows the defects of press 
 wines in regard to their organoleptic value and keeping 
 qualities. 
 
 " The improvements made in recent years in the manu- 
 facture of piquettes induced us to apply to the exhaustion of 
 impressed marc the method which actually gives the best 
 results for piquettes, and which consists in methodically 
 displacing the liquid impregnating the marc by an ascending 
 current of water. 
 
 L ^ 
 
164 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 " By causing the liquid piston of ascending water to 
 displace the wine, we thought that the yield would be 
 greater than that of any press. 
 
 u An almost integral 
 mechanical displacement is 
 possible, and can be demon- 
 strated by a simple laboratory 
 experiment. 
 
 " If in a flask full of wine 
 we allow a current of water 
 to slowly flow in to the lowest 
 part, the wine is lifted by the 
 water, while the line of de- 
 marcation of the two liquids 
 remains sharply defined if the 
 experiment does not last too 
 long. If the wine is collected, 
 we notice that the diffusion 
 zone is very narrow, and that 
 the alcoholic strength of the 
 liquid experimented upon 
 becomes only appreciably 
 lower in the last portion col- 
 lected. In an experiment 
 made with a flask of three 
 litres capacity (Fig. 46) filled 
 with wine of 1O4 per cent. 
 
 I 
 
 46. 
 
 alcohol, we gathered : 
 1 litre, containing 1O4 per cent, of alcohol. 
 
 1 
 
 500 c.c. 
 300 
 
 400 . 
 
 10-5 
 10-3 
 10-05 
 
 3-51 per cent., average of 
 eight trials of 50 c.c. each. 
 
 " The three litres of wine experimented upon contained 
 312 c.c. of pure alcohol, and the displacement gave 
 
 104 c c. of pure alcohol with the 1st litre. 
 
 105 
 51;5 
 31-5 
 14-04 
 
 2nd 
 
 500 c.c. following. 
 
 300 
 
 400 
 
VILIFICATION. 165 
 
 " A total of 306-05 c.c., which shows a loss of 2 per cent, 
 only. 
 
 " 95'5 per cent, of the alcohol has been extracted in the 
 shape of pure wine equal to that experimented upon, that is 
 to say, of 10'4 per cent, alcohol. 
 
 " It will be noticed that in this experiment the second 
 litre is of higher alcoholic strength. This difference is small 
 enough to be attributed to an error of determination. We 
 do not believe it, however, for we have always noticed this 
 slight increase of the strength in the numerous experiments 
 made. We are unable to explain this constant fact, and 
 can only record it, pointing out that its constancy cannot 
 be explained as a mere coincidence. 
 
 " This shows, when dealing with liquids alone, that it is 
 possible to displace, without mixing, and without any other 
 help than water, more than 95 per cent, of the wine con- 
 tained in the vessel. Will the experiment be as simple if 
 the wine to be displaced impregnates a spongy more or less 
 continuous mass such as marc ? 
 
 " Evidently not, for new factors come into play. We must 
 differentiate between the wine simply wetting the exterior 
 of the tissues, and that contained in the tissues. 
 
 u The former is displaced almost as easily as in the case of 
 liquids, the latter can only slowly come out of the tissue by 
 a kind of dialysis through the membrane of the cells, or 
 even through the skins, if we have to deal with badly- 
 crushed vintage. 
 
 " We made several displacement experiments with solid 
 matters, porous or otherwise, such as broken glass, cotton, 
 sponge, pumice stone, &c., saturated with wine, which showed 
 very quickly that we could not hope for as good results as 
 in the case of liquids alone. 
 
 "We merely quote the results of these experiments as 
 references, and did not stop to study them completely, as the 
 marc alone interested us. 
 
 " The causes which prevent us obtaining an integral 
 yield in the displacement method applied to grape marc, 
 are 
 
 1st, The diffusion or mixing of the wine and water. 
 2nd. The difficulty the wine encounters in traversing 
 the walls of the tissues by a kind of dialysis. 
 
166 WINE-MAKING IN HOT CLIMATES. 
 
 " We determined by numerous experiments, under varying 
 conditions, the rapidity of the diffusion of wine in water. 
 We will not insist on the results obtained, but draw the two 
 following conclusions : 
 
 1st. There is an advantage in having a rapid displace- 
 ment, that is to say, an ascensional rapidity of 
 the liquid piston amounting from 8 to 10 centi- 
 metres per hour. 
 
 2nd. There is an advantage in operating on the marc of 
 well-crushed vintage. 
 
 " In the laboratory we obtained, on small quantities of 
 marc it is true, a yield of pure wine notably higher than 
 that given by the presses. 
 
 " In current practice, however, the marc cannot be treated 
 with the same care that is possible in a laboratory experi- 
 ment, but by modifying the arrangement, and by increasing 
 the number of displacement tanks and arranging them in 
 batteries as is already done for the diffusers in certain 
 industries, we may expect a satisfactory enough yield for the 
 process to remain applicable. 
 
 " The experiments were made on a large scale, but not, 
 however, large enough,* and it will not be possible to do this 
 till next vintage. 
 
 "With four displacing tanks, each holding 100 kilos, of 
 marc, we obtained results comparable with those of the 
 presses. (44*4 litres of pure wine per 100 kilos, of drained 
 marc, while 45 litres were obtained with the presses, that 
 is to say, about 65 per cent, of the wine contained in the 
 marc.) 
 
 " We think that these results would already be ad- 
 vantageous, for they dispense with the labour of pressing, 
 and give an equal yield ; but the course of the operation 
 enables us to foresee that by doubling the number of tanks, 
 or even by taking six only, the yield in pure wine would be 
 increased, and reach that of the laboratory experiments made 
 on the marc, that is to say, about 85 per cent, of the total 
 wine contained in the rnarc. 
 
 " We must add that the quality of the wine so obtained 
 is superior to that of press wine. It has not the same 
 
 * With a sufficient number of tanks (eight or ten) we might greatly increase 
 the ascensional speed of the water. 
 
VILIFICATION. 167 
 
 harshness resulting from the crushing of the organic tissues, 
 neither its defects of preservation resulting from the im- 
 purities in suspension in the liquid. 
 
 "The quantity of wine to be utilized in the shape of 
 piquette or spirit, will be reduced to 3 per cent, in place of 
 7 or 10 per cent. 
 
 " We used in our experiments the following arrangement: 
 Four tanks made from casks with the heads knocked out, of 
 about 120 litres capacity, provided with a screen forming a 
 false bottom, were placed in communication in such a way 
 that the liquid entering in the bottom and centre of the first 
 one, overflowed by a side aperture in the upper part, to 
 pass into the second tank, where it penetrates into the 
 middle of the bottom, and so on. 
 
 " The four tanks so arranged were charged with marc, and 
 the displacing commences ; at the third we might have 
 already drawn pure wine, but we only did this at the fourth 
 at the rate of 45 litres per 100 kilos, of vintage. The first 
 tank is then considered as exhausted, the slightly pink- 
 coloured water it contains is racked and sent back to the 
 water tank, while the feeding is made directly on the second 
 tank, which now becomes the first ; charged with fresh marc 
 the vat we have just finished with becomes the fourth, and 
 so on, each cask becoming in turn the first and last of the 
 system. 
 
 " The limited quantity of water which remains at the end 
 of the operation in the shape of piquette may serve to 
 extract the wine from an unlimited quantity of marc. 
 
 " We consider that a battery of eight tanks would give 
 much better results, the working would be the same as that 
 described ; it might be facilitated, however, by adding a 
 ninth tank, for the charging and discharging to be made 
 without stopping the displacement operations. 
 
 " The zone of diffusion of wine and water is spread over 
 the first two or three tanks, and is preceded by a volume of 
 pure wine, sufficiently extended to allow it to be collected 
 without any admixture of water. 
 
 " This diffusion zone is so much the greater as the vintage 
 is less crushed, we even think that this factor (perfection 
 of crushing) is so important that the method would be in- 
 applicable in the case of an uncrushed vintage. 
 
 " We tried to obtain a more rapid and better displace- 
 ment by the use of a liquid denser than water, and with 
 
168 WINE-MAKING IN HOT CLIMATES. 
 
 that object worked with solutions of common salt of strength 
 varying between 1 and 10 per cent. The yield in wine is 
 not increased, and it has the inconvenience of leaving tails, 
 that is to say, portions of piquette too salty to be of any 
 use. 
 
 " We do not pretend to have made conclusive experi- 
 ments on the subject, and we propose to complete them 
 during next vintage, out such as they are they enable us 
 to lay down the principles of a method of exhaustion of 
 marcs more satisfactory than that depending on compres- 
 sion." 
 
 Since the publication of this work, M. Semichon and my- 
 self have secured the co-operation of several vine-growers 
 desirous of experimenting with a method which, while 
 dispensing with the work of the presses, would give a 
 better result in yield of pure wine, We hope after the 
 next vintage (1898) to be able to definitely establish the 
 superiority of diffusion over pressing by the figures obtained 
 in operating on large quantities. 
 
VINDICATION OF WHITE WINE. 169 
 
 CHAPTER V. 
 
 VINDICATION OF WHITE WINE. 
 
 ^ viuification of white wine differs essentially from that 
 of red wine, in the fact that the transformation of the must 
 into wine takes place without contact with the solid parts 
 of the grape. 
 
 There are two cases to be considered 
 
 Vinifi cation of the grapes of white cepages. 
 Vinification of the grapes of coloured cepages. 
 
 The white cepages, most commonly cultivated for the 
 manufacture of white wine in the south of France, are the 
 Picpoul, Terret-Bourret, and Clairette. 
 
 All red grapes are eligible for making white wine, except- 
 ing ^ the Tinto varieties and Bouschet hybrids (having red 
 coloured juices). 
 
 VINIFICATION OF WHITE VARIETIES. 
 
 Is much simpler than the vinification of red cepages. It 
 consists in crushing the grapes, draining them, placing the 
 drained marc in the press, and leaving the juice from both 
 the above operations to ferment. However, there are certain 
 operations that may improve the finesse and keeping 
 qualities of the wine, and therefore increase its value. 
 One of these operations is the debourbage (settling). 
 
 This consists in separating the suspended impurities. 
 Various methods have been proposed for the debourbage 
 simple filtration, the application of which is much too 
 expensive, the must offering great resistance to filtration ; 
 centrifugating, the effectiveness of which has not yet been 
 sufficiently proved ; and the simple separation by deposition 
 and consecutive packings, the best, most practical, and least 
 expensive of all. 
 
 It is necessary, in order to obtain complete deposition, to 
 maintain the liquid perfectly still during a sufficient time, 
 that is to say, to prevent the liquid from starting to fer- 
 ment. 
 
 Low temperature would be a good means of resolving 
 this 'question or problem, but would be rather costly. E. 
 Thomas and myself studied a scheme applicable to a daily 
 quantity of 500 hectolitres, and we arrived at the conclusion 
 
170 WINE-MAKING IN HOT CLIMATES. 
 
 that the required result could only be obtained at an extra 
 expense of 2 francs per hectolitre, evidently incompatible 
 with the value of the product to be made. 
 
 There is fortunately an excellent and cheap means of sus- 
 pending the fermentation during the required time. This 
 is by sulphuring. 
 
 The gas produced by the combustion of sulphur (sulphur- 
 ous anhydride, S0 2 ) is very soluble in water and must, 
 and has the property of arresting the reproduction of the 
 yeast and rendering it inactive during a certain time with- 
 out killing it, if the amount used is not too great. 
 
 It is the exact gauging of the sulphurous acid absorbed 
 which is the important point in the application of the 
 debourbage. 
 
 We must use sufficient sulphurous acid for the deposition 
 to be complete, and yet a small enough amount for the 
 inactivity of the yeast to cease directly the separation, of 
 the lees has taken place. 
 
 Experiments have shown that an amount of sulphurous 
 acid corresponding to O01 per litre of must does not greatly 
 retard the commencement of fermentation. A quantity of 
 O03 retards the fermentation for 10 or 12 hours. With 
 O'Oo it is retarded for 18 to 24 hours, and with 0*075 it 
 is retarded from 48 to 60 hours. With O'lO the fermentation 
 only starts five or six days after treatment. We can, there- 
 fore, retard at will the start of the fermentation by simply 
 introducing into the must the above-mentioned quantities. 
 
 It is not very easy to gauge the absorption of the exact 
 quantity of sulphurous acid resulting from the combustion of 
 sulphur. This is why we are often liable when using imperfect 
 apparatus to sulphur too strongly, which retards the fermen- 
 tation indefinitely, and therefore the selling of the wine, or 
 not enough, in wliich case the fermentation starts before the 
 debourbage is completed. One or other of these defects is 
 frequently observed when the operation is simply performed 
 in a previously sulphured cask. 
 
 We studied some years ago the application of various 
 definite compounds to replace sulphuring the alkaline sul- 
 phites, the alkaline earthy sulphites capable of being decom- 
 posed by the must, and yielding for a given weight, a constant 
 quantity of sulphurous acid. The results were excellent, but 
 it is difficult to obtain in commerce at reasonable cost, suffi- 
 ciently pure chemicals to be used in vinification, and in 
 
VINDICATION OF WHITE WINE. 
 
 171 
 
 practice the homogeneous admixture of a small quantity of 
 matter with large quantities of liquid is always difficult to 
 realize. 
 
 Sulphurous acid diffuses more easily in the must than 
 the solid sulphites, therefore we have preferred to use it and 
 to find practical means of charging the liquid with the 
 desired quantity only. 
 
 The application of sulphurous acid to the must is called 
 mutage (numbing), a name originating from the effect it 
 produces, rendering the must muet (numb). 
 
 The machines used for this operation are called muteuses, 
 mutoises, mutoirs. 
 
 The mutage, in view of obtaining dry white wines, is only 
 temporary, and requires much less sulphurous acid than in 
 the case of the must being required to remain sweet, for 
 making ultimately concentrated must, grape syrup, or ports. 
 
 The ordinary muteuse Consists of a vessel in which the 
 must travels in one direction, and air charged with sulphurous 
 acid in the opposite direction. 
 
 Such for instance is the muteuse of Coste-Floret (Fig. 47). 
 The must arrives by the tube a, falling in a spray in the 
 muteuse C, through the perforated plates A B, and absorbs 
 during its passage the vapours generated by the stove E. 
 
 . 47. - Coste-Floret's Muteuse. 
 
172 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 The must itself forms a liquid joint in the bottom of the 
 tub D, it is then taken by the suction tub b of the pump F, 
 and pumped back by the tube c (b.e.). 
 
 The muteuse of P. Paul shown in Fig. 48 is almost as 
 simple. It consists of a box 1 metre 30 c.m. high and 
 40 c.m. wide. The must arrives at the upper part and falls 
 on oblique superposed partitions. It is therefore exposed 
 on a large surface to contact with the vapours charged with 
 sulphurous acid coming from the stove. 
 
 ENTRANCE OF MUST TO BE TREATED 
 
 Fig. 48. Paul's Muteuse 
 
VINDICATION OF WHITE WINE. 
 
 173 
 
 These two machines may insure the complete dissolution 
 of the sulphurous acid furnished by them, but cannot be 
 considered as capable of gauging- the absorption of the sul- 
 phurous acid with precision, for it is very difficult, not to 
 say impossible, to furnish them with exactly the required 
 q uantity of sulphurous acid. 
 
 The weight of sulphur burnt in a given time is a function 
 of the speed of the current of air, and the speed for the same 
 aperture of the valve varies greatly from one operation to 
 another, even at different times during one operation. 
 
 The sulphuring cylinders used at Villeroy by the Com- 
 pagnie des Salins du Midi, which work in a similar way to 
 the two muteuses described above, have the same defects. 
 At their vineyards at Bosquet the Compagnie des Salins du 
 Midi use a different apparatus allowing more exact measure- 
 ment. 
 
 The muteuse used at Bosquet consists of a sidero-cenient 
 chamber d (Fig. 49) in which the necessary weight of 
 
 EcKeYle 
 
 Fig. 49. Bosquet's Muteuse. 
 
174 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 sulphur is burnt (half the weight of the sulphurous acid 
 required) in the shape of sulphured cloth suspended to the 
 cloth carrier S, which can be raised or lowered. The cham- 
 ber is then filled with must, and when the gas is absorbed 
 the valve V is lifted and allows the must to flow into the 
 debourbage tank below. 
 
 With this apparatus fairly accurate measurement and 
 absorption can be effected, but it is very complicated. 
 
 With the exception of the Bosquet muteuse, which cannot 
 be used in small cellars, the machines above described only 
 give, an illusory measurement. 
 
 Eugene Thomas attempted to substitute an apparatus 
 allowing the measurement and absorption, by direct sul- 
 phuring of the vat to be filled with must, the idea being to 
 prevent the air which is driven out when filling the vat 
 from carrying away with it any sulphurous acid. 
 
 N 
 
 
 B 
 
 A 
 
 Fig. 51. 
 
 Fig. 50. 
 
 This was realized simply by using 
 a kind of funnel, forming a liquid 
 joint by means of two systems of 
 tubes, one for the entry of the must, 
 the other for the air exit. The dia- 
 grams (Figs. 50 and 51) give an 
 idea of the arrangement of the 
 machine. 
 
 It works fairly well, but not per- 
 fectly. The washing of the gas is 
 done rather spasmodically, which 
 leads us to fear it operates imper- 
 fectly. For this reason we tried, in 
 conjunction with Thomas, to improve 
 the apparatus. 
 
VILIFICATION OF WHITE WINE. 
 
 175 
 
 The modified apparatus consists of three parts, capable 
 of being dismounted and fitting together (see Fig. 52).* It 
 consists of 
 
 A. A cylindrical vessel of the same diameter as the 
 
 manhole ; the cylinder carries at its top a hori- 
 zontal flange resting on the edge of the man- 
 hole, to which it is luted with plaster. The 
 annular part at the bottom has a space of 8 to 10 
 centimetres between the concentric rings. 
 
 B. A cylindrical cover B, the sides of which drop in 
 
 the annular space, about 14 to 16 centimetres 
 high. 
 
 Fig. 52. Thomas and Roos Mutoir. 
 
 The vertical walls of this cover are cut in embrasures at 
 the lower edge, to allow the passage of the must, and rise 
 2 centimetres above the horizontal part, the centre of which 
 carries an escape chimney 3 centimetres in height. 
 
 A second lid or cover C, 4 centimetres in height, with 
 walls perforated with numerous small holes to divide the 
 gases and facilitate the washing. This cover is provided at 
 the upper part with a handle, and inside with a hook E to 
 suspend the sulphur cloths from. This cover extends over 
 the walls of the first cover. The diameter of the cylinder C, 
 
 * This apparatus is constr acted by Vidal. 
 
176 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 should be 1 centimetre greater than that of the cylinder D, 
 and 1 or 2 centimetres less than that of the cylinder B. 
 
 The total depth of the apparatus may vary. We have 
 adopted 50 centimetres, which is sufficient to prevent the 
 must from splashing out, even during rapid filling. 
 
 The following is the method of operating : The appara- 
 tus is placed in the manhole and the upper flange carefully 
 luted. It is then filled with must till it overflows inside 
 over D. The required quantity of sulphur is then suspended 
 to the hook E in the shape of sulphured cloth, or sticks, 
 placed in a suitable recipient. The sulphur is lighted and 
 introduced into the vat through D, the cone C resting over 
 the cylinder D then forming a liquid joint during the com- 
 bustion of the sulphur. The end of the combustion is shown 
 by the cessation of bubbling. The sulphur is then removed, 
 and the pieces B and C placed in position. It only remains 
 then to start filling with must. 
 
 The liquid falls over the cover C, and partly passes 
 through the horizontal perforated parts, filling the liquid 
 joint between D and C. The excess flows over the sides 
 of the cover C, forming a thin sheet conducing to effective 
 washing. It passes into D through the embrasures at the 
 base of B, and falls into the vat in a thin layer, offering a 
 large surface for the absorption of the gases. 
 
 Whatever be the quantity of 
 sulphur burnt in the vat, the absorp- 
 tion of the sulphurous acid is com- 
 plete, for no smell can be detected 
 above the apparatus. The same 
 arrangement may be used for bumj- 
 holes. In this" case the piece A is 
 modified, as shown in Fig. 53. It 
 is prolonged by a conical tube, in 
 the side of which a small tube is 
 placed for the exit of the gas evolved 
 during the filling. 
 
 It goes without saying that in this 
 case, unless the cask be small, the 
 introduction and combustion of the 
 sulphur must be done through the 
 bottom manhole. 
 
 Fig. 53. Arrangement for 
 Bung-hole. 
 
VILIFICATION OF WHITE WINE. 177 
 
 Through the fact that the sulphurous fumes contained in 
 the vessel are completely absorbed by the must, this appara- 
 tus may be considered as a measuring and absorption 
 apparatus. 
 
 We know that when sulphur is burnt it produces double 
 of its weight in gas ; if, therefore, we wish to charge the 
 must with TI grammes of sulphurous acid per hectolitre we 
 
 must burn before filling-- grammes of sulphur, the air con- 
 tained in the vessel is more than sufficient to produce the 
 required quantity of sulphurous acid. 
 
 Under ordinary conditions of temperature air contains at 
 least 20 grammes per hectolitre of oxygen, which can burn 
 20 grammes of sulphur to form 40 grammes of sulphurous 
 anhydride. This quantity is four times greater than that 
 required for perfect debourbage, if completely absorbed by 
 the liquid. 
 
 But during the combustion of the sulphur the gas in the 
 vessel increases in volume through the heat developed by 
 the combustion. It is, therefore, necessary, in order to 
 avoid loss and preserve the exactitude of the measurement 
 and absorption, that the vessel be closed in such a way 
 that the gas can only escape after having yielded the 
 sulphurous acid to the must. 
 
 At M. Thomas' cellar the arrangement of the vats facili- 
 tates the introduction of a cast-iron pot filled with sulphur, 
 which is suspended to the top of the vat at a certain distance 
 from the manhole, in such a position that the must does not 
 touch it. 
 
 The sulphur is lighted, the apparatus immediately placed 
 in position, luted with plaster, and filled with must, taking 
 care to fill up two or three times till the combustion 
 is over. This is easily noticed by the cessation of bubbling, 
 the filling of the vat then begins. 
 
 When it is necessary to deal with a large wooden cask we 
 begin by fixing the apparatus. The sulphur is introduced 
 and lighted at the bottom opening, when the combustion is 
 finished and the equilibrium established for a column of 
 5 millimetres of water, the height of the liquid joint, it is 
 possible without difficulty to open the bottom manhole and 
 
 10649. M 
 
178 WINE-MAKING IN HOT CLIMATES. 
 
 remove the sulphur recipient, and close the opening. If 
 this operation is done quickly the loss of gas is negligible. 
 
 At this moment the difference of pressure between the gas 
 in the vat, and the atmosphere, is sufficiently small to be out 
 of consideration. 
 
 To avoid luting with plaster, F. Crassous, Director of the 
 Compagnie des Salins du Midi, proposed placing under the 
 flange of the apparatus an india-rubber tube, which, when 
 compressed by the weight of the apparatus, will insure an 
 air-tight joint. 
 
 We think that the air chamber of the pneumatic bicycle 
 tire would answer perfectly for this purpose. It could be 
 inflated to the required amount, and the thin rubber they 
 are made of would insure the exact adaptation of the tube 
 to all the irregularities of the wood o.r masonry. We have 
 not yet seen this idea applied in practice, and, therefore, can 
 offer no positive advice about it ; but it would certainly 
 facilitate greatly the handling of the apparatus.* 
 
 To finish the various processes of the application of 
 sulphur, we will describe a method called pump sulphuring. 
 This idea is due to M. Senac, Viticulturist of the Departe- 
 ment of the Gard, which while allowing an exact measure- 
 ment dispenses with the use of special apparatus. 
 
 The principle consists in forcing into the must by means 
 of a pump all the gas produced by the combustion of a 
 given weight of sulphur ; in this particular case the pump 
 not only serves to force the sulphurous fumes into the must, 
 but also acts as a regulator of the introduction of air, in 
 such a way that the combustion of the sulphur is propor- 
 tional to the rate of pumping. 
 
 A 120-gallon cask with the head knocked out makes an 
 excellent sulphur stove, by placing on the ground an iron 
 pot containing the lighted sulphur, and covering the pot with 
 the cask, the lower edge of which is slightly raised to allow 
 the passage of air. The suction tube of the pump is fixed to 
 the bung-hole, the forcing tube being connected with the vat 
 
 * It would be, however, necessary for the rubber tube not to be placed in 
 contact with the iron hoops, and to fit on the wood only. This case is rather 
 exceptional, as the centre hoops pass very close to the top manhole. 
 
VILIFICATION OF WHITE WINE. 
 
 179 
 
 (Fig. 54), the gas resulting from the combustion forced into the 
 vat is completely absorbed by the must, during the operation 
 no sulphurous smell can be detected around the stove, nor at 
 
 Fig. 54. Pump Sulphuring. 
 
 the top hole of the vat. This is an evident proof of the com- 
 plete absorption of the gas and of a rigorous measurement, for 
 it suffices to weigh the sulphur to be burnt. To apply this 
 method to the debourbage of white wine, we begin to force the 
 gas when the vat contains a few hectolitres of must, the filling 
 up and the sulphuring continuing simultaneously, the latter 
 requiring less time than the former. . The pump is stopped 
 as soon as the vat is sufficiently full, and we can then as an 
 extra precaution give a few strokes of the pump to complete 
 the stirring of the mass, and insure the perfect mixing of the 
 sulphured must with that added subsequently. 
 
 FERMENTATION. 
 
 When, after sufficient lapse of time the previously opaque 
 must has become opalescent, the moment has arrived to 
 separate it from the deposit, and to remove it to the vat where 
 fermentation is to take place. 
 
 During this operation the must should be very energetically 
 aerated to allow the last traces of sulphurous acid to be trans- 
 formed by the oxygen of the air, and to enable the oxygen to 
 
 M 2 
 
180 WINE-MAKING IN HOT CLIMATES. 
 
 remain in solution in the must, so as to assist the multiplica- 
 tion of the yeast. When placed in the fermenting vat the 
 white must may be left to itself without any danger, through 
 the debourbage it has been submitted to, the fermentation 
 starts slowly, and is less active than in the case of red wines. 
 
 The time necessary for the complete transformation of the 
 sugar into alcohol is much longer, and one of the consequences 
 of this slow transformation is a much smaller elevation of 
 temperature. 
 
 It is only necessary in rare cases to refrigerate white wines 
 after debourbage, even in the hottest regions of Algeria, for 
 independently of the retarding causes we have already ex- 
 plained, the debourbage has also an advantage in allowing the 
 must to cool down during the two or three days rest in the 
 vat, which is always below the outside temperature. 
 
 As soon as the fermentation is finished, which is shown by 
 the cessation of the evolution of gases, the white wines should 
 be racked and placed in slightly sulphured casks until per- 
 fectlv cleared. 
 
 MANUFACTURE OF WHITE WINE FROM RED GRAPES. 
 
 The only difference resides in the precautions taken to 
 insure the non-dissolution of the colour, it is essential : 
 
 First To avoid incipient fermentation before the separa- 
 tion of the must, carefully avoiding squashing the grapes 
 before they are brought to the crusher, and proceeding rapidly 
 with the operations of crushing and pressing. 
 
 Second To crush the grapes without disintegrating the 
 skins, so as not to liberate the colouring matter contained in 
 their cells. 
 
 Third To destroy as completely as possible the colouring 
 matter which may have been dissolved in the must, and 
 separate by debourbage the fragments of coloured skin in 
 suspension. 
 
 Therefore, to make white wine from red grapes we must 
 lightly crush the grapes, separate the juice by drainage, and 
 then by pressing, reserving the juice to be fermented to red 
 wine as soon as it becomes too strongly coloured, then pro- 
 ceed to the debourbage, and finally leave to ferment. 
 
 This is the process most generally used, but always fur- 
 nishes wine too pink to be called white, and not enough 
 coloured to be called red. 
 
VINDICATION OF WHITE WINE. 181 
 
 It is necessary after fermentation to sulphur strongly 
 several times, to reduce the colour, and it is not possible to 
 make really white wine without altering the character of the 
 taste through the frequent sulphuring. 
 
 To obtain fine white wine from red cepages, such as Aramon 
 for instance, the first condition is not to expect too much. 
 
 We think it is preferable, when it is desired to make 100 
 hectolitres of wine from red grapes, to use for the purpose, a 
 quantity of grapes sufficient to make 150 or 200 hectolitres, 
 the 50 or 100 hectolitres remaining being made into red wine. 
 
 By working in this way we obtain white wine as good as 
 it is possible to make it, considering its origin, and red 
 wine of excellent quality, if we slightly modify in the 
 latter case the method of vinification described in the pre- 
 ceding chapter. We are of opinion that white wine should 
 not alone be made from red grapes, but both, so that we 
 cannot exclusively study the vinification of white wine here, 
 but rather mixed red and white vinification. 
 
 It is evident that, if we take from Aramon vintage a more 
 or less greater proportion of the must it can furnish, the 
 proportion of marc and juice in the remaining part will be 
 very different to what it would have been normally. We 
 should, therefore, apply to the remaining part a method only 
 allowing in a lesser degree, the solution of the substances 
 contained in the marc. By limiting the extraction to 40 per 
 cent, we obtain from Aramon a colourless juice which may 
 furnish a good type of white wine made from red grapes. 
 There is no special rule for the vinification of this must, it is 
 submitted to exactly the same operations as in the vinification 
 of white grapes above described, and the same quantity of 
 sulphur used for the debourbage. 
 
 In the vinification as red wine of the remainder of the 
 juice, not used for making white wine, stemming plays an 
 important part. We have seen already that the unfavorable 
 action of the stalks is due to a greater extent to the physical 
 part played by them in facilitating the penetration of the 
 marc by the must, than to the substances yielded by them to 
 the wine. 
 
 The solvent power of the must may be considered constant, 
 but the quantity of soluble matters it extracts from the 
 marc depends on the surface in contact and the time the con- 
 tact lasts. It is evident that the surfaces in contact will be 
 increased in this case, it is therefore necessary to render the 
 
182 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 marc as impenetrable as 
 possible, and to shorten by 
 half the period of macera- 
 tion. Blaquiere's machine 
 (Fig. 55), constructed for 
 the manufacture of white 
 ? wine from red grapes, 
 ; crushes, drains, and stems 
 J at the same time. It does 
 good work, but in our 
 I opinion the proportion of 
 I must separated is too great . 
 | Probably, by diminishing 
 the length of the drainer so 
 | as to obtain only 40 per 
 cent of white juice, the 
 | results would be better. 
 
 Fermentation starts 
 g very rapidly in marcs in- 
 J completely drained for 
 | white wines, the tempera- 
 g ture rises quickly and 
 | reaches on the second <l;iy 
 jf the limit above which the 
 " yeast works imperfectly. 
 This elevation of tem- 
 g perature is one of the prin- 
 cipal causes of the failures 
 in the manufacture of these 
 wines, the inherent defects 
 of high temperatures are 
 still increased in this case 
 by the greater quantity of 
 
 marc in contact with the must. We cannot therefore 
 expect to obtain red wine with fine colour, and clean taste, 
 if we do not maintain the vat between the limits of tempera- 
 ture shown as most favorable, i.e., 28 to 30 C. 
 
 This method of mixed vinification the only one giving 
 good bright wines up to the present time might be replaced 
 with advantage by that which L. Sernichon,* Director of the 
 (Enological Station of the Aude, studied and perfected last 
 vintage. 
 
 * Li. JSemichon. Revue de Viticulture, 1897. 
 
VINDICATION OF WHITE WINE. 183 
 
 The experiments of Semichon on this subject possess an 
 undeniable importance for the South of France. We will 
 quote in extenso this communication, trusting- it will be 
 applied in practice by the viticulturists of the South. 
 
 NEW METHOD FOR THE VINDICATION OF WHITE WINES. 
 
 " The consumption of white wines has greatly increased 
 in latter years, raising as a consequence the market value 
 of this product. For this reason viticulturists have tried 
 to render practical the manufacture of white wine from 
 red grapes ; in this direction the efforts of all tended to 
 obtain the greatest possible yield of pink must from a 
 given quantity of vintage, but have invariably depended on 
 the old process of manufacture based on decolouration 
 with sulphurous fumes. 
 
 This process, however, is very defective, the enormous 
 difference in the bouquet and flavour between pink and 
 white wines made from the same grapes, already shows 
 that the sulphurous acid deprives the wine of many of its 
 qualities, and leaves a disagreeable taste. It acts as a 
 reducing agent, and decomposes the colouring matters by 
 removal of oxygen. When the wine comes in contact with 
 air through the various manipulations it is submitted to, it 
 absorbs oxygen, the colouring matter re-appears and the 
 wine becomes pink.* 
 
 " If, therefore, the white wine made in this way is truly 
 white and neutral in taste, we may assert that it is in a state 
 of unstable equilibrium, between two situations equally 
 defective, the excess of sulphurous acid which gives it a bad 
 taste, and its inherent defect which renders it pink. 
 
 " These two defects are serious obstacles in commerce, and 
 of such importance that many merchants have given up 
 buying or making white wine from red grapes ; we are 
 almost obliged now to obtain good table wine to have 
 recourse to wines made from white grapes. 
 
 * As far as the unfavorable action of the sulphurous acid is concerned, we 
 do not share the opinion of our colleague, for here, as anywhere else, it is a 
 question of exact measurement of the sulphur used. We have noticed that 
 the sulphurous acid produced by the combustion of sulphured cloth remains 
 more evident in the wine than that produced by the combustion of pure sulphur. 
 This is caused, no doubt, by the formation of sulphuretted bodies, due to the 
 combustion of the organic matter of the cloth. L.R. 
 
184 WINE-MAKING IN HOT CLIMATES. 
 
 " In 1895, Martinand* studied a more rational method for 
 the, decoloration of must, which seems destined to have, 
 in practice, a great future. It consists in oxidizing the 
 colouring matter and precipitating it, instead of simply 
 masking it by reduction. 
 
 " The method of vinification he advocates includes five 
 different phases : 
 
 1. Extraction of the must without taking the colour 
 
 into account. 
 
 2. Cooling below 15 C. to prevent fermentation 
 
 starting. 
 
 3. Aeration of the must and oxidation to precipitate the 
 
 colouring matter. 
 
 4. Filtering under pressure. 
 
 5. Fermentation. 
 
 " This method presents, in practice, many difficulties for 
 instance, the refrigeration to below 15 C., which requires 
 special machines, and is difficult to apply on a large scale: 
 and the filtration under pressure, which is tedious and 
 delicate, requiring expensive apparatus. 
 
 " We have been able to modify this method, so as to 
 render it simpler and more advantageous than the sulphur- 
 ous acid method. It suffices to dispense with refrigeration, 
 and proceed to aerate rapidly by causing the must to fall in 
 a shower in contact with the air, immediately after crushing 
 or pressing. 
 
 " The colour changes to brown, through the oxidation of 
 the colouring matter, which remains suspended in the 
 liquid. 
 
 " The essential point is that the oxidation be sufficient 
 for the colour to remain insoluble, in the mixture of water, 
 alcohol, and acids, constituting the made wine ; the fermen- 
 tation proceeds in the usual way, and when completed, the 
 particles in suspension subside slowly. We may, however, 
 increase the rate of subsidence by a slight fining, for the 
 oxidized colouring matter plays the part of tannin. 
 
 " It is indispensable in Martinand's method to separate 
 the colouring matter before any formation of alcohol, how- 
 ever slight, and that is why he advised the refrigeration of 
 the musts so as to retard the fermentation, and to aerate 
 and filter before it started. 
 
 * Revue de Viticulture, vol. iv., 1895, and Comptes rendus de I' Academic des 
 Sciences, 1895. 
 
VINDICATION OF WHITE WINE. 185 
 
 " Experiments showed us that this is not indispensable, 
 and that it is possible to aerate sufficiently before the pro- 
 duction of alcohol be detectable. 
 
 " And, further, the separation of the oxidized colouring 
 matter is useless. 
 
 " To ascertain the value of this method, we studied it 
 under most favorable conditions, and made the following 
 experiments at the Chateau clu Pech, belonging to Mrs. de 
 Riviere, with the assistance of the manager, Mr. Ritouret. 
 
 "On the 4th September, 1896, we started to fill, in the 
 morning, a 300 hectolitre vat with Aramon vintage. After 
 several hours, the vat being half full, we drew must by the 
 bottom opening, and divided it into three casks. 
 
 "No. 1. A 120-gallon cask, with the head knocked out, 
 through the contents of which air was forced for one hour. 
 
 "No. 2. A 120-gallon cask, strongly sulphured, to make 
 wine by the old process. 
 
 u No. 3. A 120-gallon cask, in which the wine was left to 
 ferment naturally, to make pink wine. 
 
 "The must drawn from the vat had a temperature of 
 18 C, and was decidedly pink in colour. 
 
 " The must, No. 1, after an hour's aeration, became brown 
 coloured, the oxidized colouring matter remained in suspen- 
 sion in the state of fine particles, which pass through any 
 filter ; the next day, 5th of September, it was again aerated 
 for one hour, the brown turbid must was then placed in a 
 new cask and left to ferment. 
 
 " Ten days after No. 1 was still slightly fermenting, turbid, 
 but white with slightly yellowish tint ; it was racked, the 
 colouring matter subsided gradually, and in February the 
 liquid was of a bright yellow colour with a very slight 
 turbidity. 
 
 " No. 2 presented the maximum of decoloration and 
 limpidity on the evening of the filling up ; ten days after it had 
 not started to ferment. By error the sulphur had been used 
 in excess, and we were obliged, in order to make the fer- 
 mentation start, to rack it several times in contact with air ; 
 during this operation the sulphurous anhydride gave by 
 oxidation sulphuric acid, which conduced to the re-appear- 
 ance of the colouring matter ; six weeks after the must was in 
 tumultuous fermentation, and the colour re-appeared; now 
 
186 WINE-MAKING IN HOT CLIMATES. 
 
 in February it still contains unfermented sugar, and is the 
 most strongly coloured of the three. 
 
 " No. 3 was decidedly pink, and still slightly fermenting 
 ten days after ; ten weeks after it was still pink, bright and 
 dry, and retained these characters. 
 
 " The wine made by the aeration process only presents the 
 difficulty of clarification, and we made several experiments 
 on this subject. 
 
 " First The filtration is infinitely easier and more rapid, 
 as might be foreseen, with wine than with must. 
 
 Second The addition of a small quantity of salt, by increas- 
 ing the density of the particles in suspension, favours their 
 subsidence ; but we do not advocate this method, as it affects 
 the taste of the wine. 
 
 " Third A slight fining gives a still better result ; with 10 
 grammes of isinglass per hectolitre we obtained a bright 
 wine of fine yellowish colour. 
 
 " If a few drops of sulphuric or nitric acid be added to the 
 wine before fining, it becomes pink, the colouring matter in 
 suspension being dissolved by the acid ; prolonged action of 
 air never has this result. If the acid is added after fining, 
 the wine retains its yellowish colour, whatever may be the 
 quantity of acid added. 
 
 " It is, therefore, certain that it is the colouring matter in 
 suspension which renders the wine turbid, and that it plays 
 towards the finings the part of tannin, that the bright wine 
 fined or filtered will never become pink again, as wine made 
 by the sulphurous acid process does, for the colouring matter, 
 instead of being simply masked, is completely separated. 
 
 a What degree of aeration is necessary and sufficient ? 
 
 " We determined the influence of prolonged aeration, and 
 obtained the same results as Martinand. We will now show 
 that the aeration of the must in No. 1 was excessive. The fol- 
 lowing are the results of comparisons of the musts of three 
 wines made in the cellar, taken the evening of the filling of 
 the vat, and left in glass flasks to finish fermenting naturally, 
 with five samples of the same must taken the same day from 
 the bottom of the vat and submitted to aeration, varying in 
 duration. The aeration was effected by means of a bellows 
 connected with a glass tube, terminated in a finely-drawn- 
 out point. These samples were afterwards left to ferment 
 naturally. 
 
VILIFICATION OF WHITE WINE. 
 
 187 
 
 " With regard to their colour and classification, they may 
 be placed as follows : 
 
 Description of Sample. 
 
 After One Month. 
 
 After Two Months. 
 
 Wine from No. 2. sul- 
 
 Pink, in conseauence of 
 
 Pink, in conseouenof 
 
 phured 
 
 Duplicate, not aerated 
 Aerated one -quarter of 
 
 an hour 
 Wine from No. 3, pink* 
 
 Aerated for half -an-hour 
 
 Aerated for three-quar- 
 ters of an hour 
 
 Aerated one hour 
 
 Wine from No. 1 (aerated 
 for one hour by pump- 
 ing in a cask) 
 
 excess of sulphuring 
 
 Pink, clear ... 
 Colourless, very turbid 
 
 Colourless, turbid 
 
 Slightly yellow, turbid 
 Slightly more yellow, a 
 
 little less turbid 
 Also as above 
 Yellowish, turbid 
 
 of excess of sul- 
 phuring 
 
 Pink, clear 
 
 Colourless, very turbid 
 
 Colourless, slightly 
 
 turbid 
 
 Flask broken 
 Slightly more yellow, 
 
 almost clear 
 Also as above 
 Also as above 
 
 " These comparisons show that the yellow coloration is 
 due to a more complete oxidation of the must, and the 
 clarification of the wine seems to be more rapid as the 
 aeration is prolonged. 
 
 " The aeration made in the cellar on the evening of the 
 first day was greater than that made in the flask in the 
 laboratory ; by accident the flask No. 3 was broken, and the 
 must through this absorbed more air. This was sufficient 
 to discharge its colour. 
 
 " It would appear, therefore, that in the first experiment 
 in the cellar the aeration was excessive, and that white 
 wines may be made from Aramon by slightly aerating the 
 must with the pump, or by letting it fall in a shower 
 through a perforated plate. 
 
 " It is our intention to try this on a large scale next 
 vintage. 
 
 "It is easy to ascertain if the aeration has been suffi- 
 cient to discharge all pink colour. The following process, 
 which we adopted in the laboratory, should be used : 
 
 " A few cubic centimetres of the must is passed through 
 filtering paper ; when the liquid is nearly all through, 
 a few cubic centimetres of an aqueous solution 
 containing 10 per cent, of alcohol and 1 per cent. 
 
 * The flask broke, and the wine remained in contact with air during one hour. 
 It was then decanted. These operations were sufficient to render it colourless. 
 
188 WINE-MAKING IN HOT CLIMATES. 
 
 tartaric acid is poured into the funnel. If the 
 liquid passing through the filter is pink, the aera- 
 tion is insufficient, and the pumping of air through 
 the vessel must be continued. The solution used 
 has a percentage of alcohol and acid equal to or 
 greater than the wine to be made, so if the colour 
 is not dissolved in this solution it follows that 
 it will not be dissolved in the wine. 
 
 " What is the value of the wines made by this new 
 method ? They do not possess the defects of wines made 
 by the use of sulphurous acid, and after comparing three 
 wines made at Pech, the following results were obtained : 
 "With regard to flavour, the aerated wine (No. 1) is green, 
 nerveux, and fruity ; No. 2 still contains sugar, which pre- 
 vents a fair comparison with the two others. It tastes of 
 sulphur, and has no fruity flavour ; No. 3 is pink, has as 
 much fruity flavour as No. 1, but is not so nerveux. 
 
 " It might be thought that aeration would alter the con- 
 stitution of the wine. We point out, however, that the 
 must does not contain any volatile matters liable to be dis- 
 sipated by the current of air. Here is the result given by 
 analysis of these three wines : 
 
 No. 1. No. 2. No. 3. 
 
 Alcohol, per cent,, in vol. ... 10-1 ... 8-0 ... 10*1 
 
 Total acidity, per litre ... 5-76 ... 6-77 ... 5-34 
 Dry extract ... ... 15-95 ... 57-30 ... 16-90 
 
 Ash ... ... ... 1-75 ... 2-65 .... 2'30 
 
 Reducing sugar ... ... ... 37-39 ... 
 
 " These results show that the alcoholic strength is the 
 same for the white and pink wines, whatever process of 
 manufacture is used. The 37 grammes of sugar in No. 2, 
 which had not yet fermented, would give about 2 degrees of 
 alcohol, which would bring the figure for No. 2 to the same 
 as the others. 
 
 " The total acidity is slightly higher in the aerated wines, 
 but the difference is negligible. The high acidity in No. 2 
 is due to the sulphurous anhydride transformed into sul- 
 phuric acid.* 
 
 u The dry extract of No. 1 is less than that of the pink 
 wine No. 3. This is due to the precipitation of the colouring 
 
 * The difference is such that it does not seem attributable to the sulphurous 
 anhydride only ; for, if this were so, it would have required such a heavy dose 
 that fermentation would have been rendered impossible. L. R. 
 
VINDICATION OF WHITE WINE. 189 
 
 matter through oxidation. On the whole, the composition 
 of wine made by this new process is practically the same 
 as that of the corresponding pink wines. 
 
 " In conclusion, it is to be hoped that this new method of 
 manufacturing white wines will prove advantageous to both 
 wine manufacturers and merchants. 
 
 " 1st. In vineyards where Aramon is in excess, and where 
 the wine obtained from it is deficient in alcohol and colour, it 
 will be possible to transform a portion of the vintage into 
 white wine, and thus get a better return. On the other 
 hand, the Aramon being in smaller proportion in the rest of 
 the vintage the wine will gain in colour. In years of 
 abundant vintage, where the grapes are large and give 
 lighter wine, deficient in dry extract and colour, a part of 
 the must may be drained from the bottom of the fermenting 
 vat and made into white wine. The remainder, fermenting 
 with a greater proportion of marc, will consequently be 
 richer in dry extract and colour. 
 
 " 2nd. The total extraction of the must by pressing, as 
 advocated by Martinand, will dispense with the costly and 
 complicated plant necessary to extract the limited possible 
 quantity of slightly coloured must from red grapes. 
 
 " 3rd. It is probable that this method will be applicable 
 to other red cepages, such as Carignan, Grenache, and 
 Cinsaut, &c., producing wines of higher value ; this will be 
 tried during next vintage. 
 
 " 4th. The trade will obtain white wines of clean taste, 
 and good keeping qualities, able to be used for the same 
 purposes as wines from white grapes, and not presenting the 
 defects of wines made by the use of sulphurous acid." 
 
190 WINE-MAKING IN HOT CLIMATES. 
 
 CHAPTER VI. 
 
 UTILIZATION OF BY-PRODUCTS. 
 
 The by-products of wine manufacture are the marc from 
 the press, the lees, and the tartar. Each of these by-pro- 
 ducts has a definite value, arid bears a certain proportion to 
 the value of the total vintage. 
 
 Marc. 
 
 It is necessary to distinguish between marc from white 
 and red wine. 
 
 The latter is usually utilized in the South of France for 
 the production of piquettes, or the manufacture of spirit ; the 
 alcohol may be obtained by direct distillation or by the 
 distillation of the piquettes. 
 
 Direct distillation is only possible in the case of red marc, 
 and is not usually done by the vineyard proprietor, but by 
 distillers working by contract. 
 
 The alcohol obtained from the distillation of marc is very 
 much in request in the East of France for immediate con- 
 sumption, but is not thought much of in the South. Its 
 value is always less than that of wine-spirit (brandy) ; for 
 this reason we do not advocate direct distillation, as distilla- 
 tion of piquettes gives a much finer product, and are of 
 opinion that in our region the marc should only be used for 
 the manufacture of good piquettes for immediate consump- 
 tion or distillation, as the case may be. 
 
 The object in manufacturing piquette is to obtain in as 
 small a volume as possible the total alcohol remaining in 
 the marc. 
 
UTILIZATION OF BY-PRODUCTS. 191 
 
 Whatever may be thought about it, however well drained 
 the marc may be, it always contains a large proportion of 
 wine. 
 
 Analyses made by Boussingault, Barral, Mares, Degrnlly, 
 Bouffard, &c., show that the pressed and drained marc 
 generally contains 70 per cent, of liquid, or, to be more 
 correct, of volatile matters; in other words, this means that 
 100 kilos, of drained marc contain 70 litres of wine. 
 
 With the new process this figure is decreased, but never 
 falls below 55 to 60 per cent. 
 
 It is therefore absolutely necessary, if we do not extract 
 this wine from the marc, to utilize the alcoholic contents 
 in some way or other ; the only really practical means is in 
 the manufacture of piquette. 
 
 There are actually three methods of doing this, of very 
 unequal practical value, as shown by Prof. Bouffard* : 
 
 1st. Maceration ; 2nd. Sprinkling, or lixiviation ; 3rd. 
 Methodical washing by displacement. 
 
 For these three methods the marc must be disintegrated 
 and rammed into a suitable vessel. 
 
 To apply the maceration method, a certain quantity of 
 water must be added to the rammed marc, and left in contact 
 with it during a few hours ; the water is then racked off, 
 and replaced by a fresh quantity, and so on till the racked- 
 off water does not extract any more wine. 
 
 This is a very defective method, furnishing very weak 
 piquettes ; it does not answer the desideratum contained in 
 the definition given, which is to accumulate in the smallest 
 possible volume the integral quantity of alcohol contained 
 in the marc. 
 
 The second process, sprinkling or lixiviation of the marc, 
 may be either intermittent or continuous, and is widely 
 used in the South of France. 
 
 A vessel filled with rammed marc is provided with an 
 open tap at the bottom, and the upper surface of the 
 marc is sprinkled by means of different devices (like lawn 
 
 * Progres Agricole et Viticole. 
 
192 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 sprinklers) Fig. 55, amongst which we may note the Bourdil 
 hydraulic sprinkler, and Paul's piquette sprayer. 
 
 Fig. 55. Hydraulic Sprinkler. 
 
 The water descending through the mass diffuses with the 
 wine contained in it, carrying away the wine by the tap, 
 yielding piquettes which become weaker as the operation 
 is continued. 
 
 It is necessary in using this method to operate with 
 great care, stopping the operation when the piquette falls 
 below 2 per cent, of alcohol. On -mixing all the fractions 
 a mixture of half the alcoholic strength of the original 
 wine should result. 
 
UTILIZATION OF BY-PRODUCTS. 193 
 
 There is in th$ lixiviation method a serious defect. This 
 is the drawing downwards of an alcoholic liquid of less 
 density than water, which has naturally a greater tendency 
 to rise up. This drawing down is only obtained by estab- 
 lishing a rapid current of water, which is done at the 
 expense of the alcoholic strength. 
 
 The third system methodical washing by displacement 
 is easily done with suitable vessels, and is free from all the 
 above criticisms. It exhausts the marc satisfactorily, and 
 yields from the commencement till almost complete ex- 
 haustion, piquettes nearly as strong as the original wine, or, 
 at any rate, by mixing all the fractions a liquid of average 
 alcoholic strength very near that of the wine results. Figure 
 56 (p. 194) shows diagrammatical ly the arrangement to be 
 adopted. It is easy to fix this up with any vessels or casks, 
 varying in size according to the quantity of vintage to be 
 treated. 
 
 In methodical washing done by displacement we aim more 
 at forcing the wine upwards than at obtaining diffusion ; 
 theoretically the water acts only as a piston, adapting itself 
 to the irregularities of surface, filling all the cavities, and 
 pushing out the liquid, wetting those surfaces or imprisoned 
 in the cavities. 
 
 In practice this does not happen, however, as diffusion 
 takes place ; but, as we have already pointed out in speak- 
 ing of the non-pressed marc, the diffusion zone only forms a 
 layer of a certain thickness, so that we can almost always 
 obtain pure wine ' at the end of the system. The essential 
 point in methodical displacement (per ascensum) that is to 
 say, by means of a rising instead of a descending column of 
 water is to carefully regulate the rate of flow of the water. 
 The ascensional speed should always be slow enough not to 
 drown the marc, as this would simply place the process on 
 the same level -as that of maceration or lixiviation. 
 
 One of the conditions for success depends on the arrange- 
 ment of the marc, which must be well disintegrated and 
 evenly rammed. 
 
 The vats should be provided with false bottoms, under 
 which the water enters. The first vat overflows into the 
 second, the second into the third, and so on. Four vessels 
 are sufficiently efficacious. 
 
 It is easy to explain the good results given by this method. 
 
 10649. N 
 
194 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 CO 
 
 D 
 
UTILIZATION OF BY-PRODUCTS. 195 
 
 Instead of a continuous operation, let us consider the case 
 of an intermittent one, and the four vessels full of marc, from 
 wine giving- 10 per cent, of alcohol. 
 
 If the marc contained 60 per cent, of wine, 100 kilos, 
 would contain 60 litres. Let us wet or submerge the marc 
 with as many times 60 litres of water as there are 100 
 kilos, of marc, and let it remain in contact. The diffusion 
 takes place progressively, and, after a few hours, the 
 vessel will contain for each 100 kilos, of marc 120 litres 
 of liquid, the alcoholic strength of which will be half that 
 of the original wine that is to say, 5 per cent. 
 
 Let us now pass 60 litres of this liquid into the second 
 vessel, also charged with marc containing 60 per cent, of 
 wine ; after contact the mixture will have an alcoholic 
 strength not lying between 10 and 0, but between 10 and 5 
 that is to say, 7*5 per cent. 
 
 Through the same procedure the third vessel charged 
 with the liquid from the second will yield a piquette con- 
 taining 8*75 per cent, of alcohol, and the fourth vessel 
 charged with the liquid from the third will yield a piquette 
 containing 9' 5 per cent. 
 
 In a continuous operation the results are the same, or 
 even better, for in a well-performed operation the liquid over- 
 flowing from the first vessel into the second would already 
 have an alcoholic strength above half that of the wine. 
 
 In practice it is usual to stop washing the first vat when 
 the liquid overflowing into the second has become poor in 
 colour, and contains 1J to 1 per cent, of alcohol. In a 
 successful operation the alcoholic strength falls rapidly. 
 In a few minutes to one hour, according to the size of the 
 vessel, the piquettes fall from 5 or 6 per cent, to 1 per cent. 
 The water delivery should then be directed into the second 
 vessel, the first being disconnected, emptied, and recharged 
 with fresh marc, and connected to the opposite end of the 
 system. 
 
 It is, therefore, the methodical washing by displacement 
 which seems to be most recommendable. We think it is the 
 only method enabling rich piquettes to be obtained, of good 
 keeping qualities, and also more easily and economically 
 distilled. The alcohol obtained by distillation of well and 
 soundly made piquettes has none of the defects of that 
 extracted from the marc direct ; on the contrary, it possesses 
 all the qualities which give wine-spirit a higher value. 
 
196 WINE-MAKIXG IN HOT CLIMATES. 
 
 With regard to niarc from white wines, we must operate 
 differently ; the problem here is reversed, for it is must, a 
 liquid denser than water, that has to be extracted from the 
 marc. 
 
 Sometimes the white marc is left to ferment as it comes 
 out of the press, and is later on converted into piquette, or 
 distilled directly ; in both cases the result is very unsatis- 
 factory, the fermentations taking place in pressed marc are 
 always bad. The piquettes obtained from it are execrable 
 and cannot be used for consumption, and the alcohol result- 
 ing from their distillation does not repay the cost of 
 production. 
 
 The direct distillation of fermented white marc does not 
 give better results. 
 
 It is therefore necessary to treat the marc directly it 
 leaves the press, to accumulate its sugar contents in water, 
 and leave the saccharine solution to ferment, distilling it 
 ultimately. 
 
 The operations are performed in the same vessels as in 
 the case of red marc, but in this instance we must use the 
 lixiviation method, spraying over the second vessel the 
 liquid gathered from the first, and so on. 
 
 The leaching of the first vat is stopped when the liquid 
 leaving it does not taste sweet. 
 
 It is imperative in this operation to act quickly, to avoid, 
 as far as possible, too active fermentation in the mass. 
 
 As in the case of the treatment of red marc, the exhausted 
 vessels are emptied, charged again, and placed at the other 
 end of the system, while the second vessel becomes in its 
 turn the first. The marc exhausted in the manufacture of 
 piquette cannot yield anything more, but constitutes a good 
 food for cattle, and if not used for that purpose may be used 
 for manure. 
 
 The preservation of washed marc for cattle food is more 
 difficult than that of marc simply taken from the press, for, 
 in the latter case, the wine or alcohol it contains protects it 
 in a certain measure against alterations. 
 
 It is necessary to take more care for the preservation of 
 washed marc. 
 
 The best method consists in stratifying the marc with 
 salt in the proportion of 2 to 3 per cent, in vats or silos 
 compressed tightly, which is easily done by placing a lid 
 weighted with full hogsheads on top, at the rate of 500 
 
UTILIZATION OF BY-PKODUCTS. 197 
 
 kilos, per square metre of surface. Under this small but 
 continuous pressure the height diminishes considerably, 
 and a great quantity of water escapes from the bottom of 
 the vat or silo, the mass becomes very compact, and only 
 the first few centimetres become affected by fungi. 
 
 The marc from white wines may be treated in a similar 
 manner, the residues from the distillation of pique tte con- 
 tain a great quantity of tartar, but we cannot think of 
 extracting it. It has, however, a fertilizing value on account 
 of the potash it contains, and should be thrown in the 
 manure pit. It is indispensable to mix it with manure, for 
 in the state it leaves the still it cannot be applied directly 
 to the soil, as it would destroy the roots and kill the plants 
 with which it came in contact, unless used in small quantity 
 or treated with lime to first neutralize the acids. 
 
 The direct distillation of marc assures the recovery of 
 an important part of the tartar it contains, but this slight 
 advantage does not counterbalance the other imperfections 
 of the method. 
 
 Lees and Tartar. The lees deposited by both red and 
 white wines, during the time which elapses between the 
 fermentation and the second racking, have considerable 
 value, on account of the bitartrate of potash they contain. 
 The lees from the debourbage (sedimentation) of white wines 
 are only fit for manure. 
 
 The lees should be treated to extract the wine they 
 contain before being sold for tartar. 
 
 However thick they may be, they contain, when leaving 
 the cask or vat, more than 75 per cent, of their weight of 
 wine. The simplest method to extract the wine consists in 
 filling strong cloth bags with the lees, piling them in the press, 
 and submitting them to slight but continuous pressure. 
 
 The wines gathered in this manner are not of much value, 
 but may be used for the still. However, submitted to 
 judicious treatment they improve, and may be used for 
 consumption. 
 
 The pressed lees should be treated for their tartar by the 
 wine-maker. This is a simple and remunerative operation, 
 for the tartar obtained has always a higher value than that 
 of the lees, and what is more, we retain in addition the 
 residues from the treatment, which are first-class for manur- 
 ing purposes. The value of tartar per unit is always less in 
 the lees than in cream of tartar. 
 
198 WINK-MAKING IN HOT CLIMATES. 
 
 Good lees in a dry state do not contain much more than 
 25 per cent, of tartar, and the 25 kilos, of tartar is the only 
 substance paid for by the buyer when fixing the price of 100 
 kilos. The remaining 75 kilos, contain about 4 per cent, of 
 nitrogen, which at the market price of 1'50 fr. per unit brings 
 the value of the 75 kilos, to 4-50 fr. per unit. 
 
 The wine-maker should, therefore, try and extract the 
 tartar from the lees for two reasons first, because the tartar 
 easily obtained at 80 per cent, strength can be sold at 
 1*40 fr. per unit, while only 1 fr. or I'lO fr. would be paid for 
 the tartar in the lees. Secondly, because it retains on the 
 property an excellent manure, which costs nothing. 
 
 It goes without saying, that it is not necessary to treat 
 the lees every year. ' One may, after drying, store it, and 
 treat it every other year according to the quantity. 
 
 The extraction of tartar from lees is very simple. It only 
 requires a large boiler and casks. 
 
 The strength of the lees being known (we will see later on 
 how it is ascertained), it is boiled with water, placing such 
 a quantity of lees in the water as will represent about 7 kilos, 
 of pure tartar per hectolitre of water. 
 
 With lees of 25 per cent., about 30 kilos, of lees should, 
 therefore, be added to one hectolitre of water. 
 
 After a quarter of an hour's boiling, during which the 
 mass is stirred, allow it to deposit for a few minutes ; the 
 liquid is then passed through a piece of canvas stretched 
 over a tub, and the operation started again; on cooling 
 the water previously boiled with the lees, almost the whole 
 of the tartar in solution is deposited. Each hectolitre of 
 water used should yield about 6'5 kilos, of tartar, while 
 a half kilo, remains dissolved, but is not lost, for the same 
 water may be used again four or five times. 
 
 If used a greater number of times it becomes rather 
 viscous, preventing the rapid deposition of the tartar. It 
 should, therefore, be renewed after four or five treatments. 
 
 The residues remaining on the canvas, and the water, are 
 sent to the manure pit. 
 
 We can, even without much trouble, dispense with the fil- 
 tration through canvas, and replace it by simple decan- 
 tation ; in this case the boiling must be stopped, the liquid 
 allowed to remain undisturbed for ten minutes or a quarter of 
 an hour, then racked and placed in the depositing vessel. 
 The residue is then removed from the boiler and sent to 
 the manure pit, or kept dry till required. 
 
UTILIZATION OF BY-PRODUCTS. 199 
 
 At the actual market value of tartar* 1-25 fr. per degree in 
 cream of tartar, and 90 centimes in the lees. 1,000 kilos, 
 of lees at 25 per per cent, would give by this treatment, 
 deducting the possible loss: 
 
 225 kilos, of tartar, at 1-25 fr. ... ... 281-25 fr. 
 
 775 kilos, residue for manure, at 4-50 fr. 
 
 per 100 kilos. ... ... ... 34*85 fr. 
 
 Total 316-10 fr. 
 
 While the direct sale of the lees would only bring- in 
 225 fr. 
 
 It is necessary to treat 1,000 kilos, of lees, to boil about 
 35 hectolitres of water, the fuel used for this operation 
 represents a sum much smaller than the credit difference. 
 The labour itself does not add greatly to the expenses, 
 and the work may be done during bad weather, when the men 
 cannot attend to the ordinary out-door work. The figures 
 quoted are exact, assuming that the lees are paid for on 
 the real percentage of tartar, but this is almost never 
 done; more often than not the lees are sold without pre- 
 viously determining their strength, and are in fact fre- 
 quently sold for almost nothing before the wine they 
 contain has been separated, that is to say, in the form of 
 a thick liquid containing 75 per cent, of 'wine. In this 
 method of doing business everything is in favour of the 
 buyer.f 
 
 The tartar obtained from the crust deposited in the casks 
 cannot be submitted to any treatment by the wine-maker, as 
 the increased value it would acquire by refining would not 
 compensate for the extra cost involved. As for the complete 
 refining, it is an operation which only pays on a very large 
 scale. 
 
 The tartar deposited as a crust in the vats, and that 
 extracted from the lees, should, therefore, only be sold on the 
 percentage of bitartrate of potash contained ; but it is 
 necessary for the wine-maker, who cannot wait for the 
 
 * July, 1897. 
 
 tThe boilers used for the destruction of the pyrale (caterpillar) on the 
 stumps of vines may be used to furnish the boiling water for the treatment of 
 the lees. In this case a simple cask may be used for the dissolution of the tar- 
 tar, taking care, however, to charge the water with a little less lees on account of 
 the difference of temperature, which will always be less if the water is removed 
 from the boiler. 
 
200 WINE-MAKING IN HOT CLIMATES. 
 
 result of a laboratory assay or accept that given by the 
 buyer, to ascertain, at least approximately, the value of the 
 tartar to be sold. 
 
 Determination of the percentage of bitartrate of potash in 
 the crust or lees. 
 
 F. Chabert, Analyst at the (Enological Station of the 
 Herault, has tried to realize the conditions under which 
 the acidimetric method generally used in laboratories may be 
 placed in the hands of persons not accustomed to chemical 
 manipulations ; and, in order not to increase the laboratory 
 outfit of the cellar, to use for this purpose the apparatus 
 generally employed for measuring the acidity of the must. 
 
 We require, as in the case of the acidimetre, 
 
 A burette graduated in tenths of a cubic centimetre. 
 
 A titrated alkaline solution of potash or soda. 
 
 A glass flask of one litre capacity. 
 
 An alcoholic solution of phenolphthalein. 
 
 Litmus paper. 
 
 Such is the material necessary for testing the tartar. 
 
 A thorough sampling is the first condition necessary for a 
 reliable analysis. 
 
 If the tartar is contained in bags or placed in heaps, a 
 handful is taken from different parts of every bag or heap. 
 These are placed together, and will form a sample varying 
 in size according to the bulk of the stock. This first 
 sample should then be thoroughly crushed, well mixed, and 
 divided into two parts. One-half is then replaced in the 
 bags, the other half being re-submitted to the halving 
 operation, and so on until a perfectly homogeneous mixture 
 is obtained. An average sample is then drawn off, of four 
 or five hundred grammes, which is powdered in a mortar, 
 and serves for the analysis. 
 
 Analysts usually operate on very small quantities, but it 
 is better for persons not conversant with operations of this 
 class to work on a rather large weight the possible errors 
 are then only multiplied by a small figure, and do not 
 notably influence the results calculated to 100. 
 
 By working on 5 grammes of tartar, fair accuracy is 
 obtained. The indispensable weighing is a delicate part of 
 the work, for it must be done with a balance turning to 1 or 
 2 centigrammes, and such balances are not often found in 
 cellars. 
 
UTILIZATION OF BY-PRODUCTS. 201 
 
 Any pharmacist or chemist can perform the weighing ; 
 but we think that sufficient use might be found for a small 
 balance to justify its purchase. The price, however, is a 
 trifle, and does not exceed 20 francs (16s. 6d.). 
 
 The 5 grammes of tartar or lees are placed in the glass 
 flask, 300 to 400 cubic centimetres of distilled water 
 added, and the contents boiled. Four or five minutes' boiling 
 is sufficient to insure the complete solution of the cream of 
 tartar. An insoluble residue always remains, of varying quan- 
 tity, according as the operation is made on lees or crust. It is 
 not necessary to decant, for in this case we should be obliged to 
 wash the residue two or three times with 50 cubic centimetres 
 of boiling water. It is on the solution of tartar and in the flask 
 itself that the determination is made. Add to the solution, 
 after boiling, four or five drops of phenolphthalein, then while 
 constantly agitating the contents of the flask add the 
 alkaline solution from the burette till the red colour appears 
 and indicates the end of the operation the change of colour 
 is readily detected after a few trials. With white tartars it 
 is so decisive that one drop in excess of the alkaline solution 
 is sufficient to cause the appearance of the colour. Its 
 detection when working on red tartars is not so easy ; but' 
 we may use a much surer although rather more tedious 
 method, that is, by testing from time to time with litmus 
 paper. 
 
 When the end of the reaction is almost reached the mix- 
 ture becomes bronze coloured. The appearance of this 
 colour is an indication that the reaction is almost finished. 
 If from this moment, after each two or three drops of the 
 alkaline solution added, we remove a drop of the mixture by 
 means of a stirring rod and place it on a strip of litmus 
 paper, the paper will change colour and finally become 
 pure blue, instead of the red colour it had in the pre- 
 ceding case. This change of colour indicates the end of 
 the operation. The analysis is now finished, and it only 
 remains to translate the figures obtained into definite 
 results. 
 
 To arrive at the change of colour of the liquid, we used 
 a certain volume of alkaline solution, as determined by the 
 reading of the burette. .Let us suppose that the burette, 
 filled to zero with the alkaline solution, reads at the end of 
 the operation 15-6 c.c. This means that 15'6 c.c. were used 
 
202 WINE-MAKING IN HOT CLIMATES. 
 
 to neutralize the acidity of the tartar ; this acidity is propor- 
 tional to its content in tartar. It suffices, therefore, to know 
 to what acidity 1 c.c. of the alkaline liquor corresponds, in 
 order to ascertain by a very easy calculation the richness in 
 tartar. Let us suppose, to make this quite clear, an alkaline 
 liquor in which each cubic centimetre corresponds to 0-10 
 gramme of tartaric acid, the ratio between tartaric acid and 
 cream of tartar is 2*506, which means that 1 of tartaric 
 acid corresponds to 2*506 of cream of tartar. The alkaline 
 liquor will, therefore, in this case be equivalent to 0-2506 
 per 1 c.c. used. 
 
 Therefore, as we have used for 5 grammes of the solution 
 of tartar, 15*6 c.c. of the alkaline liquor, the 5 grammes 
 contained 
 
 0.2506x15*6 = 3*909 gr. 
 and, therefore, 100 grammes would contain 
 
 3.909x20=78*18 gr. 
 
 In this particular case the strength of the tartar is 78*18 
 per cent. 
 
 It is not indispensable for the alkaline liquor to be of 
 the strength above mentioned. It may be of any strength, 
 but if too weak, it becomes necessary to use large quan- 
 tities and unnecessarily prolong the operation. If, on the 
 contrary, the liquor is too strong, too small a volume is 
 used, and the slightest error in reading the volume de- 
 livered would be an appreciable factor in the quantities 
 used. If, for instance, in the above case we had used a 
 liquor four times stronger, an error of reading of 0*1 c.c. 
 would have caused an error of 2 per cent, in the final result, 
 while, with the solution adopted above, the same error of 
 reading would only cause a final error of 0*5 per cent. 
 
 The figure of 0*10 gr. of tartaric acid per c.c. used in the 
 above example, allows a sufficiently close approximation, and 
 we think it is well not to exceed it. The most convenient 
 limits for the strength of the alkaline liquor correspond to 
 from 0-05 to 0*10 of tartaric acid .per c.c., if the alkaline solu- 
 tion varies between these limits it may be safely used. It 
 will suffice in any case to multiply the known strength 
 equivalent to tartaric acid, by the ratio 2*506 to obtain its 
 equivalent in tartar. 
 
UTILIZATION OF BY-PKODUCTS. 203 
 
 If, as often happens, the strength of the alkaline liquor 
 is only known expressed as sulphuric acid, it may be con- 
 verted to tartaric acid by multiplying by 1*53, and into 
 bitartrate of potash by multiplying the result of the last 
 multiplication by 2*506. 
 
 Example. Take for example the alkaline liquor known 
 as normal, very frequently used by analysts, and which may 
 be easily purchased from any chemical laboratory, its 
 strength is 0*049 in sulphuric acid per cubic centimetre, that 
 is to say, that 1 cubic centimetre neutralizes 0*049 of sul- 
 phuric acid, its equivalent in bitartrate of potash is from 
 what we have seen above 0*049 x 1*53 x 2*506 = 0*188 of bitar- 
 trate of potash. If 20*6 c.c. of this liquor were required to 
 bring about the change of colour in a boiling solution of 
 5 grammes of crude tartar, it means that the sample con- 
 tains in 5 grammes 0*188 gr. x20*6 c.c. = 3*87 gr. 
 and for 100 gr. 3*87 gr. x20 c.c. = 77*4 per cent. 
 
 It is evident from the above that the testing is a simple 
 operation. We may even use the alkaline liquor used for 
 the determination of the acidity of the must, for, excepting 
 the weighing and solution of the tartar, the operation is 
 similar in every respect. All those accustomed to the mea- 
 surement of the acidity of must will be able to perform this 
 operation, with exactitude without further teaching. 
 
 It is understood that we only determine by this method 
 the bitartrate of potash present, and not the bitartrate of 
 lime, but this is of no importance. The value is always 
 based on the contents of bitartrate of potash. 
 
 We urge upon wine-makers, who usually sell their tartar 
 without any previous examination, to use the process above 
 described, that is, if they do not wish to send the sample 
 to a laboratory. They will very soon see the advantage 
 resulting from the exact knowledge of the value of the goods 
 placed on the market. Through the sale of the tartar, and 
 by the use of the residues from the lees as manure, the 
 wine-grower will every year make a net profit of 40 centimes 
 per hectolitre of wine produced. 
 
 If tartaric acid has been used for the vinification the 
 figure must be increased. This increase will recuperate a 
 great part of the expense entailed in the purchase of tartaric 
 acid. 
 
204 WINE- MAKING IN HOT CLIMATES. 
 
 CHAPTER VII. 
 
 CARE TO BE GIVEN TO WINE. DEFECTS AND 
 DISEASES. 
 
 Normally constituted wine only requires packings made at 
 opportune times, filling up the casks as often as considered 
 necessary, in order to acquire perfect brightness and be pre- 
 served against the germs which always exist in every 
 vintage. 
 
 The number of rackings to which wine must be submitted^ 
 cannot be fixed a priori, neither can the way in which the 
 rackings should be done, that is, either with or without con- 
 tact with air. This depends on the constitution and future 
 destiny of the wine ; the rackings should be numerous, and 
 the aeration more or less intense according to the rapidity 
 with which we desire to mature the wine. 
 
 Racking is simply a kind of decantation or separation of 
 the clear wine from the subsided lees. 
 
 The first racking, which should be done a fortnight after 
 the de-vatting, separates the wine from a great quantity of 
 solid matters (yeast cells, vegetable particles in suspension, 
 various micro-organisms), but it does not usually furnish 
 bright wine. 
 
 This is due to the wine being saturated with carbonic acid 
 gas which is only slowly liberated. The fine bubbles during 
 their disengagement keep the light particles of lees in sus- 
 pension in the liquid. Frequently, where we have to deal 
 with musts rich in sugar, and which still retain a small 
 quantity of it after fermenting, a slow after fermentation 
 continues during several weeks in the racked wine in such a 
 way that the wine, always bright just after de-vatting, be- 
 comes turbid again in a few days. 
 
 The cold during the winter completely paralyses the work 
 of the different ferments, and induces rapid sedimentation, 
 and consequently rapid clearing of the wine. 
 
 It is therefore when the wine, after the more or less pro- 
 longed action of cold, has acquired complete brightness, that 
 the second racking should be done. 
 
CARE TO BE GIVEN TO WINE. DEFECTS, ETC. 205 
 
 In the South of France this generally corresponds to the 
 middle of January.* If the wines still remain turbid it 
 means that they are defective, and they will then have to 
 be submitted to operations or manipulations somewhat more 
 complex than simple racking. 
 
 The selection of the day on which to perform the racking 
 is not a matter of indifference. We should, on the contrary, 
 always select a day when the barometer is high. There is a 
 saying, in the South of France, that wine should always be 
 racked or bottled when the mistral wind is blowing. This 
 custom is very judicious, because when the mistral is blow- 
 ing, the atmospheric pressure is always high. 
 
 Wine always contains carbonic acid gas in solution, al- 
 though a large quantity is liberated at the first racking ; 
 long after the wine is found almost saturated with it, because 
 the lees disengage it slowly but constantly. 
 
 The solubility of gases in liquids is so much the greater 
 as the pressure is higher, the temperature being equal, so 
 that, if wine saturated with carbonic acid gas remains com- 
 pletely still and clear on a fine day, when the atmospheric 
 pressure is high, it is not so when the weather is unsettled, 
 corresponding to a low pressure, on such days we will ob- 
 serve a more or less rapid disengagement of gas, which does 
 not take place without causing the liquid to become turbid. 
 
 We should therefore not only choose a fine day for racking, 
 but, to do it under still better conditions, choose a bright day 
 preceded by several fine days. 
 
 The wine, usually perfectly bright after the racking, almost 
 always becomes slightly turbid a few days after. This is 
 due to the fact that several solid matters only exist in 
 solution in the wine in the presence of carbonic acid gas ; 
 and that the oxygen, when the racking is made in presence 
 of the air, renders some of the matters in solution in the 
 wine insoluble, however, the result aimed at by the racking, 
 that is to say, the separation from yeast cells, is attained. 
 The subsidence of the solid matters taking place in the 
 wine after the racking occurs very quickly, and the lees re- 
 sulting are not detrimental. 
 
 It goes without saying that racked wine should be placed 
 in thoroughly cleansed casks, rendered wholesome by 
 sulphuring. The cask should be left open for a few hours 
 
 * In Victoria, in the Northern districts about the end of June; in the 
 Southern districts, June to July (Trans.). 
 
206 WINE-MAKING IN HOT CLIMATES. 
 
 before filling, to allow the sulphurous acid to escape ; this 
 operation is necessary, for sulphuring, when done to render 
 the cask wholesome, must be 4one so heavily that it would 
 be detrimental to the wine if it were allowed to absorb it. 
 However, if we should not introduce into the wine a large 
 quantity of sulphurous acid, it does not mean that we should 
 not sulphur at all. 
 
 Sulphur always exerts a favorable action on both white 
 and red wines, in spite of the opinions to the contrary with 
 regard to the latter. 
 
 Although it is necessary to sweep out the sulphur fumes 
 by a good, draught before filling, we think it will always 
 prove of advantage to burn, before filling, a small quantity 
 of sulphur, which may be fixed at 1. gramme per hectolitre. 
 
 Treated in this way, the wines of the South of France are 
 sufficiently armed to enable them to pull through the 
 summer, the casks only require to be kept completely filled. 
 
 Whenever wine is not perfectly clear and bright after the 
 January racking (in Victoria about June), it means that it 
 is diseased. The disease must then be treated at once by 
 proper methods, to enable the wine to become bright and 
 clear. 
 
 DEFECTS AND DISEASES OF WINE. 
 
 It is necessary to distinguish between defective and 
 diseased wine. 
 
 A modification in the taste and physical aspect of wine 
 constitutes a defect, but not a disease. The defects, especially 
 those of taste, have a tendency to become attenuated by 
 maturing. In any case, they do not get worse, while the 
 modifications due to diseases, almost undetectable to the 
 senses at first, increase to the extent of completely altering 
 the constitution of the liquid and render it undrinkable, it 
 an energetic treatment does not arrest the further progress 
 of the evil. 
 
 Wines are all the more liable to contract defects or 
 diseases, as the vintage is less healthy, the vinification less 
 carefully conducted, and the cellar material less thoroughly 
 cleansed and looked after. 
 
 In this, as in any other case, it is better to foresee the 
 disease than to have to cure it. The absolute cleanliness of 
 the cellar material, vessels, crushers, presses, pumps, hoses, 
 
CARE TO BE GIVEN TO WINE. DEFECTS, ETC. 207 
 
 and even the cellar and its surroundings, will avoid a great 
 many of the defects and diseases of wines, and to a greater 
 extent than one might really think. A proper method of 
 vinification will do the rest. The sight, smell, and taste, 
 are all called upon to form an opinion of the wine. 
 
 The tasse (Fig. 38) is a marvellous little instrument for 
 observing wine, the play of light in it is an admirable help. 
 
 The smell enables us to detect certain defects which, not 
 interfering with the colour, would pass unnoticed by the eye. 
 
 The degustation or tasting, performed with care, completes 
 the impressions upon which are based a judgment of the 
 wine. 
 
 The whole mouth, tongue, palate, and even the throat, 
 serve to define the indications of the smell. By drawing back 
 the liquid in the rear of the mouth with a movement 
 similar to that of deglutition, we sometimes notice in an 
 exaggerated or increased manner characters previously 
 detected by the smell, and may thus more exactly determine 
 their nature and intensity. 
 
 A yellowish colour is a frequent defect, and is independent 
 of the cellar material. It is generally due to the abuse of 
 racking during the course of fermentation. 
 
 We know that a great quantity of air is necessary to the 
 must before the start of the fermentations, but when it has 
 once started a small quantity only is necessary. 
 
 The practice of pumping over the head, excellent in so 
 far as it gives more body to the wine, is often a cause of the 
 yellow colour, because it is almost always done in presence 
 of air, with wines always too hot. Hence the yellow colour 
 of hastily-matured wine, which depreciates its commercial 
 value. 
 
 The pumping over the head during fermentation is often 
 useful when the aeration is only necessary for a languishing 
 fermentation, and when the yeast requires invigorating. 
 The yellow colour will be avoided if care be taken not to 
 aerate excessively. 
 
 When the harm is done there is no other remedy but 
 blending with other wines of finer colour and appearance. 
 
 When the wine becomes of a bluish-red, more or less 
 blackish colour, it is a sign of a true defect in constitution. 
 
 Insufficient acidity in the vintage furnishes such dull wine, 
 known as leaden, but the same shades of colour are found in 
 almost all wines attacked by diseases due to microbes. 
 
208 WINK-MAKING IN HOT CLIMATES. 
 
 We have shown two ways of guarding the vintage against 
 deficiency of acidity, the use of the second crop, and tartaric 
 acid. 
 
 In vintaging early the resulting wine will always be acid 
 enough. The first wines made are never leaden ; it is therefore 
 necessary, when vintaging at normal maturity, to increase 
 the percentage of acidity by the addition of tartaric acid. 
 
 The last wines obtained from acidified vintage are as 
 bright, fruity, and nerveux as the first made, while they are 
 more alcoholic. 
 
 For a made wine the remedy is still tartaric acid, provided 
 the leaden appearance is due to a deficiency of acidity, and is 
 not the first symptom of a serious disease. The leaden 
 wines resulting from a deficiency of acidity do not present 
 any peculiarity to the smell, which is not ordinarily the case 
 with diseased wines, but they show to the taste more 
 flabbiness, flatness, and rapidly lose their vinosity when 
 mixed with water. The acidification by addition of tartaric 
 acid is a lawful and efficacious means of remedying this 
 defect, but the action of the remedy is incomparably more 
 satisfactory when applied as a preveutative, that is to say, 
 before the fermentation. 
 
 To ameliorate this class of wines$ we should proceed by 
 preliminary trials, on a quantity, to which tartaric acid is 
 added in fractions of one decigramme, until the eye and 
 the taste are satisfied with the operation. As a result, we 
 will soon arrive at the amount necessary to be added to the 
 wine, which usually lies between 50 and 100 grammes per 
 hectolitre. 
 
 An earthy taste or flavour is also a very frequent defect. 
 This is detected by the smell and taste, and is rather difficult 
 to define exactly. The name is of no assistance, for it leads 
 us to suppose that the defect is due to the soil the wine 
 originates from. This has always been the popular belief ; 
 it simply means that we have been mistaken for a long 
 while. 
 
 " Of all the earthy tastes/' writes an author, u the most 
 peculiar are those which are met with in Algerian wines 
 derived from newly-trenched land, which had, before, borne 
 Pistacia lentiscus, Jujube, dwarf Jackal Palm (Chamasrops 
 humilis), &c. Such soil exhales fantastic odours, which 
 are found again in the wine grown on it, not only smelling, 
 but also tasting." 
 
CABE TO BE GIVEN TO WINE. DEFECTS, ETC. 209 
 
 We do not believe much in the influence of newly-trenched 
 soil, for the very simple reason that when the vine arrives 
 at the productive state the soil is not newly-trenched, and 
 has had time to get rid of all flavours that might have con- 
 taminated it. 
 
 Five or six years ago, wines with an earthy taste were the 
 fashion in Algeria, and that whether they proceeded from 
 old or young vines, from vines planted in ground cleared a 
 great number of years before, or from newly-trenched ground. 
 The wines produced from old ground had that defect even 
 in a more accentuated degree, because they were more 
 alcoholic. 
 
 This is not so any longer. Certain vineyards which during 
 the last twenty years produced wines having an earthy 
 taste, now make clean-tasting wines, and this is simply due 
 to the improved processes and methods of vinifaation. 
 Formerly, the crushed vintage was left to itself, and allowed 
 to ferment in a happy-go-lucky way, only de-vatting when 
 the wine seemed to contain no more sugar, which usually 
 happened fifteen or eighteen days after the fermentation 
 started. It is entirely to this prolonged maceration, taking 
 place at an excessive temperature, that we must attribute 
 the origin of the earthy taste, and not to the earth itself. 
 Since the application of the system of refrigerating musts, 
 which enables regular and short fermentations to be made, 
 the earthy taste due to newly-trenched ground has dis- 
 appeared. 
 
 In the South of France, the same causes produce the same 
 effects, but only to a slight extent. The means of avoiding 
 the earthy taste are very simple, only ferment for five or six 
 days, and prevent the heating of the vat. If there are no 
 means at disposal for cooling, and the vat becomes too hot, 
 de-vat as soon as possible, even at the expense of the colour, 
 for we believe that it is better to make wine of clean taste, 
 and free from earthy taste, than wine rich in colour, and 
 possessing an earthy taste. 
 
 The remedy for the evil is almost useless. It consists 
 in repeated rackings and heavy finings, which only result in 
 attenuating the evil, without causing it to disappear, and in 
 turn exhausting the wine ; the practice of blending is better 
 than anything else. 
 
 Wines sometimes develop a putrid smell, similar to that 
 of sulphuretted hydrogen, caused by the presence of a very 
 
 10649. O 
 
210 WINE-MAKING IN HOT CLIMATES. 
 
 small quantity of sulphur remaining from the sulphuring 
 during the summer, or, to the condition of the vat in which 
 the fermentation was conducted. In the first case it is due to 
 sulphuretted hydrogen, in the second case it is the result of 
 more complex sulphuretted compounds, and then the defect is 
 more tenacious. A very frequent cause of the putrid smell is 
 the use of compounds for luting the vats, into the composition 
 of which blood enters. The blood is generally thought to be 
 more effective when putrefied. It is needless to state that 
 this idea is without foundation. The sulphuretted taste is 
 difficult to remove from the wine. We may, however, arrive 
 at it by strongly sulphuring again, that is to say, by making 
 the wine absorb sulphurous anhydride*, although it seems 
 incredible at first. In reality the sulphuretted hydrogen is 
 destroyed by the sulphurous anhydride, and the wine con- 
 tracts the smell of the latter, which is very different from 
 the former, and possesses the advantage of disappearing in 
 time. 
 
 To remove all other abnormal tastes, such as cask or 
 mouldy taste, the use of olive oil is generally advocated. 
 
 The wine is roused with 1 per cent, of olive oil which 
 suffices to fix to its benefit, or to be more precise, to its 
 detriment, the foreign taste contaminating the wine. 
 
 We think it is only a second-rate method, the success of 
 which is never complete. The olive oil used must be of the 
 very best quality, which renders the method very expensive, 
 anyhow, whatever be the quality of the oil used, the treat- 
 ment always leaves in the wine, side by side with the more or 
 less attenuated initial defect, a disagreeable oily character. 
 
 Mustard powder used in a quantity of 30 or 40 grammes 
 per hectolitre, and stirred with the wine, gave us results, 
 which, without being good, are, however, preferable to those 
 obtained with oil, we may sometimes succeed in rendering by 
 this treatment, the consumption of wine possible, which was 
 otherwise undrinkable. 
 
 We have so far spoken of defects which do not lead to a 
 gradual alteration of the wine. W^e will now describe the 
 principal diseases which completely transform the wine if 
 their evolution is complete. 
 
 They are almost always the result of infinitely small 
 organisms known as microbes, which play such an important 
 
 * This reaction proceeds according to the equation 
 2H 2 S + SO 2 = 2H 2 O + 2 S. (Trans.) 
 
PLATE III. 
 
 Disease known as Flower, Mycoderma, vini. 
 
 Vinegar Disease, MycoAenna aceti. 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 211 
 
 part in our life, although they are so small, and the role of 
 which, unsuspected previous to Pasteur's classical researches, 
 now becomes more apparent every day. 
 
 In oenology their importance is considerable. We know 
 that they are the cause of the genesis of wine, that the mar- 
 vellous transformation of sugar into a'lcohol is due to microbes, 
 but these are salutary microbes. We are going to study now 
 other microbes of noxious character, causing the destruction 
 of the work of the first mentioned. 
 
 It is curious to study the old authors in their explanations 
 of the diseases of wines. It is a succession of fantastical 
 interpretations, which they probably did not understand 
 themselves, and which are certainly unintelligible to lay- 
 men. 
 
 For instance, we read about "the intimate connexion of 
 the spirituous parts with the saline and mucilaginous mole- 
 cules," which is about equivalent to the " movement of the 
 humours" advocated by the old doctors, in treating affections 
 of which they were ignorant of the real cause. 
 
 The jleur (flower), Plate III., is the most common and 
 benign of wine diseases. 
 
 It only attacks wine when in contact with air ; the sur- 
 face of the wine becomes covered with white spots, formed 
 of a multitude of small organisms (microscopical fungi) 
 which are termed mijcoderma vim, which entangled together 
 form a regular scum, becoming wrinkled when further 
 developed. 
 
 This fungus is oval-shaped and reproduces by budding, 
 affecting on a microscopical scale the shape of the branches 
 of the common large oval-leaved cactus (Opuntia). It derives 
 its nourishment from the wine, living principally at the ex- 
 pense of the alcohol, the alcohol being transformed into 
 carbon dioxide and water, that is to say, consumed, and the 
 alcoholic strength of the wine naturally diminishes. 
 
 However, for the action of the mycoderma vini to be appre- 
 ciable, it requires to develop on a very large surface, compared 
 with the volume of the wine, that is to say the ullage of the 
 cask must be considerable. In ordinary cases where the 
 flower only extends over a small surface of wine as in an almost 
 filled cask, its action is quite insignificant. The case is the 
 same in a bottle standing upright and badly corked. It is 
 then only unsightly and does not injure the flavour in any 
 way. 
 
212 WINE-MAKING IN HOT CLIMATES. 
 
 It is not so with acetification or piqure, Plate III., which 
 develops under exactly similar conditions, and in most cases 
 follows the flower. 
 
 In the case of acetification the general characters are not 
 so pronounced at the start, instead of a regular scum com- 
 pletely obscuring the surface of the liquid, it is a light 
 transparent veil, a muslin instead of a thick blanket of flower. 
 When acetification follows the flower, we observe rents in 
 the blanket, rents which enlarge every day till the veil has 
 replaced the blanket. 
 
 This light veil is formed of micro-organisms known as 
 mycoderma aceti or diplococcus aceti, infinitely smaller than 
 mycoderma vini, and which can only be detected under a very 
 high magnifying power. 
 
 The cells appear to be shaped like two small balls, joined 
 together in the form of the figure 8 ; when they take posses- 
 sion of the wine the small balls join together forming chaplets, 
 when they become old, the chaplets dislocate and are replaced 
 by new ones formed of younger cells, while the old cells fall 
 inert to the bottom of the liquid, forming by their accumula- 
 tion, a viscous mass known as mother of vinegar. A very 
 characteristic property of the acetic ferment is its extreme 
 rapidity of reproduction when the conditions are favorable. 
 In 24 hours, according to Duclaux, an almost imperceptible 
 quantity of mycoderma aceti will cover a surface square metre 
 of liquid, producing, if we assume the layer to be composed 
 of one thickness of cells, 300,000,000,000' cells in that short 
 space of time. 
 
 The mycoderma aceti exerts an oxidizing action on alcohol, 
 transforming it into acetic acid and water. 
 
 Directly this action commences, the wine assumes a sour or 
 vinegar taste. This is a very serious disease, for all the ex- 
 tolled remedies are only insufficient palliatives, if the altera- 
 tion is at all marked. 
 
 Acetification often results in wine, through the acetification 
 of the marc during fermentation conducted with a floating- 
 head, and always takes place in casks which are left slightly 
 ullaged, especially in cellars where the temperature is 
 elevated. 
 
 Certain wines are more liable than others to become 
 attacked by mycoderma aceti; such are wines in which sugar 
 is left after incomplete fermentation, wines of low alcoholic 
 
CARE TO BE GIVEN TO WINE. DEFECTS, ETC. 213 
 
 strength, and wines worn out by age. Press wines are almost 
 invariably slightly sour, and are very liable to become attacked 
 by mycoderma aceti, if the casks are as already said not kept 
 quite full. 
 
 The remedies proposed are only palliatives, for, if it is pos- 
 sible by destroying the cause of the evil through killing the 
 micro-organisms to stop the progress of the disease, it does 
 not, however, suppress the acid taste existing before the 
 treatment. 
 
 To destroy the acetic acid formed, lime, carbonate of lime, 
 or what is the same thing, powdered marble, have been recom- 
 mended. 
 
 This is a bad remedy, and has the great disadvantage of 
 introducing into the wine a substance (lime) foreign to the 
 grape. The acid taste disappears, it is true, but its disap- 
 pearance is not persistent for all time, and the wine contracts 
 a strange taste which depreciates its value. 
 
 The saturation of the acetic acid by certain potash salts, and 
 particularly by neutral tartrate of potash, answers much better ; 
 in this operation ordinary tartar (bitartrate of potash) which 
 gradually subsides, and acetate of potash are formed. In this 
 case the disappearance of the acid taste persists, under the 
 conditions, however, that at the same time we stop or prevent 
 the disease from continuing its development. There are to 
 attain this end two means, apart from the general principle 
 of sterilization ; they are to fill completely and close the vessel 
 airtight, or to burn a sulphur wick in the empty space over 
 the wine, so as to surmount the wine with a layer of sulphurous 
 anhydride instead of air. Under these conditions the devel- 
 opment of the mycoderma aceti is completely arrested and the 
 wine does not move, a long as there are traces of sulphurous 
 fumes in the empty part of the cask, so that we may preserve 
 the contaminated wine for any length of time by the simple 
 additional precaution of renewing now and then the sulphurous 
 anhydride. 
 
 Acetification is a common disease, but riot so frequent, 
 however, as the tourne (turning), Plate IV. 
 
 The tourne, or turning, attacks the tartaric acid, whether 
 combined or otherwise, and transforms it into new com- 
 pounds, imparting to the wine characters which entirely 
 alter its nature. We have not to deal in this case, as in 
 the two preceding, with organisms living on the surface of 
 
214 WIXE-MAKIXG IN HOT CLIMATES. 
 
 the liquid, and which may be removed by simply protect- 
 ing the surface, but with organisms living in the midst of 
 the wine, which therefore render it cloudy, directly they 
 begin to multiply. 
 
 The tourne produces a special or peculiar cloudiness, which 
 is a very definite symptom of this disease. If we examine by 
 transmitted light, and in a thin layer, wine attacked by the 
 tourne, and which has been slightly shaken, a shimmering 
 appearance similar to the waves on watered silk is notice- 
 able from the movements of the microbes it contains. This 
 characteristic is 1 very transient, for the wavy appearance 
 soon stops after shaking, but it is sufficient to be acquainted 
 with this appearance to readily recognise it. 
 
 The ferment of the tourne has a filamentary shape, very 
 thin generally, and more or less curved according to its age. 
 It occasions the decomposition of the tartaric acid, several 
 different compounds resulting, such as tartronic, lactic, and 
 acetic acids, and it ends by destroying not only all the tartar 
 contained in the wine, but also that adhering to the wood or 
 the vessel containing the wine. 
 
 The tourne ferment is a veritable de-tartrater of the casks, 
 and this is a fact known long since, when wines did not 
 come out of the cellar directly after they were made, but 
 were often eventually submitted to the distiller. 
 
 Nowadays the disease is more rare, and it very seldom 
 becomes sufficiently developed to enable us to notice the 
 complete destruction of the tartar in wine. 
 
 The tourne attacks all wines of low alcoholic strength. 
 After the first invasion of mildew, the wines from mildewed 
 vines were attacked, even in viticultural regions where 
 tourne was previously unknown, by an alteration or disease 
 which was for a long time regarded as altogether different. 
 Gayon established by experiments and definite analyses that 
 mildewed wines were simply attacked by tourne. 
 
 When the disease is so far advanced that the taste of the 
 wine is sensibly modified, nothing can be done. In past 
 days the evil was not very great, because the still enabled 
 us to turn the diseased wine into fair spirit, easily saleable, 
 but to-day it is a disaster, for the market value depending 
 on the alcoholic strength is so low that the loss is almost 
 total. 
 
 If the disease has not made much progress, and if the 
 wine is still drinkable, the evil can fortunately be stopped 
 
PLATE IV. 
 
 Disease known as "Tourne. 
 
 Disease known as " Pousse." 
 
PLATE V. 
 
 known as " Aintrtume " (Bitter) (Young). 
 
 The same (Old). 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 215 
 
 by the general system of treatment of diseases due to micro- 
 organisms, which will be briefly described later on. 
 
 Pousse (pushing), Plate IV., is the sister disease of tourne, 
 but is less frequent, and only differs from it in this, that 
 amongst the products of the destruction of the tartar, pro- 
 pionic acid and carbon dioxide are formed. Carbon dioxide 
 is a gas, the same which is liberated during vinous fermen- 
 tation, and can only be dissolved in wine in limited propor- 
 tion. If we consider a well-bunged cask filled with wine 
 attacked by pousse, that is to say by a disease constituting a 
 veritable source of carbon dioxide, pressure will be developed 
 inside the cask, the result of which will be the pushing of 
 the heads outwards, hence the name pousse (pushing). The 
 pressure becomes so high sometimes that it results in the 
 bursting of the cask. 
 
 Pousse is due to a filamentary microbe, similar in form to 
 that of tourne^ but shorter, thicker, and straighter, while 
 that of tourne is always more of less curved. If the disease 
 has not progressed too far it may be cured by the same 
 means as those used for tourne. 
 
 The disease known as amertume (bitter), Plate V., is very 
 uncommon in the South of France. This is not due, as is 
 generally supposed, to the fact that the disease is special to 
 wines of grand cms, but simply that it requires a longer 
 time to develop and acquire all its characters, therefore it 
 can only be observed in old wines, and the wines of the South 
 of France never get old enough to give the disease time to 
 develop. As a matter of fact, the wines in the South of 
 France are more liable to get this disease than any other, 
 for the conditions of preservation and maturing are always 
 more unfavorable in a warm climate than in a cold one. 
 
 According to the researches of Pasteur and Duclaux, 
 amertume progressively destroys the glycerine in the wine, 
 forming volatile acids, amongst which acetic and butyric 
 predominate. It is probable that these are not the only bodies 
 formed, for, if this were the case, it would be difficult to 
 explain the bitterness, sometimes very intense, which charac- 
 terizes this disease. 
 
 Amertume is due to a filamentary microbe, longer and 
 thicker than those of either pousse or tourne, and which 
 differs from them by its ramified appearance, which is similar 
 to the branching of a tree. 
 
216 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 When the disease is starting, the ferment is more or less 
 isolated, relatively short and thick, and not ramified. It is 
 when ageing that it becomes ramified and encrusted with 
 colouring matter, which renders its detection more difficult, 
 but at the same time gives it a more distinguishing character. 
 Amertume is a disease to be feared in wines destined to be 
 laid down, but it has no importance in the case of wines that 
 are to be consumed young. 
 
 Graisse (fat) is a disease more peculiar to white wines, 
 and need not be much dreaded. It cannot be very common, 
 if we judge by the difficulty we find in procuring wine 
 characteristically attacked. Under its influence white wines 
 assume a viscous condition, and flow like oil from the tap, 
 and even, if more developed, like white of egg. 
 
 Scientists do not know exactly under the influence of what 
 decomposition this effect is produced. We can detect under 
 the microscope chaplets of little balls similar to those of the 
 mycoderma aceti, but rather larger, and surrounded by a 
 kind of mucilaginous matter, but that is all. A violent 
 stirring of the wine renders it quite fluid, and the addition 
 of tannin acts as a temporary cure, as was shown by Francois 
 very long ago. 
 
 The definite cure of this disease, like that of any other 
 disease caused by microbes, is easy to effect. 
 
 A few years ago a new wine disease (but very old, no doubt) 
 was discovered. It is known as mannitic fermentation, Fig. 
 57. P. Carles, of Bordeaux, had in 1891 pointed out the 
 
 presence of mannite in cer- 
 tain wines. After a few 
 experiments, he came to the 
 conclusion that mannite was 
 only found in wines made 
 from figs. According to 
 him the presence of mannite 
 in wine indicated adultera- 
 tion, the substitution or at 
 least the admixture of 
 grapes with figs. 
 
 Having had an oppor- 
 tunity of finding and char- 
 acterizing mannite in wines, 
 which we knew were made 
 exclusively from grapes, we 
 
 Fig. 57. Mannitic Ferment. 
 
CARE TO BE GIVEN TO WINE. DEFECTS, ETC. 217 
 
 were induced to study its origin, and were able to show that 
 we had to deal with a disease due to the action of micro- 
 organisms attacking not only fig wines, but also the pure 
 juice of the grape.* The same year we were able during a 
 trip to Algeria to extend and define our observations on the 
 subject, but were not able to isolate the living organism 
 which produced among other bodies, that which characterized 
 the disease, mannite.f 
 
 Gayon and Dubourg studied the subject again in 1894, 
 and thoroughly determined its evolution. They reproduced 
 it in healthy wine, by inoculating it with the microbes they 
 had succeeded in isolating. 
 
 Mannitic wines usually contain an excess of sugar, and the 
 total acidity is very great. The dry extract is very high, 
 not only through the presence of sugar, but even after the 
 sugar has been deducted. The bitartrate of potash does 
 not seem to be attacked, if the wine is only invaded 
 by the mannitic ferment, but it frequently happens that 
 the disease develops concurrently with tourm, which 
 destroys the tartar. 
 
 The ferment appears in the shape of short and very small 
 rods, immobile, which, instead of remaining independent 
 and disseminated in the liquid, gather together in great 
 numbers, forming colonies rather difficult to disintegrate. 
 It only develops in wine containing sugar, for it is from 
 its decomposition that mannite is formed. This disease is 
 therefore only to be feared in the case of wines contain- 
 ing sugar, or musts. It may develop during the alcoholic 
 fermentation, and seriously alters the wine when the trans- 
 formation of the alcohol through some cause or other lasts 
 too long, as happens when the temperature of the vat 
 exceeds the limit which wine yeast can support. 
 
 The conditions favorable to mannitic fermentation of 
 musts are naturally found in hot climates, and it was 
 in Algeria and Spain that this disease was first noticed. 
 Mannite only appears in French wines in exceptionally 
 hot years. Contrary to the opinion of certain authors, 
 mannitic fermentation is not a variety of tourne peculiar 
 
 * Memoir es de la Society des sciences phi/, et nat. de Bordeaux. 28th July, 1892 
 t L. Roos. Journal de pharm. et de chimie. 1893. 
 
218 WINE-MAKING IN HOT CLIMATES. 
 
 to sweet wines ; the differences are in fact numerous. The 
 following are those given by Gayon and Dubourg : 
 
 1st. The mannitic ferment differs in shape, dimensions, 
 and mode of grouping of the cells. 
 
 2nd. It does not develop in wines free from sugar where 
 the tourne ferment develops easily. 
 
 3rd. The latter does not develop in sweet liquids, especi- 
 ally in liquids artificially sweetened which are so favorable 
 to the former. 
 
 4th. The volatile acids produced during pure mannitic 
 fermentation are exclusively composed of acetic acid, while 
 if this acid exists in tourne wine there is side by side with it, 
 and in greater proportion, other volatile acids. 
 
 5th. While the tartar disappears in tourne wines it remains 
 unattacked in mannitic wines. 
 
 In fact, it is a disease which exists from the commence- 
 ment, and it is this which renders it so difficult to obviate. 
 It can only be avoided by attentively watching the tempera- 
 ture of the vat.* 
 
 There is a disease which has attracted considerable atten- 
 tion in recent years, known as casse (breakage), but the 
 origin of which does not seem to be due to microbes. 
 
 Prof. Bouffard f drew attention to this disease, which he 
 noticed was common in the 1893 wines, upon which he made 
 his first studies. 
 
 " The wine of a bright and clear colour in the cask becomes 
 turbid when aerated for three or four hours, and a brown-red 
 precipitate forms. If the wine is in a bottle kept still, the 
 decolouration.commences on the surface, where a small iride- 
 scent pellicle of colouring matter is formed which gradually 
 affects the lower layers of wine, the sides of the glass become 
 covered with an adherent deposit, and the wine becomes 
 almost entirely decolourized, assuming a characteristic 
 yellow-madeira colour. All these deposits consist of 
 colouring matter, insoluble even in concentrated tartaric 
 acid solutions. 
 
 " The wine does not disengage any gas, as happens in other 
 diseases. Its taste does not recall in any way pousse or 
 
 * Comptes rendug de I' Academic des Sciences. 9th April, 1894. 
 f Sterilization of the must previous to fermentation, and the use of pure 
 cultivated yeasts afterwards, is a means of avoiding the disease. (Trans.) 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 219 
 
 tourne. The taste may be compared to that of wines called 
 rancid or madeirized, which are the characteristic of very old 
 age." 
 
 Prof. BoufFard concluded that the idea of the action of a 
 microbe must be set aside, an opinion which has been accepted 
 since the publication of his work. He was also able to indi- 
 cate at the same time that sulphurous anhydride and heating 
 were efficacious remedies. 
 
 After Bouffard, various investigators studied this subject. 
 
 Gouirand, of the Viticultural Station of Cognac, has shown 
 that wine subject to casse (breakage) contains a soluble 
 ferment,* a diastase of the same nature as that recently 
 isolated by Bertrand and called oxydase, the characteristic 
 property of which is to fix the oxygen of the air on the 
 oxidizable matters with which the ferment is in contact. 
 The mechanism of casse will then be an indirect oxidation of 
 the colouring matter, resulting in it becoming insoluble* and 
 therefore precipitating. 
 
 Laborde, of the Agronomic Station of the Gironde, pointed 
 out one of the possible sources of the diastase,! namely, the 
 products of elimination of the Botrytis cinerea, the special 
 mould of the grapes which plays such an important part in 
 the vinification of Sauterne and Rhine wines. The diastasic 
 cause of the casse would seem to be admitted by every one ; 
 but Legatu, Professor of the Agricultural School at Moni> 
 pellier, has just given a new interpretation based on the role 
 of iron J: which has already gained a number of followers. 
 
 According to Legatu, casse is not due to a pure and simple 
 oxidation of the colouring matter, but to the oxidation of 
 a ferrous salt, which in that state is incapable of forming an 
 insoluble combination with the colouring matter, but which 
 acquires that property by changing to the ferric state. 
 
 " This new interpretation, according to him, is not contra- 
 dictory to the actually admitted influence of an oxydase, but 
 in the case studied, the part played by this diastase (if it 
 exists) has not consisted in rendering the colouring matter 
 insoluble, but in favouring the phenomena of oxidation 
 which always takes place in diluted solutions of ferrous salts. 
 The insolubility of the colouring matter follows in consequence 
 of the formation of a new ferric compound. 
 
 * Comptes rendus. April, 1895. 
 
 t Comptes rendus. 1896. 
 
 Comptes rendus. June, 1897. 
 
 10649. P 
 
220 WINE-MAKING IN HOT CLIMATES. 
 
 Legatn and myself tried to give this theory experimental 
 verification. Our researches are condensed in the following 
 note, abstracted from the Pr ogres agricole et viticole : 
 
 " It is clear that the above note brings a new element of 
 discussion to the scientific study of casse in wines, but does 
 not establish upon sufficient experimental basis the part 
 played by that element. 
 
 "It answers the question, it indicates a very plausible 
 theory, but does not solve the problem or establish that 
 theory. 
 
 u We have endeavoured by experimental researches re- 
 cently undertaken to gather facts which would throw some 
 light on the action of iron in the casse of wines. 
 
 "At that time of the year the difficulty of procuring 
 suitable samples of wines limited the extent of our 
 researches. It is difficult to find wines of good character 
 not containing any sulphurous acid, and it is not to wines 
 liable to casse, but already cured, that we- should have re- 
 course in order to systematically reproduce the casse. On 
 the other hand, the non-cured casse wines have already been 
 scibrnitted to treatment, to rackings at least, they are par- 
 tially attacked and their primitive state cannot be deter- 
 mined. However, the few samples we obtained enabled 
 us to observe facts which are in perfect accordance with the 
 new interpretation. 
 
 "It seems actually established that there are two 
 varieties of casse. First, blue casse, which is observed in 
 rich wines of an intense colouration, the true type of which 
 is met with in the Jacquez, vinified without the addition 
 of tartaric acid ; secondly, the brown casse characterized by 
 the more or less brownish colour of the precipitate, and 
 in the partial or total substitution of yellow for the original 
 colour. As will be seen, this distinction does not seem 
 fundamental. 
 
 " No wine susceptible to complete decolouration by ex- 
 posure to the air was noticed, one only took a slightly 
 madeira-red colour. 
 
 " It was found to be indispensable to study the precipitate 
 resulting from casse. 
 
 " We were surprised to find in this precipitate so far 
 considered as oxidized colouring matter a notable amount of 
 mineral matters, amongst which iron was in considerable 
 proportion. 
 
CARE TO BE GIVEN TO WINE. DEFECTS, ETC. 221 
 
 " Examples. A wine of Montauban attacked strongly by 
 brown casse, but, however, not completely decolourized, was 
 left for two days exposed to the. action of the air. 
 
 " The precipitate formed, collected on a Chamberland 
 candle, washed with distilled water till the washings were 
 no longer coloured, dried in a vacuum and incinerated 
 gave 
 
 Mineral matters ... ... 17'3 per cent. 
 
 Iron ... ... ... 5-0 
 
 "Wine made from Jacquez cepage, originating in the 
 Herault, not easily turning blue under the action of the 
 air, gave, however, for half a litre, 110 milligrames of dry 
 bluish-black precipitate, in which we found 2 per cent, of 
 iron together with silica. In this particular case, as with 
 all Jacquez, the wine had thrown down already a deposit 
 which was found to be rich in iron.* 
 
 tl All the precipitates from blue casse have been found to 
 be rich in iron. 
 
 " We therefore consider, as a constant and well-established 
 fact that a wine which breaks throws out iron. 
 
 "Is it not probable that blue casse is due to formation of 
 ferric tannate, while brown casse is due to the formation of 
 cenolate of iron ? The close relation between oenoline and 
 tannin f adds more weight to the above hypothesis, conse- 
 quently are we not naturally led to see the cause of the casse 
 in an excessive amount of iron. 
 
 " One of the first confirmations of this hypothesis must 
 be looked for in the comparison between the intensity of 
 the casse and the amount of iron. Now, one of us has 
 already established^ by numerous analyses that the 
 Jacquez wines, so predisposed to casse, are also in a general 
 way remarkably rich in iron. This is a clue, but the exact 
 determination of that element in the must and in the wine 
 
 * Prof. Bouffard (Ann. de I'Ecole not. d 1 Agriculture de MontpeUier, t. II. 
 1886) states "From facts observed, one may admit that the violet matter 
 (deposited by the Jacquez) is the result of oxidation, and perhaps, as we hope 
 to prove, a combination with the iron contained in wine, as a kind of tannate of 
 iron. The precipitation only takes place after the aeration through the staves 
 of the cask has been sufficient." Is not this the way casse proceeds ? Bouffard 
 distinguishes, however, this special casse from that we are studying, while it is 
 only regarded by Legatu and myself as a simple variation. (L.R.) 
 
 t L. Hugounenq. Recherches nouvelles sur les vins. Imp. A. btorck, Lyon. 
 
 J L. Roos, Giraud and David. Analyse chimique des vins de 1'He'rault 
 Recolte. 1890. Bull de la Soc. cenlrale d'agric. de V Herault. 
 
 p ^ 
 
222 AVINE-MAKING IN HOT CLIMATES. 
 
 directly after de-vatting would present more interest. How- 
 ever, this co-relation has already been verified for the Jacquez, 
 as also for other samples. 
 
 " As a second confirmation, a sound wine (but not charged 
 with sulphurous acid) should break when we increase the per- 
 centage of iron, a fact already established in the above note 
 and confirmed since by new trials with various ferrous salts. 
 
 " In the third place, the treatments indicated against the 
 natural casse, must be of the same value in wines in which 
 the casse has been induced artificially. Sulphurous acid is 
 so active against artificial casse that it is impossible to 
 obtain it even in wines which have simply been racked into 
 a sulphured cask. Example : A wine upon which trials of 
 artificial casse remained without results was subsequently 
 found to contain 32 milligrammes of sulphurous acid pel- 
 litre ; re the heating, we have only studied its effect in an 
 incomplete way, and wall only mention that the absolute 
 efficacy of this cure has been disputed. However, from our 
 first researches it is evident that wine acquires by heating 
 the property of holding the iron in solution more perfectly. 
 There is therefore in the above results a point strong enough 
 for an interpretation of casse independent of any oxidizing 
 diastase to which the disease is to-day attributed.* 
 
 " It is interesting to try and produce the phenomenon . of 
 the casse under conditions excluding the presence of 
 diastase. 
 
 "To arrive at this, renoline free from iron and even 
 mineral matter was isolated by the Hugounenq process. 
 The use of strong alcohol for dissolving the ceuoline excludes 
 any diastase. The product of this dissolution was used to 
 colour an alcoholic solution of tartaric acid containing some 
 iron introduced in the form of ferrous hydrate. The mixture 
 became turbid a few hours afterwards, forming a reddish 
 precipitate similar to that of brown casse. At the same 
 time the liquid was covered with an iridescent pellicle, as 
 observed in natural casse, and affected the reddish-yellow 
 colouration so characteristic of casse wines. This fact leads 
 us to think that the presence of an oxydase is not indispen- 
 sable to the casse. 
 
 " However, the facts given above seem to have as much 
 weight as those advanced in favour of the diastase theory. 
 
 * Theory of Gouirand, supported by numerous experimenters. 
 
CAEE TO BE GIVEN TO WINE. DEFECTS, ETC. 223 
 
 " We may even produce artificial casse, absolutely similar 
 to the natural casse, while the oxydases only furnish, accord- 
 ing to certain authors, a near image. 
 
 " And, what is more, the knowledge of oxydases and of 
 their mode of action was until recently very vague. During 
 the course of our researches Bertram! * established that a 
 (dose behaviour existed between the oxidizing action of 
 those bodies and of manganese, in the form of manganous 
 hydrated salts, as the only conveyer of oxygen in the pheno- 
 menon of oxydation observed. The intervention of man- 
 ganese being proved indispensable to the action of the 
 oxydases, did not surprise us much. We are in presence, 
 as in our own argument, of a metallic oxide. 
 
 " The manganous and ferrous salts have very similar 
 properties, from the point of view of the transformations 
 brought about by oxygen. With regard to this, the ferrous 
 salts have even a more marked activity. 
 
 " Manganese exists in wines, but in scarcely detectable 
 quantities. We cannot define its action in casse, but may 
 state that the precipitates obtained in the wines affected by 
 casse naturally, are always free from it. Manganese only 
 exists in the liquid. 
 
 " As we were able in our experiments to produce the casse 
 in a liquid completely free from manganese, we do not 
 consider for a moment that it is necessary to invoke that 
 metal to explain the natural casse. 
 
 " In all cases the phenomenon of the precipitation remains 
 a function of the iron. 
 
 " In short, in this particular case, we do not see the 
 utility of manganese united or not to a diastase as an 
 oxidizing agent ; anyhow, it does not enter into the compo- 
 sition of the precipitate." 
 
 Soon after its publication, Legatu's paper was the object of 
 a violent critique from Cazeneuve. This criticism, remark- 
 able for its vivacity, does not adduce any serious argument 
 against Legatu's theory, which we found, on the contrary, 
 strongly supported by the works of various experimenters. 
 
 " Sometimes we lose sight of the fact," says Bourquelot,t 
 "that the oxydases may be produced with oxydizing matters 
 which cannot be looked upon as true oxidising ferments." 
 
 * Comptes rendus de I' Academic des Sciences. 14th June, 1897. 
 t Journal de Pharmacie et de Chemie. May, 1897. 
 
224 WINE-MAKING IN HOT CLIMATES. 
 
 Villiers* shows that in a purely inorganic liquid, through 
 the action of a nianganous salt, very important oxidizing 
 phenomena result, where the manganese can only be looked 
 upon as an oxygen conveyer, considering the great quantities 
 fixed through its action. 
 
 A. Livache* studied the action of different metallic oxides on 
 the oxidation of linseed oil, and quotes manganese as the most 
 active, but similar effects were obtained with other oxides, 
 notably that of iron, which gave results of the same class. 
 although taking longer to obtain. Bertrand, to whom is due 
 the most interesting work on the oxidizing ferments, has just 
 found a close co-relation between their action and the presence 
 of manganese in their composition.* 
 
 Legatu's theory does not negative the existence of oxidases, 
 it only establishes that the casse of wines may not be due to 
 diastase, or at least admitting a casse due to diastase, there is 
 another, quite similar, in which the oxidizing ferment plays 
 no part. 
 
 The effect of heat in preventing casse is often advanced to 
 strengthen the hypothesis of a diastase, as soluble ferments are 
 always paralysed by heating. But we have seen that wine 
 acquires through heating the property of retaining the iron 
 compounds in solution. 'We also know that organic com- 
 pounds exist, into the composition of which iron enters, and 
 which do not give any reaction for that metal. Would not, 
 in this particular case, the action of the heat be to fix the 
 iron in a state unattackable by oxygen ? Whatever it be, if 
 we admit, and this is generally admitted even by the advo- 
 cates of diastase, a casse special to the Jacquez, and closely 
 related to the excessive quantity of iron those wines contain, 
 why deny the existence and the theoretical interest of a simi- 
 lar affection in the wines of other cepages, the analyses of 
 which show quantities of iron equal and even superior to that 
 contained in Jacquez. 
 
 TREATMENT OF DISEASED WINES. 
 
 Heating. Whether due to microbes or not (such as casse), 
 the diseases above mentioned all give way to heating. 
 
 Observations conducted systematically have shown that no 
 living being, neither any reproductive organ of a living being 
 (seed, egg, spore) can resist a temperature of 120 C. At 
 
 * Comptes rendus. June, 1897. 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 
 
 that temperature, dry or moist, all life is suppressed; but if, 
 instead of operating in air or water, we operate in another 
 gas, vapour, or liquid, the temperature may be considerably 
 lowered and still remain just as effective. 
 
 Thus, in the case of wine, which is, after all, a solution of 
 alcohol and different acid substances, it is sufficient to raise 
 it to a temperature of 60 C. (140 F.) for a few minutes to 
 annihilate any living organism. 
 
 Heating is, therefore, a veritable sterilization based upon 
 the destruction of all living organisms, and we see what can 
 be expected from the application of such a process. 
 
 The description of the machines for the heating of wines, 
 Pasteurizers, or CEnotherms, does not come within the scope 
 of this work. The reader will find all desirable information 
 in the study published by Prof. U. Gayon on these machines.* 
 
 We will simply give a condensed account of the conditions 
 necessary for efficient pasteurization. The wine to be heated 
 should be almost clear, for the solution of the matters in 
 suspension, under the influence of heat, is to be feared 
 solution which is always accompanied by a defective taste. 
 We should, therefore, if not filter at least rack, and avoid the 
 passage of the turbid part through the Pasteurizer. 
 
 For the wine to preserve all its qualities, and not to lose 
 any colour through the heating, it must pass by the required 
 temperature (60 C.), and come down to its initial tempera- 
 ture without coming in contact with air, so as to prevent the 
 action of oxygen taking place during any of the phases of the 
 operation. The extreme temperature which the wine should 
 reach must not be the average of very different temperatures 
 applied to different parts of the wine, but only the average 
 of very close temperatures. If, for instance, we pass wine 
 through a coil submerged in constantly boiling water, coupled 
 with a worm submerged in cold water, although the wine at 
 the exit may be obtained at the same temperature as at the 
 entrance, the heating is defective. In this case, the wine in 
 immediate contact with the metal would be submitted to a 
 high temperature (almost 100 C.), while that in the centre 
 of the tube would only be slightly heated. The average tem- 
 perature resulting from the mixture of these will, no doubt, 
 be sufficient to insure sterilization, but the wine will have 
 contracted a special cooked taste, because certain parts have 
 been overheated. 
 
 * U. Gayon. Etude sur les appareils de pasteurization de vins. Extraitde 
 la Revue de Viticulture. Feret et Fils. Bordeaux. 
 
226 WIXE-MAKIXG IX HOT CLIMATES. 
 
 In order not to lose the beneficial action of pasteurization, 
 and avoid contamination of the wine, it should be passed 
 direct into sterilized casks. In most cases, washing the 
 casks with boiling* water is sufficient, but the sterilization 
 is more certain, and it is more convenient in practice to 
 steam them. 
 
 The wine heated under these conditions has nothing to 
 fear from diseases, and will not acquire as a result modi- 
 fications of colour or taste. When kept in well-bunged 
 casks, it may be preserved without further alteration of 
 any kind, and has even acquired a special resistance to the 
 germs which might accidentally contaminate it. Heating 
 has made great strides during the last few years, but has 
 still greater progress to make, actually pasteurizers are 
 always to be found in wine merchants' cellars, even of 
 medium importance ; but they are still rare in the vine- 
 grower's cellar. However, the advantages are so definite, 
 that little by little they force their way into, and will very 
 soon be part of the current material of every cellar. 
 
 FILTERING AND FINING. 
 
 To cure diseased wine, or to be more precise, to hinder 
 the development of the disease, we should kill the microbes 
 causing it, or separate them completely from the wine in 
 which they exist, Filtering is a solution of this problem, 
 but is only efficacious if it is perfect, and to be perfect it 
 requires expensive apparatus provided with powerful me- 
 chanical appliances. 
 
 A large filtering plant was established quite lately at 
 Algiers. The filters employed were of the well-known type 
 Chamberland porcelain candle, tile results obtained with 
 this plant were equivalent to those given by heating from the 
 point of view of sterilization, but this is a remedy only 
 practical for cellars in the immediate neighbourhood of 
 such a plant. 
 
 Most filters do not insure sterilization. Their effect i& 
 excellent in many cases, but quite useless when we have 
 to deal with diseases due to microbes. The disease is 
 almost preferable, when we have not at disposal a good 
 pasteurizer. 
 
 The matters used for fining are distinguished according 
 to their mode of action. Finings only acting mechanically 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 'J^T 
 
 (sand, Spanish clay, paper pulp). Finings forming with 
 the acids of the wine, partly soluble salts, chalk, marble^ 
 powdered oysters, plaster (all useless), and last the finings 
 coagulated by substances in the wine. 
 
 The latter class only are true finings, and should alone 
 be used. They are all bodies known in chemistry as 
 albumenoids, all acting in the same manner, and forming 
 with tannin insoluble flocculent precipitates of a density 
 slightly greater than that of the wine, and which con- 
 sequently only gradually settle to the bottom dragging 
 down as in a net of infinitely small meshes, all the solid 
 particles, whatever their tenuity may be, which float in the 
 midst of the wine. This makes fining a very special class 
 of filtration. 
 
 The different albumenous clarifiers are : several albumens., 
 white of egg, blood, milk, gelatine, isinglass. 
 
 These substances are the base of all the products prepared 
 by the trade, and sold more or less modified under various 
 names and aspects. The commercial liquid finings are always 
 solutions of these compounds rendered non-putrescible by 
 the addition of antiseptics, very often sulphurous acid> 
 combined or not, but, unfortunately, sometimes also bodies 
 interdicted in the manipulation of wine, and which are found 
 afterwards in the treated wines, such as boric acid and 
 salicylic acid. The possibility of getting involved very 
 innocently in a police prosecution case should render the 
 proprietor very distrustful of these finings. This is to be 
 regretted, for the preliminary preparation required by the 
 albumenoids used for fining is generally very well done by 
 the trade. 
 
 The egg albumenoids are used without any preparation 
 other than separation from the yolk and beating up with 
 water. 
 
 Fresh blood, or better, serum, that is to say, the clear 
 amber-coloured liquid which separates after coagulation, is 
 used without any further preparation. 
 
 Natural milk is only used for the clarification of vinegar. 
 
 Whites of eggs are usually used in the proportion of two- 
 per hectolitre (four per hogshead). Blood, or serum, in a 
 quantity of 50 cubic centimetres per hectolitre. 
 
 In both cases the method of operating consists in diluting 
 the clarifying matter with a small quantity of water (the 
 five thousandth part of the volume to be treated), pouring 
 
228 WIXE-MAKIXG IX HOT CLIMATES. 
 
 the prepared mixture into the wine, and energetically rousing 
 by appropriate means, according to the capacity of the 
 vessel, and allowing the wine to remain undisturbed until 
 the complete subsidence occurs of the precipitate formed. 
 The subsidence takes usually from three to eight days, after 
 which racking separates the wine perfectly bright. 
 
 Egg and blood albumen are both sold in commerce in a 
 solid state, but in that form are always expensive, and lose 
 their main advantage, which is the simplicity of their 
 manipulation when liquid. 
 
 Gelatine requires a rather longer preparation. It is found 
 in commerce in the shape of transparent sheets, slightly 
 yellow or quite colourless if the gelatine is pure. It swells 
 without dissolving in cold water, but dissolves very readily 
 in warm water. Gelatine is obtained by boiling bones, 
 tendons, cartilage, and other abattoir waste at a temperature 
 over 100 C. under pressure. 
 
 Dissolved in water, it has the property of forming a jelly 
 on cooling, if the solution is sufficiently concentrated. AVe 
 should, therefore, be careful when preparing it as a simple 
 solution in warm water, to dilute it enough to avoid coagula- 
 tion when cold. In the proportion of 5 per cent, the 
 dissolved- gelatine remains liquid at ordinary temperatures. 
 The liquid clarifiers with a gelatine base, sold in commerce, 
 -are almost always stronger than 5 per cent., but to keep 
 them liquid they are heated under pressure at a temperature 
 of 128 C. By this treatment the gelatine loses its charac- 
 teristic property of forming, with tannin, an insoluble com- 
 pound, and that of solidifying on cooling. 
 
 If, perhaps, it is of some utility for the trade to obtain 
 concentrated solutions, it is not necessary for the wine-maker, 
 -and the solutions at 5 per cent., which any one can make 
 without the use of special appliances, will render the same 
 services. In cases where the proprietor requires to keep the 
 gelatinous solution prepared in this way he should add to 
 it 1 per cent, of bisulphite of potash to render it 
 unputrescible. 
 
 Two hundred cubic centimetres of this solution are sufficient 
 to clarify one hectolitre (22 gallons) of wine, the operation 
 being conducted in exactly the same way as with white of 
 egg or blood. 
 
 Fish isinglass obtained by the desiccation of the natatory 
 bladder of certain fish is very recommendable for white 
 
CABE TO BE GIVEN TO WINE. DEFECTS, ETC. 229 
 
 wines. Its use seems at first very expensive, as the price of 
 a good quality is 30 francs per kilogramme, but the quantity 
 necessary is so small that the price of the fining for one 
 hectolitre is not, after all, much greater than when using 
 gelatine. 
 
 Two grammes of fish isinglass are ample to clarify one 
 hectolitre of white wine. The preparation of this isinglass 
 takes longer than that of gelatine. The sheet of dry isinglass 
 is first split in three thin sections, then placed in a vessel, 
 covered with cold water, and allowed to remain for 10 or 12 
 hours, during which it swells. 
 
 " After that the mass is sprayed with boiling water, beating 
 it continually meanwhile. At first it forms a thick paste, 
 becoming almost fluid when the total quantity of water 
 added reaches 50 litres for one kilogramme of isinglass. 
 
 The main element for success in this preparation consists 
 in the thorough division of the isinglass. If we possess the 
 means of rasping it, and making a kind of coarse powder, a 
 thick liquid free from lumps is then easily made. If means 
 of rasping it are not at hand, the emulsion may be heated 
 for a few minutes, but it is better in this operation not to 
 let the temperature rise to 100 C. 
 
 Two hundred cubic centimetres of this solution of fish 
 isinglass of 2 per cent, strength will be sufficient to fine one 
 hectolitre of wine. The 200 cubic centimetres should be 
 first diluted with half a litre of water, adding it by instal- 
 ments, the mixture is then further diluted with wine, and 
 introduced into the cask, stirring energetically during the 
 addition, and then left alone during sedimentation. 
 
 It goes without saying that the wine-maker may insure 
 the preservation of the prepared solution of fish isinglass, in 
 the same way as in the case of gelatine, by adding 1 per cent, 
 of bisulphite of potash, and may, therefore, in one single 
 operation prepare the fining required for a whole year. 
 
 Precautions to be taken to insure the efficacy of fining. 
 For fining to give good results the treated wines should 
 remain perfectly still during the whole time necessary for 
 the deposition of the fluffy precipitate formed through the 
 action of the tannin in the wine on the albumen or gelatine. 
 It is sometimes said that wines do not take, or do not take 
 the finings easily, this may be due to different causes. 
 
 One of the most frequent in white wines is deficiency of 
 tannin, certain kinds of white wines, especially those obtained 
 
230 WINK-MAKING IN HOT CLIMATES. 
 
 from red grapes by the fermentation of the first fraction 
 of drained juice, are very poor in tannin, and consequently 
 cannot produce the coagulation necessary to insure the 
 success of the operation. The remedy consists in the 
 addition of tannin to the wine in a quantity of 25 to 30 
 grammes per hectolitre. 
 
 It is easy to place in evidence a deficiency of tannin by 
 the following simple process. 
 
 Portions of the wine to be fined are placed in two glasses ; 
 in one in its natural state, in the other with the addition of 
 tannin. After the tannin is dissolved, add to both in equal 
 amount (very small) four or five drops of the fining to be 
 used. If the wine is rich enough in tannin to take the 
 fining, the precipitation will be almost the same or equal in 
 both glasses, while if the wine requires the addition of tannin, 
 the precipitate will be much heavier in the glass to which 
 tannin was added. 
 
 We may again place the fining in one hectolitre of wine, 
 and stir in a small quantity of dissolved tannin. If the 
 precipitate does not increase, the wine will not require the 
 addition of tannin. 
 
 Another cause of failure in the fining of wines results from 
 the wines being saturated with carbonic acid gas, which, 
 gradually disengaging, forms little bubbles bursting at the 
 surface, carrying during their upward movement small par- 
 ticles of fining, which remain suspended in the wine. This 
 trouble may be avoided by racking in presence of air, when 
 the wines abandon enough carbonic acid gas for that re- 
 maining to keep in solution during slight alterations of" 
 atmospheric pressure. 
 
 Finally, another cause of failure is met with in wines 
 attacked by microbe diseases, if we do not previously 
 paralyze the microbes. While at work the microbes pro- 
 duce movements in the wine, by gaseous disengagement or 
 formation of liquid currents ; these are no doubt slight,, 
 but sufficient to prevent the normal action of the fining. 
 
 They may be paralyzed by the use of sulphurous acid 
 in a quantity of 10, 12, or 15 grammes per hectolitre.. 
 The most convenient way of applying the sulphurous acid 
 is that already described in the vinification of white wines, 
 namely, sulphwing with the pump. If the reader refers 
 back he will see that the operation is easy, and does not 
 complicate the operation of fining. (See page 178.) 
 
CAKE TO BE GIVEN TO WINE. DEFECTS, ETC. 231 
 
 
 
 Let us suppose a cask of wine of 200 hectolitres attacked 
 by toarne is required to be fined, and that the quantity of 
 sulphurous acid necessary to paralyze the microbe be 12 
 centigrammes per litre, or 12 grammes per hectolitre, the 
 mode of operation would be as follows : Weigh 1,200 
 grammes of sulphur, burn it, and force the vapours into 
 the cask, as previously explained; this being done, place 
 in a tub the necessary quantity of lining, 40 litres of a 
 solution of gelatine of 5 per cent, strength (i.e., 200 cubic 
 centimetres per hectolitre), dilute with an equal volume 
 of wine, then with the pump used for sulphuring force 
 the mixture into the cask, and continue pumping air into 
 it after the tub is emptied to insure thorough agitation, 
 after that wait till the clarification is complete. 
 
 The fining with such a quantity of sulphurous acid pre- 
 sents evidently certain inconveniences, for the colour 
 diminishes and the fined wine acquires a decided taste of sul- 
 phurous acid. However, these faults are only transient, the 
 colour comes back after one or two rackings, and the sul- 
 phurous acid taste fades away completely, especially if the 
 sulphuring has been done with pure sulphur, and not with 
 sulphured cloths. For the sulphur compounds formed by 
 the burning of cloth, although in very small quantity, give 
 rise to a very persistent smell in the wine. 
 
 Notwithstanding these inconveniences, the fining after pre- 
 vious sulphuring is excellent for all diseased wines, which 
 after such a treatment will be able to keep, and which other- 
 wise would certainly have entailed loss. 
 
 Sulphuring, followed by fining, is after all similar in its 
 mode of action and effect to the use of different commercial 
 mixtures, placed for sale under high-sounding names, and at 
 prices still more high-sounding. All those which are lawful 
 are mixtures of sulphurous acid and albumenoids, obscured 
 under trade names ; many are excellent, and could be recom- 
 mended if it were not for their exorbitant price. If the 
 proprietor wishes to use ready-prepared finings, care should 
 always be taken to apply to firms of repute, and insist upon 
 a guarantee as to the composition, if it is desired to avoid 
 the risk of prosecution. 
 
232 WINE-MAKING IN HOT CLIMATES. 
 
 APPENDIX. 
 
 Extract from " The Vine in Australia" by Dr. A. C. Kelly. 
 Published in 1841. 
 
 CHAPTER ON FERMENTATION. 
 
 "In the warmer parts of Australia the vintage begins 
 sometimes in February, and is generally over in March, a 
 season when the weather is occasionally very hot. It is by 
 no means an uncommon occurrence for the temperature to 
 remain for some days above 90 F. during the day, and 
 never under 80 at night. Must, fermenting under such 
 heat, rises many degrees above the highest temperature of 
 the air ten degrees probably. The effect of this high tem- 
 perature is by no means so injurious as might have been 
 anticipated. Much good wine has been made whose tem- 
 perature during fermentation has risen to 100 F. The 
 temperature of 86 is the limit beyond which a sound 
 healthy fermentation cannot be maintained in beer and other 
 worts, and such was thought to be the case also with grape 
 must ; the opinions of modern oenologues, however, have 
 undergone a change on this subject. "An acquaintance 
 with many details with which we are still ignorant is, how- 
 ever, necessary in order to investigate thoroughly the in- 
 fluence of temperature upon a well-tasted wine, which 
 should not spoil with age. The grapes of each country, 
 ripened under different degrees of summer warmth, and 
 very unequally rich in constituents, require different 
 temperatures during fermentation ; and different tempera- 
 tures are required for grapes which are the product of a 
 warmer or colder summer. But we are still ignorant on 
 these points. All we know is, that a high temperature 
 during autumn promotes fermentation, and a low one is 
 detrimental to it ; that inequality of temperature during 
 fermentation is extremely injurious, and not infrequently 
 spoils the wine altogether."* Baron Liebig, in writing 
 
 * Mulder. Chemistry of wine. 
 
APPENDIX. 233 
 
 to the late Mr. King on the wines of New South Wales, 
 says : " As the wine of Irrawang contains an ample 
 quantity of saccharine matter, I deem it expedient that you 
 should allow it to ferment at the highest possible tem- 
 perature." 
 
 The illustrious chemist, however, would surely set some 
 limit to the temperature. One thing is certain, that it is 
 only very strong must which can be allowed to rise so 
 high as it does with us in Australia. The weak must of 
 the North of France and the Rhine, whose specific gravity 
 may be about 106, would pass into vinegar were it ex- 
 posed to a temperature of 90 and upwards. 
 
 In colder countries large vats are employed as best suited 
 to maintain the temperature of the fermenting mass, but 
 they would be objectionable where it is desirable to keep 
 the vats cool. How to keep down the temperature of the 
 fermenting must, is the most difficult problem the Australian 
 wine-grower has to solve. " Experience has taught us 
 that the temperature of fermenting wine cannot be kept 
 down by the use of underground cellars, unless the quantity 
 be insignificant. We prefer a wooden building above ground, 
 with the means of admitting free currents of air on all 
 sides. Any accession of heat which a hot day may occasion 
 is more than compensated for by the cool night air, which 
 has free admission on all sides. A large body of wine will 
 rapidly heat an underground cellar, and it caimot be cooled 
 down again for many days."* 
 
 " A free admission of air to the surface of the fermenting 
 liquor has the effect of keeping down the temperature. To 
 this we shall revert shortly. Where it is desirable to exclude 
 the air, as in the fermentation of red wines, some other 
 means are required to prevent the fermenting liquor from 
 rising to an excessive heat, as it must do under a tempe- 
 rature of the air of 90 or upwards. This may be effected by 
 means of a refrigerating apparatus such as the annexed, which 
 is sufficiently simple to require no particular explanation. It 
 is simply a pipe formed like the worm of a still, through 
 which the cold water from a cistern flows, and is dis- 
 charged again outside. The entrance and exit parts of 
 the pipe are placed close together, in order to interfere as 
 little as possible with the fixing of a false lid, and also 
 
 * Rough Notes Sir W. Macarthur. 
 
234 WINE-MAKING IN HOT CLIMATES. 
 
 to facilitate the strengthening it by a frame. By means 
 of a long flexible tube, to Jit on by a coupling screw, the 
 apparatus may be applied to a vat at a distance from 
 the cistern. The supply of water for the cistern must of 
 course be from a well or underground tank, whose tem- 
 perature is moderate ; and care must be taken that it 
 does not lower the temperature too much. This refrigerator 
 has been used with excellent effect in this colony, but was 
 given up from a dread, perhaps a needless one, of the effect 
 of the metal, block tin, upon the wine. The same apparatus 
 is used during warm weather in some breweries in Britain, 
 where great care is employed in conducting the fermenta- 
 tion, and where it is essential to maintain a steady tempera- 
 ture. When the temperature is low the same may be used 
 to keep up sufficient heat in the liquid by passing hot water 
 through it. 
 
 " The chief objection that can be brought against this 
 refrigerator is the material of which it is constructed. The 
 powerful action of the tartar upon metals, already alluded 
 to, forbids the employment of any metallic implements 
 which are to come in contact with grape-juice. Silver is the 
 only metal which is not much acted on by tartar ; and a 
 copper tube, electro-plated at that part which is immersed 
 in the fermenting must, would, probably, be not too expen- 
 sive to forbid its use. An iron or copper tube, enamelled, 
 would also be an excellent material for the purpose. Glass 
 might be employed for the construction of refrigerators ; it 
 could be protected by a wooden frame, and as it is only the 
 portion immersed which is affected by the tartar, the entrance 
 and exit pipes may be constructed of metal. The only 
 objection to glass is its slow conducting power, but this may 
 be so far obviated by giving it a larger surface. 
 
 " It is surprising to find so little attention paid to tempera- 
 ture in the fermentation of wine in these colonies. If the 
 general principles of fermentation are of universal appli- 
 cation, we have no reason to treat grape-juice as if it were 
 an exception ; and expect that it can be fermented success- 
 fully when we disregard the conditions under which alone a 
 healthy fermentation can be conducted. Grape-juice cer- 
 tainly ferments more readily and completely than any other 
 fermentable substance, and has, perhaps, less tendency to 
 go into the acetous 'state ; and wine-makers, trusting too 
 much to its power to resist the deteriorating influences to 
 
APPENDIX. 235 
 
 which it is often exposed, do not consider it necessary to 
 abide by the laws which regulate the fermentation of other 
 substances, but take extreme liberties with the grape must. 
 For example, the temperature of the fermenting must may 
 rise to 100, and sometimes several degrees above it, and 
 the resulting wine may be sound and good. The conclusion 
 drawn from this is that wine may be fermented at a very 
 high temperature without injury. Not without injury cer-, 
 tainly, as the following experiment shows : A quantity of 
 purple grapes was crushed during very hot weather, the 
 temperature of the air being above 90 during the day and 
 never under 80 at night. The must and skins were put 
 into a vat of 250 gallons, and a false lid placed as usual to 
 keep down the mark. There was more than sufficient to fill 
 the vat to the proper height ; and the remainder, about 
 40 gallons, was put into a small vat (a port wine pipe having 
 the head out), a false lid was also fitted into this. The fer- 
 mentation commenced in each the following day, and in two 
 days the temperature rose considerably during the tumul- 
 tuous fermentation ; but that of the larger vat was, at least, 
 8 higher than the temperature of the smaller. After this 
 the progress of the attenuation showed a marked difference 
 in the two vats. In the smaller it went on steadily, and in 
 three days after the height of the fermentation it had fully 
 attenuated itself, giving a specific gravity of 100, and was 
 racked off clear and in fine condition ; whereas the larger 
 vat attenuated very slowly. On the third day after the 
 violent fermentation its specific gravity was still 102*5 ; the 
 following day it had come down very little, showing 102, 
 and was full of yeasty matter floating through it. It was 
 racked off into casks, to undergo the secondary fermentation ; 
 and, although eventually it attenuated after some time, it 
 was an inferior wine to that drawn from the smaller vat. 
 
 " It has been often remarked that the first experiments in 
 wine-making are generally the most successful, but it is easy 
 to divine the reason of this. The first quantities made are 
 generally very small, 40 or 50 gallons or less ; the tempera- 
 ture of so small a body of fermenting liquor seldom rises 
 high, and the process goes on under much more favorable 
 circumstances in this respect than in the subsequent vintages, 
 when the fermentation is generally conducted in quantities 
 of from one to several hundred gallons, when the increase of 
 temperature is necessarily greater. 
 
 10649. 
 
236 WINE-MAKING IN HOT CLIMATES. 
 
 " The fermentation of grape-juice is so entirely a natural 
 process, and goes through its course so perfectly, under 
 favorable circumstances, that we are apt to become careless, 
 and say that we are trusting the process to nature when, in 
 fact, we are counteracting her operations, and going in direct 
 opposition to the conditions under which fermentation can 
 proceed with success. There certainly exists in the grape a 
 vital energy, a sort of vis medicatrix, which not only resists 
 many evil influences to which it is exposed, but seems also 
 to correct them when they have occurred. 
 
 " To none of the conditions necessary to a sound healthy 
 fermentation ought we to pay more attention than tempera- 
 ture ; and there is, probably, none which is so much 
 neglected. This arises, doubtless, from the difficulty, and, 
 I may say, the supposed impossibility of counteracting the 
 excessive heat of the climate. The construction of an 
 apparatus for keeping down the temperature, of the nature 
 and form already alluded to, would be neither difficult nor 
 costly, and of its beneficial influence on the fermenting 
 process, and the resulting wine, there can be little doubt, for 
 the great majority of our wines are fermented at too high 
 a temperature. When we find writers such as Liebig and 
 Mulder recommending a high temperature for the fermen- 
 tation of the wines of warm climates, we solace ourselves 
 with the idea that we are on the safe side in this respect, 
 forgetting that what these writers would consider a high 
 temperature is, probably, 86 F., the highest point assigned 
 to a healthy fermentation ; but supposing that they allow a 
 higher limit say 10 above it, still this is far below what 
 the fermenting vats of these colonies often attain, for in 
 many cases they must rise 10 degrees higher still, to 106, 
 or 20 above the limit already indicated as that beyond 
 which the fermentation does not go on favorably. This is a 
 temperature surely never contemplated by any of these 
 writers, and which no must ought ever to be allowed to 
 attain. 
 
 a The effect of a very tumultuous fermentation in beer, 
 caused by a high temperature, is thus described by Dr. 
 Ure * : < When the action is too violent, these barmy 
 glutinous matters get comminuted and dispersed through 
 the liquor, and can never afterwards be thoroughly 
 
 * Dictionary of Arts and Manufactures. 
 
APPENDIX. 237 
 
 separated. A portion of the same feculent matter becomes, 
 moreover, permanently dissolved during this furious commo- 
 tion by the alcohol that is generated. Thus, beer loses not 
 merely its agreeable flavour and limpidity, but is apt to 
 spoil from the slightest causes. The slower, more regularly 
 progressive, and less interrupted, therefore, the fermentation 
 is, so much better will the product be.' If such are the 
 results of a too violent fermentation in beer, we cannot 
 doubt that it must also have an injurious effect on wine. 
 
 " The grapes of the warm districts of these colonies, which 
 attain a specific gravity of 112, or more, are able to bear, 
 and probably require, a very high temperature to complete 
 their fermentation ; the exact limit we cannot define, but we 
 may venture to say that 95 is a temperature beyond which it 
 would not be advisable to allow any wine to rise, and probably 
 90 is the highest it ought ever to attain" 
 
 Q2 
 
238 WINE-MAKING IN HOT CLIMATES. 
 
 THE CONTROL OF THE TEMPERATURE IN 
 WINE FERMENTATION. 
 
 BY A. P. HAYNE,* DIKECTOK OF VITICULTURE, CALIFORNIA. 
 BULLETIN No. 117, UNIVERSITY OF CALIFORNIA, 1897. 
 
 The Control of the Temperature. The fermentation of 
 wine must or the juice of the grape results in the main in the 
 splitting up of the sugar it contains into almost equal parts 
 of alcohol and carbonic acid gas. While there are other 
 products of fermentation, it is not essential for our immediate 
 purpose to dwell on them in this connexion. The transfor- 
 mation of sugar into carbonic acid gas and alcohol is a 
 chemical action caused by minute plants or ferments called 
 yeast. It is well known that all chemical changes of this 
 sort produce heat ; and thus it will be seen that the tempera- 
 ture of a fermenting mass of a sugar solution (grape juice), 
 while it depends to a certain extent upon the outside tem- 
 perature, is chiefly dependent upon the amount of heat 
 generated within the tank itself. The amount of heat then 
 that is produced in a fermenting tank depends upon, first, 
 the per cent, of sugar in the must and the quantity of 
 must ; second, the facilities offered by the tank and air for 
 carrying off the heat generated by fermentation, or con- 
 ductivity of the tank walls, the amount of surface exposed 
 to the air, the circulation of the must within the tank, &c. ; 
 third, the activity of the yeast cells, i.e. 9 the rapidity of 
 fermentation. 
 
 Percentage of Sugar. The amount of sugar in the must 
 varies from year to year in the same place with the same 
 varieties. In hot countries there is, other things being equal, 
 more sugar in the must than in cold countries. Some 
 varieties of grapes give more sugar than others ; and as high 
 alcoholic strength is, unfortunately, paid for as such by the 
 merchant, grape growers are apt to select those varieties 
 that produce the most sugar, and hence alcohol in the wine, 
 regardless of true quality. While this may be proper 
 enough in cold climates, it works great injury to the general 
 reputation of the wines of warmer countries, for alcohol is 
 
 * Diplome de VEcole d 1 Agriculture de Montpellier. 
 
APPENDIX. 239 
 
 not the only desideratum in wine. In hot climates there is 
 almost always, with the excess of sugar, a correspondingly 
 smaller amount of acid. It is, however, important to note 
 that very high sugar contents of must and low acid generally 
 go together, and that they are both, as a rule, undesirable. 
 
 Ex-cess of Neat. The amount of heat generated within 
 the fermenting tank is very great, being sufficient, theoreti- 
 cally, to raise above boiling point the whole of a must rich 
 in sugar. Practically, however, the heat is generated 
 gradually ; and much of it is carried off by the gas generated, 
 as well as through the walls of the vat, and from the surface 
 of the fermenting liquid ; otherwise fermentation beyond a 
 certain point would be impossible. This fact has taught 
 wine-makers in warm countries the necessity of a free circu- 
 lation of air in the fermenting room, unless that air is hotter 
 than the temperature of the fermenting mass. Hence the 
 benefit of the practice of fermenting in small packages with 
 thin walls : first, because of less actual amount or quantity 
 of heat (calories) generated ; and, second, because of the 
 facility with which this heat can be carried off, and thus the 
 equilibrium between the temperature of the fermenting mass 
 and the outside air be maintained. This has led many wine- 
 makers to have their tanks made of small diameter, of great 
 height, and of very thin material of -high conductivity, such 
 as thin enamelled iron. While this certainly enables the 
 operator to completely control the temperature, it has proved 
 far too expensive for general use. But, unquestionably, the 
 growing custom of using very large tanks is essentially bad 
 practice. 
 
 Activity of the Yeast. The third factor in the problem is 
 the activity of the yeast-cell. There are many circumstances 
 that modify this activity. First it must be remembered that 
 the yeasts are plants/ and that, in a general way, their 
 growth (activity) is modified by the same conditions that 
 affect the higher plants growing in the fields. Extremes 
 either of heat or cold are unfavorable to their maximum 
 development, Thus in cold climates the wine-maker keeps 
 a fire constantly burning in the fermenting-room, while in 
 hot countries all his energies are bent on reducing the 
 temperature to that most favorable for proper fermentation. 
 
 It is also noted that the higher plants have different 
 " optimum " temperatures ; for there are tropical plants, 
 plants of temperate regions, and plants that grow in the 
 arctic regions. It is the same, within certain limits, with 
 
240 WINE-MAKING IN HOT CLIMATES. 
 
 the yeast-plants. This variation is, as yet, but little known, 
 for it is within but a few years that serious attention has 
 been given to this branch of science so magnificently set 
 forth by Pasteur. Suffice it to say that something has been 
 done, and that the beer brewers have put these principles in 
 practice with eminent success. Now the yeast-plant of the 
 brewers splits up sugar into alcohol and carbonic acid gas, 
 just as the wine-yeasts do, and is influenced by exactly the 
 same conditions. 
 
 In th case of the seeds of the higher plants of all kinds, 
 activity does not begin until the proper temperature has 
 been reached. Should the temperature in spring rise slowly, 
 the growth of all plant life is correspondingly slow ; but so 
 surely as a sudden great rise in temperature takes place, 
 plant life will be intensified by it until, when excessive 
 temperatures are attained, it is either paralyzed temporarily 
 or the plant may die. 
 
 Similarly, if the grapes arrive at the fermenting tank 
 much heated, then we may look for a sudden violent 
 development of yeast-plants or fermentation. This is 
 unfavorable for several reasons : first, because the heat is 
 generated so rapidly that a due amount cannot be carried 
 off in time by conduction, and high temperature is reached 
 very quickly, whereby the yeast may be paralyzed or killed. 
 But more than this ; within certain limits each degree of 
 sugar in the ' must means a corresponding amount of heat 
 generated in the tank. Now, if fermentation starts in at a 
 low temperature, say T)6 degrees F., the generation of heat 
 will be slow at first, and the rate of fermentation will be 
 correspondingly slow, and apparently less heat will be 
 generated than if started at a higher temperature ; because 
 much is lost by conduction, although the amount is actually 
 the same. The starting point was so low that the heat that 
 was not carried off by conduction is not sufficient, when 
 added to the initial temperature, to carry it to the killing 
 point. Let the initial point be 75 degrees F., as is frequently 
 the case, then the extra heat added by the greater rapidity 
 of fermentation will carry the temperature, without doubt, 
 to the death limit. Hence the many efforts made to get the 
 grapes into the tank in a cool state. Wherever this can be 
 done, the fermentation usually goes through well ; but 
 practically this is possible only on a small scale. Hence in 
 a warm climate like that of California the initial tempera- 
 ture of the must is always over 60 degrees F., and in some 
 
APPENDIX. 241 
 
 cases over 76 degrees F. The danger arising from over- 
 heating is, therefore, naturally to be expected. Actually, 
 at all the wineries of this State, over-heating does occur 
 almost continually, and great financial losses result there- 
 from. 
 
 Nourishment. But aside from the general climatic con- 
 ditions, all plants are profoundly modified in their growth 
 by the nourishment they receive from the soil in which they 
 grow. Aside from the sugar required to nourish the yeast- 
 plant, one of the most important factors in the problem of 
 its growth is the acid. There are other factors, but these 
 are not essential in this connexion. Now, just as there are 
 plants that will grow in alkali soil, and others that will 
 not, so there are yeast plants that will thrive in a non- 
 acid medium, and others that will not. 
 
 Diseases of Wine. This brings us to the plants that 
 cause the diseases of wine ; for it should be understood 
 once for all, that a " spoilt " wine is spoiled not spon- 
 .taneously, but by the growing in it of some minute plant 
 which uses the substances of the wine to nourish itself, 
 and to produce both its natural products, most of which 
 are foreign to normal wine, and unpalatable besides. Thus 
 the bacteria of putrefaction destroy otherwise edible meat 
 and render it unfit for human consumption. In the same 
 manner all diseased or " spoilt " wines have been rendered 
 so by some plant of a lower order than the yeast-plant 
 that gave it its quality. 
 
 Importance of Proper Temperature. Returning to the 
 question of temperature, it has been established beyond the 
 possibility of rational dispute that, in the majority of cases, 
 those temperatures most favorable to the wine-yeast plant 
 are unfavorable for the development and growth of disease- 
 plants or bacteria, and vice versa. 
 
 In a general way we may say that the wine-yeast is a 
 plant of the temperate zone, while the disease bacilli are 
 plants of the tropics ; the one requiring moderate heat 
 for its normal growth, and the other requiring a much 
 higher temperature in order to grow and act at all. This 
 explains the practice of keeping wine in cool cellars. This 
 is a very important point. High temperatures are very 
 unfavorable for normal wine-yeast, and very favorable to 
 the bacteria which cause wines to spoil. After the limit 
 of temperature favorable to the yeast-plant has been passed, 
 the quality of the wine deteriorates with great rapidity : 
 
242 WINE-MAKING IN HOT CLIMATES. 
 
 not necessarily because the wine-yeast is actually killed, 
 nor that its action has ceased altogether ; but that its 
 activity has been checked, and that the harmful bacteria 
 have begun their work ; producing, not alcohol, carbonic 
 acid gas, glycerine, &c., but their own characteristic pro- 
 ducts, such as mannite, acetic, lactic, and butyric acids, 
 &c., &c. 
 
 Paralysis and Death of Yeast-plants. The degree of 
 paralysis of the yeast-plant depends upon the temperature 
 and composition of the must. The absolute point of 
 temperature at which paralysis or death will overtake the 
 yeast-plant cannot be fixed absolutely, as it depends upon 
 the variety of ferment or yeast-plant, as well as upon the 
 conditions in which it works best. For normal musts 
 with a normal yeast, the death point is generally from 
 98 to 100 degrees F. Some varieties of yeast (and 
 these are few) will stand more heat, most of them suffer- 
 ing greatly before this point is reached ; the must als3 
 should be of a composition naturally favorable to them. 
 Before this point is reached the bacteria begin to develop, 
 while the wine-yeast stops growth ; and the wine, if not 
 spoiled, is rendered of less value than it would have been 
 had the temperature remained lower. 
 
 Effect on Bouquet and Aroma. It should be noted in this 
 connexion that, with certain reservations, the general rule 
 is that the lower the temperature of fermentation the better 
 the aroma and bouquet of the wine. In other words, the 
 proper regulation of the temperature of the must during the 
 first or tumultuous fermentation means the production of a 
 wine richer in alcohol, of better keeping qualities, and better 
 quality throughout. 
 
 Use of Antiseptics and Antiferments. With this review 
 of the general principles governing fermentation, we come 
 to the practical lessons deducible therefrom. We have had 
 occasion to note the heavy annual loss to wine-makers from 
 " stuck tanks," resulting either in the total destruction of the 
 wine, or the partial loss of its market value. We have also 
 had occasion to listen to the criticisms of the purchasers of 
 Californian wine, both abroad and in this country ; and in 
 by far the greater number of cases the fault found was not 
 so much with the quality (for well-made Californian wine 
 compares favorably, grade for grade, with any in the world) 
 but in the unsoundness, i.e. the tendency to spoil on the 
 hands of the purchaser before reaching the consumer. This 
 
APPENDIX. 243 
 
 lias led to the use of antiseptics, " anti-ferments," that is 
 poisons which kill outright or paralyze, not only the wine- 
 yeast but all bacteria that might intervene, and in some 
 cases the consumer as well. The making of wine at high 
 temperatures is simply inviting the use of antiseptics; for, 
 as a matter of fact, unsound wine can only be marketed by 
 the use of some powerful agent, to keep the bacteria in check. 
 Few wine-makers realize the great harm done to the reputa- 
 tion of Californian wines by a few unscrupulous or ignorant 
 dealers who systematically buy up unsound wines, "doctor" 
 them, and ship them abroad. The sooner the use of anti- 
 septics of any kind (except pure wine alcohol) is stopped, 
 the better it will be for all concerned in viticulture. It is to 
 be regretted that there is no law enforced that punishes 
 those who use dangerous drugs in wine. 
 
 Stuck Tanks. A " stuck tank " is a very common occur- 
 rence at most ' all wineries in California, as well as in all 
 countries having similar climates. It means that the yeast 
 germs that convert the juice of the grape into wine have 
 suddenly ceased their normal action, and fermentation proper 
 has ceased, while bacterian activity has started up ; result- 
 ing either in the total or partial loss of the wine. One wine- 
 maker of this State told us that his loss from stuck tanks 
 amounted in a single season to 10,000 dollars ; and there are 
 but few who do not suffer to a certain extent from this 
 trouble. 
 
 As has been shown, the commonest cause of stuck tanks 
 is too high temperature. The trouble is not by any means 
 confined to California ; but is the curse of all wine-making 
 countries in the warmer parts of the world, viz., all 
 Southern Europe, North and South Africa, Australia, &c. 
 The wine-maker of these countries has been found to be less 
 self-complacent than his California brother, and has made 
 serious efforts to control the temperature of fermentation. 
 
 Methods of reducing Temperature. By some wine-makers 
 the amount of sugar was reduced by the addition of water. 
 This, in many cases proved of great service, but in others 
 it was not so; for the water also reduces the acid and the 
 body of the wine, and unless there be sufficient acid, nor- 
 mal fermentation does not take place, save under excep- 
 tional circumstances. Others tried to reduce the tempera- 
 ture of the wine by the addition of ice to the fermenting 
 tank. This had not only the same effect as the addition 
 of water but proved utterly impracticable in the case of 
 
244 WIXE-MAKING IN HOT CLIMATES. 
 
 red wine and is not economical. Some tried the use of 
 metal spiral coils plunged in the fermenting tank through 
 which cold water was passed. This proved successful in 
 the case of wine fermenting without skins or stems (white 
 wine); but was impracticable in 'all cases where the skins 
 and stems were left in the tank, owing to the impossi- 
 bility of sufficiently mixing the hot and cold parts of the 
 fermenting mass. Others tried metal tanks, but this was 
 found to be too expensive. 
 
 Again, some tried pumping the wine from the bottom 
 of the tank over into the top and allowing it to spread 
 out into a spray. This accomplished two results: it cooled 
 the wine slightly (but very slightly) and especially did it 
 revive the partially paralyzed yeast cells by giving them a 
 fresh supply of free oxygen. The fatal defect of this 
 practice was found to be the too great oxidation and 
 evaporation of the alcohol, which took place at high tem- 
 peratures, the wine becoming too highly charged with acetic 
 acid (vinegar-sour). Nevertheless, this pumping over of 
 the wine of stuck tanks, or tanks that threaten to stick, 
 is now widely practised all the world over, and in the case 
 of a sudden stopping of fermentation it is necessarily done 
 to supplement the addition of fresh must in active fermen- 
 tation used to finish the conversion of the sugar into 
 alcohol and carbonic acid gas. 
 
 Experiments at the University. Convinced of the neces- 
 sity of controlling the temperature of the fermentation of 
 wines in this State (just as the brewers do that of iheir 
 fermenting wort to a fraction of a degree, always getting 
 a product the value of which is known beforehand), the 
 Viticultural Staff of the College of Agriculture set about 
 to devise some practical method for attaining this end. 
 It was only after having completed the experiments with 
 the apparatus herewith described, that we received detailed 
 data of the European experiments with the refrigeration 
 of wine. We give below a complete description, first, of 
 the French apparatus; second, of the one first devised at the 
 Experiment Station; and, third, of the one modified as found 
 advisable after thorough trial. 
 
 Apparatus used in other Countries. Figure 21 (page 116) 
 represents one of the forms of the apparatus now used 
 throughout Northern Africa and Southern France. As will 
 be seen, it consists essentially of two columns, each made up 
 of nineteen thin, well-tinned, horizontal copper tubes. These 
 
APPENDIX. 245 
 
 tubes are 13 feet long by 1 inches in diameter. The total 
 length of the tubes through which the wine passes is thus 
 nearly 500 feet. These tubes are fitted into solid bronze 
 castings, closed by means of a bronze plate over a rubber 
 washer, with thumb-screws. The two columns are connected 
 by a tube (3 fig. 21) running diagonally from the top of one 
 column to the bottom of the other, so that the hot wine enter- 
 ing at the lower end (7 fig. 21) of the first column, and after 
 passing upwards and completing the circuit in this column, 
 passes to the bottom of the second column, from which again 
 it escapes at the top. Above the two columns of tubes is a 
 large metal water-box, having two rows of holes in the bottom 
 corresponding to the two columns, from which cold water is 
 allowed to drip as the warm wine is pumped through the 
 tubes. Under the apparatus is a metal box, which catches 
 the drip of warmed water. Each column of tubes has a 
 stop-cock (13), which allows rapid emptying of the wine 
 when pumping is stopped. The apparatus is, as before said, 
 now actually in use in other countries, and we are indebted 
 to the excellent report of Messrs. Miintz and Rousseaux in 
 La Revue de Viticulture for the results of their exhaustive 
 experiments conducted in France during the past season, 
 1896, as well as during the season of 1895. 
 
 The first defects that strike one in this apparatus is the 
 unwieldiness and expense, as well as the large amount of 
 labour required to force a IJ-in. stream of wine through 
 such a length of tubing at a working rate ; then the amount 
 of water used in cooling the wine must be very large, unless 
 the temperature of this water be considerably below that of 
 the wine. As in the case of the use of ice, it will do well 
 when all conditions are most favorable. 
 
 In a recent article, giving a resume" of the two seasons' 
 experiments, Messrs. Miintz and Rousseaux tell us that to 
 work the apparatus a gang of four men, working in relays, 
 is required to pump 40 hectolitres or 1,060 gallons per hour. 
 With a motor engine double this amount could be pumped 
 through, but the quantity of water needed in this case for 
 the proper cooling of the wine is enormous, amounting to 
 from one to one-and-a-half times the amount of wine passed 
 through ; or far more cold water than is generally to be had 
 at the average California winery. 
 
 The reduction of temperature was in some cases very 
 great, but depended altogether upon the rate of pumping, 
 
246 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 the amount of water dripping over the tubes, and the initial 
 temperature of this water. There was an average reduction, 
 however, of from 10 to 12 degrees F., but in some cases a 
 maximum of as much as 20 degrees when slow pumping was 
 practised. The cost of cooling the wine was, on an average, 
 one-thirteenth of one cent per gallon. 
 
 From the careful tests made by these eminent scientists, 
 the remarkable benefits of cooling the fermenting mass was 
 strikingly shown. In all cases a certain lot of the same 
 must was fermented in the usual way as a check to the 
 experiment, and in every case the cooled wine was sounder 
 and of far better quality. Microscopic examination showed 
 that the uncooled wine was teeming with harmful bacteria, 
 while the amount of unfermented sugar remaining was very 
 considerably more than in the case where the wine had been 
 cooled. The University experiments showed this as strikingly 
 as did those of Miintz and Rousseaux. 
 
 We give below a table taken from La Revue de Viticul- 
 ture, in which some of these results are set forth. Unfortu- 
 nately the recent disastrous fire at the Agricultural Building 
 at the University destroyed all the notes taken at each tank 
 cooled, so that we can but give the general results. These 
 results were, however, looked over but a few days before the 
 fire, and, being compared with those made in France by 
 Miintz with his apparatus, were found to be essentially in 
 accord, as appears from the data given below. We give 
 below the exact figures obtained by these observers. This 
 shows the matter to be not of something " theoretical " and 
 untried, but something that has been tried by several, and 
 proved to be a practical success. 
 
 The experiments were made in the Rousillon district of 
 France, near the Eastern Pyrenees, during the season of 
 1896, with Carignane grapes. 
 
 . 
 
 Maximum tempera- 
 ture of the must 
 during fermentation. 
 
 Alcohol per cent. 
 
 Unfermented 
 Sugar. 
 
 Cooled Wine 
 
 5 5 5 
 
 Uncooled Wine .. 
 
 96 (F.) 
 96-8 
 99-5 
 102-2 
 104-0 
 
 11-00 
 
 11-45 
 11-50 
 10-20 
 10-10 
 
 59 
 65 
 2-60 
 3-30 
 
APPENDIX. 247 
 
 It will be recollected that experiments made by Prof. 
 Hilgard at the University, in 1887, gave almost precisely 
 similar results as to alcohol percentage when hot and cool 
 fermentations were compared. (See Report of the College 
 of Agriculture on Methods of Fermentation of 188687, 
 p. 28.) 
 
 The effects of high temperature on the composition of the 
 wine may be further illustrated by some other analytical 
 results from the French experimenters, Miintz and Rous- 
 seaux, who found in 1895 that a wine which had attained a 
 maximum temperature of 98'5 degrees F., during fermenta- 
 tion showed on analysis '066 per cent, of ammonia, while 
 another wine made from the same lot of grapes, which 
 attained a maximum of 104 degrees, showed -60 per cent. 
 Similar results were obtained in 1896, when maxima tem- 
 peratures of 94 degrees and 104 degrees gave '03 per cent, 
 and -22 per cent, of ammonia respectively. It is clear, 
 therefore, that serious chemical differences and defects are 
 produced in the wine by high temperature fermentations 
 apart from the swarms of disease bacteria which are always 
 present in such wine. Of the wines made by Miintz and 
 Rousseaux in their 1896 experiments, those that were not 
 cooled threaten to spoil already ; while those that were 
 cooled are in perfect condition. 
 
 EXPERIMENTS MADE BY THE UNIVERSITY AT NATOMA, 
 SACRAMENTO COUNTY, AND AT EVERGREEN, SANTA 
 CLARA COUNTY. 
 
 Apparatus used. The results of Miintz and Rousseaux 
 were amply confirmed by the investigations undertaken by 
 the Viticultural Staff during the season of 1896 at the 
 Natorna Vineyard in Sacramento County, and at Mr. 
 Wehner's at Evergreen, near San Jose. The apparatus 
 used by us differed greatly from that used by Miintz and 
 Rousseaux, and the many others abroad who practised 
 refrigeration during fermentation at the same time. 
 
 Not being able to avail ourselves of the detail of the 
 numerous experiments undertaken along the same lines 
 abroad during the past few years, we had to construct our 
 apparatus independently upon what we considered the most 
 promising lines ; fortunately, as it turned out, committing 
 few mistakes and obtaining results that show our system 
 to be far superior to any thus far proposed for California 
 
248 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 conditions. However, experience has shown ns the desirability 
 of certain changes and modifications as hereinafter shown, 
 especially as mechanical power for pumping and crushing is 
 available at nearly all wineries of this State. 
 
 The apparatus 
 shown in figure 2 
 is the one de- 
 signed and used 
 by us in the ex- 
 periments. It 
 will be observed 
 that in so far as 
 the pumping of 
 the heated wine 
 through tinned 
 copper tubes 
 goes, the princi- 
 ples are identical 
 with those of the 
 French appara- 
 tus. The method 
 of pumping is 
 the same as is 
 in practice at 
 wineries for 
 drawing off the 
 newly fermented 
 wine from the 
 fermenting tank. 
 The wine is 
 drawn off from 
 the bottom of 
 the tank, and 
 strained through 
 a sieve into a 
 tub, from which 
 it is pumped 
 through the ap- 
 paratus into the 
 top of the tank 
 again. In other 
 
 respects there are important differences ; thus, instead of two 
 columns consisting of 498 lineal feet of tubing, our apparatus 
 consisted of a single column of only 42 feet of tubing. The 
 
APPENDIX. 240 
 
 tinned copper tubing instead of being perfectly round is very 
 much flattened, thereby giving greater cooling surface to the 
 same volume of wine, a material improvement on the French 
 system of round tubes. It consists of fourteen pieces 3 feet 
 long and 4 inches broad by 1^- inches deep. These tubes are 
 fitted into bronze castings, which are closed by plates fitting 
 over rubber washers, and fastened by thumb-screws, thus 
 allowing the tubes to be readily cleaned in cases of obstruc- 
 tions that might occur in the pumping through of the 
 muddy, partly-fermented must. 
 
 METHODS OF COOLING. 
 
 Water-box. In our first experiments the whole apparatus, 
 that is to say the column of tubes, was fitted into a box, tin- 
 lined and filled with water. A constant supply of fresh water 
 entered the box at the bottom, escaping from the top, while 
 the wine entered the top of the apparatus and escaped at the 
 bottom, in order that the coldest wine should come in con- 
 tact with the coldest water, and vice versd. It is well known 
 that this arrangement will give the greatest amount of 
 cooling effect. 
 
 It was found that by the use of a very large quantity of 
 water the wine could be sufficiently cooled, but the excessive 
 amount of water thus required caused us to abandon this 
 system. In special cases, where an unlimited water supply 
 is to be had without too great expense, this system should 
 be adopted, for though the cost of water-box and installation 
 will about offset the cost of the blower and canvas sleeve, 
 hereinafter described, it has the advantage of doing away 
 with the necessity of the command of power. In case this 
 system is adopted, it is well to use a greater length of tubing 
 than would be required where the spray and the air current 
 are used. Roughly speaking, the amount of water used in 
 this case should be from 1^ to 2J times the volume of wine 
 pumped through the apparatus. 
 
 Drip, Spray, and Blast. Instead of depending upon the 
 simple dripping of the water over the tubes to effect the 
 reduction of temperature of the warm wine, a great saving of 
 tubing, as well as labour in pumping, was found to be 
 effected by the use of a fine spray of water carried by a strong 
 blast of air, thus combining the effects of cold water and 
 evaporation. The quick evaporation brought about by the 
 dry air prevailing at our vintage season, when mingled with 
 
250 WINE-MAKING IN HOT CLIMATES. 
 
 a fine spray, produces a cooling effect far in excess of what 
 could be obtained from the ordinary water at the wineries 
 alone. This is important, for at many of the wineries the 
 water available is very warm and the difference between the 
 temperature of the water and the wine to be cooled is so 
 slight that it would be impossible to effect a proper amount 
 of cooling, unless enormous volumes of water were used. 
 
 The proper proportions between the air blast and the 
 amount of water sprayed is of the utmost importance. It is 
 readily understood that a weak blast with a large amount of 
 coarsely-sprayed water would leave the temperature of the 
 water almost unchanged when it reaches the cooler, and 
 would, therefore, amount to little more than the dripping- 
 practised in the French apparatus ; while if the blast be in 
 excess and the water deficient, the amount of water carried 
 may not be sufficient to utilize the evaporative power of the 
 blast, nor to thoroughly wet the tubes. Again, to insure 
 the maximum cooling from evaporation, the spray should be 
 so fine that within the short distance from the nozzle to the 
 tubes the air may become fully saturated, and both cooled 
 to the fullest extent. Of course, the heavier the blast the 
 more water spray can be carried and cooled by it. To pro- 
 duce the requisite fineness of spray, an adequate water 
 pressure is necessary. 
 
 Another factor of the utmost importance is the dryness, 
 or what is technically called the " relative humidity " of the 
 air used. During the vintage season this is frequently as 
 low as 33 per cent, outside of the ivinery, and the intense 
 evaporating effect producible under such conditions should 
 be utilized by connecting the intake with the outer air. This, 
 of course, can be done either by a canvas tube stretched by 
 hoops, or by a board flume. 
 
 When, as may happen near the coast, the moist condition 
 of the air is unfavorable to strong evaporation, the water 
 temperature, on the contrary, is frequently itself so low that 
 an energetic spray without a blast may suffice to do the 
 necessary amount of cooling. 
 
 It will be noted, therefore, that the best conditions for 
 cooling will vary, not only in different localities, but on 
 different days, and according to the prevailing wind ; so that 
 it is impossible to prescribe the exact strength of blast or 
 quantity of spray that should be used. But a few experi- 
 ments will determine the best practice in any given locality. 
 
APPENDIX. 251 
 
 In our experiments the blast of air was generated by 
 means of an 18-in. " double " (8-wing) blower, or " exhaust- 
 ikn " reversed. The water escaped from a battery of three 
 Vermorel nozzles placed immediately in front of the blower. 
 
 A conical canvas sleeve attached to the outlet of the 
 blower and 5 J feet away to the circumference of the cooler- 
 frame prevents the loss of blast and spray. 
 
 The "double" 18-in. blower requires under ordinary 
 circumstances less than one-half horse-power to run it at a 
 rate of 1,000 revolutions per minute, and thus, with a free 
 supply, will pass 3,000 cubic feet per minute through it. 
 The 24-in. " double " blower requires about the same horse- 
 power to run it, but requires only 900 revolutions per minute 
 to send through 5,000 cubic feet in the same time. It should 
 be remembered that the best efficiency of every blower is 
 limited to a definite velocity of revolution. The figures 
 above given refer to the most favorable velocities for the sizes 
 mentioned. The one costs 40 dollars (less discount) while 
 the latter costs 50 dollars. In order that the apparatus may 
 be available at small-scale wineries, where no steam is used, 
 it may be well to state that a small gas engine, run with 
 common " distillate " and giving 2 J horse-power, can be 
 had for 187 dollars (less discount). The cost of running 
 such a motor is 1 cent per horse-power per hour; a trifling 
 expense, especially as the motor, once started, will run itself, 
 so that one man can attend to the pumping of the wine and 
 the running of the engine at the same time. Indeed, with a 
 little fitting, such an engine could be made to do all the 
 pumping in the cellar, and there are no labourers who will 
 do 1 horse-power of work for a cent an hour. 
 
 While the French apparatus was movable, ours was of 
 necessity fixed, but with one man at the pump at Mr. 
 Wehner's place it was found that he could pump from the 
 most distant tank at the rate of 1,000 gallons per hour, in 
 some cases as much as 1,400 gallons. At this rate a reduc- 
 tion of temperature of from 10 to 13 degrees was obtained in 
 the wine. The temperature was taken at the point where 
 the wine left the tank and again where it re-entered the 
 tank after having passed through the cooler. 
 
 Precautions. We found that the much-feared deposit of 
 cream of tartar on the inside of the tubes was very slight 
 indeed. It would seem that while warm wine on cooling 
 will deposit cream of tartar on the lining of the vessel, wine 
 
 10649. R 
 
252 WINE-MAKING IN HOT CLIMATES. 
 
 constantly in motion (as when being pumped) will not 
 deposit much. Even after long use it was found that the 
 thin coating of cream of tartar on the inside of the tubes 
 could be removed by pumping the apparatus full of water 
 and leaving it over night after a few barrels had been pumped 
 through. The apparatus should be flushed out at least once 
 in twenty-four hours, for the deposit of cream of tartar, be 
 it ever so slight, interferes greatly with the conduction of 
 heat, and anything that has this effect must be carefully 
 avoided. Even the surface of the tubes should be polished 
 once a day with ashes or lye, for there forms on the surface 
 after a day's use a " greasy " film, due to the lubricant neces- 
 sarily used in the blower, which not only interferes with the 
 conduction of heat, but causes the water to run in streaks 
 over the surface instead of spreading over it, much cooling 
 surface being thus lost. 
 
 The seeds and skins should be kept out as well as possible 
 from the pump and consequently from the apparatus. By 
 exercising due precaution in this regard, we did not have to 
 clean the apparatus from this cause once during the entire 
 trial. 
 
 Control of Temperature. We found, as did Miintz and 
 Rousseaux, that when the wine passed 100 degrees F. cooling 
 was useless, for the ferments or yeasts were too badly 
 injured -to be revived. Thus a tank at Natoma (where the 
 conditions were unfavorable on account of hot weather) was 
 fermented with some Algerian yeast, and was allowed to go as 
 high as 104 degrees F. The tank "stuck" before fermen- 
 tation was finished, and it could not be revived by cooling. 
 
 Miintz and Rousseaux state that if a tank is cooled before 
 the temperature reaches the danger limit there need be no 
 fear that a subsequent rise to this limit will take place. We 
 found at Mr. Wehner's that under the conditions existing, 
 when the temperature in the tank reached 88 degrees F., if we 
 pumped about one-half or two-thirds of the contents of the 
 tank through the cooler, nothing disastrous ever happened, 
 although the fermentation kept right on and the rise in 
 temperature continued, yet it seemed that a sufficient amount 
 of heat (calories) had been removed from the fermenting 
 mass to enable it to complete fermentation without reaching 
 the danger point. This favorable result, however, must 
 largely depend upon special conditions, and should not be 
 relied upon so as to relax vigilance. 
 
APPENDIX. 253 
 
 Considering; the fact that low temperature fermentation 
 gives a wine of a different composition from that fermented 
 at high temperature, and leaving for a moment the killing 
 of the yeast out of the question, it is evident that it would 
 pay to keep the temperature constantly below the danger 
 limit on account of the superior quality of the resulting 
 wine. 
 
 It might not pay in ordinary cases to go to this expense 
 for quality alone, yet if extra fine wine is to be made, extra 
 care must be bestowed upon it. 
 
 Aeration of the Wine. It was deemed advisable to aerate 
 the wine whenever it was pumped over. In order to accom- 
 plish this, and at the same time to prevent the cooled wine 
 from forming a channel in the cap and passing at once to 
 the bottom and thus leaving the warmer wine at the top, we 
 caused the wine to escape from the end of the hose in a 
 fan-like jet, the direction of which was, from time to time, so 
 changed as to reach all parts of the cap during the cooling. 
 In this way the cap was very greatly cooled, which is 
 important, as it is the hottest part of the fermenting mass 
 in a tank. 
 
 In all cases where the cooling took place at or about 
 88 degrees F., the tank " went dry " perfectly well, and the 
 resulting wine was drier and far clearer than in case of the 
 wine not cooled and aerated. This was especially noticeable 
 in cases where pure cultures of yeast were used, especially 
 some of the foreign varieties. 
 
 In some cases we tried the use of an extra empty tank 
 into which the cooled wine from the first tank pumped was 
 put, and the cooled wine from subsequent tanks was pumped 
 into the first tank. At the end of a certain time the wine 
 first cooled was pumped into the last tank. In this way one 
 avoids cooling the same wine or part of it twice, but an 
 extra pumping is thus necessitated. The avoidance of cooling 
 wine that has just been cooled and pumped back to the top 
 of the tank is certainly an important problem, that must be 
 solved by each wine-maker according to circumstances. We 
 would suggest that a storage tank, at a greater elevation 
 than the fermenting tank, be used as a common receptacle 
 for all cooled wine. As soon as a sufficient amount 
 of wine in any given tank has been cooled, it can be 
 returned by gravity, and thus all danger of wasting energy 
 by pumping the same wine twice through the cooler can 
 
 R 2 
 
254 WINE-MAKING IX HOT CLIMATES. 
 
 be avoided. It is true that there will be an extra amount 
 of labour required to force the cooled wine to a greater 
 level than that of the fermenting tank. 
 
 Faults of the Apparatus. It was found that with our 
 first apparatus we had made the mistake of placing the tubes 
 too far apart (2J inches), losing thereby a very considerable 
 amount of air and spray. This we had to remedy for the 
 time by filling up the space with 2-in. slats ; but this, of 
 course, caused a great waste of cooling effect. We, there- 
 fore, in our modified apparatus, recommend that the tubes 
 be placed 1 inch apart, which is the practical limit for the 
 successful soldering of the tubes into the castings, more 
 especially when the tubes are of such greater width as we 
 now find desirable. The horizontal position, moreover, will 
 always prove a source of waste, on account of allowing too 
 ready a passage for the current of air and spray. It was 
 also found that for large scale operations the cooling capacity 
 of the apparatus was not adequate. 
 
 THE NEW APPARATUS. 
 
 In the construction of the new apparatus the need of 
 greater capacity was first considered. The lengthening of 
 the tubes, as in the French model, renders it very cumbersome ; 
 and it, therefore, seemed preferable to retain the same length 
 of tubes, but to give them an increased cooling surface by 
 enlarging their dimensions to 5^ inches x 1-J inches, and to use 
 two batteries or columns placed one behind the other. This 
 arrangement would serve in any case to utilize better the 
 cooling current, which must always waste through a single 
 system of tubes, however placed. Moreover, the increased 
 cooling surface obtained by widening the tubes does not 
 involve an increase of friction, as would a lengthening of 
 tubes, to attain the same purpose. 
 
 Another modification deemed wise is to have the extremi- 
 ties of the tubes closed by a single bronze casting instead of 
 separate castings for each pair of tubes. These castings 
 are fastened by thumb-screws over rubber washers, as in 
 the case of the first machine. The advantages are that it 
 not only requires fewer thumb-screws (and hence allows 
 greater rapidity in cleaning), but also that the solidity of 
 the whole apparatus is greatly enhanced, and the necessity 
 for an extra frame is done awav with. We found that with 
 
APPENDIX. 
 
 255 
 
 the great number of small castings it was difficult to keep 
 any frame from " giving " a little. (See Fig. 3.) 
 
 1 1 
 
 
 Relative Position of the Sets of Tubes In order to 
 determine as nearly as possible the various conditions need- 
 ful to secure the best results, two sets of tubes of twelve 
 each were placed in a convenient frame, and so suspended 
 
256 WINE-MAKING IN HOT CLIMATES. 
 
 on chains that both their distance and their relative positions 
 could be readily changed at will. While this would not 
 enable us to determine exactly all the best conditions in the 
 completed arrangement, it would at least enable us to avoid 
 such mistakes as rendered the first apparatus to some 
 extent unsatisfactory. 
 
 It soon became apparent that so long as the tubes in the 
 two sets were placed parallel to each other, whether 
 horizontally, or inclined upwards or downwards, even when 
 arranged as closely as practically possible, and so as to 
 break joint, there was a great waste of spray, and therefore 
 of cooling power, in the rear or the second column. The 
 obvious remedy was to place them at an angle to each other, 
 so that the current could be considerably checked and its 
 direction completely changed before being allowed to emerge 
 at the rear end of the apparatus. It remained to be deter- 
 mined whether the relative inclinations should be in the 
 form of a V or of an A, and what the angle of the inclina- 
 tion should be. It was evidently not desirable to make this 
 angle steeper than necessary to accomplish the purpose. 
 
 Points observed. In making the experiments the points 
 observed were : First, the absence of any considerable waste 
 of spray beyond the second column ; second, the approxi- 
 mate equality of the drip of water from both sets ; third, 
 the diminution of temperature obtainable with varying 
 strength of spray and blast. We could thus as nearly as 
 possible estimate the results likely to be obtained by the 
 apparatus when completed. In all experiments so far 
 made the two sets were placed as near together as practi- 
 cally possible. As to the first point it was found that the 
 least waste of spray occurred when the tubes were placed 
 1 inch apart in the inverted Y (A) position, and that for 
 this purpose an angle of 30 degrees was sufficient. 
 
 Second, it was further found that under these conditions 
 the drip from the two sets of tubes was most nearly equalized, 
 and that their entire surfaces remained well wetted. 
 
 As regards the third point, it was found that in the 
 space between the two sets the temperature was mainly 
 governed by the strength of the blast and the amount 
 and kind of spray used. In this respect our preliminary 
 experiments could give only comparative values, since the 
 
APPENDIX. 257 
 
 saturation of the air at Berkeley at the time was between 
 75 and 80 per cent., and the air temperature varying but 
 slightly above and below 60 degrees F. 
 
 Air Blast and Spray. No mechanical power being avail- 
 able at the time at Berkeley, we had to restrict ourselves in 
 the use of the blower to such a velocity as could be obtained 
 by the power of two men, which was between 700 and 750 
 revolutions per minute, obtaining probably about two-thirds 
 to three-quarters of the effect of the blower, or about 2,000 
 or 2,500 cubic feet per minute. 
 
 It was quickly noted that, as transmitted through the 
 pyramidal canvas sleeve directly, the distribution of the 
 wind over the surface of the tubes was very unequal, being 
 very strong at the circumference, and almost null in the 
 middle, on account of the centrifugal action of the blower. 
 This inequality was effectually done away with by the inter- 
 position between the blower and the pyramidal sleeve of a 
 cylindrical sleeve 3J feet long. 
 
 As regards the spray, a comparison of the reduction of 
 temperatures obtained with the rather coarse spray here- 
 tofore employed, with that obtained from a standard cyclone 
 nozzle yielding very fine spray, showed that the latter was 
 by far the most efficacious, besides which it permits of a 
 shortening of the pyramidal portion of the sleeve, on account 
 of the rapidity with which evaporation can take place. To 
 attain this end, however, it is necessary that the pressure 
 should be sufficiently high ; that is, nearly such as is 
 obtained with spray pumps not less. Manifestly the coarse 
 spray carried with it too much of the original high tem- 
 perature of the water. It was also found, however, that a 
 single nozzle of this kind does not yield a sufficiently large 
 quantity of water, and that, therefore, a combination or 
 battery of such nozzles should be used, varying in number 
 according to the water pressure and the strength of blast at 
 command. In our apparatus we have adopted five as pro- 
 bably sufficient. 
 
 It is easy to so arrange the battery of nozzles as to 
 conform to the flare of the pyramidal sleeve, in order not 
 to waste the spray upon the canvas on the one hand, nor 
 to leave part of the space unutilized on the other. 
 
 Beneath the apparatus should be placed a shallow box 
 to catch the drip, which should be drained off through a 
 pipe or trough. A screen may be placed in the rear of 
 
258 WINE-MAKING IN HOT CLIMATES. 
 
 the apparatus to catch the spray that has passed through, 
 and may be of boards, sacks, or any thing that is con- 
 venient. If the apparatus be placed facing a door or 
 window, no screen is necessary. The current of air in itself 
 is not objectionable in a hot winery. The drawback to the 
 free circulation of the current of air and spray is that the 
 workmen working immediately in front of it after coming 
 from some hot part of the cellar are in danger of contracting 
 colds, or even pneumonia. 
 
 Conclusions. Accepting, then, the fact that in California 
 the tendency is to ferment at high temperatures, on account 
 of the initial as well as the air temperatures being higher 
 than in cooler countries, such as the Medoc, Burgundy, the 
 Rhine, Champagne, &c., and also the fact that in this State 
 we use exceptionally large fermenting tanks, and that our 
 musts are, as a rule,' very high in sugar, and, in many cases, 
 low in acid, the simple question is Shall we not attempt 
 to overcome these natural defects of our climate, and con- 
 trol fermentation, just as wine-makers of other countries do 
 under similar circumstances, and as the brewers have long 
 done under all circumstances ? 
 
 Competition is now so keen that if we would succeed we 
 must place on the market a wine that is equal, if not superior 
 to that of other countries. Under favorable conditions we 
 produce a wine that is equal to any in the world, but under 
 unfavorable conditions we make wines that are distinctly 
 inferior. 
 
 It is the custom at all the wineries of the State, in case of 
 the tank threatening to " sick," to pump the wine from 
 the bottom over the top, at the same time aerating it by 
 causing it to fall in a spray. Should the cooling apparatus 
 be used in connexion with this procedure, there would be 
 no extra cost beyond the original expense of the apparatus, 
 which will last indefinitely with proper care. 
 
 An apparatus such as we recommend will cost very little 
 compared with the enormous saving that can be effected in a 
 single unfavorable season. To provide several for use at a 
 large winery should not cost over 1,000 dollars, while for a 
 winery of ordinary size an apparatus capable of reducing 
 the temperature of the wine a minimum of 10 degrees at the 
 rate of 1,000 gallons per hour, would cost far less. Messrs. 
 Miintz and Rousseaux found that the cost of cooling wine in 
 France with their cumbersome apparatus was one-thirteenth 
 
APPENDIX. 259 
 
 of a cent per gallon. This includes four men at 70 cents 
 per day for pumping, and the wear and tear, interest on the 
 original cost of the apparatus, and all possible extra 
 expenses. It would not cost much over one-twelfth of a 
 cent per gallon in this country, even if we had to buy a 
 200-dollar motor (2^ h.p.) in addition to the apparatus 
 itself. It need not cost any more than this, for the motor 
 takes care of itself when once started, and any extra horse- 
 power could be used to advantage in pumping wine from one 
 tank to another. 
 
 In conclusion, we wish to express the sincere thanks of the 
 University to those who helped us with suggestions, money, 
 and material. 
 
 Messrs. Toulouse and Delorieux, of 622 Commercial-street, 
 San Francisco, constructed the apparatus according to our 
 designs, and it is due in no small degree to the extra time 
 and trouble bestowed by them tipon its construction and 
 modifications that the experiments proved successful. 
 
 Mr. D. M. Doub, of 137 First-street, San Francisco, came 
 forward in the most public-spirited manner, loaning us 
 several of the " blowers " and " exhaust-fans " needed. But 
 for such liberality the experiments could not have been 
 undertaken '. 
 
 The Pelton Water-wheel Co. also helped us not only with 
 the loan of machinery, but also by making for us on the 
 shortest possible notice such alterations as were suddenly 
 found necessary. 
 
 Mr. J. Henshaw Ward provided for our exclusive use at 
 the Natoma Vineyard 150-00 dollars worth of the best wine 
 hose, not otherwise obtainable. 
 
 Mr. J. H. Wheeler and Mr. J. Rennie, the lessees of the 
 Natoma Vineyard, allowed us to use part of the vintage and 
 cellar. 
 
 To Mr. Wm. Wehner, of Evergreen, we are especially 
 indebted, not only for the use of the cellar, vintage, 
 labourers, &c., but for the hospitality and attention he 
 bestowed upon us. The kindness and assistance we received 
 at his hands was exceptional. 
 
 Descriptions of the apparatus used abroad are given along- 
 side of the form we have devised, so that the wine-maker 
 may choose between them. 
 
 All that we desire is that some kind of effort shall be 
 made to control temperatures, be it the use of ice, water, 
 
260 WINE-MAKING IN HOT CLIMATES. 
 
 air, or anything else ; for it is certain that if the tempera- 
 ture is controlled there will be an improvement of from 10 
 to 1 00 per cent, in the quality of Californian wine. 
 
 The Viticultural Staff of the College of Agriculture will 
 cheerfully confer and advise with any persons interested in 
 this subject, and assistance in the construction or working of 
 coolers of any sort will be given. While we think that our 
 apparatus is better than any of the rest, all that we desire 
 is that there be some sort of cooling apparatus used, and 
 if our efforts contribute to the attainment of this end we 
 will be satisfied. 
 
APPENDIX. 261 
 
 THE METRIC SYSTEM. 
 
 MEASURE. 
 
 The Metric System takes for its basis the distance froni 
 the Equator to the Pole, dividing this into ten million parts. 
 One such part is a metre. The words denoting multiples 
 of the Metric standards are derived from the Greek, and 
 those denoting divisions, from the Latin, thus : 
 
 10 metres equal one decametre. 
 100 hectometre. 
 
 1,000 ,, kilometre. 
 
 10,000 myriametre. 
 
 T V of a metre equals one decimetre. 
 T <5- centimetre. 
 
 Tihm millimetre. 
 
 WEIGHT. 
 
 The weight of one cubic centimetre of water at 4C. is the 
 standard, and is called a gramme. 
 
 10 grammes equal one decagramme. 
 100 hectogramme. 
 
 1,000 kilogramme. 
 
 T V decigramme. 
 
 centigramme. 
 
 milligramme. 
 
 FLUID MEASURE. 
 
 The volume of a cubic decimetre is the standard, and is 
 called a litre. 
 
 1 00 litres equal one hectolitre. 
 ^ decilitre. 
 T U centilitre. 
 lAo milhhtre. 
 
 The hectolitre is the wholesale standard for wine. One 
 hectolitre of water weighs 100 kilos. 
 
262 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 THE METRIC AND BRITISH SYSTEMS. 
 METRIC MEASUKES. 
 
 One metre 
 
 = 39-37079 inches. 
 
 One decimetre = 3'937 
 
 5 
 
 One centimetre = 0'3937 
 
 One millimetre = 0-0394 
 
 Millimetres = Inches. 
 
 Centimetres Inches. 
 
 Millimetres. Inches. 
 
 Centimetres. Inches. 
 
 Centimetres. Inches. 
 
 1 = 0-039 
 
 1 = 0-394 
 
 10 = 3-94 
 
 2 = 0-079 
 
 2 = 0-787 
 
 20 - 7-87 
 
 3 = 0-118 
 
 3 = 1-181 
 
 30 i= 11-81 
 
 4 = 0-157 
 
 4 1*575 
 
 40 rz 15-75 
 
 5 = 0-197 
 
 5 - 1-969 
 
 50 zr 19-69 
 
 6 = 0-236 
 
 6 - 2-362 
 
 60 - 23-62 
 
 7 = 0-270 
 
 7 - 2-756 
 
 70 - 27-56 
 
 8 = 0-315 
 
 8 = 3-150 
 
 80 zz 31-50 
 
 9 - 0-354 
 
 9 = 3-543 
 
 90 = 35-43 
 
 METRES = FEET. 
 
 Metres. ft. in. Metres. ft. in. Metres. ft. yds. 
 
 1 - 3 3g 
 
 10 = 32 10 
 
 100 = 328 = 109 
 
 2 = 6 6J 
 
 20 - 65 7 
 
 200 = 656 = 219 
 
 3 = 9 10 
 
 30 = 98 5 300 - 984 = 328 
 
 4 = 13 li 
 
 40 = 131 3 400 = 1,312 - 437 
 
 5 = 16 r> 
 
 50 - 164 500 - 1,640 = 547 
 
 6 = 19 8 
 
 60 - 197 600 - 1,968 = 656 
 
 7 = 22 11J 
 
 70 - 230 
 
 TOO -2,297 - 766 
 
 8 = 26 3 
 
 80 - 262 800 = 2,625 = 875 
 
 9 = 29 6J 
 
 90 - 295 900 - 2,953 = 984 
 
ATTEND IX. 
 
 263 
 
 SQUARE METRES = SQUARE FEET SQUARE YARDS. 
 
 Square metres. 
 
 0929 = 
 1 = 
 2 = 
 3 = 
 4 = 
 5 
 6 = 
 
 (< 
 
 / 
 8 = 
 9 = 
 9-29 = 
 10 = 
 20 = 
 50 = 
 
 Square feet. 
 1 
 
 10-76 
 21-53 
 32-29 
 43-06 
 53-82 
 64-59 
 75*35 
 86-11 
 96-88 
 100 
 107-64 
 215-29 
 538-21 
 
 
 
 Square yards. 
 
 1-196 
 2-39 
 3-59 
 
 4-78 
 5.98 . 
 7-18 
 8-37 
 9-57 
 10-76 
 10-76 
 11-96 
 23-92 
 59-80 
 
 92-90 
 
 zz 
 
 1,000 
 
 
 
 59-80 
 
 100 
 
 zr 
 
 1,076-43 
 
 
 
 119-60 
 
 500 
 
 
 
 5,382-15 
 
 
 
 598-02 
 
 1,000 
 
 == 
 
 10,764-30 
 
 ;= 
 
 1,196-03 
 
 Square feet. 
 
 
 Square yards. 
 
 
 Square metres. 
 
 9 
 
 
 
 1 
 
 
 
 84 
 
 10 
 
 
 
 1 
 
 
 
 929 
 
 18 
 
 
 
 2 
 
 
 
 1-67 
 
 27 
 
 
 
 3 
 
 
 
 2-51 
 
 36 
 
 
 
 4 
 
 
 
 3-34 
 
 45 
 
 
 
 5 
 
 
 
 4-18 
 
 54 
 
 - 
 
 6 
 
 
 
 5-02 
 
 63 
 
 
 
 7 
 
 
 
 5-85 
 
 72 
 
 
 
 8 
 
 
 
 6-69 
 
 81 
 
 
 
 9 
 
 
 
 7-52 
 
 90 
 
 
 
 10 
 
 
 
 8-36 
 
 100 
 
 - 
 
 10 
 
 
 
 9-29 
 
 180 
 
 - 
 
 20 
 
 
 
 16-72 
 
 450 
 
 
 
 50 
 
 
 
 41-80 
 
 900 
 
 
 
 100 
 
 
 
 83-61 
 
 1,000 
 
 
 
 100 
 
 ~ 
 
 92-90 
 
 4,500 
 
 
 
 500 
 
 
 
 418-05 
 
 9,000 
 
 == 
 
 1,000 
 
 
 
 836-10 
 
264 WINE-MAKING IN HOT CLIMATES. 
 
 CUBIC METRES = CUBIC FEET = CUBIC YARDS. 
 
 Cubic 
 
 Cubic 
 
 Cubic 
 
 Cubic 
 
 Cubic 
 
 Cubic 
 
 metres. 
 
 feet. 
 
 yards. 
 
 metres. 
 
 feet. 
 
 yards. 
 
 1 = 
 
 35-32 
 
 = 1-31 
 
 9 - 
 
 317-85 
 
 = 11-77 
 
 2 = 
 
 70-63 
 
 zz 2-62 
 
 10 zz 
 
 353-17 
 
 = 13-08 
 
 3 = 
 
 105-95 
 
 - 3-92 15 = 
 
 529-75 
 
 = 19-62 
 
 4 = 
 
 141-27 
 
 = 5-23 20 = 
 
 706-33 
 
 = 26-16 
 
 5 =r 
 
 176-58 
 
 6-54 50 zz 
 
 1,765-83 
 
 zz 65-40 
 
 /-* 
 
 211-90 
 
 - 7-85 100 - 
 
 3,531-66 
 
 =z 130-80 
 
 < zz 
 
 247-22 
 
 - 9-16 
 
 500 zz 
 
 17,658-29 
 
 - 654-01 
 
 8 zz 
 
 282-53 
 
 = 10-46 j 
 
 1,000 = 
 
 35,316-58 
 
 = 1,308-02 
 
 1 cubic metre of water at 4 C. weighs 1,000 kilos. 
 1 cubic foot = 0-0283 cubic metre. 
 1 cubic yard = 0-7645 cubic metre. 
 
 COMPARATIVE PRESSURE PER SQUARE CENTIMETRE 
 AND PER SQUARE INCH. 
 
 Grammes per 
 square centimetre. 
 
 Lbs. per 
 square inch. 
 
 Kilos, per 
 square centimetre. 
 
 Lbs. per 
 square inch. 
 
 50 
 
 
 
 0-71 
 
 1 
 
 
 
 14-22 
 
 100 
 
 
 
 1-42 
 
 52 
 
 
 
 28-45 
 
 200 
 
 
 
 2-84 
 
 3 
 
 
 
 42-67 
 
 300 
 
 
 
 4-27 
 
 4 
 
 
 
 56-89 
 
 400 
 
 
 
 5-69 
 
 5 
 
 
 
 71-11 
 
 500 
 
 
 
 7-11 
 
 6 
 
 
 
 85-34 
 
 600 
 
 
 
 8-53 
 
 7 
 
 
 
 99-56 
 
 700 
 
 
 
 9-96 
 
 8 
 
 
 
 113-78 
 
 800 
 
 
 
 11-38 
 
 9 
 
 
 
 128-01 
 
 900 
 
 =3 
 
 12-80 
 
 10 
 
 
 
 142-23 
 
 METRIC WEIGHTS. 
 
 One decigramme 
 One gramme 
 One decagramme 
 One hectogramme 
 One kilogramme 
 
 1-543 grain. 
 15-4323 grains. 
 0-353 oz. avoirdupois. 
 3-527 ozs. 
 2-2046 Ibs. 
 
APPENDIX. 
 
 265 
 
 OUNCES AVOIRDUPOIS TO GRAMMES. 
 
 Ozs. 
 
 i 
 i 
 
 t 
 
 1 
 
 o 
 
 rW 
 
 3 
 4 
 5 
 
 6 
 
 7 
 
 Grins. 
 
 7 
 14 
 
 57 
 85 
 113 
 142 
 170 
 198 
 
 Ozs. 
 
 8 
 
 9 
 
 10 
 11 
 12 
 13 
 14 
 15 
 16 or lib. 
 
 Grms. 
 
 227 
 255 
 283 
 312 
 310 
 369 
 397 
 425 
 454 
 
 METRIC FLUID MEASURES. 
 
 One hectolitre 
 One decalitre 
 One litre 
 One decilitre 
 One centilitre 
 One millilitre 
 
 = 22-01 gallons. 
 
 = 2-201 
 
 = 0-22 or 1-76 pint. 
 
 = 3oz. 4dr. 10'4min. 
 
 = 2dr. 4-9min. 
 
 = 16-9 minims. 
 
 One pint 
 
 One quart (2 pints) 
 One gallon (4 quarts) 
 One peck (2 gallons) 
 One bushel (8 gallons) 
 One quarter (4 bushels) 
 
 0-5679 litre. 
 1-1359 ., 
 4-5435 
 9-0869 
 36-34766 
 2-9078 hectolitres. 
 
266 
 
 WINE-MAKING IN HOT CLIMATES. 
 
 Conversion of 
 Thermometer 
 Scales. 
 
 ll 
 
 u. 
 
 !! 
 
 ! 
 
 
 
 
 " 
 
 210- : 
 
 200- 
 
 
 
 ~ 
 
 
 - 
 
 _E 
 
 - 
 
 ; 
 
 _ 90 
 
 _ 
 
 . L 
 
 - 
 
 7t>_ 
 
 
 i 
 
 
 - 
 
 : -fio 
 
 -^ 
 
 ! 
 
 ~ 
 
 170 = 
 160 - 
 
 I - 
 
 60-- 
 
 :70 
 
 - 
 
 
 _; 
 
 If ft ^ 
 
 - 
 
 I 
 
 HOE 
 
 
 
 50= = 
 
 130? 
 
 - 
 
 -- 
 
 - 
 
 
 
 120: 
 
 ^jTrv 
 
 
 Ov 
 
 1 V ' 
 
 
 
 
 i 
 
 r- 
 
 - 
 
 LOOj 
 
 
 ; 
 
 1-t<> 
 
 I 
 
 
 ~3$~ 
 
 90-1 
 
 
 - 
 
 -^0 
 
 --_ 
 
 80j 
 
 = 
 
 ~zZ- 
 
 
 
 - 
 
 70 
 
 -20 
 
 - 
 
 = 
 
 
 - 
 
 60^ 
 
 
 ~ 
 
 50 1 
 
 
 ia- 
 
 
 - 
 
 40 
 
 
 - - 
 
 
 E 
 
 i 
 
 -e- 
 
 30- 
 
 
 . 
 
 20 f 
 
 - 
 
 - 
 
 ITT 
 
 - 
 
 10 j 
 
 iu: 
 
 o^? 
 
 
 - 
 
 
 
 
 Salleron's Portable Mustimetre. 
 
INDEX. 26' 
 
 GENERAL INDEX. 
 
 Page 
 
 TRANSLATORS' PREFACE ... ... ... ... .. i 
 
 CHAPTER I. Fermentation ... ... ... ... ... 3 
 
 Alcoholic fermentation ... , ... ... ... 4 
 
 Vinous fermentation ... ... ... ... ... 8 
 
 CHAPTER II. Study of the Grape ... ... .., ... 12 
 
 Maturation ... ... ... ... ... ... 12 
 
 Formation of sugars in the grape ... ... ... ... '13 
 
 Composition of ripe grapes of different cepages in the South of 
 
 France ... ... ... ... ... ... 19 
 
 Composition of grapes of the principal cepages of the South of 
 
 France ... ... ... ... ... ... 26 
 
 Aramon cepage ... ... _.;.. ... ... ... 26 
 
 Carignan cepage ... ... ... .,. ... ... 28 
 
 Petit Bouschet cepage ... ... -~'... ' ... ... 30 
 
 Picquepoul blanc cepage ... ... ... ... ... 32 
 
 Matters brought to the vat by 100 kilos of vintage ... ... 34 
 
 CHAPTER III. Vintage ... ... .... ... ... 36 
 
 Determination of sugar ... ... ... ... ... 37 
 
 Determination of acidity ... ... ... ... ... 39 
 
 Mode of operating ... .. ... ... ... 42 
 
 Influence of the time of vintage on the quality of wines ... 45 
 
 Improvement of certain vintages ... ... ... ... 53 
 
 Deficient acidity ... ... ... ... ... ... 54 
 
 CHAPTER IV. Vinification ... ... ... ... ... 56 
 
 Vinification of red wine ... ... ... ... ... 56 
 
 Crushers ... ... ... ... ... 56 
 
 Stemming ... ... ... ... ... ... 65 
 
 Stemmers ... ... ... ... ... ... 66 
 
 Advantages of stemming ... ... ... ... ... 68 
 
 Vatting... ... ... 72 
 
 Aeration of the vintage ... ... ... ... 72 
 
 Contribution to the study of vinous fermentation. Influence of 
 
 temperature (L. Roos and F. Chabert) ... ... ... 76 
 
 Opinions of various authorities as to the best temperature for 
 
 fermentation ... ... ... ... 78 
 
 Methods and apparatus employed . . . 
 
 Study of fermentations 
 
 Influence of temperature on the yield of alcohol ... ... 86 
 
 work of different yeasts 
 
 loss of alcohol 
 
 /, total acidity of wine 
 
 Action of temperature on the yeast 
 
 Influence of the temperature on the quantity of nitrogen 
 Influence of the temperature of fermentation on the yield in 
 
 alcohol ... 
 
 10649. S 
 
268 WINE-MAKING IN HOT CLIMATES. 
 
 Page 
 CHAPTER IV. Vinification continued. 
 
 Influence of the temperature of vinous fermentation on the 
 
 qualities of wine ... ... ... ... ... 103 
 
 Influence of the temperature of fermentation on the keeping 
 
 quality of wine ... ... ... ... ... ... 106 
 
 Refrigeration of musts during fermentation ... ... ... 107 
 
 Study of various must refrigerators ... ... ... 115 
 
 Method of taking the temperature of a fermenting va't . . . 126 
 
 Fermenting house ... ... ... ... ... 130 
 
 Fermenting vessels ... ... ... . . . . . 131 
 
 Fermentation ... ... ... ... ... ... 133 
 
 Pollacci's experiments ... ... . ... ... 134 
 
 Duration of vatting ... ... ... ... ... 145 
 
 Various additions to the vat ... ... ... ... 147 
 
 Acidification ... ... ... ... 147 
 
 Plastering ... ... ... ... ... 148 
 
 Phosphating... .. ... 148 
 
 Selected yeasts ... ... ... ... ... 149 
 
 De- vatting (Decuvage) ... ... ... ... 151 
 
 Exhaustion of the marc ... ... ... ... ... 152 
 
 Presses ... ... ... ... ... ... ... 152 
 
 Intermittent presses ... ... ... .. ... 152 
 
 Continuous presses ... ... ... ... ... 156 
 
 Exhaustion of marc without presses ... 163 
 
 CHAPTER V. Vinification of White Wine ... 169 
 
 Viuifi cation of white varieties ... ... ... ... 169 
 
 Fermentation ... ... ... ... ... 179 
 
 Manufacture of white wine from red grapes ... ... 1 80 
 
 New method for the Vinification of white wines ... ... 183 
 
 CHAPTER VI. Utilization of By-products ... ... ... 190 
 
 Marc ... ... ... ... ... ... ... 190 
 
 Lees and tartar ... ... ... ... ... ... 197 
 
 Determination of the percentage of bitartrate of potash in the 
 
 crust or lees ... ... ... ... 200 
 
 CHAPTER VII. Care to be given to Wine. Defects and Diseases 204 
 
 Defects and diseases of wine ... ... ... ... 206 
 
 Treatment of diseased wines ... ... ... ... 224 
 
 Heating (Pasteurizing) ... ... ... ... ... 224 
 
 Filtering and fining ... ... ... ... ... 226 
 
 Precautions to be taken to insure the efficacy of fining . . . 229 
 
 APPENDIX. 
 
 Extract from " The Vine in Australia" by Dr. A. C. Kelly, 1841. 
 
 Chapter on fermentation ... ... ... ... ... 232 
 
 The control of the temperature in wine fermentation, by A. P. 
 Hayne, Director of Viticulture, California, Bulletin No. 117, 
 
 University of California, 1 897 ... ... ... ... 238 
 
 The metric system ... ... ... ... ... ... 261 
 
 The metric and British systems ... ... ... ... 262 
 
 Conversion of thermometer scales ... ... 266 
 
INDEX. 269 
 
 ALPHABETICAL INDEX. 
 
 Page 
 A. 
 
 Acetification ... ... ... ... ... ... ... 212 
 
 Acid, sulphurous (used in vinification of white wine) ... 170 
 
 Acid, sulphurous (use in diseases) ... ... ... ... 230 
 
 Acid, tartaric (addition of) ... ... ... ... 54 
 
 Acidification... ... ... ... ... ... ... 147 
 
 Acidimetre ... ... ... ... ... ... ... 40 
 
 Acidity (defect of) ... ... ... ... ... 53 
 
 Acidity (determination of) ... ... ... ... ... 39 
 
 Acidity (influence of temperature on total acidity of wine) ... 92 
 
 Advantages of stemming .. ... ... ... ... 68 
 
 Aeration of vintage ... ... ... ... ... ... 72 
 
 Albumen (fining of wine) ... ... ... ... ... 228 
 
 Alcohol (influence of temperature of fermentation on the yield of) ... 86 
 
 Alcohol (influence of temperature on the loss of) ... ... 92 
 
 Alcoholic fermentation ... ... ... ... ... 4 
 
 Amelioration of vintage ... ... ... ... ... 53 
 
 Amertume (disease of) ... ... ... ... ... 215 
 
 Analysis of sugar in must ... ... ... ... ... 37 
 
 Analysis of acidity in must ... ... ... ... ... 39 
 
 Apparatus used for the study of fermentation at constant 
 
 temperature ... ... ... ... ... ... 81 
 
 Apparatus used for collecting the alcohol carried away mechanically 
 
 during fermentation ... ... ... ... ... 91 
 
 Aramon (composition of grapes) ... ... ... ... 26 
 
 Arrangement of Coste-Floret, for fermentation ... ... ... 137 
 
 Arrangement of Ermens, for refrigeration ... ... ... 108 
 
 Arrangement in the laboratory showing the displacement of wine 
 
 by water ... ... ... ... ... ... 164 
 
 Auto-regulator for fermentation ... ... ... ... 142 
 
 Auto-regulator fixed on vat ... ... ... ... ... 143 
 
 Automatic registering apparatus for gas liberated during fermenta- 
 tion, of Houdaille ... ... ... ... ... 83 
 
 B. 
 
 Blood, its use in fining ... ... ... ... ... 227 
 
 Bouquet of wines, its origin ... ... ... ... ... 23 
 
 Break jet, for spraying must ... ... ... ... ... 139 
 
 By-products, utilization of ... ... ... ... ... 190 
 
 C. 
 
 Cambon's apparatus ... ... ... ... ... . 141 
 
 Care to be given to wine 
 
 Carignan (composition of grape) 
 
 Casse (disease of) 
 
 Climagene chimney ... 
 
 Climagene chimney. Dessoliers (arrangement of cellular bricks) 
 
 Clarifying of wines 
 
 Colour of wine (yellow colour) . . . 
 
 204 
 28 
 218 
 112 
 112 
 226 
 207 
 
 Colouring matter of grapes ... ... ... ... ... 22 
 
270 WINE-MAKING IN HOT CLIMATES. 
 
 Page 
 
 Composition of must ... ... ... ... ... ... 20 
 
 Composition of ripe grapes of principal cepayes .. ... ... 34 
 
 Composition of principal cepages ... ... ... ... 26 
 
 Composition of experimental wines (stemming) ... ... ... 70 
 
 Composition of medium-sized canes (table) ... ... ... 16 
 
 Composition of medium-sized canes (diagram) ... ... ... 17 
 
 Composition of stalks ... ... ... ... ... ... 19 
 
 Composition of seeds ... ... ... ... ... ... 24 
 
 Continuous press ... ... ... ... ... ... 156 
 
 Contribution to the study of vinous fermentations ... ... 76 
 
 Contribution to the study of vinous fermentations (conclusions) . . 98 
 
 Correction of the saccharine strength of must ... ... ... 54 
 
 Crushers ... ... ... ... ... ... ... 56 
 
 Crusher (side view of Blaquieres) ... ... ... ... 59 
 
 Crusher (top view of Blaquieres) ... ... ... ... 60 
 
 Crusher (front view of Blaquieres) ... ... ... ... 59 
 
 Crusher (arrangement of cylinder on vat) ... ... ... 57 
 
 Crusher, drainer, and stemmer (side view of Blaquieres) ... ... 67 
 
 Crushing ... ... ... ... ... ... ... 56 
 
 D. 
 
 Debourbage ... ... ... ... ... ... ... 169 
 
 Defects and diseases of vines ... ... ... ... ... 206 
 
 Determination of the strength of crude tartar in lees ... ... 200 
 
 De-vatting ... ... ... ... .. ... 151 
 
 Diplococcus aceti ... ... ... ... ... ... 212 
 
 Disease of acetification (vinegar) ... ... ... ... 212 
 
 Disease of amertume (bitter) ... ... ... ... ... 215 
 
 Disease of casse (breakage) ... ... ... ... ... 218 
 
 Disease of fleur (flower) ... .. ... ... ... 211 
 
 Disease of graisse (fat) ... ... ... ... '... 216 
 
 Disease of pousse (pushing) ... ... ... ... ... 215 
 
 Disease of tourne (turning) ... ... ... ... ... 213 
 
 Diseased wines, treatment of ... ... ... ... ... 224 
 
 Diseases, treatment used in ... ... ... .. ... 224 
 
 Diseases of wines .'.. ... ... ... ... ... 206 
 
 Drainage of marcs ... ... ... ... ... ... 152 
 
 Drainage of marcs without press ... ... ... ... 163 
 
 E. 
 
 Earthy taste... ... ... ... ... ... ... 208 
 
 F. 
 
 Fermentation ... ... ... ... ... ... 133 
 
 Fermentation (alcoholic) ... ... ... ... ... 4 
 
 Fermentation (duration of) ... ... ... ... ... 145 
 
 Fermentation, experiments of Pollacci ... ... ... ... 134 
 
 Fermentation (products of alcoholic) ... ... ... ... 6 
 
 Fermentation (with single submerged head) ... ... ... 136 
 
 Fermentation (with multiple submerged heads) ... ... ... 136 
 
 Fermentation (arrangement of Coste-Floret) ... ... ... 137 
 
 Fermentation, mannitic ... ... ... ... ... 216 
 
 Fermentation, vinous ... ... ... ... ... ... 8 
 
 Fermentations (contributions to the study of vinous) ... ... 76 
 
INDEX. 271 
 
 Page 
 
 Fermentation (opinions of different authors as to the best tempera- 
 ture of vinous) ... ... ... ... ... 7& 
 
 Fermenting vats ... ... ... ... ... 131 
 
 Filling of casks ... ... ... ... ... ... 204 
 
 Filtering ... ... ... '.'.'. '.. 226 
 
 Fleur (disease of) ... ... ... ... ... ... 211 
 
 Formation of sugar in grapes ... ... ... ... ... 13 
 
 G. 
 
 Gelatine, its use in the fhui; f wine ... ... ... ... 228 
 
 Glucometre, Guyot ... ... ... ... ... ... 37 
 
 Graisse (disease of) ... ... ... , ... ... ... 216 
 
 I. 
 
 Influence of temperature of fermentation on the total acidity of wine 92 
 
 Influence of temperature of fermentation on the loss of alcohol ... 91 
 
 Influence of temperature of fermentation on the yield of alcohol ... 98 
 Influence of temperature of fermentation on the quantity of nitrogen 
 
 in wine ... ... ... ... ... ... ... 93 
 
 Influence of temperature of fermentation on the quality of wine . . . 103 
 
 Influence of temperature of fermentation on the composition of wine 86 
 
 Influence of temperature on the action of yeasts ... ... 92 
 
 Intermittent presses ... ... ... ... ... ... 52 
 
 L. 
 
 Leaden-coloured wine ... ... ... ... ... 207 
 
 Lees, of wine ... .-.; ... ... ... ... 197 
 
 M. 
 
 Marc, utilization of ... ... ... ... ... ... 190 
 
 Manufacture of white wines ... .-- ... ... ... 169 
 
 Manufacture of white wine, new process for ... ... ... 183 
 
 Manufacture of white wine from red grapes ... ... ... 180 
 
 Manufacture of red wine ... ... ... ... ... 56 
 
 Matters brought to the vat by 100 kilos of vintage . ... ... 34 
 
 Matters, colouring of grapes ... ' ... ... ... ... 22 
 
 Milk, its use in fining ... ... ... ... ... 227 
 
 Must, its composition .. . ... .., ... ... ... 20 
 
 Mustard powder, use of ... ... ... ... ... 210 
 
 Mustimetre, Salleron ... ... ... ... ... ... 38 
 
 Mutage ... ... ... ... ... 171 
 
 Muteuses ... ... ... .., ... ... ... 171 
 
 Muteuse, Coste-Floret ... ... ... ... ... 171 
 
 Muteuse, P. Paul ... 172 
 
 Muteuse, du Bosquet ... ... ... ... 173 
 
 Muteuse, Thomas and Roos ... ... ... ... ... 175 
 
 Muteuse, Thomas and Roos, arrangement for the bung hole ... 176 
 
 Mycoderma aceti 
 
 Mycoderma vini ... ... ... ... ... 211 
 
 0. 
 
 Opinion of different authors on the best temperatures of fermenta- 
 tion ... ... ... ... 78 
 
 Origin of the perfume of wine ... 23 
 
 Olive oil, its use in diseases of wine ,.. ... .. ... 210 
 
272 WINE-MAKING IN HOT CLIMATES. 
 
 P. Page 
 
 Petit-Bouschet, composition of grape ... ... ... ... 30 
 
 Phosphating . . . ... ... ... ... ... 148 
 
 Picquepoul, composition of grape ... ... ... ... 32 
 
 Piquettes ... ... ... ... ... ... ... 190 
 
 Piquettes, plan of arrangement for ... ... ... ... 194 
 
 Plastering ... ... ... ... ... 148 
 
 Pousse ... ... ... ... ... ... 215 
 
 Precaution to be observed to insure success in fining ... ... 229 
 
 Presses ... ... ... ... ... ... ... 152 
 
 Presses, continuous ... ... ... ... ... ... 156 
 
 Presses, type of continuous ... ... ... ... ... 157 
 
 Presses, intermittent ... ... ... ... ... 152 
 
 Presses, type of ordinary ... ... ... ... ... 153 
 
 Press, with spring load ... ... .. ... ... 154 
 
 Pumping the must over the head ... ... ... ... 138 
 
 Q. 
 
 Quality of wines, action of acidity on ... ... ... ... 47 
 
 Qualitj 7 of wines, influence of the time of vintage on ... ... 45 
 
 Quality of wines, influence of the temperature of fermentation on ... 103 
 
 R. 
 
 Racking ... ... ... ... ... ... ... 152 
 
 Refrigeration, arrangement of Ermens ... ... ... ... 108 
 
 Refrigeration of must during fermentation ... ... ... 107 
 
 Refrigerators for must during fermentation ... ... ... 108 
 
 Refrigerators for musts, trials of ... ... ... ... 120 
 
 Refrigerator, Andrieu ... ... ... ... ... 124 
 
 Refrigerator, Muntz and Rousseau ... ... ... ... 116 
 
 Refrigerator, Paul ... ... ... . ... ... ... 117 
 
 Refrigerator, Rouviere Hue ... ... ... ... ... 122 
 
 S. 
 
 Saccharomyces apiculatus ... ... ... ... ... 9 
 
 Saccharomyces cere visse ... ... ... ... ... 6 
 
 Saccharomyces ellipsoideus .. ... ... ... ... 9 
 
 Seeds, grape, composition of ... ... ... ... ... 24 
 
 Smell, putrid, in wine ... ... ... ... ... 210 
 
 Stalks, grape, composition of ... ... ... ... ... 21 
 
 Stemmers ... ... ... ... ... ... ... 66 
 
 Stemmer, arrangement on vat ... ... ... .. ... 66 
 
 Stemming ... ... ... ... ... ... ... 65 
 
 Stemming, when necessary ... ... ... ... ... 68 
 
 Stemming, composition of wines experimented on ... ... 70 
 
 Sulphuring ... ... ... ... ... ... ... 230 
 
 Sulphuring with pump ... ... ... ... ... 231 
 
 Sugar, determination of ... ,.. .... ... ... 37 
 
 Sulphite, alkaline, uses of ... ... ... ... ... 170 
 
 T. 
 
 Table showing the nitrogen content of wines made at different 
 
 temperatures ... ... ... ... ... ... 94 
 
 Tables, comparing fermentation at different temperatures ... 95 
 
 Tap Trabut, for aeration of musts ... ... ... ... 140 
 
INDEX. 273 
 
 Page 
 
 Tartar, crude, determination of ... ... ... 200 
 
 Temperature of fermenting vat, measurement of ... 126 
 
 Temperature of fermentations, opinions of various authors on the 
 
 best ... ... ... ... ... ._ _ 7g 
 
 Thermometer, self -registering ... ... ... 127 
 
 Treatment of diseased wines ... ... 224 
 
 Trials of must refrigerators ... ... ... ... 115 
 
 Tube, acidimetric, Salleron ... ... ... 49 
 
 Turbine, aero-crushing ... ... ... ][[ QI 
 
 Type of continuous press ... .. ... 157 
 
 Type of intermittent press ... ... ... ... 153 
 
 U. 
 
 Utilization of by-products ... ... 190 
 
 Utilization of by-products, marc .. .. 190 
 
 Utilization of by-products, lees and tartars ... ... 197 
 
 V. 
 
 Vats, arrangement of fermenting ... ... ... 136 
 
 Vessels used in fermentation .., ... ... ... 131 
 
 Vintage ... ... ... ... ... ... ... 35 
 
 Vintage, aeration of ... ... ... ... ... ... 72 
 
 Vintage, improvement of certain ... ... ... 53 
 
 W. 
 
 Wines, care to be given to ... ... ... ... ... 204 
 
 Wines, treatment of diseases of ... ... ... 224 
 
 Wines, leaden colour of ... ... ... ... ... 207 
 
 Y. 
 
 Yeast, action of temperature on ... ... ... ... 92 
 
 Yeast, beer ... ... ... ... ... ... ... 6 
 
 Yeast, wine ... ... ... ... ... ... ... 8 
 
 Yeast, composition of ... ... ... ... ... 7 
 
 Yeast, influence of temperature on the work of different ... ... 90 
 
 Yeasts, selected ... ... ... ... ... ... 149 
 
 Yellow colour of wine ... ... ... ... ... 207 
 
 By Authority : ROBT. S. BRAIN, Government Printer, Melbourne. 
 
PUBLICATIONS RELATING TO VITICULTURE, 
 
 BY W. PERCY WILKINSON. 
 
 THE ALCOHOLIC STRENGTH OF VICTORIAN WINES EXHIBITED AT THE 
 MELBOURNE INTERNATIONAL EXHIBITION 1888. Official record, Mel- 
 bourne Centennial International Exhibition, pp. 305-317, 8vo. 
 Melbourne, 1888-9. 
 
 THE ALCOHOLIC STRENGTH OF VICTORIAN WINES. Journal of the Board 
 of Viticulture, No. 5, pp. 81-96. Melbourne, 1892. 
 
 THE SUGAR STRENGTH AND ACIDITY OF VICTORIAN MUSTS, WITH 
 REFERENCE TO THE ALCOHOLIC STRENGTH OF VICTORIAN WlNES. 
 
 Part 1. Report of the Australasian Association for the Advance- 
 
 ment of Science, pp. 306-315. Adelaide, 1893. 
 Part 2. Proceedings of the. Royal Society of Victoria, pp. 89-118. 
 Melbourne, 1894. 
 
 ACIDITY IN MUSTS. Editorial Note. Translated from the Revue de 
 Viticulture, pp. 239, 240. 1895. The Australian Vigneron, pp. 
 330, 331. Sydney, 1895. 
 
 REFRIGERATION IN WINK-MAKING. A. Barbier. Translated from the 
 Revue de Viticulture, pp. 374-376. 1895. The Australian Vigneron, 
 p. 379. Sydney, 1896. 
 
 WINE-MAKING IN HOT CLIMATES. U. Gayon. Translated from the 
 Revue de Viticulture. January, 1896. The Australian Vigneron, 
 pp. 386, 387. Sydney, 1896. 
 
 A RESUME OF MM. MUNTZ AND ROUSSEAUX'S STUDIES ON* THE IMPORT- 
 ANCE OF REFRIGERATION OF MUSTS IN WINE-MAKING. Translated 
 from the Revue de Viticulture. 1896. Extract from The Australian 
 Vigneron, p. 20. Sydney, 1896. 
 
 SALICYLIC ACID IN WINE (LAWS IN EUROPE RELATING TO). The Aus- 
 tralian Vigneron, pp. 63, 64. Sydney, 1896. 
 
 THE ESTIMATION OF FUSEL OIL IN SPIRITS : OFFICIAL METHOD OF THE 
 GERMAN GOVERNMENT. Extract from The Australian Vigneron, 
 p. 8. Sydney, 1898. 
 
 AMERICAN VINES : THEIR ADAPTATION, CULTURE, GRAFTING, AND PRO- 
 PAGATION. By P. Viala and L. Ravaz. Translated abridgement of 
 the second French edition. By W. Percy Wilkinson and Joseph 
 Gassies, pp. viii., 88. Melbourne, 1897. 
 
 AN EXAMINATION OF THE WINES RETAILED IN VICTORIA. Australasian 
 Association for Advancement of Science. Melbourne, 1900'. 
 
 BY RAYMOND DUBOIS, 
 
 THE COMPOSITION OF NATURAL WINES. A paper read before the Aus- 
 tralasian Association for Advancement of Science. Melbourne, 1900. 
 

 
 
 
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