fcppp .{5-;;iif it!ii: : MICHELS Ui A. UNIVERSITY FARM a G Creamery Butter BY JOHN MICHELS, B. S. A., M. S. ASSOCIATE PROFESSOR OF DAIRYING AND ANIMAL HUS . BANDRY, NORTH CAROLINA STATE AGRICULTURAL COLLEGE. AUTHOR OF DAIRY FARMING ILLUSTRATED RALEIGH, NORTH CAROLINA PUBLISHED BY THE AUTHOR 1907 ALL RIGHTS RESERVED COPYRIGHTED BY JOHN MICHELS 1904 PREFACE. The author's experience in teaching creamery students has demonstrated to him the need of a suitable reference book to be used in conjunction with the lectures on cream- ery butter making. An attempt to supply this need has resulted in the preparation of this work, which embodies the results of a long experience both as a practical butter maker and as a teacher of creamery management. Special emphasis has been laid upon starters, pasteur- ized butter making, methods of creamery construction, and creamery mechanics, subjects which have usually been treated only in a very elementary way in similar publica- tions that have appeared heretofore. The historical side of the various phases of butter mak- ing has in the main been omitted, not' because it was deemed uninteresting, but for fear of making this volume too bulky. With the appended glossary explaining all unavoidable technical terms, this treatise is offered to the public as a suitable hand-book for the student as well as for the butter maker who cannot attend a dairy school. JOHN MICHELS. Michigan Agricultural College, March, 1904. 185883 INTRODUCTION. The "rule of thumb" butter making days are gone by.- Xo one at the present time can hold any important posi- tion in the profession of butter making unless thoroughly grounded in the principles that underlie it. It is true many obscure problems yet remain to be solved, but by the aid of the bacteriologist and chemist butter making has now been fairly placed upon a scientific basis. I bacteriology has shed no less light upon the various processes involved in the manufacture of butter than it has upon the nature and causes of the diseases with which mankind is afflicted. The souring of milk, the ripening of cream, the causes of the various taints common to milk and cream are now quite thoroughly understood. Along with this understanding have come many radical changes in the handling of milk and cream and their manufacture into butter as well as in the handling of butter itself. The best butter makers at the present time are the men who are the most diligent students of bacteria and their relation to butter making processes. Above their doors is written in emblazoned letters "Cleanliness is next. to Godliness." For cleanliness is the foundation of success in butter making. THE (UNIVERSITY) TABLE OF CONTENTS. Page Chapter I. Milk 1 1 Chapter II. The Babcock Test 23 Chapter III. The Lactometer and Its Use 34 Chapter IV. Bacteria and Milk Fermentations. 42 Chapter V. Composite Sampling 51 Chapter VI. Creaming 57 Chapter VII. Cream Ripening 68 Part I. Theory and Methods of Ripening 68 Part II. Control of Ripening Process.... 73 Part III. Cream Acid Tests. ; . ... 81 Chapter VIII. Starters 88 Chapter IX. Churning 100 Chapter X. Packing and Marketing Butter 114 Chapter XL Calculating Dividends 119 Chapter XII. Theoretical Overrun 128 Chapter XIII. Distribution of Skim-milk and Buttermilk. 130 Chapter XIV. Butter Judging 134 Chapter XV. Location and Construction of Creameries. . 141 a. Model Creamery Illustrated 143 b. Cost of Building 158 c. Cost of Equipment 159 Chapter XVI. Creamery Mechanics 165 a. The Steam Boiler 165 b. The Steam Engine 179 c. Calculating Size and Speed of Pulleys. . 188 d. Friction : Its Advantage and Disad- vantage 191 e. Tools, Packing and Steam Fittings. .... 194 f. Valves 196 g. Lining up Shafting 198 Chapter XVII. Pasteurization as Applied to Butter Making 2O Chapter XVIII. Co-o'peration 2*5, Chapter XIX. Detection of Tainted or Impure Milk 219 10 CONTENTS Page Chapter XX. Care of Milk and Skim-milk 22$ Chapter XXI. Handling and Testing Cream 227 Chapter XXII. Mechanical Refrigeration 232 Chapter XXIII. Creamery Book-keeping 241 Appendix 250 Glossary 261 Index 265 . CREAMERY BUTTER MAKING. CHAPTER I. MILK. Milk, in a broad sense, may be defined as tbe normal secretion of the mammary glands of animals that suckle their young. It is the only food found in Nature con- taining all the elements necessary to sustain life. Moreover it contains these elements in the proper pro- portions and in easily di- gestible and assimilable form. Designed by Nature to nourish the young,, milk was originally used entirely for this purpose and secre- ted only a short time after parturition. For many cen- turies, however, it has been used as an important part of the human dietary and cows at the present time yield milk almost incessantly. Because of its nutritive qualities its use as a dietetic is rapidly increasing. Physical Properties. Milk is a whitish opaque fluid possessing a sweetish taste and a faint ordor suggestive of cow's breath. It has an amphioteric reaction, that is, 11 Weigh can showing gate opener. 12 CREAMERY BUTTER MAKING it is both acid and alkaline. This double reaction is due largely to acid and alkaline salts and possibly to small quantities of organic acids. Milk has an average normal specific gravity of 1.032, with extremes rarely exceeding 1.029 and 1.033. After standing a few moments it loses its homogenous character. Evidence of this we have in the "rising of the cream." This is due to the fact that milk is not a perfect solution but an emulsion. All of the fat, the larger portion of the casein, and part of the ash are in suspension. In consistency milk is slightly more viscous than water, the viscosity increasing with the decrease in temperature. It is also exceedingly sensitive to odors, possessing great absorption properties. This teaches the :_rccssity of plac- ing milk in clean pure surroundings. Chemical Composition. The composition of milk is very complex and variable, as will be seen from the fol- lowing figures : Average Composition of Normal Milk. A com- pilation of figures from various American Ex- periment Stations. Water 87.1* Butter fat 3.9^ Casein : 2.9^ Albumen 5# Sugar 4.9^ Ash 7^ Fibrin Trace. Galactase Trace. 100. The great variations in the composition of milk are shown by the figures from Koenig, given below : . CREAMERY BUTTER MAKING 13 Maximum. Minimum. Water 90-69 80.32 Fat 6.47 1.67 Casein 4.23 1.79 Albumen 1.44 .25 Sugar 6.03 2. ii Ash 1. 21 .35 These figures represent quite accurately the maximum and minimum composition of milk except that the maxi- mum for fat is too low. The author has known cows to yield milk testing 7.6% fat, and records show tests even higher than this. BUTTER FAT. " This is the most valuable as well as the most variable constituent of milk. It constitutes about 83% of butter and is an indispensable constituent of the many kinds of whole milk cheese now found upon the market. It also measures the commercial value of milk and cream, and is used as an index of the value of milk for butter and cheese production. Physical Properties. Butter fat is suspended in milk in the form of extremely small globules numbering about 100,000,000 per drop of milk. These globules vary con- siderably in size in any given sample, some being five times as large as others. The size of the globules is affected mostly by the period of lactation. As a rule the size decreases and the number increases with the advance of the period. In strippers' milk the globules are some- times so small as to render an efficient separation of the cream and the churning of same impossible. The size of the fat globules also varies with different breeds In tlu? Jersey breed the diameter of the globule 14 CREAMERY BUTTER MAKING - " is one eight-thousandth of an inch, in the Holstein one twelve-thousandth, while the average for all breeds is about one ten-thousandth. Night's milk usually has smaller globules than morn- ing's. The size of the globules also decreases with the age of the cow. The density or specific gravity of butter fat at 100 F. is .91 and is quite constant. Its melting point varies between wide limits, the average being 92 F. Composition of Butter Fat. According to Richmond, butter fat has the following composition : Butyrin 3.85 ) Caproin 3.60 I Soluble or volatile. Caprylin 55 j Caprin i .90 Laurin 7.40 Myristin 20.20 ! Insoluble or Palmitin 25 . 70 f non-volatile. Stearin i . So j Olein, etc 35-OO J This shows butter fat to be composed of no less, than nine distinct fats, which are formed by the union of glycerine w r ith the corresponding fatty acids. Thus, buty- rin is a compound of glycerine and butyric acid ; palmitin, a compound of glycerine and palmitic acid, etc. The most important of these acids are palmitic, oleic, and butyric. Palmitic acid is insoluble, melts at 144 F., and forms (with stearic acid) the basis of hard fats. Oleic acid is insoluble, melts at 57 F., and forms the basis of soft - fats. CREAMERY BUTTER MAKING 15 Butyric acid is soluble and is a liquid which solidifies at 2 F. and melts again at 28 F. Insoluble Fats. A study of these fats is essential in elucidating the variability of the churning temperature of cream. As a rule this is largely determined by the relative amounts of hard and soft fats present in butter fat. Other conditions the same, the harder the fat the higher the churning temperature. Scarcely any two milks contain exactly the same relative amounts of hard and soft fats, and it is for this reason that the churning tem- perature is such a variable one. The relative amounts of hard and soft fats are influ- enced by : 1. Breeds. 2. Feeds. 3. Period of lactation. 4. Individuality of cows. T-he butter fat of Jerseys is harder than that of Hoi- steins and, therefore, requires a relatively high churning temperature, the difference being about six degrees. Feeds have an important influence upon the character of the butter fat. Cotton seed meal and bran, for example, materially increase the percentage of hard fats. Gluten feeds and linseed meal, on the other hand, produce a soft butter fat. With the advance of the period of lactation the per- centage of hard fat increases. This chemical change, to- gether with the physical change which butter fat under- goes, makes churning difficult Jn the late period of lac- tation. The individuality of the cow also to a great extent influences the character of the butter fat. It is inherent 16 CREAMERY BUTTER MAKING in some cows to produce a soft butter fat, in others to produce a hard butter fat, even in cows of the same breed. Soluble Fats. The soluble or volatile fats, of which butyrin is the most important, give milk and sweet cream butter their characteristic flavors. Butyrin is found only in butter fat and distinguishes this from all vegetable and other animal fats. The percentage of soluble fats decreases with the period of lactation, also with the feeding of dry feeds and those rich in protein. Succulent feeds and those rich in carbo- hydrates, according to experiments made in Holland and elsewhere, increase the percentage of soluble fats. This may partly account for the superiority of the flavor of June butter. It may be proper, also, to discuss under volatile or soluble fats those abnormal flavors that are imparted to milk, cream, and butter by weeds like garlic and wild onions, and by various feeds such as beet tops, rape, par- tially spoiled silage, etc. These flavors are undoubtedly due to abnormal volatile fats. Cows should never be fed strong flavored feeds shortly before milking. When this is done the odors are sure to be transmitted to the milk and the products therefrom. When, however, feeds of this kind are fed shortly after milking no bad effects will be noticed at the next milking. Albumenoids. These are nitrogenous compounds which give milk its high dietetic value. Casein, albumen, globulin, and nuclein form the albumenoids of milk, the casein and albumen being by far the most important. Casein. This is a white colloidal substance, possessing neither taste nor smell. It is the most important tissue- forming constituent of milk and forms the basis of an almost endless variety of cheese. CREAMERY BUTTER MAKING 17 The larger portion of the casein is suspended in milk in an extremely finely divided amorphus condition. It is intimately associated with the insoluble calcium phosphate of milk and possibly held in chemical combination with this. Its study presents many difficulties, which leaves its exact composition still undetermined. Casein is easily precipitated by means of rennet extract and dilute acids, but the resulting precipitates are not identically the same. It is not coagulated by heat. Albumen. In composition albumen very closely re- sembles casein, differing from this only in not containing sulphur. It is soluble and unaffected by rennet, which causes most of it to pass into the whey in the manufacture of cheese. It is coagulated at a temperature of 170 F. It is in their behavior toward heat and rennet that casein and albumen radically differ. Milk Sugar. This sugar, commonly called lactose, has the same chemical composition as cane sugar, differing from it chiefly in possessing only a faint sweetish taste. It readily changes into lactic acid when acted upon by the lactic acid'bacteria. This causes the ordinary phenom- enon of milk souring. The maximum amount of acid in milk rarely exceeds .9%, the germs usually being checked or killed before this amount is formed. There is there- fore always a large portion of the sugar left in sour milk. All of the milk sugar is in solution. Ash. Most of the ash of milk exists in solution. It is composed of lime, magnesia, potash, soda, phosphoric acid, chlorine, and iron, the soluble lime being the most important constituent. It is upon this that the action of rennet extract is dependent. For when milk is heated to high temperatures the soluble lime is rendered insoluble and rennet will no longer curdle milk. It seems also that 18 CREAMERY BUTTER MAKING the viscosity of milk and cream is largely due to soluble lime salts. Cream heated to high temperatures loses its viscosity to such an extent that it can not be made to "whip." Treatment with soluble lime restores its orig- inal viscosity. The ash is the least variable constituent of milk. Colostrum Milk. This is the first milk drawn after parturition. It is characterized by its peculiar odor, yel- low color, broken down cells, and high content of albu- men which gives it its viscous, slimy appearance and causes it to coagulate on application of heat. According to Eugling the average composition of colos- trum milk is as follows : Water 71.69^ Fat .3.37 Casein 4.83 Albumen 15.85 Sugar ,. 2 . 48 Ash- 1.78 The secretion of colostrum milk is of very short dura- tion. Usually within four or five days after calving it assumes all the. properties of normal milk. In some cases, however, it does not become normal till the sixth or even the tenth day, depending largely upon the condition of the animal. A good criterion in the detection of colostrum milk is its peculiar color, odor, and slimy appearance. The dis- appearance of these characteristics determines its fitness for butter production. Milk Secretion. Just how all of the different con- stituents of milk are secreted is not yet definitely understood. But it is known that the secretion takes CREAMERY BUTTER MAKING 19 place in the udder of the cow, and principally during the process of milking. Further, the entire process of milk elaboration seems to be under the control of the nervous system of the cow. This accounts for the changes in flow and richness of milk whenever cows are subjected to abnormal treatment. It is well known that a change of milkers, the use of rough language, or the abuse of cows with dogs and milk stools, seriously affects the production of milk and butter fat. It is therefore of the greatest practical importance to milk producers to treat cows as .gently as possible, especially during the process of milking. How Secreted. The source from which the milk con- stituents are elaborated is the blood. It must not be sup- posed, however, that all the different constituents already exist in the blood in the form in which we find them in milk, for the blood is practically free from fat, casein, and milk sugar. These substances must then be formed in the cells of the udder from material supplied them by the blood. Thus there are in the udder cells that have the power of secreting fat in a manner similar to that by which the gastric juice is secreted in the stomach. Simi- larly, the formation of lactose is the result of the action of another set of cells whose function is to produce lac- tose. It is believed that the casein is formed from the albumen through the activity of certain other cells. The water, albumen, and soluble ash probably pass directly from the blood into the milk ducts by the process known as osmosis. Variations in the Quality of Milk. Milk from dif- ferent sources may vary considerably in composition, particularly in the percentage of butter fat. Even the 20 CREAMERY BUTTER MAKING milk from the same cow may vary a great deal in compo- sition. The causes of these variations may be assigned to two sets of conditions : I. Those natural to the cow. IL Those of an artificial nature. ^- I. QUALITY OF MILK AS AFFECTED BY NATURAL CONDI- TIONS. 1. The composition of the milk of all cows undergoes a change with the advance of the period of lactation. During the first five months the composition remains prac- tically the same. After this, however, the milk becomes gradually richer until the cow "dries up." The following figures from Van Slyke illustrate this change : Month of Per cent of fat lactation. in milk. 1 4-54 2 4-33 3 4-28 4 4-39 5 4-38 6 4-53 7 4o6 8 4.66 9 4-79 10 - 5.00 It will be noticed from these figures that the milk actually decreases somewhat in richness during the first three months of the period. But just before the cow dries up, it may test as high as 8%. 2. The quality of milk also differs with different breeds. Yet breed differences are less marked than those of the individual cows of any particular breed. Some breeds produce rich milk, others relatively poor CREAMERY BUTTER MAKING 21 milk. The following data obtained at the New Jersey Experiment Station illustrates these differences : Breed. Total Solids. Fat. Milk Sugar. Proteids. Ash. Ayshire Per cent. 12.70 Per cent. 3.68 Per cent. 4.84 Per cent. 3.48 Per cent. .69 Guernsey 14 48 5 02 4.80 3.92 .75 Holstein 12.12 3.51 4.69 3.28 .64 Jersey . . 14.34 4 78 4.85 3.96 .75 3. Extremes in the composition of milk' are usually to be ascribed to the individuality or "make up" of the cow. It is inherent in some cows to produce rich milk, in others to produce poor milk. In other words, Nature has made every cow to produce milk of a given richness, which can not be perceptibly changed except by careful selection and breeding for a number of generations. II. QUALITY OF MILK AS AFFECTED BY ARTIFICIAL CON- DITIONS. 1. When cows are only partially milked they yield poorer milk than when milked clean. This is largely explained by the fact that the first drawn milk is always poorer in fat than that drawn last. Fore milk may test as low as .8%, while the strippings sometimes test as high as 14%. 2. Fast milking increases both the quality and the quantity of the milk. It is for this reason that fast milkers are so much preferred to slow ones. 22 CREAMERY BUTTER MAKING 3. The richness of milk is also influenced by the length of time that elapses between the milkings. In general, the shorter the time between the milkings the richer the milk. This, no doubt, in a large measure accounts for the differences we often find in the richness of morning's and night's milk. Sometimes the morning's milk is the richer, at other times the evening's, depending largely upon the time of day the cows are milked. Milk can not, however, be permanently enriched by milking three times in stead of twice a day. 4. Unusual excitement o.f any kind reduces the quality of milk. The person who abuses cows by dogs, milk stools, or boisterousness, pays dearly for it in a reduction of both the quality and the quantity of milk produced. 5. Starvation also seriously affects both the quality and the quantity of milk. It has been repeatedly shown, in this country and in Europe, that under-feeding to. any great extent results in the production of milk poor in fat. 6. Sudden changes of feed may slightly affect the richness of milk, but only temporarily. So long as cows are fed a full ration, it is not possible to change the richness of milk permanently, no matter what the character of feed composing the ration. 7. Irregularities of feeding and milking, exposure to heat, cold, ram, and flies, tend to reduce both the quantity and the quality of milk produced. CHAPTER II. THE BABCOCK TEST. This is a cheap and simple device for determining the percentage of fat in milk, cream, skim-milk, buttermilk, whey, and cheese. It was invented in 1890 by Dr. S. M. Babcock, of the Wisconsin Agricultural Experiment Sta- tion, and ranks among the leading agricultural inventions of modern times. The chief uses of the Babcock test may. be mentioned as follows : 1. It has made possible the payment for milk accord- ing to its quality. 2. It has enabled butter and cheese makers to detect undue losses in the process of manufacture. 3. It has made possible the grading up of dairy herds by locating the poor cows. 4. It has, in a large measure, done away with the prac- tice of watering and skimming milk. Principle of the Babcock Test. The separation of the butter fat from milk with the Babcock test is made possible : 1. By the difference between the specific gravity of butter fat and milk serum. 2. By the centrifugal force generated in the tester. 3. By burning the solids not fat with a strong acid. Sample for a Test. Whatever the sample to be tested, always eighteen grams are used for a test. In testing cream and cheese, the sample is weighed. For testing- milk, skim-milk, buttermilk, and whey, weighing requires 23 24 CREAMERY BUTTER MAKING too much time. Indeed, with these substances weighing is not necessary as sufficiently accurate samples are ob- Fig. l. Babcock tester. tained by measuring which is the method universally em- ployed. In making a Babcock test it is of the greatest importance to secure a uniform sample of the substance to be tested. CREAMERY BUTTER MAKING 25 Apparatus. This consists essentially of the following parts : A, Babcock tester ; B, milk bottle ; C, cream bottle ; D, skim-milk bottle ; E, pipette or milk measure ; F, acid measures ; G, cream scales ; H, mixing cans ; I, dividers. A. Babcock Tester. This machine, shown in Fig. I, consists of a revolving wheel placed in a horizontal posi- tion and provided with swinging pockets for the bottles. This wheel is rotated by means of a steam turbine wheel in the bottom or at the top of the tester. When the tester stops the pockets hang down allowing the bottles to stand up. As the wheel begins rotating the pockets move out causing the bottles to assume a horizontal position. Both wheels are enclosed in a cast iron frame provided with a cover. B. Milk Bottle. This has a neck graduated to ten large divisions, each of which reads one per cent. Each large division is subdivided into five smaller ones, making each subdivision read .2%. The contents of the neck from the zero mark to the 10% mark is equivalent to two cubic centimeters. Since the Babcock test does not give the percentage of fat by volume but by weight, the 10% scale on the neck of the bottle will, therefore, hold 1.8 grams of fat. In other words, if the scale were filled with water it would hold two grams ; but fat being only .9 as heavy, 2 cubic centimeters of it would weigh nine- tenths of two grams or 1.8 grams. This is exactly 10% of 1 8 grams, the weight of the sample used for testing. A milk bottle is shown in Fig. 2. C. Cream Bottles. These are graduated from 30% to 55%. A 30% bottle is shown in Fig. 3. Since cream usually tests more than 30%, the sample must be divided when the 30% bottles are used. 26 CREAMERY BUTTER MAKING Fig. 3. Cream bottle. Fig. 4. Skim-milk bottle. D. Skim=milk Bottle. This bottle, shown in Fig. 4, is provided with a double neck, a large one to admit the milk, and a smaller graduated neck for fat reading. The entire scale reads one-half per cent. Being divided into ten subdivisions each subdivision reads .05%. The same bottle is also used for testing buttermilk. CREAMERY BUTTER MAKING 27 \ Fig. 5. Pi- pette. Fig. 6. Acid meas- ure. Fig. 7 - Acid meas- ure. E. Pipette. This holds 17.6 c.c., as shown in Fig. 5. Since about .1 c.c. of milk will adhere to the inside of the pipette it is ex- pected to deliver only 17.5 c.c., which is equiva- lent to 1 8 grams of normal milk. F. Acid Measures. In making a Babcock test .equal quantities, by volume, of acid and milk are used. The acid measure, shown in Fig. 6, holds 17.5 c.c. of acid, the amount needed for one test.- The one shown in Fig. 7 is divided into six divisions, each of which holds 17.5 c.c. or one charge of acid. Where 28 CREAMERY BUTTER MAKING many tests are made a graduate of this kind saves time in filling, but should be made to hold twenty-five charges. H. A cream scales commonly used is illustrated in Fig. 8. Acid. The acid used in the test is commercial sul- Fig. 8. Cream scales. phuric acid having a specific gravity of 1 .82 to 1.83. When the specific gravity of the acid falls below 1.82 the milk solids are not properly burned and particles of curd may appear in the fat. On the other hand, an acid with a specific gravity above 1.83 has a tendency to blacken or char the fat. The sulphuric acid, besides burning the solids not fat, facilitates the separation of the fat by raising the specific gravity of the medium in which it floats. Sulphuric acid must be kept in glass bot- tles provided with glass stoppers. Exposure to the air materially weakens it. Making a Babcock Test. The different steps are indicated as follows : 1. Thoroughly mix the sample. 2. Immediately after mixing insert the pipette into the milk and suck until the milk has gone above the mark on the pipette, then quickly place the fore finger over the Fig. 9. Show- ing manner of emptying pi- pette. CREAMERY BUTTER MAKING 29 top and allow the milk to run down to the mark by slowly relieving the pressure of the finger. 3. Empty the milk into the bottle in the manner shown in Fig. 9. 4. Add the acid in the same manner in which the milk was emptied into the bottle. 5. Mix the acid with the milk by giving the bottle a slow rotary motion. 6. Allow mixture to stand a few minutes. 7. Shake or mix again and then place the bottle in the tester. 8. Run tester four minutes at the proper speed. 9. Add moderately hot water until contents come to the neck of the bottle. 10. Whirl one minute. 11. Add moderately hot water un- til contents of the bottle reach about the 8% mark. 12. Whirl one minute. 13. Leave tester open a few min- utes. 14. Read test. How to Read the Test. At the top of the fat column is usually quite a pronounced meniscus as shown in Fig. 10. A less pronounced one is found at the bottom of the column. The fat should be read from the extremes of the fat column, I to 3, not from 2 to 4, when its temperature is about 140 F. Too high a temperature gives too high Fig-. 10. -Fat column sbowingmeniscuses. 30 CREAMERY BUTTER MAKING a reading, because of the expanded condition of the fat, while too low a temperature gives an uncertain reading. Fig. 12. Miik bot- Fig. 11. Waste a^id jar. tie tester. Precautions in Making a Test. I. Be sure you have a fair sample. 2. The temperature of the milk should be about 60 or 70 degrees. 3. Always mix twice after acid has been added. 4. Be sure your tester runs at the right speed. CREAMERY BUTTER MAKING 31 5. Use nothing but clean, soft water in filling the bottles. 6. Be sure the tester does not jar. 7. Be sure the acid is of the right strength. 8. Mix as soon as acid is added to milk. 9. Do not allow the bottles to become cold before reading the test. 10. Read the test twice to insure a correct reading. The water added to the test bottles after they have been whirled should be clean and pure. Water containing much lime seriously affects the test. Such water may be used, however, when first treated with a few drops of sulphuric acid. As stated before skim-milk, buttermilk, and cream are tested in the same way as milk, with the exception that the cream sample is weighed not measured. Cleaning Test Bottles. As soon as the test is read, the bottle should be emptied into an earthen jar (covered with a perforated board) by shaking it up and down so as to remove the white sediment. (Fig. IT.) It is now rinsed with one-third pipetteful of cleaning solution, which is made by dissolving about an ounce of potassium bichromate in one pint of sulphuric acid. Next run test bottle brush once up and down the neck of the bottle and finally rinse with hot water. Testing or Calibrating Milk Bottles. Fill the bottle to the zero mark with water, or preferably wood alco- hol to which a little coloring matter has been added. Immerse the lower section of the tester, shown in Fig. 12, in the contents of the bottle. If the bottle is correct, the contents will rise to the $% mark. Next immerse both sections of the tester which will bring the contents to the 10% mark if the bottle is correctly calibrated. . ^.*****1&^ *>r THE ^ U N I VFDQITVl 32 CREAMERY BUTTER MAKING It has been learned that the volume of the graduated part of the neck is 2 c.c. Each section of the tester is made to displace i c.c. when immersed in the liquid, hence the two sections will just fill the scale if the latter is correct. Calculating Speed of Tester. The speed at which a tester must be run is dependent upon the diameter of the wheel carrying the bottles. The larger this wheel the fewer the revolutions it must make per minute to effect a complete separation of the fat. In the following table by Farrington and Woll the necessary speed per given diameter is calculated : Diameter of No. of revolutions wheel of zvheel in inches. per minute. 10 1,074 12 , ... 980 14..... 909 16 '... 848 18 800 20 ; 759 22 . 724 24 693 General Pointers. Black fat is caused by 1. Too strong acid. 2. Too much acid. 3. Too high a temperature of the acid or the milk. 4. Not mixing soon enough. 5. Dropping the acid through the milk. Foam on top of fat is caused by hard water, and can be prevented by adding a few drops .of sulphuric acid to the water. CREAMERY BUTTER MAKING 33 Unclean or cloudy fat is caused by 1. Insufficient mixing. 2. Too low speed of tester. 3. Too low temperature. 4. Too weak acid. Curd particles in fat are caused by 1. Too weak acid. 2. Not enough acid. 3. Too low temperature. CHAPTER III. I. THE LACTOMETER AND ITS USE. This instrument, shown in Fig. 13, is used to determine the specific gravity of milk. The stem has two scales upon it, a thermometer scale at the upper end and a lac- tometer scale at the lower. The latter scale reads from fifteen to forty, being divided into twenty-five divisions, each of which reads one lactometer degree. The lower end of the instrument consists of two bulbs : an upper one containing the mercury for the thermometer scale, and a lower and larger one weighted with shot or mercury which serves to immerse and to keep in an upright posi- tion the large oblong bulb or float below the stem. Making the Test. In making a lactometer test the sample of milk is carefully mixed and placed in the lactometer cylinder. (Fig. 14.) The lactometer is now carefully lowered into it and enough milk is added to the cylinder to fill it brim full. Now place your eye in a hori- zontal position with the surface of the liquid and read down as far as the liquid will permit. The reading thus obtained is the correct lactometer reading, provided the temperature as indicated by the thermometer scale is 60. Corrections for Temperature. Lactometers are stan- dardized at a temperature of 60 F. ; but, since it is diffi- cult to have a sample always at this temperature, cor- rections may be made for temperatures ranging from 50 to 70. As the temperature' rises the liquid expands and the specific gravity decreases. This decrease amounts to 34 CREAMERY BUTTER MAKING 35 one-tenth of a lactometer degree for every degree of tem- perature above 60. A decrease in temperature would result in a corresponding increase in the specific gravity. For every degree below 60, therefore, we subtract one- tenth degree from, and for every degree above 60 we Fig. 13. Lactom eter. Fig. 14. Lactom- eter cylinder. add one-tenth degree to, the lactometer reading. Ex- amples : 1. Lactometer reading is 32.5 at a temperature of 55. Corrected reading is 32.5 less .5, equals 32. 2. Lactometer reading is 31.7 at a temperature of 63. Corrected reading is 31.7 plus .3, equals 32. Interpretation of Lactometer Reading. In the chap- ter on milk we learned that normal milk has an average 36 CREAMERY BUTTER MAKING specific gravity of 1.032. This means that a tank that holds just i ,000 pounds of water would hold 1,032 pounds of milk. On the lactometer scale the i.o is omitted. A reading of 32, expressed in terms of specific gravity, would therefore read 1.032. Precautions in Making a Lactometer Test. I. A lactometer test should not be made until three or four hours after the milk leaves the udder of the cow. The reason for this is that milk, immediately after it is drawn, holds mechanically mixed with it air and probably other gases, which tends to give too low a reading. 2. The sample must be thoroughly mixed. If a layer of cream is allowed to form at the surface, the conse- quence is that the hollow oblong bulb will float in partially skimmed milk and give too high a reading. 3. A dirty lactometer is certain to give a false reading. A lactometer should be washed in luke warm (not hot) water to which a little soda or other alkali has been added, and then rinsed off with clean water and wiped. II. MILK SOLIDS. The solids of milk include^ everything but the water. If a sample of milk be kept at the boiling temperature until all the water is evaporated, the dry, solid residue that remains constitutes the solids of milk. It is con- venient to divide the solids into two classes, one inclu- ding all the fat, the other all the solids which are not fat. In referring, therefore, to the different solids of milk, we speak of the "fat" and the "solids not fat" which, to- gether, constitute the "total solids." The amount of each of these different solids present in milk is easily seen from the composition of milk. Thus, besides water, milk con- tains : CREAMERY BUTTER MAKING 37 3.9^ fat 2.9/fc casein 0.5^ albumen 4.9* sugar f = 9-*= solids not fat. 0.7^ ash Total I2.9^=total solids. Relationship of Fat and Solids not Fat. In normal milk a fairly definite relationship exists between the fat and the solids not fat. For example, milk rich in fat is likewise rich in solids not fat. On the other hand, milk poor in fat is also poor in solids not fat. As a general rule, an increase in the solids not fat always accompanies an increase in the percentage of fat. The increase is, however, not quite proportionate, the fat increasing the more rapidly. Since the casein represents the most valuable constitu- ent of the solids not fat, the following ratio between this substance and the fat very well illustrates the relation- ship that exists between the fat and solids not fat in milk : According to Van Slyke. Per cent fat. Per cent casein. 3.00 2.10 3.25 2.20 3-'50 2.30 3-75 2.40 4 . oo 2 . 50 4.25 2.60 4.50 2.70 Specific Gravity as Affected by Richness of Milk. The richness of milk seems to have but a very slight effect on its specific gravity. Usually a four per cent milk shows a slightly higher reading than a three per 38 CREAMERY BUTTER MAKING cent milk, but the specific gravity of a four per cent milk is practically the same as that of a four and one-half per cent milk. From what has been said about the relation- ship of the fat and solids not fat in milks of different richness, it is quite natural that the specific gravity of such milks should vary but little. If the fat alone were increased, the lactometer reading would naturally be de- pressed. But since the solids not fat increase in nearly the same proportion as the fat, the depression caused by the latter is compensated for by the former. Calculation of Milk Solids. The milk solids are cal- culated from the fat and the lactometer reading of milk. This is done by means of the following formula worked out at the Wisconsin Agricultural Experiment Station : Formula for solids not fat equals one-fourth L R plus one-fifth F, in which L stands for lactometer, R for reading, and F for fat. Expressed in another way, the solids not fat are obtained by adding one-fifth of the fat to one-fourth of the lactometer reading. The total solids are obtained by adding the fat to the solids not fat. Examples : 1. To calculate solids not fat when the milk shows a lactometer reading of 31.6 and fat reading of 3.5. Sub- stituting these figures for the letters in the formula, one- fourth L R plus one-fifth F, we get : / Ol f* O C v ( j plus -g-y equals (7.9 plus .7) equals 8.6 equals solids not fat. 2. The total solids in the above sample are obtained by adding the fat and solids not fat. Thus: 8.6 plus 3.5 equals 12.1 equals total solids. CREAMERY BUTTHR MAKING 39 III. DETECTION OF MILK ADULTERATION WATERING AND SKIMMING. A knowledge of the methods of detecting watering and skimming of milk is in many cases of considerable value to butter makers, even when the milk is bought on the fat basis. Where the milk is bought irrespective of its fat content, such a knowledge is simply indispensable for the welfare of the creamery. In normal milk ranging in fat from 3% to 5%, it is not difficult to detect a moderate amount of watering and skimming. We speak of normal milk because this means the milk from a full milking and excludes colostrum milk, milk from diseased cows and those far advanced in lacta- tion. Normal milk cannot be expected when cows are either only partially milked, diseased, or very far ad- vanced in lactation. The accuracy of determining the amount of watering and skimming becomes greater in proportion as the sam- ple represents more cows. " For example, no sample of rnilk from a herd consisting of six or more cows has been known to average below 3% fat. For this reason any sample of milk testing below 3%, when taken from a herd, is to be looked upon with suspicion. On the other hand there are records of individual cows that show tests as low as 1.7% and as high as 8%. It is owing to these extreme variations in the composition of milk from indi- vidual cows, that small amounts of adulteration cannot be estimated with the same degree of accuracy in such milk as in herd milk. Detection of Adulteration. The general procedure in determining whether milk has been watered or skimmed, or both, is as follows : 40 CREAMERY BUTTER MAKING 1. Determine the percentage of fat in the sample under consideration. 2. Determine its specific gravity. 3. From the fat and specific gravity calculate the solids not fat and total solids. 4. Compare the results obtained with the average specific gravity, per cent of fat, solids not fat, and total solids given for normal cows' milk, or compare with the legal State Standard. 5. In drawing conclusions remember that a. Fat is lighter than water. b. Milk is heavier than water. c. Skimming increases the lactometer reading. d. Skimming slightly increases solids not fat. e. Skimming decreases fat and total solids. f. Watering decreases fat, solids not fat, lac- tometer reading, and total solids. g. Watering and skimming decrease fat (ma- terially), solids not fat, and total solids. h. The solids not fat are less variable than the fat. i. Skimming and watering may give a normal lactometer reading. From i it is seen that a normal lactometer reading is possible when milk is skimmed and watered in the right proportions. A lactometer reading without a Babcock test is therefore worthless. For herd milk a lactometer reading above 33.5 is posi- tive evidence of skimming when accompanied with a low percentage of fat. Herd milk showing a lactometer read- ing below 28 is considered watered. Examples of milk adulteration in which only herd milk is considered are given as follows : CREAMERY BUTTER MAKING 41 i. Suspected sample shows: Normal milk shows: Lactometer reading 32 Lactometer reading 32 Fat 2.5 Fat 3.9 Solids not fat 8.5 Solids not fat 8.78 Total solids 11 .o Total solids 12.68 -Conclusion : Sample is watered and skimmed because (a) lactometer reading is normal and fat low; (b) solids not fat are nearly normal and total solids low. 2. Suspected sample shows : Lactometer reading . 33.2 Fat 3.1 Solids not fat 8.92 Total solids 12 . 02 Conclusion : Sample is skimmed because lactometer reading is high and fat low. 3. Suspected sample shows: Lactometer reading shows 29 Fat -....: 3.4 Solids not fat 7.93 Total solids n . 33 Conclusion : Sample is watered because everything is much below normal, which is to be expected in the case of watered milk. CHAPTER, IV. BACTERIA AND MILK FERMENTATIONS. A thorough knowledge of bacteria and their action forms the basis of success in butter making. Indeed the man who is lacking such knowledge is making butter in the dark ; his is chance work. Much attention will therefore be given to the study of these organisms in this work. I. BACTERIA. The term bacteria is applied to the smallest of living plants, which can be seen only under the highest powers of ths miscroscope. Each bacterium is made up of a single cell. These plants are so small that it would require 30,000 of them laid side by side to measure an inch. Their presence is almost universal, being found in the air, water, and soil ; in cold, hot, and temperate climates; and in living and dead as well as inorganic matter. Bacteria grow with marvelous rapidity. A single bac- terium is capable of reproducing itself a million times in twenty-four hours. They reproduce either by a simple division of the mother cell, thus producing two new cells, or by spore formation in which case the contents of the mother cell are formed into a round mass called a spore. These spores have the power of withstanding unfavorable conditions to a remarkable extent, some being able to endure a temperature of 212 F. for several hours. Most bacteria require for best growth a moist, warm, and nutritious medium such as is furnished by milk, in 42 CREAMERY BUTTER MAKING 43 which an exceedingly varied and active life is possible. In nature and in many of the arts and industries, bacteria are of the greatest utility, if not indispensable. They play a most important part in the disintegration of vegetable and animal matter, resolving compounds into their elemental constituents in which form they can again be built up and used as plant food. In the art of butter and cheese making bacteria are indispensable. The to- bacco, tanning, and a host of other industries cannot flourish without them. ii. MiivK FERMENTATIONS. Definition. In defining fermentation processes, Conn says that, "In general, they are progressive chemical changes taking place under the influence of certain organic substances which are present in very small quantity in the fermenting mass." With few exceptions, milk fermentations are the result of the growth and multiplication of various classes of bacteria. The souring of milk illustrates a typical fer- mentation, which is caused by the action of lactic acid bacteria upon the milk sugar breaking it up into lactic acid. Here the chemical change is conversion of sugar into lactic acid. . The most common fermentations of milk are the fol- lowing : [" Lactic. | Normal ..... -j Curdling and Digesting. [ Butyric. Milk Fermentations ^ ,- g. , Slimy or Ropy. Abnormal '< Gassy. | Toxic. [ Chromogenic. 44 CREAMERY BUTTER MAKING NORMAL FERMENTATIONS. We speak of normal fermentations because milk always contains certain classes of bacteria even when drawn and kept under cleanly conditions. These fermentations will be discussed in the following pages. I. LACTIC FERMENTATION. This is the most common and by far the most important fermentation of milk. Indeed it is indispensable in the manufacture of butter of the highest quality. The germ causing this fermentation is called Lactici Acidi. It is non-spore bearing and has its optimum growth tempera- ture between 90 and 98 F. At 40 its growth ceases. Exposed to a temperature of 140 for fifteen minutes it is killed. The souring of milk and cream, as already mentioned, is due to the action of the lactic acid bacteria upon the milk sugar changing it into lactic acid. Acid is therefore always produced at the expense of milk sugar. But the sugar is never all converted into acid because the pro- duction of acid is limited. When the acidity reaches about .9% the lactic acid bacteria are either checked or killed and the production of acid ceases. Owing to the universal presence of these bacteria it is almost impossible to secure milk free from them. Under cleanly conditions the lactic acid type of bacteria always predominates in milk. When, however, milk is drawn under uncleanly conditions the lactic organisms may be outnumbered, by other species of bacteria which give rise to the numerous taints often met with in milk. Contradictory as it may seem, the lactic acid bacteria are alike friend and foe to the butter maker. Creamery CREAMERY BUTTER MAKING 45 patrons are expected to have milk as free as possible from these germs so that it may arrive at the creamery in a sweet condition. They are therefore expected to thoroughly cool and care for it, not alone to suppress the action of the lactic acid bacteria but also that of the abnormal species that might have gained access to the milk. While the acid bacteria are objectionable in milk, in cream made into butter they are indispensable. The highly desirable aroma in butter is the result of the growth of these organisms in the process of cream ripening. There are a number of different species of bacteria that have the power of producing lactic acid. 2. CURDI.1XG AND DIGESTING FERMENTATION. In point of numbers this class of bacteria ranks perhaps next to the lactic acid type. Indeed it is very difficult to obtain milk that does not contain them. It is not often, however, that their presence is noticeable owing to their inability to thrive in an acid medium. According to bacteriologists most of these bacteria secrete two enzymes, one of which has the power of curdling milk, the other of digesting it. The former has the power of rennet, the latter of trypsin. "As a rule," says Russell, "any organism that possesses the digestive power, first causes a coagulation of the casein in a manner comparable to rennet." It is only occasionally when the lactic acid organisms are in a great minority, or when for some reason their action has been suppressed, that this class of bacteria manfests itself by curdling milk while sweet. The curd thus formed differs from that produced by lactic acid in being soft, and slimy. 46 CREAMERY BUTTER MAKING Most of the curdling and digesting bacteria are spore bearing and can thus withstand unfavorable conditions better than the lactic acid bacteria. For this reason milk- that has been heated sufficiently to kill the lactic acid bacteria, will often undergo the undesirable changes attributable to the digesting and curdling organisms.. 3. BUTYRIC FERMENTATION. It was mentioned that many bacteria have the power of producing lactic acid but that the true lactic acid fer- mentation is probably caused by a single species. So it is with the butyric acid bacteria. While a number of different organisms are known to produce this acid, Conn is of the opinion that the common butyric fermentation of milk and cream is due to a single species belonging to the anaerobic type. The butyric acid produced by these organisms is the chief cause of rancid flavors in cream and butter. These bacteria are widely distributed in nature, being particu- larly abundant in filth. They are almost universally present in milk, from which they are hard to eradicate on account of their resistant spores. It is on account of these spores and their ability to grow in the absence of oxygen that the butyric fermentation is often found in ordinary sterilized milk from which the air has been excluded. This class of bacteria has great significance in cream ripening and in the keeping quality of butter. In the ripening of cream the desirable flavor develops with the increase of acidity until the latter has reached .6%. When the development of acid goes beyond this, the flavor is no longer of the desirable kind but turns rancid as a result of the development of the butyric fermentation. U N I V t RS CREAMERY BUTTER MAKING 47 The butyric fermentation is rarely noticeable during the early stage of cream ripening and its subsequent development in a highly acid cream is explained by Russell as being "probably due, not so much to the pres- ence of lactic acid, as to the absence of dissolved oxygen, which at this stage has been used up by the lactic acid organisms." Butter that is apparently good in quality when freshly made, will usually turn rancid when kept at ordinary temperatures a short time. The quickness with which this change comes is dependent largely upon the amount of acid present in cream at the time of churning. Butter made from cream in which the maximum amount of acid consistent with good flavor has been developed, usually possesses poor keeping quality. This seems to indi- cate that at least part of the rancidity that develops in butter after it is made is due to the butyric acid bacteria, while light and air, doubtless, also contribute much to this end. ABNORMAL FERMENTATIONS. No trouble needs to be anticipated from these fermenta- tions so long as cleanliness prevails in the dairy. The bacteria that belong to this class are usually associated with filth, and dairies that become infested with them show a lack of cleanliness in the care and handling of the milk. Since milk is frequently infected with one or another of these abnormal fermentations a brief discus- sion will be given of the most important. i. BITTER FERMENTATION. Bitter milk and cream are quite common and there are several ways in which this bitterness is imparted : it may 48 CREAMERY BUTTER MAKING be due to strippers' milk and to certain classes of feeds and weeds, but most frequently to bacteria. This class of bacteria has not yet been studied very thoroughly but we know a great deal about it in a practical way. In milk and cream in which the action of the lactic acid germs has been suppressed by low temperatures, bitter- ness due to the development of the bitter fermentation is almost certain to be noticeable. When the temperature is such as to cause a rapid development of the lactic fermentation, the bitter fermentation is rarely, if ever, present. It is quite evident from this that the bitter organisms are capable of growing at much lower tem- peratures than the lactic and that so long as the latter are rapidly growing the bitter fermentation is held in check. This teaches us that it is not safe to ripen cream below 60 F. The author has found that cream quickly ripened and then held at a temperature of 45 for twenty-four hours would show no' tendency toward bitterness, while the same cream held sweet at 45 for twenty- four hours and then ripened would develop a bitter flavor. This indicates that the lactic acid is unfavorable to the develop- ment of the bitter fermentation. The bitter germs produce spores capable of resisting the boijing temperature. This accounts for the bitter taste that often develops in boiled milk. 2. SUMY OR ROPY FERMENTATION. This is not a common fermentation and rarely causes trouble where cleanliness is practiced in the dairy. The bacteria that produce it are usually found in impure water, dust, and dung. These germs are antagonistic to CREAMERY BUTTER MAKING 49 the lactic organisms and for this reason milk infected with them sours with great difficulty. The action of this class of bacteria is to increase the viscosity of milk, which in mild cases simply assumes a slimy appearance. In extreme cases, however, the milk develops into a ropy consistency, permitting it to be strung out in threads several feet long. Slimy or ropy milk cannot be creamed and is therefore worthless in the manufacture of butter. Such milk should not be confused with gargety milk which is stringy when drawn from the cow. The bacteria belonging to this class are easily destroyed as they do not form spores. 3. GASSY FERMENTATION. This is an exceedingly troublesome fermentation in cheese making and is also the cause of much poor flavored butter. The gas germs are very abundant during the warm summer months but are scarcely noticeable in winter. Like the bitter germs, they are antagonistic to the lactic acid bacteria and do not grow during the rapid development of the latter. They are found most abun- dantly in the barn, particularly in dung. 4. TOXIC FERMENTATIONS. Toxic or poisonous products are occasionally developed in milk as a result of bacterial activity. They are most commonly found in milk that has been kept for some time at low temperature. 5. CHROMOGENIC FERMENTATIONS. Bacteria belonging to this class have the power of imparting to milk various colors. The most common of 50 CREAMERY BUTTER MAKING these is blue. It is, however, not often met with in dairy practice since the color usually does not appear until the milk is several* days old. The specific organism that causes blue milk has been known for more than half a century and is called cyanogenous. Another color that rarely turns up in dairy practice is produced by a germ known as prodigiosis, causing milk to turn red. Other colors are produced such as yellow, green, and black, but these are of very rare occurrence. Fig. 15. Composite test jar. CHAPTER V. COMPOSITE SAMPLING. Where milk is bought on the fat basis, it is essential that it be sampled daily as it arrives at the creamery. It is not practicable, however, to make daily tests of the samples because this would involve too much work. Each patron is therefore provided with a pint jar to which samples of his milk are added daily for one or two weeks, the sample thus secured being called a composite sample. A test of this composite sample represents the average percentage of butter fat in the milk for the period during which the sample was gathered. Careful experiments have shown that quite as accurate results can be obtained with the composite method of testing as is possible by daily tests, besides saving a great deal of work. This has lead to its universal adoption wherever milk is bought by the Babcock test. All composite jars should be carefully labeled by plac- ing numbers upon them. These numbers should be writ- ten in large indelible figures as exhibited by the composite jar shown in Fig. 15. Shelves are provided in the intake upon which the jars are arranged in regular consecutive order. Numbers corresponding to those on the jars are placed on the milk sheet opposite the names of the patrons which should be arranged alphabetically. Taking the Samples. Whatever the method of sam- pling, all milk should be sampled immediately after it enters the weigh can, not, as is frequently the case, after it is weighed. 51 52 CREAMERY BUTTER MAKING Most of the sampling is done by either of two methods : (i) by means of a half ounce dipper, shown in Fig. 16, or (2) by means of long narrow tubes, one of which is shown in Fig. 17. The dipper furnishes a simple and easy means of sampling milk. Where the milk is thoroughly mixed, and the variations in quantity from day to day are slight, the dipper method of sampling is accurate. The other method of sampling is illustrated by the Scovell sampler (Fig. 17). The main tube of the sampler is open at both ends, the lower of which closely fits into a cap provided with three elliptical openings. As the sampler is lowered into the milk the latter rushes through the openings filling the tube to the height of the milk in the can. When the cap strikes the bottom of the can the tube slides over the openings, thus permitting the sample to be withdrawn and emptied into the composite jar. This sampler has the advantage of always taking an aliquot portion of the milk, and furnishing an accurate sample when the sampling is somewhat delayed, because it takes as much milk from the top as it does from the bottom of the can. The Equity sampler designed by Kolarik, works on the same principle as the Scovell and has proven very satis- factory. Preservatives. Milk cannot be satisfactorily tested after it has loppered owing to thhe difficulty of securing an accurate sample. This makes it necessary to add some preservative to the composite samples to keep them sweet. The best preservatives for this purpose are corrosive sublimate, formalin, and bichromate of potash. All of these are poisons and care must be taken to place them CREAMERY BUTTER MAKING 53 Fig. 16. Milk sampler. Fig 17 Scovell sampling tube. where children, and others unfamiliar with their poison- ous properties, can not have access to them. The bichromate of potash and corrosive sublimate can be purchased in tablet form, each tablet containing enough preservative to keep a pint of milk sweet for about two 54 CREAMERY BUTTER MAKIXG weeks. The tablets color the milk so that there can be no mistake about its unfitness for consumption. When colorless preservatives are used, like ordinary formalin and corrosive sublimate, a little analine dye should be added to prevent mistaking the identity of milk treated with these preservatives. During the warm summer time the bichromate of potash is not as satisfactory as either of the other two preservatives mentioned, because of its comparative weak- ness and liability to interfere with the test when too much of it is used. When the bichromate is used in the ordi- nary solid form not more than a piece the size of a pea should be used, otherwise a good, clear test is not possible. For spring, fall, and winter use, however, bichromate of potash is excelled by no other preservative, either in cheapness, or safety and convenience in handling. Care of Composite Samples. It is a duty which the butter maker owes his patrons to keep the sample jars carefully locked up when not in use so as to prevent the possibility of anyone's tampering with them. This will serve the additional purpose of excluding the light from the samples, for they will keep but a short time when exposed to light and heat. When the sample jars are permitted to stand a few days without shaking, the cream which rises will dry and harden, especially that in contact with the sides of the jar, so that it becomes difficult to secure a fair sample on testing day without special treatment of the sample. This is prevented by giving the jar a rotary motion every time a sample of milk is added. It is important, too, that the covers of the jars fit tight, otherwise evaporation takes place, resulting in an in- creased test. In several instances the author has ob- CREAMERY BUTTER MAKING 55 served that the butter maker (?) did not cover the jars at all ! Can we wonder why patrons complain so fre- quently about the testing? Where the jars are kept uncovered for several weeks the cream is in a condition in which it can not be reincorporated with the milk and the Babcock test in this case becomes truly a snare and delusion. Should the samples show any dried or churned cream on testing day, the sample jars must be placed in \vater at a temperature of 110 F. for five or ten minutes to allow the cream or butter to melt. When this is done the sample for the test bottle must be taken instantly after mixing, as the melted fat separates very quickly. Frequency of Testing. It must not be supposed' that if enough preservative can be added to the sample jars to keep the milk sweet for a month or longer that it is just as well to make monthly tests as weekly. Far from it. Even if the milk does remain sweet, the tendency of the cream to churn and become dried and crusty is in itself sufficient protest against monthly testing. It is rare, indeed, that samples that have been kept for a month or longer can be sampled satisfactorily without warming them in a water bath, which means a great deal of extra work. The best tests are secured when the samples are tested weekly or at most every two weeks. When the tests are made weekly it rarely becomes necessary to warm the samples if they have been properly cared for. Then, too, if an error is made anywhere in the testing, there are three other tests for the month that help to mini- mize it. It is not strange at all that a sample jar should break occasionally. If the jar should contain a whole month's milk the patron is deprived of his test for 56 CREAMERY BUTTER MAKING that month. On the weekly basis of testing there would still be three tests to fall back on. Supervision of Test. To relieve the butter maker from any suspicion of unfairness or carelessness in the testing of the composite samples, one or two of the patrons should be present at each testing. When one of the patrons thus witnesses the details of the testing and is furnished with a copy of the test, the butter maker is practically exempt from the suspicions that usually rest upon him, no matter how honest or careful a man he may be. Duplicate Set of Jars. Where the testing is not under the supervision of one of the patrons, some butter makers have adopted the scheme of providing a double set of sample jars. After the test is made the jars, instead of being emptied, are set aside for a week, so that any- one who has any complaint to offer on the test may call on the buttermaker for a retest, another set of sample jars being used in the meantime. CHAPTER VI. CREAMING. Definition. Milk upon standing soon separates into two portions, one called cream, the other skim-milk. This process of separation is known as creaming, and is due to the difference in the specific gravity of the fat and the milk serum. The fat being light and insoluble, rises, carrying with it the other constituents in about the same proportion in which they are found in milk. The fat together with these other constituents forms the cream. After the cream has been skimmed off, there remains a more or less fat- free watery portion called skim-milk. Processes of Creaming. The processes by which milk is creamed may be divided into two general classes : ( i ) that in which milk is placed in shallow pans or long narrow cans and allowed to set for about twenty-four hours,, a process known as natural or gravity creaming; (2) that in which gravity is aided by subjecting the milk to centrifugal force, a process known as ceritrifugal creaming. The centrifugal force has the effect of increas- ing the force of gravity many thousands of times, thus causing an almost instantaneous creaming. This force is generated in the cream separator. Before the days of the centrifugal cream separator, creameries either bought the milk and creamed it at the creamery by the gravity process, or bought and gathered the cream that had been creamed at the farms by the same process, The method of cream gathering is still exten- sively employed by creameries ; indeed in many sections 57 58 CREAMERY BUTTER MAKING of the country this practice is actually growing. Cream thus gathered is, however, largely the product of the cream separator, only a small portion being still creamed by the gravity process. The discussion on creaming will therefore be confined to the centrifugal process. CREAM SEPARATORS. History. The cream separator had its beginning in 1864 when Prandtl, of Munich, creamed milk by means of two cylindrical buckets revolving upon a spindle. In 1874 Lefeldt constructed a separator with a revolving drum similar to the later hollow bowl separators. This drum had a speed of 800 revolutions per minute. But it lacked an arrangement permitting a continuous discharge of cream and skim-milk, so that the separator had to be stopped at regular intervals when the cream was skimmed off, the skim-milk removed, and the bowl refilled for the next separation. It was not until 1879 that real separators appeared upon the market. During this year two machines were perfected which permitted continuous cream and skim- milk discharges. One was known as the Danish Weston, invented in Denmark, the other the De Laval, invented in Sweden. Both of these separators were hollow bowl machines. Other separators soon followed but no decided improve- ment was made until 1891, when the De Laval separator, shown in Fig. 18, appeared with a series of discs inside the bowl which had the effect of separating the milk in thin layers, thus increasing both the efficiency and the capacity of the separator. Since then various bowl devices have been invented by numerous separator manufacturers. CREAMERY BUTTER MAKING 59 In 1896 a hollow bowl separator was again placed upon the market, this time by the Sharpies Company. This separator had a long, narrow, suspended bowl, revolving about 24,000 times per minute, in which the efficiency of skimming was greater than that in the old hollow bowl style of separators. Fig. 18. De Laval cream separator. Fig. 19. Sharpies crecm separator. In 1902 this company introduced another separator with a bowl of about the same construction but filled with a core made up of numerous sections which allowed the speed to be reduced to 14,000 revolutions per min- ute. This is a turbine separator a cut of which is shown in Fig. 19. Numerous other power separators have been in use for many years, chief among which may be mentioned the United States and Reid. 60 CREAMERY BUTTER MAKING Hand separators first appeared on the market in 1886. They are extensively used on dairy farms at the present time and are rapidly replacing the gravity methods of creaming. In 1887 a machine appeared on the market which ex- tracted the butter directly from sweet milk. This machine was called butter extractor. The butter made with the extractor was inferior in quality and the machine has practically gone out of existence. Choice of Separator. In choosing a cream separator we should be guided by three things : i . Efficiency of skimming; 2.. Power required to operate; 3. Its durability. I. EFFICIENCY OF SKIMMING. Under favorable conditions a separator should not leave more than .05% fat in the skim-milk by the Babcock test. There are a number of conditions that affect the efficiency of skimming and these must be duly considered in making a separator test. The following are some of these con- ditions : A. Speed of bowl. B. Steadiness of motion. C. Temperature of milk. D. Manner of heating milk. E. Amount of milk skimmed per hour. F. Acidity of milk. G. Viscosity of milk. H. Richness of cream. I. Stage of lactation. (Stripper's milk.) A. The greater the speed the more efficient the cream- ing, other conditions the same. It is important to see CREAMERY BUTTER MAKING 61 that the separator runs at* full speed during the separating process. The speed indicator should always be applied before turning on the milk and several times during the run. Loose belts, pulleys slipping on the shaft, and low steam pressure will reduce the speed of the separator. 1). A separator should run as smoothly as a top. The slightest trembling will increase the loss of fat in the skim-milk. Trembling of bowl may be caused by any of the following conditions: (i) loose bearings, (2) sepa- rator out of plum, (3) dirty oil or dirty bearings, (4) un- stable foundation, or (5) unbalanced bowl. C. The best skimming is not possible with any sepa- rator when the temperature falls below 60 F. A tem- perature of 85 F. is the most satisfactory for ordinary skimming. Under some conditions the cleanest skimming is obtained at temperatures above 100 F. The reason milk separates better at the higher temperatures is that the viscosity is reduced. D. Sudden heating tends to increase the loss of fat in skim-milk in ordinary skimming. The reason for this is that the fat heats more slowly than the milk serum which diminishes the difference between their densities. When, for example, milk is suddenly heated from near the freezing temperature to 85 F. by applying live steam, the loss of fat in the skim-milk may be four times as great as it is under favorable conditions. If, instead of suddenly heating the milk to 85, it is heated to 160 or above, then no extra loss of fat occurs. Hence the ad- vantage of separating milk at pasteurizing temperature during the winter. E. Unduly crowding a separator increases the loss of fat in the skim-milk. On the other hand, a marked underfeeding is apt to lead to the same result. 62 CRLIAMHRY BUTTHR MAKING F. The higher the acidity of milk the poorer the creaming. With sour milk the loss of fat in the skim- milk becomes very great. This emphasizes the importance of having the milk delivered to the creamery in a sweet condition. G. Sometimes large numbers of undesirable (slimy) bacteria find entrance into milk and materially increase its viscosity. This results in very unsatisfactory creaming. Low temperatures also increase the viscosity of milk which accounts for the poor skimming at these tempera- tures. H. Most of the standard makes of separators will do satisfactory work when delivering cream of a richness of $0%: A richer cream is liable to result in a richer skim- milk. The reason for this is that in rich cream the skim-milk is taken close to the cream line where the skim- milk is richest. I. Owing to the very small size of the fat globules in stripper's milk, such milk is more difficult to cream than that produced in the early period of lactation. 2. POWER REQUIRED TO OPERATE. This is a matter of importance as a heavy running machine will add much to the running expenses of the creamery. Such a machine will not only require more fuel but will increase the wear of belts and machinery. 3. DURABILITY. Cream separators are expensive machines and due re- gard should be given to their wearing qualities. They should be made of the best material, possess good work- manship, and have as few wearable parts as possible. CREAMERY BUTTER MAKING 63 SEPARATING TEMPERATURE;. During the summer time, when milk is fresh and re- quires little heating, a separating temperature of 70 F. gives good results. In the late fall and during the winter, when milk is received cold and often two days old, it is necessary to raise the temperature of the milk to 85 before separating. When milk is received in a partly frozen condition or when permeated with bad odors, a separating temperature of 140 to 170 is pre- ferred. Whenever such high temperatures are employed it is necessary to cool the cream immediately after it leaves the separator to a temperature of 70 or lower. RICHNESS OF CREAM. How Regulated. The richness of cream is usually regulated by means of a cream screw in the separator bowl. When a rich cream is desired the opening in the screw is turned toward the center of the bowl, and for a thin cream it is turned away from the center. In some machines the richness of cream is regulated by the rate of separation. With all separators the more milk separated per hour and the lower the speed the thinner the cream. Too low a speed always results in a rich skim-milk and poor cream. Temperatures between 60 and 90 have little effect on the richness of cream. W T hen, however, the tempera- ture is raised to 140 or above , the cream becomes thinner. Advantages of Rich Cream. These may be summed up as follows : 1. Permits t4ie use of more starter. 2. Contains fewer objectionable bacteria. 64 CREAMERY BUTTER MAKING 3. Can be churned at a lower temperature. 4. Occupies less space. 5. There is less cream to cool. Where a large amount of starter is to be added to the cream it is necessary to separate a rich cream so that the starter will not bring it below the churning richness. Fig. 20. -Cmtis milk heater. In case milk is tainted it is desirable to separate a very heavy cream so as to get rid of as much milk serum as possible. In this way we get rid of most of the taint, which develops in the milk serum. The cream is then reduced to churning richness with starter, or partly with starter and partly with fine flavored milk. The fat globules in a rich cream are close together which permits churning at a comparatively low tempera- ture. The chief advantage gained in this is the greater exhaustiveness of churning. CREAMERY BUTTER MAKING 65 MILK HEATERS. There are to be found upon the market two general classes of milk heaters : Those which admit the steam directly to the milk called direct heaters, and those in which the steam enters a jacket surrounding the milk known as indirect heaters. Direct Heaters. These are practically nothing more than an expansion in the feed pipe in which the steam \/\ Fiir 21. Twentieth Century milk heater. enters the milk. They are permissible only when first class steam is available and when milk is to be heated through a short range of temperature. But even under these conditions indirect heaters are always preferred. The two main objections to the direct heaters are: (i) the liability of contaminating the milk with impure steam, and (2) the effect of the sudden heating upon the loss of fat in the skim-milk which may be quite considerable when the milk is heated through a long range of temperature. Indirect Heaters. Figs. 20 and 21 illustrate this type of heaters. In the Curtis heater the milk circulates in a CREAMERY BUTTER MAKING thin sheet between an inner removable cylinder and the inner wall of the steam jacket, thus heating it gradually as it passes from one end to the other. In the Twentieth Fig. 22. Reid pasteurizer. Fig. 23. Bair cream cooler. Century heater the steam passes inside a series of discs. These discs are in motion during the heating and force the milk into the separator. Another type of indirect heater is the Reid pasteurizer shown in Fig. 22. This machine not only heats the milk but elevates it, thus dis- pensing with the use of a milk pump. CREAMERY BUTTER MAKING 67 CREAM COOLERS. With the modern cream ripeners described in Chapter VII no special cream cooler is necessary since the cooling is very quickly done in the ripener. With open vats placed on the same floor with the separators the most practical cooler is that belonging to the Bair type, which is illustrated in Fig. 23. This cooler is from six to eight feet long, about one foot wide, and three inches deep. The top of the cream vat need there- fore not be more than four inches lower than the cream spout of the separator. The circulation of the water is indicated by the arrows, the water entering the cooler at the point at which the cream leaves it. The surface over which the cream flows is slightly corrugated, thus increasing the amount of cooling surface. This cooler will cool cream within ten degrees of the temperature of the water when separated at ordinary temperatures. CHAPTER VII. CREAM RIPENING. This chapter will be discussed under three heads : Part I. Theory and Methods of Cream Ripening. Part II. The Control of the Ripening Process. Part III. Cream Acid Tests. PART i. THEORY AND METHODS OF CREAM RIPENING. Cream ripening is a process of fermentation in which the lactic acid organisms play the chief role. In every-day language, cream ripening means the souring of the cream. So important is this process that the success or failure of the butter maker is largely determined by his ability to exercise the proper control over it. In common creamery practice the time consumed in the ripening of cream varies from six to twenty- four hours and includes all the changes which the cream undergoes from the time it leaves the -separator to the time it enters the churn. Object. The ripening of cream has for its prime object the development of flavor and aroma in butter, two qualities usually expressed by the word flavor. In addition to this, cream ripening has several minor pur- poses, namely : ( i ) renders cream more easily churnable ; (2) obviates difficulties from frothing or foaming in churning; (3) permits a higher churning temperature ; (4) increases the keeping quality of butter. Flavor, This, so far as known at the present time, 68 Y BUTTUR M.IKIXU 69 is the result of the development of the lactic fermentation. If other fermentations aid in the production of this im- portant quality of butter, they must he looked upon as secondary. In practice the degree or intensity of flavor is easily controlled by governing the formation of lactic acid. That is, the flavor develops gradually with the increase in the acidity of the cream. Sweet cream butter for example is almost entirely devoid of flavor, while cream with an average richness possesses the maximum amount of good flavor possible when the acidity has reached .6%. From this it might appear that all of the flavor is inher- ent in the lactic acid itself. But this is not the case. The souring of milk free from fat does not produce the flavor found in sour cream, though the acid is the same in both cases. The view held by Duclaux is perhaps the most satisfactory in explaining the origin of the flavor produced in cream ripening. He maintains that since some caproic and butyric acids always exist in a free state in butter, the flavor may be the result of the forma- tion of caproic and butyric ethers from these acids. The formation of such ether compounds in cream would doubtless be due to the presence of lactic acid. And it can not be denied that the lactic acid itself figures as one of the components of butter flavor. Churnability. Practical experience shows that sour cream is more easily churnable than sweet cream. This is explained by the fact that the development of acid in cream tends to diminish its viscosity. The concussion pro- duced in churning causes the little microscopic fat glob- ules to flow together and coalesce, ultimately forming the small granules of butter visible in the churn. A high viscosity impedes the movement of these globules. It is 70 CREAMERY BUTTER MAKING evident, therefore, that anything that reduces the viscosity of cream, will facilitate the churning. As a rule, too, the greater the churnability of cream the smaller the loss of fat in the buttermilk. Frothing. Experience shows that ripened cream is less subject to frothing or foaming than unripened. This is probably due to the reduced viscosity of ripened cream and the consequent greater churnability of same. Temperature. Sour cream can be churned at higher temperatures than sweet cream with less loss of fat in the buttermilk. This is of great practical importance since it would be difficult, if not impossible, for most creameries to get low enough temperatures for the suc- cessful churning of sweet cream. Indeed, many cream- eries fail to get a low enough churning temperature for ripened cream. Keeping Quality. It has been found that butter with the best keeping quality is obtained from well ripened cream. It is true, however, that butter made from cream that has been ripened a little too far will posesss very poor keeping quality. An acidity of .5% should be placed as the limit when good keeping quality is desired. METHODS OF CREAM RIPENING. There are three ways in which cream is ripened at the present time : 1. By the unaided development of the lactic fermenta- tion called natural ripening. 2. By first destroying the bulk of the bacteria in cream by heat and then inoculating same with cultures of lactic acid bacteria. This method is known as pasteurized cream ripening. CREAMERY BUTTER M.IK IXC 71 3. By the aided development of the lactic fermenta- tion called starter ripening. I. NATURAL RIPENING. By this is meant the natural souring of the cream. In this method no attempt is made to repress the abnormal fermentations or to assist in the development of the lactic. From the chapter on Milk Fermentations we have learned that milk normally contains a number of different kinds of germs, frequently as many as a dozen or more. Natur- ally, therefore, where this method of ripening is practiced, a number of fermentations must go on simultaneously and the flavor of the butter is impaired to the extent to which the abnormal fermentations have developed. If the cream is clean and uncontaminated the lactic fermentation greatly predominates and the resulting flavor is good. If, on the other hand, the cream happens to contain many bad germs the probability is that the abnormal ferments will predominate and the flavor of the butter will be badly "ofL" Where cream is therefore allowed to take its own course in ripening the quality of the butter is a great uncertainty. This method, though still practiced by many butter mak- ers, is to be condemned as obsolete and unsatisfactory. 2. PASTEURIZED CREAM RIPENING. Theoretically and practically the ideal way of making butter is to pasteurize the cream, a process which consists in heating cream momentarily to a temperature of 160 to 185 F. and then quickly cooling to 60 F. In this manner most of the bacteria in the cream are destroyed. After this treatment the cream is heavily inoculated with the lactic acid bacteria, and the lactic fermentation is given 72 CREAMHRY BUTTlUt MAKING a favorable temperature for development. When cream is treated in this way the lactic fermentation is practically the only one present and a butter with the desirable flavor and aroma is the result. It is the only way in which a uniform quality of butter can be secured from day to day. This system of cream ripening is almost universally fol- lowed in Denmark, whose butter is recognized in all the world's markets as possessing qualities of superior excel- lence. The method is also gradually gaining favor in America and its general adoption can only be a matter of time. In the chapter on Cream Pasteurization this method is discussed in detail. 3. STARTER RIPENING. This method of ripening consists in adding "starters/' or carefully selected sour milk, to the cream after it -leaves the separator. A full discussion of starters will be found in the following chapter. In America this is at present the most popular method of cream ripening. While it does not, and can not, give the uniformly good results obtained by pasteurizing the cream, it is far superior to natural or unaided ripening. When we have a substance which contains many kinds of bacteria, there naturally follows a struggle for exist- ence and the fittest of the species will predominate. We always have a number of different types of bacteria in cream, both desirable and undesirable. The latter can be held in check by making the conditions as favorable as possible for the former.. Fortunately, when milk is properly cared for the latic acid germs always pre- dominate. But where milk is received at the creamery from 30 to 200 patrons, undesirable germs are frequently present in such large numbers as to seriously endanger Ml'MY BUTTER MAKJXG 73 the growth of the lactic acid bacteria. However, when a large amount of starter containing only lactic acid germs is added to the cream from such milk these organisms arc 4 certain to predominate. The best results with the starter method are secured when the milk is received at the creamery in a sweet condition and when a large amount of starter is used. Generally when milk is received in a sweet condition, especially during the summer months, it indicates that it has been thoroughly cooled and that the germs are present only in small numbers. When the cream from such milk is heavily inoculated with lactic acid germs by adding a starter, the development of the lactic fermenta- tion is so rapid as to either check or entirely suppress the action of undesirable bacteria that may be present in the cream. PART II. THE; CONTROL OF THE RIPENING PROCESS. In Part I an attempt was made to convey some idea as to our present theory and methods of cream ripening. We learned that the highly desirable flavor and aroma of butter are produced by the development of the lactic fermentation. In the following discussion we shall take up the means of controlling this fermentation and treat of the more mechanical side of -cream ripening. This will include: i. The time the starter should be added to the cream ; 2. The amount of starter to be added ; 3. The ripening temperature; 4. Time in ripening; 5. Agitation of cream during ripening ; 6. Means of controlling tem- perature. i. The value of a starter in cream ripening has already been made evident in the discussion of the theory of cream ripening. To secure the maximum effect of a starter it should be added to the cream vat soon after the separation 74 of the milk has begun but not until the cream has reached a temperature of 70 F. The cream thus coming in con- tact with the starter as it leaves the separator insures a vigorous development of the starter germs, so that by the time the separation is completed, the starter fermentation is almost certain to predominate, especially when a large amount of starter is used. 2. The maximum amount of starter that may be con- sistently used is one pound to two pounds of cream. A larger amount than this would be liable to result in too thin a cream. Experience teaches us that the maxi- mum richness of cream permissible in clean skimming under average conditions is 50%. Adding one pound of starter to two pounds of such cream would give us a 33 T ~3 % cream, the ideal richness for churning. But this amount of starter is rarely permissible on account of the poor facilities for controlling the temperature of the cream. 3. Since the lactic acid bacteria develop best at a temperature of 90 to 98 F. it would seem desirable to ripen cream at these temperatures. But this is not practicable because of the unfavorable effect of high tem- peratures on the body of the cream and the butter. Good butter can be produced, however, under a wide range of ripening temperatures. The limits may be placed at 60 and 80. Temperatures below 60 are too unfavorable for the development of the lactic acid bacteria. Any check upon the growth of these germs increases the chances for the development of other kinds of bacteria. l>ut it may be added that when cream has reached an acidity of .4% or more, the ripening may be finished at a temperature between 55 and 60 with good results. In general practice a temperature between 60 and 70 gives CREAMERY BUTTER MAKING 75 the best results. This means that the main portion of the ripening is done at this temperature. The ripening is always finished at temperatures lower than this. 4. As a rule quick ripening gives better results than slow. The reason for this is evident. Quick ripening means a rapid development of the lactic fermentation and, therefore, a relatively slow development of other fer- mentations. Practical experience shows us that the growth of the undesirable germs is slow in proportion as that of the lactic is rapid. For instance, when we attempt to ripen cream at 55 F., a temperature unfavor- able for the growth of the lactic acid bacteria, a more or less bitter flavor is always the result. This is so because the bitter germs develop better at low tempera- tures than the lactic acid bacteria. The main portion of the ripening should be done in about six hours. After this the temperature should be gradually reduced to a point at which the cream will not overripen before churning. 5. It is very essential in cream ripening to agitate the cream frequently to insure uniform ripening. When cream remains undisturbed for some time the fat rises in the same way that it does in milk, though in a less marked degree. The result is that the upper layers are richer than the lower and will sour less rapidly, since the action of the lactic acid germs is greater in thin than in rich cream. This uneven ripening leads to a poor bodied cream. Instead of being smooth and glossy, it will appear coarse and curdy when poured from a dipper. The im- portance of stirring frequently during ripening should therefore not be underestimated. 6. The subject of cream cooling is a very important 76 CREAMERY BUTTER MAKING one and will be discussed under the head of cream ripeners. CREAM RIPENERS. During the summer months much butter of - inferior quality is made by overripening the cream and churning at too high a temperature. This is due chiefly to a lack of proper cool- ing facilities. With the open cream vats the Fig. M .-Bo,a cream ripencr. contro ) of temperature is a difficult thing. For- tunately these vats are being replaced by the more modern cream ripeners of which the Farrington and the Boyd are Fig. 25. Farrington cream ripener. CREAMERY BUTTER MAKING 77 types. These ripeners possess two important advantages over the open vats, namely : first, they permit a more rapid cooling by agitating the water and cream while cooling ; "second, they maintain a more uniform temperature be- cause of tight fitting covers and better all round construc- tion. With "the Boyd ripener, shown in Fig. 24, the cooling is done by running cold water through a series of tinned-iron pipes which are inserted in the cream and kept moving to and fro by means of power attachment. The cooling in the Farrington vat is accomplished by circulating cold water in a jacket surrounding the cream. The vat is of cylindrical shape and is ro- tated by power during cooling. The Farrington ripener and air com- pressor for forcing the cream into the churn are shown in Figs. 25 and 26. Since these ripeners are so con- structed as to render the addition of ice to the water in them im- possible, they can not be considered complete without an ice water at- tachment. In Fig. 27 an ice water tank may be seen attached to the Boyd ripener. Ice water may be circulated in the same way with the Farrington ripener. Tank A contains ice water which is kept circulating through the ripener by means of pump B. By using the water over and over again, only a very small quantity Fig. 26. Air compressor. 78 CREAMERY BUTTER MAKING of ice is required in cooling cream to the desired tempera- ture. When the great cooling power of ice is once fully understood it is easy to see what a great amount of cooling a small quantity of ice will do. One pound of ice in melting will give out 140 times as much cold as Fig. 27. Showing method of circulating ice water through ripener. one pound of water raised from 32 to 33 F. In other words, the cooling power of ice is 140 times as great as that of water. To get at the amount of ice necessary in cooling cream with ice a series of tests was made with a 400 gallon Farrington ripener, which was carried out as follows : As soon as about thirty-five gallons of cream was sepa- rated, the ripener was set in motion and a continuous stream of cold water kept flowing through it until all the cream was separated. Further cooling was then de- layed for three or four hours when the ripener was again started and iced water allowed to circulate through it by means of a common rotary pump. The results thus secured are set forth in the following table : CREAMERY BUTTER MAKING 79 Results obtained with a 400 gallon Harrington Cream Ripener. COOLING WITH ICED WATER. Gallons cream. Initial temper- a t ur e of cream. Lnitial tem- perature of water. Final t e m- perature of cream. F ina 1 t e m- perature of water. Amount of ice used, Ibs. Time run. Temperature of cream in morning. Temperature of water in morning. 260. 64 58 53 53 100 45min. 57 60 260 58 58 54 53 94 45 58 62 260 2(50 64 61 58 58 54 55 52 54 105 140 35 45 58 57 62 60 260 .. 59 60 52 48 110 35 58 61 260 60 58 55 52 120 40 260 59 60 53 53 100 40 58 62 260. 58 60 55 53 70 30 260 66 58 55 53 100 45 COO 60' 260 58 59 52 50 80 30 58 58 260 58 58 53 51 75 30 59 ' 60 260. . .. 62 58 54 52 100 40 58 3 59 Attention is called to the large amount of cream cooled in these experiments. The 260 gallons of cream repre- sented about 20,000 pounds of milk. Moreover, it must be remembered that the maximum cooling efficiency is not possible with the ripener more than half full as was the case in these experiments. \^ The temperature of the cream and water in the morning is given to show to what extent the ripener is capable of holding temperature. The nights during these tests were 'moderately warm. With uniced water a low temperature is not possible. One warm day the ripener was run during the entire forenoon and the larger portion of the afternoon, and yet, after all this run, the temperature of the cream was still 56, and this in spite of the fact that the water was pumped directly from the well into the ripener. In no case was a temperature lower than this obtained with 80 CREAMERY BUTTER MAKING the uniced water, which had a temperature of 51 to 52 as it entered the ripener. When we compare the quick coolhfg with iced water and the slow and inadequate cooling with uniced water, it is easily seen that the saving in fuel and wear and tear of machinery will more than cover the cost of the ice. Moreover, quick cooling has a very important ad- vantage in cream ripening. It permits the use of a large amount of starter which is not possible where good cool- ing facilities are not at hand. Using iced water makes it possible to have cream with the same degree of acidity 365 days in the year, and it is believed that the general use of the improved cream ripeners with ice water attach- ments will result in a great improvement in both the quality and uniformity of butter and do away with the dangerous practice of adding ice directly to the cream. DANGER OF ADDING ICE TO CREAM. Adding ice to the cream is a pernicious practice, both because of its tendency to lower the quality of the butter and of the danger of infecting it with disease producing germs. This is so because most of the ice used is more or less contaminated with filth and various kinds of germs. Moreover,- a good bodied cream cannot be obtained where it becomes excessively diluted with ice water. Butter makers general!}/ realize these facts but are often forced into the practice of adding ice to the cream because proper cooling facilities are not available. One of the contestants in our Educational Butter Scoring Test writes as follows : "The ice we have been using comes from a mill pond, a very filthy hole. I did not use it in the cream until July when I was obliged to in order CREAMERY BUTTER MAKING 81 to get the cream cold enough. I am satisfied that is one reason my butter has such a poor flavor." Compare his scores for May and June when no ice was used in the cream, with those for July and August when ice was added. Score for May, 92^2; score for June, 94; score for July, 87 ; score for August, 88. PART III. ACID TESTS FOR MILK AND CRKAM. Butter makers who have had years of experience and who' rank high in the profession of butter making, do not find it safe to rely upon their noses in determining the ripeness of cream for churning. They use in daily prac- tice tests by which it is possible to determine the actual amount of acid present. The method of using these tests is based upon the simplest form of titration. Titration. This consists in neutralising an acid with an alkali in the presence of an indicator which determines when the point of neutrality has been reached. Acids and alkalies are substances that have entirely opposite chemical properties. The acid in milk gives it its sour taste, and for our purpose, illustrates very well what we mean by an acid. Ordinary lime may be used to illustrate what we mean by an alkali. When lime is added to sour milk the acid unites with the lime forming a neutral substance which is neither alkaline nor acid. If we keep on adding lime to the milk we reach a point at which all the acid has combined with the lime. This is called the point of neutrality. The moment this point is passed is made visible to the eye by means of the indicator (phenolphthalein) which is colorless in the presence of an acid but pink in the presence of an alkali. One drop of alkali added to milk after the acid has been neutralized will turn it pink. 82 CREAMERY BUTTER MAKING In the tests used for milk and cream the alkali used is sodium hydroxide. This' is made up of a definite strength so that the amount of acid can be calculated from the amount of alkali used. Kinds of Tests. There are two tests in general n sc- at the present time : one devised by Prof. Manns and known as the Manns' Test ; the other devised by Prof. Farrington and known as Far- rington's Alkaline Tablet Test. MANNS' TEST. The apparatus used in this test is illustrated in Fig. 28. It consists of a 50 c.c. burrette, a 50 c.c. pipette, a small fun- nel, and a glass beaker with stirring rod. The alkali (not shown in the figure) can be bought ready made in gallon bottles and is labeled "neutral- izer." This alkali or neutral- izer is made by dissolving four grams of sodium hydroxide in enough water to make one liter solution. The solution thus formed is called a one-tenth normal solution, each cubic centimeter of which contains .004 of a gram of sodium hydroxide which will neutralize .009 of a gram of lactic acid. Making the Test. Measure 50 c.c. of cream with the pipette into the beaker, then with the same pipette add 50 c.c. of water. Now add five or six drops of indicator. Next fill the burrette to the zero mark with the neutralizer Fig. 28. Manns' acid test appa- ratus. CREAMERY BUTTER MAKING 83 and slowly run this from the burrette into the cream, shaking the beaker after each addition of alkali. With the first few additions of alkali the pinkish color pro- duced quickly disappears. But when the point of neu- trality approaches, the color disappears, very slowly and the neutralizer must be added drop by drop only. The moment the cream remains pink indicates that the acid has all been neutralized. The number of cubic centimeters of alkali added to the cream is then noted, and from this the percentage of acid is calculated according to the following formula: No. c.c. alkali X .009 Per cent acid = No . c>c . cream -- X 100. Example : What is the percentage of acidity when 30 c.c. of .alkali are required to neutralize 50 c.c. of cream ? From the formula it is evident that any amount of cream may be used for a test. But more accurate results are obtained by using 50 c.c. than less. Where this amount of cream is always used the formula may be con- siderably simplified. Thus, by dividing the numerator and denominator by 50, the . / No. c.c. alkali X .009 \ expression I FH - X 100 1 becomes (No. c.c. alkali X .009 X 2) or (No. c.c. alkali X .018). The acidity in the problem above would therefore equal 30 X .018 = .54$. HARRINGTON'S ALKAUNE TABLET TEST. In the Farrington test the same alkali is used as in Manns', but in a dry tablet form in which it is more 84 CREAMERY BUTTER MAKING easily handled than in the liquid form. Each tablet con- tains enough alkali to neutralize .034 gram of lactic acid. Apparatus Used for the Test. This is shown in Fig. 29 and consists of a porcelain cup, one 17.6 c.c. pipette, and a 100 c.c. rubber-stoppered graduated glass cylinder. PJFETTE: Fig. 29. Farrington acid test apparatus. Making the Solution. The solution is made in the graduated cylinder by dissolving 5 tablets in enough water to make 97 c.c. solution. When the tablets are dis- solved, which .takes from six to twelve hours, the solution should be well shaken and is then ready for use. The solution of the tablets may be hastened by placing the graduate in a reclining position as shown in the cut. Making the Test. With the pipette add 17.6 c.c. of cream to the cup, then with the same pipette add an equal amount of water. Xow slowly add of the tablet solution, CREAMERY BUTTER MAKING 85 rotating the cup after each addition. As soon as a per- manent pink color appears, the graduate is read and the number of c.c. solution used will indicate the number of hundredths of one per cent of acid in the cream. Thus, if it required 50 c.c. of the tablet solution to neutralize the cream then the amount of acid would be .50%. From this it will be seen that with the Farrington test no calcu- lation of any kind is necessary. TESTING THE ACIDITY OF MIUC. The acidity of milk may be determined in the same way as that of cream, except that the milk need not be diluted with water before adding the alkali. A Rapid Acid Test for Milk. Where milk is pasteur- ized it is often desirable to determine approximately the acidity of each lot as it arrives at the creamery. It has been found that milk that contains more than .2% acid cannot be satisfactorily pasteurized. Farrington and Woll have devised the following rapid method for testing the acidity of milk that is to be pasteurized : Prepare a tablet solution by adding two tablets for each ounce of water. When the tablets have dissolved, take the solution into the intake. Now, as each lot is dumped into the weigh can a sample of milk is taken with a No. 10 brass cartridge shell and emptied into a teacup. With another, or the same, No. 10 shell add a measure of tablet solution to the cup. Mix the alkali and milk by giving the contents of the cup a rotary motion. If the milk remains white it contains more than .2% acid; if it is colored, there is less than .2% acid present. Where the tablet solution is prepared as above care must be taken to secure equal quantities of milk and solution for the test. 86 CREAMERY BUTTER MAKING PRECAUTIONS IN MAKING ACID TESTS. 1. Always thoroughly mix the cream or milk before taking a sample for a test. 2. Prepare the tablet solution and dilute the cream with water as nearly neutral as possible. Soft water is better than hard. 3. Keep the tablets dry and well bottled. 4. Keep the Manns neutralizer and the Farrington tablet solution carefully stoppered with a rubber stopper, as exposure to the air will weaken the solutions by absorb- ing carbonic acid. 5. With the Farrington tablets it is best to prepare a new solution every day. 6. Make the tests where there is plenty of light so that the first appearance of a permanent pink color can readily be noticed. RELATION OF RICHNESS AND ACIDITY IN CREAM. In practice we find that the ripening is slower in rich than in poor cream. The reason for this is that the acid develops in the milk serum, which really should be used as the basis in measuring the degree of acidity, if this were possible. In a cream testing 25% we find that more acid must be developed to get the desired effects in cream ripening than is necessary in a 35% cream. This is so because in the 25 % cream we have the acid distributed through 75% milk serum, while in the 35% cream it is distributed through only 65% milk serum. If both the above creams show an acidity of .5%, this means that in the poor cream the .5 pound of acid is distributed through 75 pounds of serum, while in the rich CREAMERY BUTTER MAKING 87 cream it is distributed through only 65 pounds of serum, hence the latter must have the greater intensity of acidity. This may be graphically shown as follows : Poor cream. Rich cream. 25% fat. 75 'j, serum, acid. 35$ fat. 65% serum. .5% acid. In the illustrations above it is seen that the acid in the rich cream is distributed through less space than in the poor, hence the degree of acidity must be higher in tb rich cream. We find in practice where the same results are to be expected from the ripening process, a 25% cream must show about .6% acidity, while a 35% cream, about .$%. In bulletin No. 24 of the Washington Experiment Sta- tion, Prof. Spillman gives a table showing the required acidity for cream of different richness. CHAPTER VIII. STARTERS. The value of carefully selected cultures of lactic acid producing bacteria in cream ripening was first demon- strated by Dr. S torch, of Copenhagen, a little less than a decade and a half ago. Since then the use of these cultures has spread so rapidly that few successful cream- eries can be found at the present time in which they are not used. Definition. Starter is the general term applied to cultures of lactic acid organisms, whether they have been selected artificially in a laboratory, or at creameries by picking out lots of milk that seem to contain these organ- isms' to the exclusion of others. A good starter may be defined as a clean flavored batch of sour milk or sour skim-milk. The word starter derives its name from the fact that a starter is used to "start" or assist the development of the lactic fermentation in cream ripening. Object of Starters. Cream ordinarily contains many kinds of bacteria good, bad, and indifferent and to insure the predominance of the lactic acid type in the ripening process it is necessary to reinforce the bacteria of this type already existing in the cream by adding large quantities of them in a pure form, that is, unmixed with undesirable species. The bacterial or plant life of cream may be aptly com- pared with the plant life of a garden. In both we find plants of a desirable and undesirable character. The 88 CRHAMHRY BUTTER MAKING 89 weeds of the garden correspond to the bad fermentations of cream. Jf the weeds get the start of the cultivated vegetables, the growth of the latter will be checked or suppressed. So with the bacterial fermentations of cream. When the lactic acid bacteria predominate, other fermentations will be checked or crowded out. The use of a liberal amount of starter nearly always insures a majority of good bacteria and the larger this majority the better the product. Classification of Starters. The following is a classi- fication of the various starters in use at the present time : Starters. f Natural f Sour skjm-milk ) Desirable. Undesirable. Sour milk .... } Sour cream ) Buttermilk ) O. Douglas Cultures < (Boston, Mass,). .. ( 1. Boston Butter Culture 2. Lactic Acid Culture. 3. Duplex Culture. Commer c i a 1 * (American) . . . H g&ss&'A-oj 1. Boston Butter Culture . Lactic Acid Culture. 3. Duplex Culture. Elov Erricson (Mankato, Minn.). j Hansen's Lactic Ferment (Little Falls, N. Y.). and a few others. NATURAL STARTERS. Sour Milk and Skim=milk. Natural starters are those obtained by allowing milk, skim-milk, or possibly cream, to sour in the ordinary way. The earlier methods of using natural starters consisted in selecting milk or skim-milk from the patrons who furnished the best milk at the creamery, and allowing this to sour by holding it over till the following day. While good milk could be selected in this way, the method of souring it was very unsatisfactory. On warm days the milk might oversour, while on cooler days it would be 90 CRHAMEfty BUTTER MAKING ' found comparatively sweet unless a good deal of atten- tion was given to keeping the temperature where it would sour in the proper length of time. This method of starter making is rapidly falling into disuse. The most satisfactory natural starters are selected and prepared in the following manner : Secure, say, one quart of milk from each of half a dozen healthy cows not far advanced in lactation, and fed on good feed. Before drawing the jnilk, brush the flanks and udders of the cows and then moisten them with water or, preferably, coat thinly with vasaline to prevent dislodgement of dust. Then, after rejecting the first few streams, draw the milk into sterilized -quart jars provided with narrow necks. Now allow the milk to sour, uncovered, in a clean, pure atmosphere at a temperature between 65 and 90 F. When loppered pour off the top and introduce the sample with the best flavor into fifty pounds of sterilized skim- milk and ripen at a temperature; at which it will sour in twenty- four hours (about 65 F.). A starter thus selected can be propagated for a month or more by daily inoculating newly sterilized or pasteur- ized milk with a small amount of the old or mother starter. Usually three or four pounds of the mother starter added to one hundred pounds of pasteurized skim-milk will sour it in twenty- four hours at a temperature of 65 F. Under certain conditions of weather this amount may possibly have to be modified a little, for it is well known that on hot sultry days milk will sour more quickly at a given temperature than on cooler days. The* best rule to follow is to use enough of the mother starter to sour the milk in twenty-four hours at a temperature of 65 F. Buttermilk and Sour Cream. If the cream has a good flavor, a portion of this, or the buttermilk from it, CREAMERY BUTTER MAKING 91 may be used as a starter. But in the case of unpasteurized cream, even though the flavor is good, there are always present some undesirable germs which will multiply in each successive batch of cream or buttermilk used as a starter, so that after a week's use the flavor may actually be bad. Where cream is slightly off flavored and a por- tion of this, or the buttermilk from it, is used as a starter, it will readily be seen that the taint will not only be transmitted but will multiply in the cream from day to day. The use of either cream or buttermilk as a starter is therefore never to be recommended. COMMERCIAL STARTERS. Commercial starters may consist of a single species of lactic acid organisms, but usually they are made up of a mixture of several species. These starters are pre- pared in laboratories where the utmost precautions are taken to keep them free from undesirable germs. The methods by which the good bacteria are separated from the bad are quite complicated and of too little practical value to permit a discussion of them here. Suffice it to say that such separation is possible only with the skilled bacteriologist. Keith and Douglas each manufacture three different cultures which are put upon the market in liquid form, the liquid usually being bouillon, or beef extract, treated with milk sugar. The development of the germs in this medium is very rapid and the cultures should therefore not be used later than ten days after they are sent out from the manufacturer unless they are kept at low tem- peratures. The reason for this is that the rapid growth of the bacteria will quickly result in vast numbers of them, 92 CRBAMBRY BUTTER MAKING which, together with their by-products, is fatal to their development. The chief difference in the three cultures prepared by these men lies in the intensity of acid produced. The "lactic" is the most vigorous, and the "Boston" the least vigorous acid producing culture, while the "duplex" seems to take an intermediate position. Sometimes, how- ever, it is difficult to distinguish between these cultures. Erricson's culture has only recently been placed upon the market but is already popular. It is sent out in the form of a liquid which appears to consist of sterilized milk to which some sugar has been added. Hansen's lactic ferment is put up in the form of a powder which consists chiefly of sterilized milk with possibly slight additions of casein and starch. In this dry powdery medium the germs remain in a dormant condition. When held a long time in this condition their vitality seems to become impaired. Preparation. Most of the commercial cultures are sent out in one ounce bottles which are hermetically sealed. The method of making starters from them is the same for all whether they are obtained in the liquid or in the dry form. In making the first batch of commercial starter, the entire contents of the bottle is put into a quart of skim- milk, sterilized by keeping it at a temperature of 200 F. for two hours, and then cooling to 80 which temperature should be maintained until the starter has thickened. A new starter is now prepared by introducing the quart of starter into fifty pounds of skim-milk, pasteurized by keeping it at a temperature of 170 to 185 for thirty minutes and then cooling to 65 F. All subsequent starters are prepared in the same way except that the amount of CREAMERY BUTTER MAKING 93 mother starter for inoculation must be reduced a little for a few days because the germs become more vigorous after they have propagated several days. In preparing the first starter from a bottle of culture it is necessary to have the skim-milk sterile. For if any spores should remain, the slow souring would give them a chance to develop which might spoil the starter. More- over, the cooked flavor imparted by the prolonged heating at high temperatures does not matter in the first starter as this should never be used to ripen cream. The first and second starters prepared from a new culture seldom have the good flavor produced in subsequent starters. The cause of this in all probability is the inactive condi- tion of the germs and the peculiar flavor of the medium in which they are sent out. In the starters prepared later the destruction of the spores is not so essential as the lactic acid germs are then in a vigorously growing condition which renders the spores practically harmless. At any rate the harm done by them would be less than that causecl ,by the sterilizing process. When milk is pasteurized at 170 to 185 F. for thirty minutes the vegetative germs are destroyed and but little cooked flavor is noticeable. NATURAL VERSUS COMMERCIAL STARTERS. Experimental tests have shown that equally good results can be secured with commerical and natural starters. It is believed, however, that the average butter maker can get the best results with commercial starters. Too few are good judges of milk and for this reason are not always capable of selecting the best for natural starters. Standard commercial cultures can be relied upon as giv- ing uniformly good results. 94 CREAMERY BUTTER MAKING From what has been said of the methods of preparing starters it must have been noticed that they are essentially the same for both the natural and the commercial, the chief difference being in the original ferment, which in the case of the natural starter consists of a quart of selected milk allowed to sour naturally, while in the com- mercial it consists of a bottle of culture prepared in a laboratory. USING A STARTER EVERY OTHER DAY. During the winter when milk is received every other day at creameries the ordinary method of preparing starters daily is, of course, out of question. There are two ways, -however, in which starters may be carried along during this time. One way is to keep the starter an extra twenty- four hours by holding it at a temperature below 50 after it has soured. The other and more satisfactory way is to prepare a small starter on the day the milk is separated ; and, in addition, to pasteurize, but not inoculate, the amount of skim-milk needed for the regular starter. This milk is repasteurized the following day and then inoculated from the small starter prepared the day previous. The object in repasteurizing the milk is to destroy the spores that have developed into the vegetative state. HOW TO SELECT MILK FOR STARTERS. It is poor practice to select starter milk promiscuously. The sweetest and best flavored milk should be obtained for the preparation of starters. Where possible the best plan is to select the morning's milk of one of the earliest patrons at the creamery and separate this first. In case CREAMERY BUTTER MAKING 95 the best milk is received toward the middle or close of the run, it should be carried into the creamery and separated by itself so as to secure the skim-milk without contamina- tion from other milk of inferior flavor. It must not be supposed that any milk may be made into a first-class starter by thorough pasteurization and inocu- lation with good cultures of bacteria. The best starters are possible only with the best milk. WHOLE: MIUC STARTERS. Where whole milk is used for making starters the cream should always be skimmed off before using the starter. Indeed it is good practice to skim off the top of any starter before using as the surface is liable to become contaminated from exposure to the air. ACIDITY OF STARTERS. It has already been stated that a starter is at its best immediately after it has thickened when it usually shows about .7% acid. It must not be supposed, however, that all starters are at their best when they show this amount of acid, because different starters thicken with different degrees of acidity. Nor must it be supposed that a starter that tends to sour very quickly is better than one that sours slowly. Marshall, of the Michigan Agricultural College, has recently found that when certain alkali pro- ducing bacteria are associated with the lactic acid organ- isms the milk sours more quickly than when the alkali bacteria are not present. These alkali producing bacteria, while they hasten the souring, produce an undesirable flavor. This probably explains why starters that have a tendency to sour very rapidly are often inferior to those 96 CREAMERY BUTTER MAKING that sour less rapidly. Usually, too, starters after they have been propagated for some time, become intensely acid producing, which is probably due to contamination with the peculiar alkali producing bacteria. RENEWAL OF STARTERS. Under average creamery conditions it is policy to renew the starter at least once a month by purchasing a new bottle of culture. It will be found that after the starter has been propagated for two or three weeks bad germs will begin to manifest themselves as a result of imperfect pasteurization, contamination from the air, or from over- ripening, so that its original good flavor may be seriously impaired at the end of one month's use. It is only where the utmost precautions are taken in pasteurizing the milk and ripening the starter, that it is possible to propagate a starter for many weeks and still maintain a good flavor. VALUE OF CARRYING SEVERAL STARTERS. There is always some possibility of losing a starter by overripening or by accidental contamination which would deprive the butter maker of the use of a starter for several days. To insure against this, butter makers should practice carrying a few extra ones in quart cans. This has the additional advantage of offering some choice. The best is, of course, always selected for regular use. The milk for the small starters should be sterilized rather than pasteurized. This practice of carrying several starters is strongly recommended. CREAMERY BUTTER MAKING 97 STARTER CANS. The most difficult thing in connection with starters is to get them just ripe when ready to use. A starter has its best flavor right after it has thickened. When it "begins PEN M SOLE tOPEKAl Fig. 30. Haugdahl starter can. to show whey it indicates that the ripening has gone too far and should not then be used in the cream. The strong and curdy flavors found in butter are often directly attrib- utable to overripened starters. It becomes evident that to secure the proper acidity in the starter from day to day cans or vats must be used in which it is possible to obtain perfect control of tempera- ture. The improved Haugdahl starter can, shown in Fig. 30, answers the purpose very satisfactorily. This can is 98 CRUAML'Ry BUTTUR MAKING portable and provided with a double jacket between which steam, hot water, cold water, or ice water may be circu- lated as the case may demand. It is also provided with an agitator which is operated by power. POINTERS ON STARTERS. 1. Starters give best results when added to cream immediately after they have thickened. 2. An overripe starter produces somewhat the same effect in butter as overripened cream. Curdy flavors are usually the result of such starters. 3. To prevent overripening, starter cans or starter vats must be used in which the temperature can be kept under perfect control. 4. Skim-milk furnishes the best medium for starters, since this has undergone the cleansing action of the sepa- rator and is free from fat, which hampers the growth of lactic acid bacteria. 5. Agitate and uncover the milk while heating to in- sure a uniform temperature and to permit undesirable odors to escape. 6. Always dip the thermometer in hot water before inserting it in pasteurized milk. The pasteurizing process becomes a delusion when dirty thermometers are used for observing temperatures. 7. Always use a sterilized can for making a new starter. 8. Keep the starter can loosely covered after the milk has been heated to prevent germs from the air getting into it. 9. Stir the starter occasionally the first five hours after inoculation to insure uniform ripening. MHRY BUTTER MAKING 99 10. Never disturb the starter after it has begun thick- ening until ready to use. 11. When a new bottle of commercial culture is used, the first two starters from it should not be used in cream as the flavor is usually inferior on account of the slow growth of the bacteria and the undesirable flavor imparted by the medium in which the cultures are sent out. A commercial starter is usually at its best after it has been propagated a week. 12. Always sterilize the neck of a new bottle of culture before emptying the contents into sterilized skim-milk. CHAPTER IX. CHURNING. Theory. Under the physical properties of butter fat it was mentioned that this fat existed in milk in the form of extremely minute globules, numbering about 100,000,- ooo per drop of milk. In rich cream this number is in- creased at least a dozen times owing to the concentration of the fat globules during the separation of the milk. So long as milk and cream remain undisturbed, the fat remains in this finely divided state without any tendency whatever to flow together. This tendency of the globules to remain separate was formerly ascribed to the supposed presence of a membrane around each globule. Later re- searches, however, have proven the falsity of this theory and we know now that this condition of the fat is due to the surface tension of the globules and to the dense layer of casein that surrounds them. Any disturbance great enough to cause the globules to break through this caseous layer and overcome their sur- face tension will cause them to unite or coalesce, a process which we call churning. In the churning of cream this process of coalescing continues until the fat globules have united into masses visible in the churn as butter "granules. CONDITIONS THAT INFLUENCE CHURNING. There are a number of conditions that have an impor- tant bearing upon the process of churning. These may be enumerated as follows: 100 CREAMERY BUTTER MAKING 101 1. Temperature. 2. Character of butter fat. 3. Acidity of cream. 4. Richness of cream. 5. Amount of cream in churn. 6. Speed of churn. 7. Abnormal fermentations. 1. Temperature. To have the microscopic globules unite in churning they must have a certain degree of soft- ness or fluidity which is greater the higher the tempera- ture. Hence the higher the temperature, within certain limits, the quicker the churning. To secure the best results the temperature must be such as to churn the cream in from thirty to forty-five minutes. This is brought about in different creams at quite different temperatures. The temperature at which cream must be churned is determined primarily by the character of the butter fat and partly also by the acidity and richness of the cream. Rule for Churning Temperature. A good rule to fol- low with regard to temperature is this : When the cream enters the churn- with a richness of 30 to 35 per cent and an acidity of .5 to .6 per cent, the temperature should be such that the cream will churn in from thirty to forty- five minutes. This will insure an exhaustive churning and leave the butter in a condition in which it can be handled without injuring its texture. Moreover, the but- termilk can then be easily removed so that when a plug is taken with a trier the day after it is churned the brine on it will be perfectly clear. 2. Character of Butter Fat. The fat globules in cream from different sources and at different times have the proper fluidity to unite at quite different temperatures. 102 CREAMERY BUTTER MAKING This is so because of the differences in the relative amount of "soft" and "hard" fats of which butter fat is composed. When the hard fats largely predominate the butter fat will of course have a high melting point. Such fat may be quite hard at a temperature of 60 while a butter fat of a low melting point would be comparatively soft at this temperature. For a study of the conditions that influence the hardness of butter fat the reader is referred to the discussion of the "insoluble fats" treated in the chapter on milk. 3. Acidity of Cream. This has a marked influence on the churning process. Sour or ripened cream churns with much greater ease than sweet cream because the acid renders it less viscous. The ease with which the fat globules travel in cream becomes greater the less the viscosity. Ripe cream will therefore always churn more quickly than sweet cream. Ripe cream also permits of a higher churning temperature than sweet which is of great practical importance where it is difficult to secure low churning temperatures. 4. Richness of Cream. It may naturally be inferred that the closer the fat globules are together the more quickly they will unite with the same amount of concus- sion. In rich cream the globules are very close together which renders it more easily churnable than thin cream. The former can therefore be churned in the same length of time at a lower temperature than the latter. The ideal richness lies between 30% and 35%. A cream much richer than this will stick to the sides of the churn which reduces the amount of concussion. The addi- tion of water to the churn will overcome this stickiness and cause the butter to come in a reasonable length of .CREAMERY BUTTER MAKING 103 time. It is better, however, to avoid an excessive richness when an exhaustive churning is.to be expected. 5. Amount of Cream in Churn. 'The best and quick- est churning is secured when the churn is one-third full. With more or less cream than this the amount of concus- sion is reduced and the length of time in churning cor- respondingly increased. 6. Speed of Churn. The speed of the churn should be such as to produce the greatest possible agitation or concussion of the cream. Too high or too low a speed reduces the amount of concussion. The proper speed for each particular churn must be determined by experiment. 7. Abnormal Fermentations. The slimy or ropy fer- mentation sometimes causes trouble in churning by ren- dering tjle cream excessively viscous. Cream from single herds may become so viscous as to render churning im- possible. At creameries where milk is received from many herds very little trouble is experienced from these fer- mentations. CHURNS. A churn is a machine in which the cream is made to slide or drop, or is in some way agitated to bring about the union of the fat globules, which changes the liquid fat into a solid. For many years the factory churns had assumed the form of a box or barrel free from any inside fixtures. Such churns were revolved by power and did very satisfactory work. But it was necessary to transfer the butter, after it was churned, to a worker upon which it was worked. This transfer from one piece of apparatus to another was obviated by the invention of "combined" churns and 104 CREAMERY BUTTER MAKING workers (Figs. 31 and 32) placed upon the market a little more than a decade ago. These are provided with rollers inside, which remain stationary during churning, but can be made to revolve when it is desired to work the butter. CREAMERY BUTTER MAKING 105 The combined churns have to a great extent replaced the old box and barrel styles because of the many advan- tages they possess over the latter. The principal advan- tages may be stated as follows : Fig. 32. Dlsbrow combined churn and butter worker. 1. They occupy less space. 2. Require less belting and fewer pulleys. 3. The churn can be kept closed while working which keeps the warm air and flies out during the summer. 4. The butter can be made with considerably less labor. A few disadvantages might be mentioned such as the greater original cost and the greater difficulty of cleaning and salting. But with proper care the butter may be evenly salted and the churns kept clean. CHURNING OPERATIONS. Preparing the Churn. Before adding the cream, the churn should be scalded with hot water and then thoroughly rinsed with cold water. This will "freshen" 106 CRtiAMtiRY BUTTl-.R- MAKING the churn and fill the pores of the wood with water so that the cream and butter will not stick. Straining Cream. All cream should be carefully strained into the churn. This removes the possibility of white specks in butter which usually consist of curd or dried particles of cream. Adding the Color. The amount of color to be added depends upon the kind of cream, the season of the year, and the market demands. Jersey or Guernsey cream requires much less color than Holstein because it contains more natural color. During the summer when the cows are feeding on pastures the amount of color needed may be less than half that required in the winter when the cows are feed- ing on dry feed. Different markets demand different shades of color. The butter must therefore be colored to suit the market to which it is shipped. In the winter time about one ounce of color is required per one hundred pounds of butter. During the summer less than one-half ounce is usually sufficient. In case the color is not added to the cream (through an oversight) it may be added to the butter at the time of working by thoroughly mixing it with the salt. When the colored salt has been evenly distributed through the butter the color will also be uniform throughout. Kinds of Color. There are two classes of butter color found upon the market. One is a vegetable color having its origin in the annatta and other plants, the other is a mineral color, a product of coal tar. Both are entirely satisfactory so far as they impart to butter a desirable color. But from a sanitary standpoint the vegetable color CREAMERY BUTTER MAKIXG 107 seems to be preferred though the odor due to the vege- table oils has been objected to by butter experts. Gas in Churn. During the first five minutes of churn- ing the vent of the churn should be opened occasionally to relieve the pressure developed inside. This pressure according to Babcock k 'is chiefiy due to the air within becoming saturated with moisture and not to gas set free from the cream." Size of Granules. Butter should be churned until the granules are about half the size of a pea. When larger than this it is more difficult to remove the buttermilk and distribute the salt. When smaller, some of the fine grains are liable to pass out with the buttermilk, and the per- centage of water in the butter is reduced. When the granules have reached the right size, cold water should be added to the churn to cause the butter to float. Salt will answer the same purpose. The churn is now given two or three revolutions and the buttermilk drawn off. Washing Butter. One washing in which as much water is used as there was cream is usually sufficient. When butter churns very soft two washings may be advantageous. Too much washing is dangerous, how- ever, as it removes the delicate flavor of the butter. Too much emphasis cannot be laid upon the importance of using clean, pure water for washing. Experiments conducted at the Iowa station and elsewhere have shown that impure water seriously affects the flavor of butter. When the water is not perfectly pure it should be filtered or pasteurized. SALTING. It is needless to say that nothing but the best grades of salt should be used in butter. This means salt readily 108 CREAMERY BUTTER MAKING soluble in water and free from impurities. If there is much foreign matter in salt, it will leave a turbid appear- ance and a slight sediment when dissolved in a tumbler of clear water. Rate of Salt. The rate at which butter should be salted, other conditions the same, is dependent upon market demands. Some markets like Boston require much salt in butter while some buyers in the New York market require scarcely any. The butter maker must cater to the markets with regard to the amount of salt to use as he does with regard to color. The rate of salt used does not necessarily determine the amount contained in butter. For instance it is per- fectly possible under certain conditions to get a higher percentage of salt in butter by salting at the rate of one ounce per pound than is possible under other conditions by salting at the rate of one and a half ounces. This means that under some conditions of salting more salt is lost than under others. The amount of salt retained in butter is dependent upon : 1. Amount of drainage before salting. 2. Fineness of butter granules. 3. Amount of butter in churn. 1. When the butter is salted before the wash water has had time to drain away, any extra amount of water remaining will wash out an extra amount of salt. It is good practice, however, to use a little extra salt and drain less before adding it as the salt will dissolve better under these conditions. 2. Small butter granules require more salt than large ones. The reason for this may be stated as follows : The surface of every butter granule is covered with a thin CREAMERY BUTTER MAKING 109 film of water, and since the total surface of a pound of small granules is greater than that of a pound of larger ones, the amount of water retained on them is greater. Small granules have therefore the same effect as insuffi- cient drainage, namely, washing out more salt. 3. Relatively less salt will stick to the churn in large churnings than in small, consequently less will be lost. Standard Rate. The average amount of salt used in butter made in the combined churns comes close to one and a half ounces per pound of butter. But the rate de- manded by different commission men may vary from no salt to two and a half ounces per pound of butter. With the combined churns great care must be exercised to get the salt evenly distributed from one end of the churn to the other as it can not redistribute itself in the working. Brine Salting. This consists in dissolving the salt in water and adding it to' the butter in the form of a brine. This will usually insure an even distribution with less working since the salt is already dissolved. Where butter containing a high percentage of salt is demanded the method of brine salting is not practical, because it limits the amount that can be incorporated in butter. Where there is difficulty in securing an even distribu- tion of the salt without excessive working, an oversatu- rated brine may be used to advantage. Salt added to butter in this form very quickly dissolves and a butter with any degree, af salt is possible. But it is believed that where butter is drained little and a somewhat higher rate of salt is used, dry salting will never require overworking and will insure greater uni- formity than is possible with brine salting. Object of Salting. Salt adds flavor to butter and 110 CREAMERY BUTTER MAKING materially increases its keeping quality. Very high salt- ing, however, has a tendency to detract from the fine delicate aroma of butter while at the same time it tends to cover up slight defects in the flavor. As a rule a butter maker will find it to his advantage to be able to salt his butter rather high. Salt an Absorbent. Salt very readily absorbs odors and must therefore be kept in clean, dry places where the air is pure. Too frequently it is stored in musty, damp store rooms where it will not only lump, but become impregnated with bad odors which seriously impair the quality of the butter. WORKING BUTTER. The chief object in working butter is to evenly incor- porate the salt. To accomplish this end with the least amount of working it is necessary to work butter twice. After the wash water has sufficiently drained away, the salt is carefully distributed over the butter and the churn revolved a few times with the rollers stationary. This will aid in mixing the salt and butter. The rollers are now set in gear and the butter worked about two minutes to fairly incorporate the salt. After this it is allowed to stand not less than half an hour to allow the salt to dis- solve when the working may be finished. How Much to Work. Butter is worked enough when the salt has been evenly distributed. Just when this point has been reached can not always be told from the appear- ance of the butter immediately after working. But after four or six hours standing the appearance of white streaks or mottles indicates that the butter has not been sufficiently worked. The rule to follow is to work the butter just enough to prevent the appearance of mottles CREAMERY BUTTER MAKING 111 after standing about six hours. Just how much working this requires every butter maker must determine for him- self, by experiment, for the reason that there are a number of conditions that influence the length of time that butter needs to be worked in a combined churn. These condi- tions are : 1. Amount of butter in the churn. 2. Temperature of the butter. 3. Time between workings. 4. Size of granules. 5. Solubility of salt. 1. When there is a moderately large amount of butter in the churn the working can be accomplished with fewer revolutions than with a small amount. Satisfactory work- ing can not be secured, however, when the capacity of the churn is overtaxed. 2. Hard, cold butter is difficult to work because the particles will not knead together properly. 3. A moderately long time between workings allows the salt to dissolve and diffuse through the butter and hence reduces the amount of working. 4. Coarse or overchurned butter needs a great deal of working because of the greater difficulty of distribu- ting the salt. 5. A salt that does not readily dissolve requires exces- sive working and is therefore productive of overworked butter. With such salt the brine method of salting is undoubtedly preferable. 112 CREAMERY BUTTER MAKING DIFFICULT CHURNING. The causes of trouble in churning may be enumerated as follows: (i) thin cream, (2) low temperature, (3) sweet cream, (4) high viscosity of cream, (5) churn too full, (6) too high or too low speed of churn, (7) colos- trum milk, (8) advanced period of lactation, and (9) ab- normally rich cream. Foaming. This is usually due to churning a thin cream at too low a temperature, or to a high viscosity of the cream. When caused by these conditions foaming can usually be overcome "by adding warm water to the churn. Foaming may also be caused by having the churn too full, in which case the cream should be divided and two churnings made instead of one. CLEANING CHURNS. After the butter has been removed, the churn should be washed, first with moderately hot w r ater, next with boiling hot water containing a little alkali, and finally with hot water. If the final rinsing is done with cold water the churn dries too slowly, which is apt to give it a musty smell. This daily washing should be supplemented once a week with a washing with lime water, which is prepared as follows: Gradually slake half a bushel of freshly burned lime by adding water to it at short intervals until about 150 pounds of water has been added. Stir the mixture once every half hour for several hours, after which allow it to remain undisturbed for about ten hours. " This permits the undissolved material to settle. The clear liquid is now poured off and added to the churn, which is CREAMERY BUTTER MAKING 113 slowly revolved for at least half an hour so that the lime water may thoroughly penetrate the pores of the wood. Nothing is equal to the cleansing action of well pre- pared lime water and its frequent use will prevent the peculiar churn odor that is bound to develop in churns not so treated. The outside of the churn should be thoroughly cleaned with moderately hot water containing a small amount of alkali. CHAPTER X. PACKING AND MARKETING BUTTER. Butter is usually in the best condition for packing immediately after the second working. It can then be packed solidly into the packages without the vigorous ramming necessary when the butter becomes too cold. When allowed to stand in the churn some time after work- ing during the warm summer days, the butter will usually get too soft for satisfactory packing. There is a great variety of packages in which butter may be packed for the markets. These may be con- veniently divided into two groups: (i) those used for home trade, and (2) those designed for export trade. Home Trade Packages. The bulk of the butter for home trade is packed in ash and spruce tubs, the former holding 20, 30, and 60 pounds, while the latter are made in 10, 20, 30, and 50 pound sizes. Before adding the butter, the tubs must be thoroughly scrubbed inside and outside, the hoops carefully set, and then soaked in hot water for about half an hour. After this they are steamed for three minutes and then allowed to soak in cold water not less than four hours. The sides and bottom of the tubs are next lined with parchment paper which has been soaked in strong brine for twenty- four hours. The wet liners are easily placed in the tubs by allowing them to project an inch and turning this over the edge. The tubs are now weighed and the butter packed into 114 CRBAMHRY BUTTER MAKING 115 them directly from the churn, adding about five pounds at a time and firmly packing it with a wooden packer made for this purpose. The butter should be packed solid so that when stripped of its package on the retailer's counter no open spaces will appear in it. When ash tubs are used they are packed brim full and trimmed off level with the tub by running a string across the top. The tubs are then weighed and the weights marked on the outside, allowing not less than half a pound for shrinkage for a sixty pound tub. A cheese cloth circle is next placed over the top and an oversatu- rated brine is pasted upon this. After careful cleaning place the covers on the tubs and fasten them with not less than three butter tub fasteners. With spruce tubs the method of packing is the same with the exception that most markets require an even number of pounds in a tub, as 30 or 50 pounds. The "tubs are, therefore, trimmed down till the required weight, plus half a pound for shrinkage, is reached. Some markets do not require the spruce tubs to be lined but it is always better to do so. Prints. Considerable quantities of butter made in creameries are put up in one pound oblong blocks called prints. Where many of these prints are made a printer like that shown in Fig. 33 is most serviceable. This makes twenty-five prints at a time. The prints are carefully wrapped in parchment paper which has been soaked in strong brine for twenty-four hours, and then packed in cheap wood boxes which usually hold about fifty of them. These boxes should be held not less than one day in a refrigerator before they are shipped. Print butter is growing in popularity. There are various other packages in which butter is 116 CREAMERY BUTTER MAKING packed, such as five pound crocks, gem fibre paper boxes lined with parchment and holding 2, 3, 4, 5, and 10 pounds, and the wooden bail boxes holding from 5 to 10 pounds. Most of these packages are used for local trade. Fig. 33. Butter printer. Foreign Trade Packages. For export trade butter is preferably packed in cubical spruce boxes lined with paraffin and holding 56 pounds. These boxes are pre- pared by rinsing them with cold brine and then lining with double thickness of parchment paper which has been soaked in strong brine. The boxes are now weighed and carefully packed, after which they are trimmed down to a weight of 57 pounds, which allows one pound for shrinkage. Finish the packing by placing a double thick- CREAMERY BUTTER MAKING 117 ness of parchment paper over the top and upon this over- saturated brine. Butter shipped to tropical countries is packed in tin cans which are hermetically sealed. MARKETING BUTTER. The producer of any commodity is always confronted with the problem of finding the best markets for his product. Indeed his success is measured more or less by his ability in handling this end of the business. Butter makers lose thousands and thousands of dollars every year because they do not fully understand how to manage the sale of their product. They fall into the clutches of men without credit or credentials who offer big prices but no returns. Swindlers are always on the lookout for victims and every year many butter makers are entrapped by them. To the one who is just beginning to seek a market for his butter the following course of procedure is recommended. 1. Find the names of three or more leading reputable butter firms in the leading butter markets by inquiring of men from whom trustworthy information may be ex- pected. 2. Divide a day's standard make among these butter firms and instruct each to send you statement as to the price they can give you net (f. o. b.) at your station for regular shipments, the price to be based on quotations of some leading market. Inform them further that you are ready and willing to comply with their demands as to color, package, and salt, in future shipments. 3. Ship your butter to the firm that offers you the best price, but do not deal with this firm exclusively. A tub 118 CREAMERY BUTTER MAKING should occasionally be sent to a new and reliable firm with a view to securing better prices. 4. Remember, however, that it requires time to estab- lish a good trade for butter. Frequent changes from one firm to another are therefore undesirable. 5. Do not sell butter on commission, but ask for prices f. o. b. your station, based on some market quotation like New York. 6. Demand that payment shall be made for each ship- ment of butter within two weeks after it is sent out. 7. Never send a firm a third shipment until the first has been paid for. 8. Butter that is not up to the standard should be marked and the firm properly instructed regarding its disposition. An attempt to crowd in an inferior ship- ment may cost you your regular, trade. 9. Do not feel hurt when criticisms come regarding defects in your butter but seek to overcome them. 10. Always allow one-half pound of butter for shrink- age on fifty and sixty pound tubs. If this allowance proves inadequate it indicates that the tubs have not been properly soaked or that the "house" is cutting you on weights. 11. Never contract butter for more than a year at a time. CHAPTER XI. CALCULATING DIVIDENDS. I. Whole Milk. It is customary to pay for milk at creameries once a month. Such payment is called the monthly dividend. The method by which this dividend is calculated depends, of course, on the basis upon which the milk is bought. Fortunately the large majority of creameries now pay for it according to the butter fat con- tent. Milk so paid for is spoken of as being bought by the "Babcock test" or on the "fat basis." Since it makes butter in proportion to the amount of fat it contains, the Babcock test or fat basis is manifestly the only just way of buying milk at creameries. This method will be dis- cussed in detail. CALCULATING DIVIDENDS ON A FAT BASIS. The different steps in this calculation are indicated as follows : 1. Find the total pounds of milk delivered by each patron for the month. 2. Find each patron's average percentage of butter fat for the month by averaging up the number of tests. 3. Multiply each patron's total milk for the month by the average percentage of butter fat it contains, the prod- uct will be the total pounds of butter fat delivered. 4. Add together all butter fat delivered by the patrons for the month, the sum will be the total butter fat. 5. Determine the total gross receipts for the month by multiplying each sale of butter by the price received 119 120 CREAMERY BUTTER MAKING per pound ; the sum obtained by adding all the sales will be the total gross receipts. 6. Calculate the amount charged to cover running ex- penses by multiplying the total pounds of butter by the price charged for making. 7. Subtract the sum charged to cover running ex- penses from the total gross receipts, the difference will be the net money due patrons. 8. The total net money divided by the total pounds of butter fat will give the average price per pound of butter fat. 9. Each patron's share of the monthly dividend is now found by multiplying his total butter fat by the average price per pound of butter fat obtained in 8. To make the above steps perfectly clear let us calculate a monthly dividend at a creamery in which A, B, and C are the patrons. Milk Pounds. Date. ABC I. August i 260 150 312 August 2 255 151 300 August 3 261 145 305 August 31 240 162 301 Total 8,091 4,650 9,405 Per cent of butter fat. Date. ABC August 7 3.3 4.2 3.6 August 15 3.4 4.3 3.6 August 23 3.4 4.2 3.7 August 31 3-3 4-0 3-6 4! 13.4 4| i6-7 4| 14-5 Average test .... 3 . 35 4 *7 3 62 CREAMERY BUTTER MAKING 121 A B C 4. Total milk. Ave. test. Total bu tier fat. 8,091 X ., V 271 . o=; Ibs. 4,6^0 X 4 17 193. ^j 91 Ibs. "H^O^ Q.4XX X 7. 62 340. 46 Ibs. Total :?)'-r^3 butter fat at Creamery = 805. 42 Ibs. Sales of butter. 205 Ibs . at 23 cts. = $47.15 240 Ibs . at 23 5 cts. = 56. 40 214 Ibs . at 24 cts. = 51 .36 269 Ibs . at 24 cts. = 64 .56 Total. . . 928 Total $219.47 6. Total pounds of butter = 928. Price charged for making = 3 cts. per pound. 928 X .03 $27.84 = Amount charged to cover running expenses. 7. $219.47 $27.84 = $191. 63 = Net money due patrons. 8. $191. 63 -^-805.42 = $.2379 = Average price per pound but- ter fat. 9. 271.05 X $.2379 = $64.48 = A's money. 193.91 X .2379= 46.i3 = B'smoney. 340.46 X .2379 = 81.00 = C's money. OVERRUN. In a well conducted creamery the total pounds of butter is always greater than the total pounds of butter fat. The excess is called the "overrun." In the above problem 805.42 pounds of butter fat made 928 pounds of butter. 928.00 805.42 = 122.58 = No. pounds overrun. 122.58-7- 805.42= 15.2 = Per cent overrun. 122 CREAMERY BUTTER MAKING MONTHLY STATEMENT. When the monthly payments are made each patron is presented with an envelope upon which is printed his indi- vidual account with the creamery and also the entire transactions of the creamery. A check on the nearest bank, or the money, is placed in the envelope and handed to the patron on "pay day." Below is shown such a monthly statement: CREAMERY BUTTER MAKING 123 Creamery Co. IN ACCOUNT WITH Mr For the month of 100 Cr. No. Ibs milk delivered Lbs butter. . Dr. @, by you - - - Cans @.. Average test, - Cash, No Ibs of butter f at Hauling @ Price per Ib " " per 100 Ibs $ $.. Balance due you, Total Ibs. milk delivered at creamery, Average test at creamery, Total Ibs. of Butter fat at creamery, Ibs. @_ $_ Sales of Butter. Less cts. for making. Balance due patrons, - = $ . Per cent, overrun . = = Testing witnessed by Prest. _Sec'y. 124 CREAMERY BUTTER MAKING The preceding pages show the correct method of calcu- lating the dividend at creameries. The author has learned from experience, however, that it is often difficult to make clear to patrons how the price per pound of butter fat is obtained. Frequently also competing creameries are in- clined to cut a little on the test to increase the price per pound of butter fat. Where trouble from these sources is experienced dividends may be apportioned on the plan indicated on the following monthly statement: CREAMERY BUTTER MAKING 125 Creamery Co. IN ACCOUNT WITH Mr.. for the month of. Balance due you, Total Ibs. milk delivered at creamery, Average test at creamery, Total Ibs. of Butter fat at creamery, Ibs. @ Sales of Butter. I Average price, per Ib. butter cts. for making. Testing witnessed by 190_ Cr. No Ibs. milk delivered by you, - - Dr. Average test, - s ' u er No Ibs. of butter fat, Cans, @, Overrun < Cash, - - - (Ibs Total Ibs. of butter Price per Ib " per 100 bs., $ 9 -. Prest. Sec'y. 126 CREAMERY BUTTER MAKING In this method the net price per pound of butter is used instead of the price per pound of butter fat. The method involves a little more work as each patron's over- run in pounds must be calculated separately. For clear- ness, however, we believe no other method surpasses this. The price of butter net to the patrons is obtained by subtracting the price charged for making from the aver- age price for which the butter has sold. This average price is found by dividing the total gross receipts by the total pounds of butter at the creamery, thus : Sales of butter. 205 Ibs. at 23 cts. = $47-15 240 Ibs. at 23^2 cts. = 56.4 214 Ibs. at 24 cts. = 51.36 269 Ibs. at 24 cts. 64.56 Total.. 928 Total $219. 47 $219.47-^-928 = $.2365 = Average price for which butter was sold. $.2365 less three cents for making = $.2065 = price of butter net patrons. The butter fat plus overrun multiplied by the net price gives each patron's portion of the dividend.- II. Whole Milk and Cream. Where both whole milk and cream are received at the creamery, the calculation of dividends for cream patrons differs from that for whole milk patrons in one point ; namely, in increasing each cream patron's total butter fat by 2%. The reason for this is that the cream patrons are credited with the butter fat found in the cream, while the whole milk patrons are credited with all the butter fat found in the milk, which is aboiit 2% more than would be found in the cream from the same milk, 2% of the butter fat being lost in the skim-milk. To illustrate : lUNIVERSr V^LIFO^; CREAMERY BUTTER MAKING 127 A delivers 6,500 pounds of milk testing 4.0%. B delivers 600 pounds of cream testing 30%. A's total fat = 6,500 X .04 = 260 pounds. B's total fat = 600 X .30 = 180 pounds. To increase B's fat by 2%, we multiply 180 by 1.02 which equals 183.6. In making the dividend, therefore, A is paid for 260 pounds of butter fat and B for 183.6 pounds. THE TWO PER CENT HOW CALCULATED. In a well conducted creamery the average loss of fat in the skim-milk should not be more than .078%. Dividing this figure by the average percentage of fat in milk, 3.9, we get .02. So that in the separating process .02 pound of fat is lost in the skim-milk for every pound of fat present in the milk. From the above calculation it will be seen that the cream factor (2%) would necessarily vary with the efficiency of skimming and the average test of the milk. To deter- mine what this shall be for any particular creamery divide the average loss of fat in the skim-milk by the average test of the milk at the creamery. CHAPTER XII. THEORETICAL OVERRUN. For the purpose of instructing patrons with regard to the percentage of overrun the following calculation is sub- mitted which incidentally involves the calculation of the amount of skim-milk and buttermilk to be returned from 100 pounds of milk, a calculation with which every but- ter maker should be familiar. i. To calculate the amount of skim-milk per 100 pounds of milk. Rule: Divide the per cent of fat in milk by the per cent of fat in cream and multiply the result by 100; the product subtracted from 100 will be the number pounds of skim-milk. Example : How much skim-milk is obtained from 100 pounds of 4% milk when the separator delivers a 40% cream ? 4 -*- 40 = .10, .10 X IOQ =10, 100 10 = 90 = No. Ibs. skim-milk. COROLLARIES, (i) The richer the milk and the poorer the cream the less skim-milk. (2.) The poorer the milk and the richer the cream the more skim-milk. To allow for variations in richness of cream and small overweights at the creamery, 3 should be subtracted from the calculated amount of skim-milk. Thus in the problem above, the skim-milk should be distributed on the basis of 87 instead of 90 pounds per 100 pounds of milk as calculated. 128 CRBAMBRY BUTTER MAKING 129 2. To calculate the amount of buttermilk per 100 pounds of milk. Rule : This is approximately found by increasing the pounds of butter fat in the cream by one-sixth and sub- tracting the result from the total pounds of cream. Example: How much buttermilk from 100 pounds of 4% milk yielding 10 pounds of cream testing 40% ? 10 X .40 = 4.0^ Ibs. of butter fat. 4X11/6 4.66, 10 4.66 = 5.34= No. Ibs. buttermilk. OVERRUN. The method of calculating the actual o.ver- run at creameries has already been discussed in Chapter XL With the following known conditions the theoretical overrun can be calculated with a fair degree of accuracy : ( T ) Average per cent of fat in butter. (2) Loss of fat in skim-milk. (3) Loss of fat in buttermilk. Problem : 100 pounds of milk testing 4% yields cream testing 40%. Test of skim-milk is '.05%, that of butter- milk .15%. Per cent of fat in butter is 84. Calculate butter and overrun. By applying the rules for calculating skim-milk and buttermilk we find that there will be 90 pounds of skim- milk and 5.34 pounds buttermilk. .90 X .05 = .045 = lb . fat in skim-milk. 534 X .15 = . 008= Ib. fat in buttermilk. Total loss = .053 4 .053 = 3,947 fat made into butter. 3.947 -f- .84= 4.70 = Ibs. butter made. 4.70 4= .70 = overrun in Ibs. .7~^4X 100=17.5 overrun in per cent. CHAPTER XIII. DISTRIBUTION OF SKIM-MILK AND BUTTERMILK. In recent years much attention has been given to the problem of skim-milk distribution at creameries. The old way of weighing on a common pair of scales is too slow and tedious. Efforts to improve upon this method of weighing have resulted in bringing upon the market vari- ous kinds of automatic weighing and measuring devices such as our skim-milk weighers and check pumps. With the skim-milk weigher the patron drops into the machine a check corresponding to the amount of milk delivered, and the amount of skim-milk called for by the check is weighed or measured out automatically. In the case of the check pump the operation is somewhat different. A check is dropped into the pump and, instead of flowing out, the amount of skim-milk called for by the check is pumped out. Some of these skim-milk weighers are giving good satis- faction when properly handled. But at least fifty per cent of the creameries are still adhering to the old methods of weighing on a common platform scales which, though tedious, is still perhaps the most accurate method. Attention is here called to an automatic valve closing arrangement, shown in. Fig. 34, which reduces the labor of weighing on a platform scales at least fifty per cent. A is a common pair of scales, B an ordinary receiving can with a two inch valve instead of a faucet, and C a device which closes the inlet valve, D, when the proper amount of skirn-milk has run into the can. It will be seen that one end of the rod, C, is attached to 130 CREAMERY BUTTER MAKING 131 the beam rod of the scales, while upon the other rests the handle which opens and closes the skim-milk valve. When the beam rises the connection is broken and the weight of the handle closes the valve. This makes it an auto- matic valve. Without this device the closing of the valve at the right time requires a good deal of watching which consumes too much time. A skim-milk table like that shown below should be posted in a conspicuous place so that no time needs to be wasted in calculating each patron's skim-milk. SKIM-MILK TABLE-85 POUNDS PER 100 POUNDS MILK. Milk. a| sa CO Milk. i! & Milk. 1! CO Milk. 1! CO 10 8 110 93 210 178 310 263 20 17 120 102 220 187 320 272 30 25 130 110 230 195 330 280' 40 34 140 119 240 204 340 289 50 42 150 127 250 212 350 360 297 60 51 160 136 260 221 306 70 59 170 144 270 229 370 314 80 68 180 153 280 238 380 323 90 76 190 161 290 246 390 331 100 85 200 170 300 255 400 340 132 CREAMERY BUTTER MAKING With the automatic valve it is possible for the man who weighs in the milk also to weigh out the skim-milk with little additional work. The device is unpatented and costs not more than one dollar. Attached to an ordinary plat- Fig. 34. Apparatus for distributing skim-milk and buttermilk. form scales, it furnishes with them an ideal skim-milk- weigher which is cheap, simple, accurate, and needs no repairs. BUTTERMILK DISTRIBUTION. To insure a just distribution of buttermilk at creameries it is necessary to either weigh or measure it out to the patrons. The long cylindrical can, X, shown at the left CREAMERY BUTTER MJKIX-G 133 in Fig-. 34, illustrates a very convenient and satisfactory measuring device. The measuring is done by means of a long hollow shaft, N, which consists of two boards be- tween which a pointer, M, is made to slide. Attached to the pointer is a string which passes over pulleys, O and P, and ends in the buttermilk can where it is attached to a wooden disc floating on top of the buttermilk. As the buttermilk flows into the can the disc rises, causing the pointer to sink in the shaft. Marks on the shaft indi- cate the number of pailfuls measured out. CHAPTER XIV. BUTTER JUDGING. Expert butter judges, like great musicians, are "born" not "made." A good musician must be born with a good ear, a good butter judge with a good nose. Most people, however, can become fair musicians with proper training, and the same may be said of butter judges. By repeated judging and comparing of different sam- ples of butter one will soon become able to make fair discriminations. The important point to learn. is to know an ideal butter when you see it. A butter maker can not expect to reach or even approach an ideal butter un- less he has the ideal fixed in mind. One can learn much about butter judging by daily ex- amining his own make. But to become expert, he must be able to compare his score with that of recognized experts. Dairy conventions and butter scoring tests offer excellent opportunities for such comparison. BASIS FOR JUDGING. Butter is judged commercially on the basis of 45 points for flavor, 25 for texture, 15 for color, 10 for salt, and 5 for package, total 100. Flavor. Strictly speaking flavor means taste. But the use of the term flavor in butter judging usually in- cludes both taste and aroma, the emphasis resting on the latter. Aroma is' the odor noticeable when a sample of butter is held close to the nose, hence frequently called "nose" aroma. 134 CRL'AMERV BUTTER MAKING 135 It is difficult to describe an ideal butter flavor. It may, perhaps, be likened to the flavor of clean, uncontaminated, well ripened cream, that is, it should be rich and creamy. Texture. This includes three distinct things : ( i ) grain, (2) body, and (3) brine. An ideal grain is indicated by a somewhat granular appearance when a piece of butter is broken, an appear- ance quite similar to that of the broken ends of a steel rod. Body refers to the consistency of butter. In other words, it refers to its degree of firmness or its ability to "set up" well at ordinary temperatures. Krine refers to the amount and character of the water in butter. It should be as clear as water and not present in such quantities as to run off the trier. Color. The essential thing in color is to have it uniform. It should have a little deeper shade than that produced by June pasturage. Artificial coloring is there- fore necessary. Salt. As with color, the essential thing with salt is to have it evenly worked through the butter and none of it should remain undissolved. Package. Butter should be well packed and the top covered with cheese cloth and saturated brine. The package should be neat and clean and in no way mutilated. BUTTER SCORE CARDS. The score card contains the "score" or judgment as given by the judge. In commercial judging of butter a score card is used which is quite similar to the one given below. 136 CREAMERY BUTTER MAKING BUTTER SCORE CARD. Name Sample. No. 1 2 3 Flavor - - 45 40 38 36 Texture 2 5 23 23 23 Color - 15 15 14 14 Salt - 10 10 10 9 Package - 5 5 5 5 Total - - 100 93 90 87 ^""^ ^" ~~" ^^^ Im ^ tmim Date. Judge. In such scoring no attempt is made to point out the particular defects any further than to indicate the number of points for each sample. The total number of points determines the class to which the butter belongs. Thus in the score card above, sample No. i grades as "extras/' sample No. 2 as "firsts," and sample No. 3 as "seconds." At dairy conventions and in educational butter scoring . tests the object in judging is not so much to determine the score of the butter as to point out as nearly as possible the causes of any defects and to suggest remedies for over- coming them. The score card used in this case is shown on the next page. ' CREAMERY BUTTER MAKING BUTTER SCORE CARD 137 No. (-, C be C ! o : s B 2d Scoring. Date f Curdy. Light. Rancid. Flavor 45 Fishy. { Feverish. Oily. Weedy. Stable. Unclean. f Poor grain. Texture . 25 ! Cloudy brine. 1 Weak body. [ Too much brine. Mottles. Color .. . 15 White specks. Too high. L Too light. JToo much salt. Salt 10 (Undissolved.) Poor salt. t Lacks salt. \ Dirty. Package . 5 Poorly packed. Poorly nailed. Total 100 Poorly lined. Remarks : Date. Judges 138 CREAMERY BUTTER MAKING A brief discussion of the defects indicated on this score card is given below : FLAVOR. Curdy flavor is caused by overripened starters or add- ing starters to cream while the latter is at too high a temperature. Light flavor is generally due to churning cream too sweet. It may be due also to too much washing and to the character of the feed. It is well known that good suc- culent June pasturage produces a higher flavored butter than average dry winter feed. Rancid flavor is due chiefly to overripened cream. The age of the milk, cream, and butter is also frequently the cause of rancidity. Good butter exposed to light and air at ordinary temperatures turns rancid in a very short time. Feverish flavor is noticeable principally in the spring of the year when cows are turned out on pastures and is, no doubt, due in most cases to the sudden change from dry feed to luxuriant pasturage. It is possible that this feverish or grassy odor is due partly to the grass itself and partly to a feverish condition of the cow caused by the sudden change of feed. We find that any feverish condi- tion of the cow will manifest itself in the milk and the products therefrom. Oily flavor may be caused by churning and working butter at too high a temperature, or by keeping the milk and cream at high temperatures. Bacteriologists claim that certain species of bacteria have the power of im- parting an oily flavor to butter. Weedy flavors are caused by cows feeding on weeds. CREAMERY BUTTER MAKING 139 Leeks or wild onions are frequently the cause of very serious trouble when cows have free access to them. Fishy flavor has been shown to be due to certain species of bacteria and possibly to enzymes. By inoculating good cream with cultures of these germs the fishy flavor may be produced at will. This flavor has also been ascribed to poor salt. Stable flavor is caused by lack of cleanliness in milking, and by keeping milk too long in, or near, a dirty stable. Unclean flavors are caused by dirty pails, strainers, and cans, filthy creamery conditions, and general unclean- liness in the care and handling of milk. TEXTURE. Poor grain is caused by overworking and overchurn- ing ; also by too high temperatures in churning and work- ing. Weak body is usually caused by employing too high temperatures in the entire process of manufacture, in- cluding the ripening of the cream. These high tempera- tures usually result in overripened cream, overchurned butter and consequently butter with too high a water con- tent. The character of the butter fat also influences the body of the butter. Too much brine is caused chiefly by underworking and by churning to small granules. Cloudy brine is caused by churning at too high a tem- perature and also by granulating too coarse. Insufficient washing has a tendency to produce a cloudy brine. COLOR. Mottles are discolorations in butter caused by the un- even distribution of salt. Those portions of the butter 140 CREAMERY BUTTER MAKING that contain the most salt will have the deepest color because of the attraction of salt for color. Mottles can always be removed from butter by working, but frequently the conditions are such as to require overworking to secure this end. The following are conditions that favor mottles : 1. Coarse uneven grained salt. 2. Carelessly adding the salt to the churn. 3. Butter too cold for working. 4. Using too cold or too warm wash- water. White specks are due either to curd particles in cream caused by overripening and lack of stirring during ripening, or to dried and hard- ened cream. SALT. Undissolved salt may be due to three things : 1. Poor salt. 2. Too much draining before salting. 3. Salting the butter at too low a tempera- ture. SAMPLE FOR SCORING. In -judging butter only a small sample is necessary which is secured by inserting a "trier" (Fig. 35) into the butter and giving it a w hl e turn after which the plug of butter mav b e removed. CHAPTER XV. LOCATION AND CONSTRUCTION OF CREAMERIES. The creamery industry has had a marvelous growth during the past decade and at no time in its history has it been in a more healthy, flourishing condition than it is at the present time. This growth has been the result of a gradual change in agricultural methods, necessitated chiefly by the need of conserving the fertility of lands now under cultivation. As our lands become older, an agri- cultural practice that will have for one of its objects the preservation or restoration of soil fertility, must grow more and more imperative. We have, therefore, much assurance that the creamery industry will flourish in the future as it has in the past, and that the creamery has come to stay as a permanent institution. The same care and attention should therefore be given to the location and construction of creameries that is now given to our schools, churches, and other institutions. CREAMER^ LOCATION. In deciding upon the location of a creamery, we should carefully consider the following points : ( i.) the number of cows in the community; (2) the slope necessary to insure good drainage; (3) the center of the milk producing territory; and (4) the supply of pure water. (i.) Before building a creamery we must first ascer- tain the number of cows available for its support. There should be an assurance of not less than 400 cows in a 141 142 CREAMERY BUTTER MAKING radius of five miles of the creamery to start with. Too frequently creamery "promoters" are the cause of cream- ery failures because the creamery has been placed in a territory containing too few cows. (2.) The ground upon which the .creamery stands should slope at least one foot in ten. This amount of slope is necessary for two reasons : (a) to secure sufficient drain- age, and (b) to permit the construction of a creamery with an ideal interior and exterior arrangement, such as will do away with extra can lifting, and extra pumps and piping. (3.) Locations far removed from railroad stations are undesirable. It makes transportation to and from the station too expensive. Besides, during the summer the butter is liable to get too warm before it reaches a refrig- erator car. (4.) Pure water is absolutely indispensable to the suc- cess of a creamery. Experiments have abundantly demon- strated that butter washed with impure water will be inferior in flavor and particularly poor in keeping quality. CREAMERY CONSTRUCTION. The following cuts illustrate a creamery constructed of brick with galvanized iron roof, making a creamery that may be considered fire proof. These plans have been drawn up with special reference to: I. Sanitation; II. Saving of labor; III. Durability; IV. Cost. In the con- struction of all creameries attention must be directed to these four points. CRBAMBRY BUTTER MAKING 143 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Fig. 36. Ground plan. Skim-milk can. Receiving- can. Buttermilk can. Test table. Tester. Office desk. Bath tub. Skim-milk pump. Skim-mi k can. Rack for apparatus. 11. Wash sink. 12. Ice water pump. 13. Ice water tank. 14. Buttermilk pump. 15. Ventilator. 16. Intermediates. 17. Blower or ventilating fan. 18. Butter printer. 19. Wash sink. 144 CREAMERY BUTTER MAKING 3C/U.C-FEET. Fig. 37. Longitudinal section. Fig. 38. Rear view Fig. 39. Front view. CREAMERY BUTTER MAKING n 145 Fig. 40. Side view. Fig. 41. Side view. I. SANITATION. Iii a place where human food is manufactured sanita- tion should be of first importance. But unfortunately in too many creameries this is made an entirely secondary issue. Creamery sanitation brings into consideration (i) the disposal of sewage; (2) the construction of floors and walls; (3) facilities for cleaning; (4) the construction and placing of pipes and machinery," (5) methods of ventilation; and (6) the bath room. 146 CREAMERY BUTTER* MAKING i. Purification of Sewage. The author, for several years, has made efforts to gather the best information concerning the purification of creamery sewage, a subject which deserves the serious attention of every buttermaker whose creamery is not so located as to permit a discharge of the sewage into flowing water. These studies have recently been supplemented by care- ful experimental tests, which have made it possible to write the following discourse on sewage purification with full confidence of the success of the method advocated therein. The method of purification is the septic tank, o" bo 03 a 6 o OJ 03 (J S !5 ,a ' 'rS a u P u u P^. U g 1 ^ 0* U U & 1 .^ o -5 c PQ Q Q i >M O "^ c/i c/i -i s 03 PH c^' ^ tf 00 l> D rH S QO rH Si rt 5 5 ; >- % spaao So o o , O O OS O 00 t OS 00 O t' -* I-H (M CO " 31 7 Patrons Monthly dues. 1 902 48 " 31 7 Balance To new account 197 85 $2 392 68 $ Order book page. CREAMERY BUTTER MAKL\C 245 Pay Roll Register. Each patron's monthly account is recorded in the pay roll register as illustrated below : PAY ROLL REGISTER. & a t Date, 189S. JO a i Name. 1 u Price. Amou bJD as S I O April 5 i John Smith 7,850 3.9 306.15 $0 20 $61 23 $1.48 $5975 123V " 5 2 Paul Wirth 4,575 4.0 183.00 20 36 60 3660 124V V Means paid. The Ledger. Where a good, permanent, and easily accessible record is desirable, the main items of all trans- actions should be posted under suitable heads in the ledger. Where there is liable to be a frequent change of bookkeepers the additional work involved in keeping a ledger is well justified. In case monthly payments are made at the creamery all accounts should be closed once a month and those with different individuals should be kept separate. The fol- lowing illustrates a ledger account with a butter firm in New York. Dr. John Johnson & Co. Or. New York City. Sept. 3 Balance. . .... *]9, $90 40 Sept. 6 Check 114 $80 35 " 7 Sale . ^ e > 103 38 " 18 Check 14 139 85 " 20 Sale H 84 50 " 31 Balance 14 58 08 Oct. 1 Balance 13 58 08 * Sales book page. 1 Cash book page. 246 CREAMERY BUTTER MAKING Below is illustrated a ledger account with a creamery supply house in Chicago : Dr. J. D. Murray & Co. Cr Chicago. Aug. 4 Check *15 $29 00 Aug. 1 Balance. . . 116 $18 50 " 11 Check 15 64 50 " 5 Order. 16 70 38 " 31 Balance 15 19 38 " 19 Order 16 24 00 Sept. 1 Balance 16 19 38 * Cash book page. T Order book page. The following illustrates a ledger record with a patron of the creamery : Dr. William Sampson. Cr. 1898. Piketown August ^\ Check.. $61 50 August Milk . $61 50 *18 Sept. 31 Check 83 92 Sept. Milk 83 92 19 * Pay roll register page. Milk Sheet and Milk Book. Immediately after milk is weighed it is recorded upon a milk sheet placed in the intake. This sheet consists of heavy paper with the date, name, and number of the patron upon it. The names should be arranged in alphabetical order. A suitable milk sheet is illustrated in Fig. 73. Where care is taken in recording the milk upon the milk sheet, the milk book may be dispensed with. In that case a record of the milk is preserved by filing the milk sheets after each patron's total has been transferred CREAMERY BUTTER MAKING 247 to the pay roll register. In case, however, a careful daily record of the milk is to be preserved, it is better to copy the milk from the milk sheet into a milk book in which a record may be preserved for a long time. Fig. 73. Milk sheet. Test Book. A permanent record of milk tests is made in the test book. The following illustrates the method of keeping such a record : 248 CREAMERY BUTTER MAKING Patron's name. 1898. oi -a cf I ni c. 1 vi ving without free oxygen. CALIBRATING. Determining the caliber of the neck of a test bottle in order to ascertain the accuracy of the scale upon it. CARBOHYDRATES. Substances like starch and sugar. CENTRIFUGAL FORCE. That force by which a body mov- ing in a curve tends to fly off from the axis of motion. CHEMICAL COMPOSITION. This refers to the elements or substances of which a body is composed. COLLOID Ai,. Resembling glue or jelly. CONCUSSION. The act of shaking or agitating. CONSTITUENTS. The components or elements of a sub- stance. DEAD CENTER. That position of the engine when the crank arm and the piston rod are in a straight line. DIVIDERS. An instrument used in reading tests. EMULSION. A mixture of oil (fat) arid water contain- ing sugar or some mucilaginous substance. ENZYMES. Unorganized ferments, or ferments that do not possess life. FIBRIN. A substance which at ordinary temperatures forms a fine network through milk which impedes the rising of the fat globules. FOREMILK. The first few streams of milk drawn from each teat. GALACTASE. An unorganized ferment in milk which di- gests casein. 261 262 CRHAMBRY BUTTUR MAKING INOCULATION. To seed, to transplant; as to inoculate milk with lactic acid germs. INSULATION. The state of being protected from heat and cold by non-conducting material. LEAD. The amount of opening of the steam ports when the engine is on the dead center. LOPPERED MILK. Milk that has thickened. MAMMARY GLAND. The organ which secretes milk. MEDIUM. The substance in which bacteria live. Thus, milk furnishes an excellent medium for the growth of bacteria. MENISCUS. A body curved like a first quarter moon. MILK SERUM. Milk free from fat. Thus, skim-milk is nearly pure milk serum. MIXING CANS. Small tin cans used for mixing milk pre- paratory to testing. NEUTRAL. Possessing neither acid nor alkaline prop- erties. NON-CONDUCTOR. A material which does not conduct heat or cold, or only so with great difficulty. OSMOSIS. The tendency in fluids to diffuse or pass through membranes. PARTURITION. The act of being delivered of young. PASTEURIZATION. The process of destroying all or most of the vegetative bacteria by the application of heat from 140 to 185 F. PERIOD OF LACTATION. The time from calving to kk dry- ing up." PHYSICAL PROPERTIES. The external characteristics of a body, like color, odor, hardness, solubility, density, form, etc. PROPAGATE. To continue to multiply. Thus, to propa- gate a starter means to continue multiplying the lactic MlUtY BVTTUR MAKING 263 acid bacteria by daily transferring them to a new medium such as sweet pasteurized skim-milk. PROTEIDS. Nitrogenous substances like casein and albu- men. REDUCING VALVE. A valve used for regulating steam pressure. REFRIGERANT. In mechanical refrigeration a substance whose evaporation produces cold. RENNET. The curdling and digesting principle of calf stomach. SCORING. A term used synonymously with judging. SECRETION. The act of separating or producing from the blood by the vital economy. SEPTIC. Promoting decay. SPECIFIC GRAVITY. The weight of one body as compared with an equal volume of some other body taken as a standard. SPECIFIC HEAT. The quantity of heat required to raise the temperature of a body one degree. SOLUTION. The state of being dissolved. SPORE. The resting or non-vegetative stage of certain kinds of bacteria. STEAM TRAP. An arrangement by which condensed steam may be taken out of heating pipes without the escape of steam. STERILIZATION. The process of destroying all germ life by the application of heat near 212 F. STRIPPERS' MILK. The milk from cows far advanced in the period of lactation. STRIPPING*. The last few streams of milk drawn from each teat. SUSPENSION. The state of being held mechanically in a liquid, like butter fat in milk. 2<>4 CRE. \MlikY 'BUTTER MAKING TRYPSIN. The active agent in the secretion of the pancreas. VEGETATIVE BACTERIA. Those bacteria that are in an actively growing condition. VISCOSITY. The quality of being sticky; stickiness. VOLATILE. The state of wasting away on exposure to the atmosphere. Easily passing into vapor like ammonia. WHOLE MILK. Milk which has neither been watered nor skimmed. INDEX. Page Abnormal fermentations 47 Acid, butyric 15 , oleic 14 , palmitic 14 , sulphuric 2S , amount of, for cream 2:;<> tests for cream Si. milk So , kinds of 82 , precautions in making 86 measures 27 Acknowledgments 259 Adjustment of shafts 193 Adulteration, milk 39 , detection of 39-41 Air compressor 77 Albumen 17 Albumenoids 16 Alvord, II. K, mentioned 256 Ammonia plant 237 , operating 237 Anhydrous ammonia 233 , circulation of 233 Apparatus for Babcock test 25 buttermilk distribution... 132 Farrington test 84 Manns test 82 purifying water 209 Appendix 250 Ash of milk 17 tubs 114 Automatic pipette 229 Babcock, Dr. S. M., mentioned 23. 107 test 23 apparatus 25 -, how to read 29 -, making a ". 28 - , precautions in 30 Page Babcock test, principle of 23 , sample for a 23 Bacteria 42 Bair cream cooler 67 Basis for butter judging I:M Bath room, creamery l.'O Bearings, hot 19:5 Belting from engine to separa- tor 1S9 , size of ; 191 Belts, friction as applied to.. 191 , lacing of 192 Bichromate of potash 52 Bitter fermentation 47 Boiler, steam 165 , care of . . 174 , firing of 172 - H. P. of ..178 , kinds of ...165 scale 175 , cause of 175 , objection to 176 , prevention of .176 Boyd cream ripener 76 Brine salting 109 system of refrigeration 234 Building, cost of creamery. ... .158 , cost of equipping creamery .159 Burning, definition of.. 172 Butter color 106, 139 s composition of 250 extractor 60 -fat 13 , causes of variations in percentage of 19 : 22 , composition of 14 globules 13 , influence of feed on.... 15, 16 , insoluble 14 , melting point of.... 14 265 IXDLiX Page Butter fat, physical properties of 1 13 , soluble 14 .specific gravity of 14 flavor 138 granules 107 judging 134 , marketing 117 milk, calculating amount of.129 .composition of 251 distribution 132 packages 114 packing 114 printer 116 prints 115 salting 107 sample for scoi i:;; 140 score cards 136, 137 slips 248 , texture of 139 trier .'..140 , washing of 107 . water content of 256 . working 110 Butyric acid 15 fermentation 46 By-laws of creamery associa- tion 255 Calculating amount of butter milk 129 - skim-milk 128 dividends 119 milk solids 38 speed and size of pulleys 188 - of tester 32 Calibrating milk bottles 37 Cans, starter 97 , weigh 11 ('are of milk and skim-milk 233 ( 1 asein 16 Cash book 144 Chromogenic fermentations 49 (.'burning 100 >-, difficult 112 , influences on 100 operations 105 temperature 101 Page Churning temperature, rule for. 102 . theory of 10!) Churns 103 , cleaning 112 , combined 103 , Disbrow 105 , gas in 107 , preparation of 105 , speed of 103 , straining cream into 106 . Victor 104 (Meaning churns 112 test bottles 31 Cleanliness and cleaning 258 Cocks, gauge 168 Color, kinds' of 106 Colostrum milk 18 , composition of 18 , physical properties of 18 Cooling with ice water 77 , table for 79 Composite samples 51 , care of 54 . frequency of testing 55 sa mpling 51 test jar 50 , double set of 66 Composition of butter 250 , butter fat 14 , buttermilk 251 cream 250 milk 12 skim-milk 251 Compressor, air 77 , ammonia 232 , power required to oper- ate 233 Conn, mentioned 43,46 Connecting rod 182 Contents, table of 9 Constitution of creamery as- sociation 253 Co operation 213 of butter maker and patron. 215 Co-operative creameries 213 , management of 215 , methods of organizing. . .213 Corrosive sublimate 52 INDEX 267 Page Crank, engine 182 Cream 57 acid tests 81 .adding color to 106 , ice to 80 , advantages of rich 63 bottle 25, 229 , churnability of 69 , composition of 250 cooler illustrated 205 coolers 67 - Blair 67 cooling 75 , effect of richness on weight of 228 , gathered, grading of 230 , handling of 227 , pasteurization of 231 , results of experiments in. 211 , pasteurized 71 pasteurization 200-205 , beginning of 200 , results of experiments in. 206 , richness of 63, 102 , regulation of 63 ripeners 76 , Boyd 76 , Farrington 76 , ice water attachment of. 78 ripening 68 , control of 73 , methods of 70 , natural 71 , object of 68 , starter 72 , temperature for 74 -. sampling of 227 scales 28 separators 58 , choice of 60 , De Laval 58 , durauility of 62 , efficiency of 60 , history of 58 . Reid, mentioned 59 , Sharpies f 9 e , United States, mentioned 59 Cream tester testing . . . Page ...229 , titration of 81 Creamery bath room 150 book-keeping 241 , a simple method of 242 building, cost of .....158 , illustrations of 143-145 construction 14:2 , durability of 157 , equipment, cost of 159 , heating of 163 ice house 162 intake 152 location 141 machinery, cost of. 159 mechanics 165 refrigerator 160 roof 163 sanitation 145 , saving of labor in 151 sewage 146 smoke stack 178 ventilation 149 Creaming 57 centrifugal 57 , definition of 57 , gravity 57 , processes of 57 Crosshead 182 Curdling fermentation 45 Curtis milk heater 64,65 Cylinder, engine 180 Danish Western separator, men- tioned 58 Day book 178 De Laval separator 58 Difficult churning 112 Dipper sampler 52 Disbrow churn 105 Distribution of buttermilk 132 , apparatus for 132 Distribution of skim-milk. .... .i::<* , apparatus for 132 Dividends, calculation of 119 for milk and cream, .. .126 268 INDEX Page Douglas starter 91 Duclaux, mentioned 69 Durability of separator 62 Dry steam 178 Eccentric .......182 Engine, steam 179 , care and management of .. .186 .foundation for .180 , horse power of 187 Equity sampler 52 Erricson starter 92 Eugling, quoted 18 Foundation, creamery s , engine Friction Frothing Farrington & Woll, quoted.. 32, cream ripener , test Fat, butter globules , insoluble , soluble Fermentations, milk , abnormal , bitter , butyric , chromogenic , classification of , curdling and digesting . gassy , lactic , normal , slimy or ropy , toxif Firing of boiler , pointers on , Flavor, cream , butter Foaming in churning Formalin Formula for calculating II. P of engine milk solids , size of belting 157 180 191 70 228 ,76 , 83 13 , 13 , 15 16 , 43 , 47 , 47 46 . 49 43 , 45 49 . 44 . 44 . 48 . 49 172 173 68 .138 ,112 . 52 ,187 , 3S .191 Page Gassy fermentation ^9 Gland, mammary 11 Glass gauge . 167 Globules, fat 13 Globulin 16 Glossary 261 Governor 1^3 Gravity process of creaming.. 57 Gauge cocks 168 , steam _ . . .168 Hand separators 60 Hansen's. starter 92 Hawkins, quoted 177 Horse power of boiler 178 engine 187 Ice house 162 Injector 168 , care of 170 , principle of 168 Insoluble fat 15 Intake 152 Introduction 7 Iowa station, mentioned 256 Jacobus, mentioned 171 Keeping quality of butter. ..70, 207 Keith starter 91 Kelley, H. H., quoted 237 Koenig, quoted 12 Kolarik, mentioned 52 Lacing of belts ....192 Lactic fermentation 44 Lactometer 34 . making test with 34 , precautions in 36 , reading of 34 , corrections for tem- perature in 34 , interpretation of 35 Ledger 244 Lefeldt, mentioned '. 58 Lining up shafting: 10S Location of creamery 141 INDEX 269 Page Location of engine 156 refrigerator and ice house. 156 Lubricator 185 Machinery, creamery 153 , cost of 159 Mammary glands 11 Manns' test 82 Marketing butter 117 Marshall, mentioned 95 Mechanical refrigeration 232 , charging and operating plant 237 , machines for 232 , principle of 232 , systems of 234 , brine system of 234 Mechanics, creamery 165 Methods of cream ripening 70 sampling 52 Metric system 252 Milk 11 adulteration 39 , detection of 39-41 , amphioteric reaction of 11 book 246 bottle 25 tester 30 --, colostrum 18 , composition of 12 , maximum and mini- mum 13 Milk cooler and aerator 223 fermentations 43 heaters 65 , Curtis 65 , classes of 65 , direct 65 , objections to 65 , indirect 65 , Reid 66 , Tvven tieth Century 65 , physical properties of 11 secretion 18 sheet 246 - solids . .-. 35 , calculation of 38 Page Milk, specific gravity of 12 sugar 17 , variations in quality of.... -19-22 , viscosity of 12 Monrad, mentioned 257 Monthly statements 122 Mortenson, quoted 203 New Jersey Station, quoted 21 Nuclein _. 16 Oils 193 Oleic acid 14 Order book 243 Overrun ' 1EL theoretical 128 Packages, kinds of 114 , foreign trade 116 , home trade 114 Packing 195 butter 114 Palmitic acid 14 Pasteurized butter making in America 201 , methods of 203 Pasteurization of cream.. 200 , beginning of 203 skim-milk 224 , illustrated 226 Pasteurizer and cooler 204 , Reid 66 Pasteurizers, kinds of 203 Pasteurizing cream, cost of 210 , results of experiments in. 206 gathered cream 210 , results of experiments in ..211 Pay roll register 244 Period of lactation, effect of, on milk 20 Physical properties of milk 11 butter fat .13 colostrum milk... 18 Pipes and piping 185 Pipette 27 ...229 , automatic ...* Piston, working of 181 270 INDEX Page Prandtl, mentioned 58 Preface 5 Preservatives 52 Principle of Babcock test 23 mechanical refrigeration.. 232 Print butter 115 Printer, butter 116 Process of creaming, gravity.. 57 , centrifugal 57 Pulleys, calculating size and speed of 188 Pumps 170 Purification of wash water for butter 207 , apparatus for 209 , by filtration 208 heating 208 Rate of salt 108 Refrigerating capacity 235 pipes 236 Refrigeration, mechanical 232 , systems of 224 Refrigerator 16) Reid pasteurizer fi6 separator, mentioned 59 Richmond, quoted 14, 250, 2 31 Richness of cream 63 , regulation of 63 -: for churning 102 Rule for calculating buttermilk. 129 size of pulleys .188 skim-milk k 128 speed of pulleys 188 churning temperature 101 determining H. P. of boiler 178 Russell, quoted 45,47 Safety valve 168 Sales book 243 Salt an absorbent 110 Salting 107 , brine 109 Sample, amount of, for test... 23 Samplers, milk 52 Sampling of milk, composite.. 51 Page Sanitation, creamery 145 Scale, boiler 175 , cause of 175 , objection to 176 , prevention of 176 Scovell sampler 52 Separating temperature 6] Septic tank 146 Setting slide valve 182 Sewage, creamery 146 Shafting, lining up 198 Shafts, adjustment of 193 Sharpies separator 59 Siebel, quoted 235 Skim-milk bottle 26 , calculating amount of 128 , composition of 251 , distribution of 130 , apparatus for 132 pasteurization 224 table 131 weighers 130 Skimming stations 25S Slide valve ISO , setting 180 Slimy fermentation 48 Smoke stack 178 Solids, milk 36 , calculation of 38 not fat .'.. 36 , relationship of fat and 37 Soluble fats 16 Specific gravity as affected by richness of milk 37 of butter fat 14 - milk 12 Speed of pulleys :...18S Spruce tubs 114 Starter cans 97 ripening 72 Starters 88 , acidity of 95 , carrying several 96 , classification of 89 , commercial 91 , preparation of 92 , definition of 88 INDEX 271 Page Starters, Douglas ............... 91 , Erricson ..................... 92 , Hansen ....................... 92 . Keith ......................... 91 , natural ................... :... 89 , preparation of ............. 90 , natural vs. commercial ..... 93 , object of ..................... 88 , pointers on , renewal of . . . / , selection of milk for , using of. every other day. , whole milk Steam - boiler cylinder , dry engine fittings gauge piston , wet 98 96 94 . 94 95 171 i<;:> 18:) 178 179 195 168 181 177 Storcli, mentioned ............ 88, 200 Straining cream ................. 106 - milk ............................ 224 Sulphuric acid .................. 28 S strength of ............... 28 Tainted milk .................... 219 , detection of. ............... 219 , making test for ........ ...220 Test, Babcock ................... 23 book ........................... 247 Tester, Babcock ................ 24 , calculating speed of ......... 32 , milk bottle ..... ............. 30 Testing acidity of milk ......... 85 Page Testing acidity of milk, rapid method for 85 Testing cream .227 acidity of cream 81 , pointers on 3? , supervision of 56 Thermometer scales 251 . comparison of 251 Titiation 81 of crea m 81 milk 85 Tools 194 Toxic fermentation 49 Twentieth century heater 65 U. S. separator, mentioned 59 Utensils, cleaning 25X Valve chest ISO . setting slide 182 Valves 19;; , globe 196 , parts of 197 ., repairing of 197 . kinds of 196 VanSlyke, quoted 20,37 Vessels, cleaning 258 Victor churn 104 Washing butter 107 Wash water, purification of... 207 Water content of butter 256 , methods of control- ling 257 Weigh can gate opener 11 Wisconsin curd test 220 Working butter 110 Working of piston 181 UNIVERSITY OF CALIFORNIA BRANCH OF THE COLLEGE OF AGRICULTURE THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW 5 1931 5m-8,'26 185S83 M q Mi che Is. J 1907 Creamery butter ma&ing 1 ^ /=! LIBRARY, BRANCH OF THE COLLEGE OF AGRICULTURE