‘Tf - x ‘ i Pas a 1 id RG ini ean Seren Ge r4—Te| i Tele an ae go M i as naa ws ite ys Fee eR LE thee : eT porn oie Ree ee Gil rs ‘ Pr aereatreeetes su . eR eats Bs LER eR RI LIBRARY NEW YORK STATE VETERINARY COLLEGE ITHAGA, N. Y. << GEFs > Gi¢t ot Mies Helena H. Haig btt. Digitized by Microsoft® This book was digitized by Microsoft Corporation in cooperation with Cornell University Libraries, 2007. You may use and print this copy in limited quantity for your personal purposes, but may not distribute or provide access fo it (or modified or partial versions of if) for revenue-generating or other commercial purposes. Digitized by Microsoft® Digitized by Microsoft® ite. Archibata R. Mara Digitized by Microsoft® Digitized by Microsoft® PURE MILK AND THE PUBLIC HEALTH A MANUAL OF Milk and Dairy Inspection By ARCHIBALD ROBINSON WARD, B.S..\., D. VM. Assistant Professor of Bacteriology and Director of the State Hygienic Laboratory, University of California, Berkeley, California. WITH TWO CHAPTERS By MYER EDWARD JAFFA, M.S. Professor of Nutrition and Director of the State Food and Drug Laborators University of California. WITH SEVENTEEN ILLUSTRATIONS ITHACA, N.Y. TAYLOR & CARPENTILK 1909 Digitized by Microsoft® Me age The eee Goo WS COPYRIGHT 1909 By ‘TAYLOR & CARPENTER ws 2413 Digitized by Microsoft® TO VERANUS ALVA MOORE WHOSE INSPIRING WORK AS A TEACHER AND INVESTIGATOR IN THE FIELD OF COM- PARATIVE PATHOLOGY AND BACTERIOLOGY IS EXERTING A) PROFOUND INFLUENCE IN UPLIFTING THE VETERINARY PROFESSION, THIS BOOK IS DEDICATED. Digitized by Microsoft® Digitized by Microsoft® PREFACE. The relation of milk to the public health and the means employed to ensure a safe milk supply is a subject of varied aspects. The proper control of the public milk supply requires more or less of the services of the bacteriologist, the chemist, . the physician, the veterinarian, and the progressive dairyman. The ordinary fund of technical knowledge possessed by any one of these classes is not sufficient for coping with the difficulties encountered in carrying on efficient and comprehensive meas- ures for milk and dairy inspection. Furthermore, knowledge concerning the subject is being rapidly increased by contribu- tions widely scattered in technical journals. The writer has attempted the difficult task of assembling the essential facts for the information of the health officer and others directly concerned in the crusade for better milk. The class of individuals particularly addressed is such, that a gen- eral knowledge of bacteriology is assumed to be possessed by the reader. Each chapter is accompanied by a list of references bearing on the subjects discussed. .Throughout the text, numbers in parenthesis, referring to the authorities given at the end of the chapter, have been freely used. These references serve in some cases to give statements greater weight than a mere unsup- ported personal opinion would have, and in all cases permit those particularly interested to gain access readily to the details concerning the points at issue. In the preparation of the book, the writer has become greatly obligated to his colleague, Professor M. E. Jaffa, for writing chapters X and XI. With reference to those chapters, Pro- fessor Jaffa desires to have it stated that he has not attempted to present the details of the more common methods employed in the chemical examination of milk. This branch of milk inspection is the most advanced and the methods are well estab- lished. He has been content to indicate what should be done Digitized by Microsoft® VI PREFACE. and to refer to standard works on the subject for the methods except in the case of some of the simple tests. Dr. William H. Boynton, Assistant in Pathology and Bac- teriology, New York State Veterinary College, has very gener- ously permitted the use of the photographs appearing as figures 13 and 14, together with his description of them, in advance of publication by himself. Professor G. C. Watson, General Manager of the Tully Farms, Tully, N. Y., has kindly per- mitted the use of photographs appearing as figures 3 and 4. Dr. Francis H. Slack, Chairman of the Committee of the American Public Health Association on Standard Methods of Bacterial Milk Analysis, has rendered assistance by furnishing a manuscript copy of the 1908 report of that Committee. Specific acknowledgement as to sources of information has been made largely throughout the text by means of the system of references employed. It is not safe to indulge in the hope that important work has not been overlooked, or that new facts may not require a modification of attitude towards certain troublesome problems. Therefore, assistance tending to improve the book will be gratefully received. A. R. W. Digitized by Microsoft® TABLE OF CONTENTS. LIST OF FIGURES IN TEXT ...... CHAPTER I. THE CONTAMINATION OF MILK. Udder Character of bacteria Significance Foremilk Coat of animal Exterior of udder Shape of milk pail The milker Milking machines Stable Floor Manyers and stanchions Barn improvements Feeding Special milking rooms Cleansing of utensils ' Sealding Construction of utensils Handling milk Bottling milk. Milk room. Delivery of milk . Milk flavors Sediments References CHAPTER II. CHANGES IN MILK CAUSED BY BACTERIA. Significance of bacterial contamination Numbers of bacteria in market milk Effect of temperature on bacterial growth Methods of cooling Milk during transportation . Preservation by chemicals. .. Digitized by Microsoft® XUI NW ww We — oe he SE 10 11 11 12 ¥ e 13 13 15 16 16 16 17 17 18 VIII CONTENTS. Lactic acid fermentation . ........ Putrefactive processes........0..2.2:0 cee eee ee tee Organisms causing putrefaction... Antagonism of lactic acid fermentation................ : Conditions controlling putrefaction 2000000000000 1... Source of putrefactive organisms 20.000. oe Toxic milk Ropy milk CausecOt ropy-aiille go. .9 cre occe i bcadess hale .svivaes deg daaeeene ee Biological characteristics of B. lactis viscosus Sources of contamination of milk 00 20.000 8. Means of combating ropy milk 0000 0 ee Gerniicidal activity. ......... References CHAPTER III. EPIDEMIC DISEASES TRANSMITTED BY MILK. Transmission of diseases of man by milk . Character of milk-borne epidemics eam lathes we, evtites DPN OU POV G1 ses ngcena ts A Nn Es cate ed adelante Investigations in the District of Columbia.. Importance of milk as a carrier.. ‘ Sources of the contamination of milk 000.0 oe. : Detection of milk-borne typhoid fever epidemics ....... .... Berkeley, Cal., outbreak Diplitheria Recognition of milk-borne diphtheria epidemics... _ .. Milk-borne diphtheria in Oroville, Cal.- Seatlet fevers: cue Gis! gy ; Sr cktR, 1 Stcal waar dresses Gastro-intestinal infections | .. References... a b Bn Gees Garces CHAPTER IV. BOVINE TUBERCULOSIS AND OTHER CATTLE DISEASES. Transmission by milk .... Infection of swine Insidious onset .... .. 7 Sak Conditions governing prevalence Human and bovine types of tubercle bacilli. . Digitized by Microsoft® 26 29 29 29 29 30 30 30 31 32 32 33 34 38 41 41 42 42 43 45 46 49 51 52 53 54 55 56 CONTENTS. Views of Koch | oo... : Bovine tubercle bacilli in man... ....... Intermediate types of tubercle bacilli Channels of infection 00.00... International Congress of 1908. Tuberculosis in Japan Present status of controversy Protection of the milk supply Measures against bovine tuberculosis Physical examination Tuberculin test New tests for tuberculosis - Stable sanitation and tuberculosis Tuberculin test ordinances Clean herds the goal The Washington plan Test by city official Test by any licensed veterinarian Milk contracts ; Application of the tuberculin test ‘Temporary numbers Facilitating observations of temperatures Injection with tuberculin Temperatures after injection Interpretation of temperatures Limitations of tuberculin test Fraud Permanent identification of animals Disposal of tubercular animals Disinfection Education of dairymen concerning bovine tuberculosis Anthrax Suppuration Cowpox 5 Parturition disturbances Malta fever Foot and mouth disease Milk-sickness References CHAPTER V. MUNICIPAL SANITARY CONTROL OF MILK. Control of milk supply Inspection The dairy score card Digitized by Microsoft® x CONTENTS. Improvement in Richmond, Va........ Washington milk supply ........... Educational activities _... Inspection of cows. gassed. 5 Inspection of dairy ‘apparatne es ae Inspection of water supply. ... Scope of inspection ! The score card for city wilile nisats, . Milk-borne epidemics 2... 0. 2.00 0 Temperature standard... Numerical determinations ‘ot Hinton 4 in ee atoms Education of the public .... Mh apnea Cee References ... CHAPTER VI. PASTEURIZATION OF MILK. General definition .. . er Incentives for pasteurization .. Conditions required for killing paees Bacterium tuberculosis Alteration of milk by heat. Cooked taste Alterations of milk constituents Creaming quality 00.000... Vital qualities of milk Spore-bearing bacteria... 000 00000... Bactericidal efficiency. ........... =o foe Low-temperature pasteurization.. ...... High-temperature pasteurization....... .. Commercial pasteurization ..... . EAT CICTI CY sass, , sawncntiee tian Hater. Cows shall be given fresh water at least twice daily. Calving—faxclusion from the herd. Cows shall be removed from the stable in which the herd is kept at least twenty-one days before due to calve, and not returned until seven days after calving. Digitized by Microsoft® AGREEMENT WITH DAIRYMEN. 161 Lxercise. Cows shall be permitted to exercise. They shall be cleaned, milked, and fed regularly, and always treated kindly. Long hair on the udder and surrounding parts shall be clipped. PREPARATION OF THE COW FOR MILKING. Grooming. At least half an hour before milking, the cows shall be thoroughly cleaned, and compelled to remain standing until milked. Final cleansing. Not more than ten minutes before each milking, the udders and surrounding parts shall be thoroughly cleaned by the use of moist clean cloths. ; THE COLLECTION OF THE MILK; Hours OF MILKING; METHODS OF MILKING; THE USi oF THE MILKING MACHINE. Fore-milk, he first three or four streams from each teat shall be drawn into a separate vessel and discarded. Milking shall be done in a quiet, clean, and thorough manner, and at regular hours; as nearly as possible, at twelve-hour intervals. No person not employed in the stable shall be allowed there during milking. The milking machine may be used subject to the approval of the vet- erinarian and bacteriologist. Milk to be discarded. Vf the*milk appears bloody, stringy, or other- wise unnatural, or if dirt gets into it, it shall be discarded and the pail washed and sterilized before it is again used. Milking cows excluded from herd. Cows separated from the herd shall be milked after the herd is milked or by other milkers than those employed with the herd. Cooling. Immediately after each cow is milked, the milk shall be taken to the milk room for cooling and bottling. CONDITION OF THE STABLE IN WHICH THE MILK Is DRAWN. The stable shall be kept scrupulously clean. Interior walls shall be light in color. If whitewash is used, a fresh coat shall be applied at least three times a year, and oftener if necessary, to keep the walls clean and white. Mold spots shall not be permitted. ; Tools, when not in use, shall not be exposed in the stable. The stable shall be thoroughly cleaned at least once daily. Neither this nor other work which would stir up dust or odors shall be done within thirty minutes before milking time. While cows are being cleaned, the stable shall be thoroughly ventilated, and the floor may be sprinkled to reduce the dust. At least once every two months, the mangers shall be scrubbed with a brush and soap, lye, or washing powder. Digitized by Microsoft® 162 CERTIFIED MILK. Calves, dry cows, horses, or other animals, or chickens, shall not be allowed in the stable with milking cows, nor in any adjoining apartment. No dusty or moldy hay or straw, bedding from horse stalls, or other unclean material shall be used for bedding cows. PREPARATION OF THE MILKERS; THEIR CLEANING; THEIR DRESS. A special room, conveniently located, shall be provided for the milkers to wash in before and during milking. Employees shall be clean in habits and appearance. Contagious diseases. No person having an inflamed throat, or other- wise out of health, shall be admitted to stable or dairy room. The existence of smallpox, typhoid fever, diphtheria, scarlet fever, measles, or other contagious disease on or in the vicinity of the dairy shall be immediately reported to the Commission by telephone or tele- graph, and the sale of milk shall be subject to the direction of the med- ical inspector. No person connected with the dairy shall enter a house where there is, or has been, a contagious disease, until same has been disinfected, and no person having entered such a house shall enter upon the dairy premises. : While engaged about the dairy or in handling the milk, employees shall not use tobacco or intoxicating liquors. Hands of Milkers.— Washing. Befoye milking, the milker’s hands shall be thoroughly cleaned by the use of soap and a brush, and then rinsed in clean water. He shall be careful not to touch anything but the clean top of a milking stool, the milking pail, and the cow’s teats. The hands shall be kept dry when milking. Milkers shall wear outer garments which are washed at least twice each week, and, when not in use, kept, not in a dwelling, but in a clean, ventilated place where dust does not have access‘and provided especially for this purpose. SHAPE, PREPARATION, AND CONDITION OF VESSELS FOR RECEIVING THE MILK. The milk shall come in contact with no vessel or apparatus which is not clean and practically sterile. The opening of the milking pail shall not be larger than a circle seven inches in diameter. A visor or hood to further reduce the opening is recommended. THE STRAINING, COOLING, AND BOTTLING OF THER MILK. Promptly after milk is drawn, it shall be strained through a fine wire gauze and a layer of absorbent cotton, protected on each side by a piece of cheese cloth, or an equally good strainer. Digitized by Microsoft® AGREEMENYT WITH DAIRYMEN. 163 It shall be cooled at once to 50° F. or lower, and maintained below 50° F. until delivery. No ice shall be put into the milk. The milk shall be bottled promptly, and may be bottled before cool- ing, providing this system assures cooling within fifteen minutes from the cow. Milk shall be stored only in the milk room. Water used for cooling or storage purposes shall be kept fresh and free from odor. No preservative or other substance shall be added to the milk for any purpose, and no part of the milk shall be removed; but the addition or subtraction of cream may be practiced when specially permitted by the Commission for the purpose of producing milk of guaranteed standard, provided this does not conflict with milk laws and ordinances. LOCATION AND CONDITION OF COOLING AND BOTTLING ROOM. The bottling room shall be within easy access of the stable, but so placed that it cannot easily be reached by dust or odors from the stable or yard or other source. It shall be used for no other purpose than to provide a place for hand- ling the inilk, storing clean milk utensils, and holding fresh milk pre- vious to its removal from the dairy. This room shall be entered only by persons having business thercin, and wearing clean outer garments. It shall be kept scrupulously clean. Utensils shall be promptly removed after use and cleaned in another room. The milk room shall be well lighted and screened, and drained through well-trapped pipes. PACKAGES FOR THE TRANSFER OF MILK. A flint glass bottle free from permanently attached parts shall be used for the delivery of milk. CLEANSING OF MILK CONTAINERS. All milk containers and utensils shall be thoroughly cleaned by hot water and salsoda or other equally pure agent, rinsed until the cleaning water is thoroughly removed, then exposed to live steam or boiling water at least twenty minutes, then held until used where dust and other con- taminating material will not have access. SEALS. Milk bottles shall be sealed as soon as possible after filling, and they shall not be opened before delivery. A satisfactory seal consists of melted paraffine carefully poured over the cap and impressed with date. In addition to the stopper which confines the milk, the lip of the bottle shall be protected by tin foil caps or heavy parchment paper circles. Digitized by Microsoft® 164 CERTIFIED MILK. How ARE THE Caps FoR Mik BoTTi¥ES MARKED? Caps to close milk bottles shall be marked to show the claimed quality of the milk (or cream). On the caps or elsewhere, but accompanying each package, there shall be stated the name of producer, name of dealer (if different), name of Commission, guarantee of Commission, and expir- ing date of same. ‘TRANSPORTATION. At no time between the cooling of the milk and its delivery shall its temperature be allowed to exceed 50° F. Except when the outdoor temperature is below freezing, ice shall be placed in the bottle cases. Milk shall reach the consumer within thirty hours after production. Experts employed by milk commissions. In the work of dairy inspection and examination of the product, it is usual to employ four experts, a veterinarian, a bacteriologist, a chemist and a medical examiner. ‘The compensation for their services, always paid by the dairyman, is collected in various ways. Some commissions sell bottle caps or other distinguishing devices at a price that covers the whole expense of examination, about five dollars per thousand. Others have a graduated fee roughly proportional to the output of the dairy. In other cases the dairyman pays a specific fee for each examination. Very frequently public laboratories are able to make chemical or bacteriological examinations gratis or for nominal fees. Veterinary inspection. 'The duty of the veterinarian.is to de- termine the general health of the animals, to observe the sanitary conditions and to scrutinize the technic of milk handling. In general, his duty is to determine if the conditions of the agree-" ment of the dairyman with the commission are being observed. His criticisms and suggestions must maintain that degree of alertness on the part of the foreman of milkers and other employees that shall minimize the possibility of contamination of the milk. The control of bovine tuberculosis is a task that demands the utmost vigilance. Without care in regard to this disease, the pretensions of a certified dairy are fraudulent. When not rigorously dealt with, it constitutes the greatest menace to the financial success of a certified dairy. Tuberculin tests Digitized by Microsoft® EXPERTS EMPLOYED BY MILK COMMISSIONS. 165 a year apart, with careless supervision of additions to the herd, , are useless in a herd that was badly infected at the beginning, for tuberculosis will keep pace with lax efforts directed against it. It is not sufficient to test merely the cows that happen to be in milk at the time of the test. Every dry cow should be included. In an infected herd, a test once in six months is regarded as necessary, followed each time by thorough disin- fection of the stable. The control of tuberculosis cannot be accomplished by one test carried out ina perfunctory manner, but the struggle must extend over years. Additions to the herd must be tested with tuberculin, but there is always danger that an animal, though not reacting, may introduce the disease. On this account it is far better to subject each animal added to the herd toa three months’ quar- antine with a tuberculin test at the beginning and end of this period. During the period the milk may be used. The details concerning the tuberculin test and management of the disease are given in Chap. IV. Bacteriological examinations. 'The numerical determination of the bacteria in milk is made every week and constitutes a use- ful check upon the methods employed in producing and hand- ling the milk. A low count indicates that cleanliness has been observed in the care of the utensils and in milking, and that the product has been properly refrigerated. The bacterial count is made of the milk when about the age that it ordinarily is when it reaches the consumer. Care should be taken that the sample be kept properly refrigerated until the examination is made. The samples should be taken from the dairyman unexpectedly as regards time and place. Thus it would be impossible for him to submit extra good samples with fraud- ulent intent. The numerical determination of the bacteria in milk is a good safeguard against the fraudulent sale of ordi- nary dirty milk under the guise of certified milk. There is a very wide difference in the results that are obtained by exam- ining the samples of these two classes of milk and thus fraud may be detected. The grade of milk designated *“*certified’’ should never contain more than 10,000 bacteria perce. If there is a second Digitized by Microsoft® 166 CERTIFIED MILK. grade known as ‘‘ Inspected’’ milk, it should not contain more than 100,000 bacteria per cc. in summer and 60,000 bacteria per ce. in winter. It is unfortunate and confusing to have milk commissions recognize two grades of milk. The technic of the bacteriological examination of the milk is described in Chap. VIII. Reporting on samples and keeping records of results is facili- tated by the use of a 3 by 5-inch card printed for the reception of data as follows : REPORT OF NUMERICAL DETERMINATION OF BACTERIA IN MILK. Collected! “ats. .xcsseneii sites, Geers Dat C i csnc ie cteiee FOUM sacs sissctsicdsvces : Milk drawn at... (a. Mt.) (P.M.). Plated at... ..(A. M.) (P. M.) Max. possible age ..... wo. hrs. Temperature when plated... C. Colonies per cc... ee... Condition of package... eee Chemical examinations. Chemical examinations are generally made monthly. A committee of the American Association of Medical Milk Commissions has made a report on chemical standards, which is very briefly abstracted here (3). Milk rated at 4% fat should range from 3.5% to4.5%, and 5% milk from 4.5% to 5.5%. The Babcock test is recommended, but in case of condemnation for low fat control by the ether-extraction method is desirable. Protein estimations are not recommended as a routine. It is suggested that regular tests be made for formaldehyde with the sulphuric acid-ferric chloride test, and if the test is positive, that the specimen be distilled and the distillate tested. Borax and boric acid inay be looked for by the turmeric test. Tests for salicylic acid, benzoic acid and benzoates may be made four times a year at unexpected intervals. It is recommended that tests for heated milk be regularly carried out as a check against the use of undesirable high pas- teurization temperatures, which alone can be detected by test. Acidity tests of certified milk are of little importance. Like- wise, a specific gravity standard need not be set for certified Digitized by Microsoft® THE CERTIFIED MILK PACKAGE. 167 milk. Routine tests for specific gravity should be carried out as a check against gross adulterations. Medical inspection. The health of employees and of their families offers an important field for the exercise of precau- tionary measures. In some cases, a weekly postal card report concerning health conditions is required of the dairy super- intendent. The use of diphtheria swab examinations to detect carriers of diphtheria infection about a dairy has not been adopted, but might well be seriously considered. The possibility that ‘‘ carriers ’’ of both typhoid fever and diphtheria bacilli may work about a dairy without recognition by an ordi- nary examination is a troublesome feature. The certified milk package. The fundamental idea in the delivery of certified milk is to have the milk bottles sealed at the dairy and marked with a device indicating the approval of the commission. ‘The Brooklyn commission sells the dairy- men bottle caps bearing a certification label, and illegitimate use of them may be prevented by taking care that the consump- tion of caps does not exceed the output of the certified herd. After the caps are affixed in the bottles, a layer of paraffin is placed over the cap and before it cools an impression is made with a rubber stamp, marking the date upon which the milk is to be sold and used. The stamps are the property of the commission, and contain certain private marks by which the experts of the commission may recognize the impression. The stamps are assigned to different dairymen from time to time. Other commissions issue slips bearing a statement concerning certification, which are issued to the dairymen and placed over the paper cap. Such a slip bears information as follows : ST. LOUIS PURE MILK COMMISSION. MiLkK COMMISSION CERTIFICATE. Date : Milk or cream from the dairy of. ) Behe 2 and the dairy itself have been recently examined by the experts of the Comuis- sion and found to be up tothe required standards of excellence. Another examination will be made within a month, and, if satisfactory, new label» for the bottles will be issucd dated : (Notice the date. ) Digitized by Microsoft® 168 CERTIFIED MILK. The top and lip of .the bottle are protected by an additional cap extending down over the neck. ‘This may be of tinfoil with ornamental lettering. Another device consists of a 6-inch circle or square of parchment paper crumpled around the neck and held in place by a rubber band. The paper may bear a printed label. : : Certified milk may be delivered in bulk to institutions in cans the covers of which are fastened with a lead seal distinc- tive of the certification of the commission. Amount of certified milk produced. Certified milk at present constitutes a very small percentage of the general milk supply. Dr. Coit, in his presidential address before the American Asso- ciation of Medical Milk Commissions, held in Chicago, in 1908, - made the following comment : “In New York City, the 10,000 quarts of certified milk is only one-half of 1% of the 1,800,000 quarts consumed daily, and if every quart of cer- tified milk went to a baby, which it does not, it would be Jess than 5% of all the babies in New York City, which is 205,000.”’ Certified milk has been before the public in New Vork since 1896, twelve years. The small amount consumed repre- sents the small proportion of people in the country now who realize the necessity for good milk and are able to pay for it. The figures offer subject for thought in connection with the problem of educating the public in the matter of paying twelve to twenty cents a quart for good milk. : Certified milk is producing a good effect in the various com- munities where it is known, out of all proportion to the amount of such milk produced. It has been a potent factor in arous- ing the present wave of interest in clean milk which is sweep- ing over the country but is not a response to the demand for pure milk for the masses. Fraudulent certified milk. There was an instance in Louis- ville, Ky., in which a dealer employed two physicians and a veterinarian on salaries and sold milk under their “‘ certifi- cation.’’ In another case, milk was sold as ‘‘ certified milk’’ on the basis of a falsified tuberculin test by two disreputable veterinarians. The difficulty has been met in New York State by legislative action as follows: Digitized by Microsoft® MAINTENANCE OF STANDARD. 169 ‘* No person shall sell, exchange or offer or expose for sale, or exchange as and for ‘certified’ milk, any milk which does not conform to the regu- lations prescribed by, and bear the certification of, a Milk Commission appointed by a County Medical Society organized under and chartered by the Medical Society of the State of New York and which has not been pronounced by such authority to be free from antiseptics, added preser- vatives, and pathogenic bacteria or bacteria in excessive numbers. All milk sold as ‘certified’ milk shall be conspicuously marked with the name of the Commission certifying it.’’ In Kentucky a conviction has been obtained in the Circuit Court, under the state pure food law, on the ground that the fraudulent certified milk had been so advertised as to deceive and defraud the public. It was established that the term ‘‘ cer- tified milk’’ had come to have a distinctive meaning. In Cal- ifornia, the institution of similar proceedings under the pure food and drugs act of that state induced a dairyman to stop the illegitimate use of the phrase. "Tuley (13) has discussed this problem thoroughly. Infringement in the matter of the use of the term “' certified milk’’ cannot do very much harm, for it is a simple matter for a medical milk commission to notify the profession and the public of the fraudulent nature of the claims. Maintenance of standard. That the milk produced in a number of certified dairies is really what it is claimed to be by the milk commissions controlling those dairies has been shown in an investigation conducted by the Dairy Division of the U.S. Department of Agriculture. Sixteen dairies were visited and scored by a representative of the department. The average score was 93.4 on a scale of 100 (perfection). The average score of several details was as follows : Cows, 99.8; stable, 87.2; milk house, 94.5; milking, 94.0: handling of milk, 93.0. It should be noted that the high score of the cows was based largely upon credit given for the tuberculin test required by all commissions, but which was not made by the Department of Agriculture. Twelve samples of certified milk (four days old) were scored, with an average of 86.0. The bacterial count varied from 280 to 19,000 per ce. (8). Digitized by Microsoft® 170 CERTIFIED MILK. Milk dispensaries. In France, the decreasing birth rate first stimulated an interest in agencies for decreasing the death rate of infants. One form of institution called ‘‘ consultation de nourrisons’’ is attached to maternity hospitals. Children born in the hospital are kept under medical supervision for two years. They are brought to the hospital once a week, weighed, and medical advice is given the mother. A slightly different sort of institution, goztte de /ait (milk dispensary), furnishes milk to the poor in general. In the work of milk dispensaries the aim is to decrease infant mortality among the poor by remedying methods of care and feeding. Breast feeding is urged, but when this is impossible, a pure supply of milk is provided. When the circumstances demand, the milk is modified to meet the requirements of the individual infant. Instruction in the proper hygienic care of infants is recognized as quite as important as pure food. ‘This is accomplished most effectively by oral instruction, supple- mented by educational pamphlets. Milk dispensaries are maintained in about twenty cities in the United States. In ten of these, the milk is pasteurized at various temperatures. In six cases certified milk is used and in the others milk from good sources. In general the milk dispensaries are maintained during the summer only, but in some cases they are open during the whole year. Milk dis- pensaries are maintained as charities. Nathan Straus of New York is particularly active in this form of philanthrophy. Out of the twenty cities in which there are milk depots, only four of them are maintained at the expense and under the super- vision of the health department. There are so many factors involved that it is impossible to place a valuation upon the influence of the clean milk alone, even though the work of milk dispensaries is an important factor in reducing infant mortality (9, 10). Rochester, N. ¥., milk dispensaries. Dr. Goler, the Health Officer of Rochester, N. Y., has established milk depots under the control of the health department. A contract is made for the product of a dairy during two months in the summer. A temporary laboratory is established at the farm and em- Digitized by Microsoft® MILK DISPENSARIES. 171 CIty’ OF ROCHBSTBIAR N.Y. Qverage Deaths Yader 5 Years af Gag wMonns Prior to and After The Establisiment of Mumeigal Mi Sraons — SYear Gack — mar Fig. 17. Chart showing relation of municipal milk stations to infant mortalily (6). Digitized by Microsoft® 172 ' CERTIFIED MILK. ployees of the department supervise the production of the milk, and take charge of it immediately after drawing. ‘The various modifications are made, and the product is shipped in the nursing bottles to the various city dispensing stations. ‘There are four of these stations, each in charge of a trained nurse. The instruction in the care of infants is facilitated by pamph- lets printed in English, German, Italian and Yiddish. Fig. 17 by Goler (6) shows the beneficial effects resulting from the establishment of milk stations. The work is accom- plished for a season of two months at an expense of about one thousand dollars a year. "The system of control of the pro- duction of the milk makes it possible to use raw milk (5, 6). The practicability of municipal control of milk stations has been demonstrated, and there is every reason for the adoption of this line of work by other municipalities. REFERENCES. 1. AMERICAN ASSOCIATION OF MEDICAL MILK COMMISSIONS. Pro- ceedings of the first annual session. Published by the Secretary, Dr. Otto P. Geier, 124 Garfield Place, Cincinnati, Ohio, 1907. 2. Corr. A brief history of the development of the pure milk move- ment in the United States. Paper read at the Congrés Internationale des Gouttes de Lait, Brussels, 1907. 2a. Corr. Clean milk in its economic and medical relations with special reference to certified milk. Kentucky State Medical Journal, May, 1908. 3. EDSALIL, VAN SLYKE and CHAPMAN. Report of the committee on chemical standards. Pediatrics, Vol. XX, 1908, No. 7, p. 455. 4. Grier. Our experience with certified milk in Cincinnati. Kentucky Med. Jour., Vol. VI, 1908, p. 276. 5. GOLER. Buta thousand a year. Charities, August 5, 1905. 6. GoOLER. Scheme for the sanitary control of the municipal milk supply. Paper read at the Congrés Internationale des Couttes de Lait, Paris, 1905. 7. Kerr. Certified milk and infants’ milk depots. Bul. No. 41, Ffyg. Lab., U.S. Pub. Health and Mar. Hosp. Serv., Washington, D. C., 1908, p. 565. Digitized by Microsoft® REFERENCES. 173 8. LANE. Medical milk commissions and the production of certified milk in the United States. Bul. No. 104, Bur. Anim. Ind., (. S. Dept. algr., Washington, D. C., 1908. 9. McCLEARY. Infant mortality and infants’ milk depots. London: P. S. King & Son, 1905. 10. McCreary. The infants’ milk depot. Its history and function. Jour, Hyg., Vol. IV, 1904, p. 329. 11. PARSON, LEONARD. Report of the committee on the inspection of herds and farms used for the production of certified milk. /ediatrics, Vol. XX, 1908, No. 8, p. 500. 12. Parson, R. A. Market milk: A plan for its improvement. Seventeenth Ann, Rept. Bur. Anim. Ind., U. S. Dept. Agr., Washing- ton, D. C., 1900, p. 158. 13. Tunny. Wegislation as a factor in the production of clean milk. Pediatrics, Vol. XX, 1908, No. 8, p. 487. 14. Warp. Milk production under hygienic conditions. Occidental Medical Journal, Vol. XVI, 1902, p. 178. Digitized by Microsoft® CHAPTER X. THE ANALYSIS OF MILK. Introduction. In addition to the data obtained from the sanitary inspection of dairies, the health officer should be in a position to inform himself as to the composition of the milk as sold. It is with a view to supplying such necessary aid that these two chapters are here presented. It is not intended to offer full and complete details for the analysis of milk but rather to give some simple and at the same time accurate and reliable tests for ascertaining not only the fat content but also whether or not a milk has been in any way sophisticated. For further details the reader is directed to the standard works mentioned at the end of the chapter. Composition of milk. Normal cow’s milk contains water and the four nutrients, protein, fat, carbohydrate and ash or mineral matter. Protein. Casein is the chief proteid of milk, constituting fully 80% of the total amount, the next in importance being albumen present to the amount of 15%. “The remaining 5% consists of different nitrogenous compounds, as lactoglobulin, galactin, fibrin, etc. The protein content of normal herd milk does not vary greatly, but that of individual cows has been known to range from 2.07% to 6.69%. Fat. ‘This is the most variable ingredient of milk. It does not occur in solution but is found suspended in the, form of minute globules. These vary in size not only with the milk of the different breeds but also with the same breed or individual during the period of lactation. It is a well known fact that the Channel Island breeds, Jerseys and Guernseys, yield milk showing the highest fat content and the Holstein-Friesian cattle as a rule produce milk of a low fat content. Digitized by Microsoft® COMPOSITION OF MILK. 175 The fat percentage of milk not only varies with the differ- ent breeds but also in different portions of the same milking, as shown in the following table from Aikman (1). TABLE VII. VARIATION OF SOLIDS IN DIFFERENT PORTIONS OF ONE MILKING. PORTION, FIRST. SECOND. THIRD. FouRTH. FIFTH. | sixtu. Per cent. “per cent. i Per cent. Per cent. | Per cent. | Per cent. Total solids..; 10.47 10.75 10.85 11.23 11.63 | 12.67 Fat nue Se 1.70 1.76 2.10 2.54 3.14 +.08 | 59 Solids not fat 8.77 8.99 8.75 8.69 8.49 It must be borne in mind that in mixed herds the product varies in fat percentage to a considerable degree. Some bot- tles or even cans will be unnecessarily rich in fats at the expense of others which will run below standard. This cir- cumstance may result in the condemnation of the milk, duc entirely to careless manipulation, when the average of the herd may be entirely satisfactory. The whole output of a herd at one milking is not mixed in one receptacle and then trans- ferred to cans or bottles. The usual practice is to take the milk of a few cows at a time for bottling. Even under these circumstances there is danger that the fat will rise in the vat under the cooler unless the milk is bottled immediately after cooling. Too much emphasis cannot be placed upon this important point in the handling of any milk and especially with reference to the product of certified dairies. This milk, so frequently modified for infant feeding, should be of uniform composition. The difficulties encountered are best obviated by alternating in the stable, or in the order of milking, the cows known to yield milk of high fat content with those known to give poor milk. In the case of the Channel Island breeds and the Holstein-Friesians this is a simple matter. In the case of scrub cows this recognition may not be so easy and depend- ence must be placed upon the results of the examination of the milk of these cows for fat by the Babcock test. Digitized by Microsoft® 176 THE ANALYSIS OF MILK. Carbohydrates. Milk sugar, the carbohydrate of milk, con- stitutes between 4.5% and 5% of the milk. Mineral matter. "The ash, as stated by Leach (2), does not represent the true mineral content of milk, since in the process ‘of incineration some of the constituents are altered. For instance, citric acid occurring in small quantities in normal milk will appear in the ash as carbonic acid in combination. Several other illustrations could be given. , The ash, in all probability, is the least variable of any of the ingredients of milk and for that reason is often made the basis of calculating the composition of an original milk from the analytical results of the examination of a condensed milk. Solids of milk. The protein, fat, sugar and ash comprise what are designated as mi/k solids. The sugar, protein and mineral matter constitute the solids not fat. ‘These latter, with the water, are known as the mz/k serum. The average composition of milk, its derivatives and colos- trum, are shown in the following table. TABLE VIII. COMPOSITION OF MILK, ETC. CONSTITUENTS| WATER. FAT. SUGAR. | PROTEIN. ASH. AUTHORITY. Percent. | Per cent.} Per cent.| Percent. | Per cent. Mille cesses 87.3 3.6 4.6 3.8 Pa Babcock. Skim-milk..| 90.3 zl 5.2 3.6 8 Van Slyke. Buttermilk .| 91.0 .o 4.8 3.0 7 Atwater. Cream... 68.8 22.7 4.2 3.8 5 Konig. Colostrum...) 74.5 3.6 2.7 17.6 1.6 Konig. Tifect of feeding on the composition of milk. ‘The idea is prevalent among dairymen throughout the country that the quality of the milk may be improved by modification of the feeding of the cows. The problem has been investigated many times by eminent authorities. Conclusions have been reached as follows: 1. Ifacow is being properly fed, that is, receiving a balanced ration suitable for her individual needs, the quality of the milk Digitized by Microsoft® SAMPLING MILK. 177 is not appreciably affected by an increase of any of the ingred- ients of the ration. 2. Under such circumstances fat cannot be fed into milk. Sampling milk. The first consideration in the examination of milk is the sampling. It is of the utmost importance that a representative sample be taken and too much emphasis can- not be placed on this point. Great care is called for in samp- ling milk because, as previously stated, the fat of milk is not in solution, but held in suspension, and forms an emulsion with the milk serum. The little globules of fat commence to rise very soon after milk is allowed to stand and, to the uninitiated, surprisingly fast. The writer has analyzed three different samples of milk from the same herd showing respect- ively 2.9%,9.1% and 3.6% fat. The variations were due en- tirely toimproper sampling. ‘The sample should be taken and the examination conducted while the milk is fresh and in normal condition. If the samples are to be transported to any distance previous to being tested, care should be taken to see that the bottles are completely filed. This will avoid the tendeney to churn which might cause the fat to collect in lumps and pre- vent, at times, an accurate determination of the fat. After a sample is properly taken it should be thoroughly mixed before it is tested and the respective portions for the different tests should be measured immediately after mixing. If such a practice is not adopted, scrious inaccuracies are liable to occur, owing to the rapidity with which the fat globules will rise toward the surface. By far the best way to mix a sample is to pour it from one vessel to another, and the pouring should be done on the side of the vessel and not in the center. If this precaution is not taken an appreciable amount of air will be incorporated in the milk, which will greatly interfere with the accurate measuring of the milk for the Babecek test for fat. There are on the market several different devices for sam- pling market milk, such as the Scovell, McKay, and Equity sampling tubes, ete. These with full directions for use may be obtained from dairy supply houses. Specific gravity. The specific gravity of a thoroughly mixed sample may be most conveniently taken by means of the small Digitized by Microsoft® 178 THE ANALYSIS OF MILK. hydrometer with the thermometer attached. This is about seven inches long and has a range of from 1.000 to 1.060. There are several different forms of lactometers on the market but they are not any better adapted for milk than is the hydrom- eter to which reference has just been made. All readings should be made whenever possible at 60° F. (15.6°C.). When- ever this cannot be done correction must be made in accordance with the table below, taken from Richmond (12). TABLE IX. FOR CORRECTING SPECIFIC GRAVITY TO 60°F. DEGREES OF SPECIFIC GRAVITY OBSERVED. 25 | 26 |.27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 Temperature Degrees F. Specific Gravity corrected to 60°F. | 40 | 23.5 | 24.5 | 25.5 | 26.4 | 27.3 | 28.2 | 29.1 | 30.0 | 31.0 | 31.9 | 32.8 | 33.7 42 | 23.6| 24.6 | 25.6 | 26.5} 27.5 | 28.4 | 29.3 | 30.2 | 31.1 | 32.0 | 32.9 | 33.9 44 | 23.8 | 24.8 | 25.8 | 26.7 | 27.7 | 28.6 | 29.5 | 30.4 | 31.3 | 32.2 | 33.1 | 34.1 46 | 23.9) 24.9) 25.9 | 26.8 | 27.8 | 28.7 | 29.6 | 30.5 | 31.4 | 32.4 | 33.3 | 34.3 48 | 24.0) 25.0] 26.0! 26.9 | 27.9 | 28.8 | 29.7 | 30.6 | 31.6 | 32.6 | 33.5 | 34.5 50 | 24.1 | 25.1 | 26.1 | 27.0 | 28.0 | 29.0 | 29.9 | 30.9 | 31.8 | 32.8 | 33.7 | 34.7 52 | 24.3 | 25.2 | 26.2 | 27.2 | 28.1 | 29.1 | 30.1) 31.1 | 32.0 | 33.0 | 33.9 | 34.9 54 | 24.5 | 25.4 | 26.4 | 27.4 | 28.4 | 29.3 | 30.3 | 31.3 | 32,3 | 33.3 | 34.2 | 35.1 56 | 24.6 | 25.6 | 26.7 | 27.6 | 28.6 | 29.6 | 30.5 | 31.5 | 32.5 | 33.5 | 34.4 | 35.4 58 | 24.8] 25.8 | 26.8 | 27.8 | 28.8 | 29.8 | 30.8 | 31.7 | 32.7 | 33.7 | 34.7 | 35.7 60 | 25.0 | 26.0 | 27.0} 28.0 | 29.0 | 30.0 | 31.0 | 32.0 | 33.0 | 34.0] 35.0 | 36.0 62 | 25.2 | 26.2 | 27.3 | 28.3 | 29.3 | 30.3 | 31.3 | 32.3 | 33.3 | 34.3 | 35.3 64 | 25.4 | 26.5 | 27.5 | 28.5 | 29.5 | 30.5 | 31.5 | 32.6 | 33.6 | 34.6 | 35.6 66 | 25.6 | 26.7 | 27.7 | 28.7 | 29.8 | 30.8 | 31.8 | 32.9 | 33.9 | 34.9 | 35.9 68 | 25.9 | 27.0 | 28.0 | 29.0 | 30.1 | 31.1 | 32.1 | 33.2 | 34.2 | 35.2 | 36.2 70 | 26.1 | 27.2 | 28.2 | 29.2 | 30.3 | 31.3 | 32.4 | 33.4 | 34.5 | 35.5 | 36.5 72 =| 26.4 | 27.4 | 28.4 | 29.5 | 30.5 | 31.6 | 32.6 | 33.7 | 34.7 | 35.8 74 | 26.6 | 27.7 | 28.7 | 29.7 | 30.8 | 31.9 | 32.9 | 34.0 | 35,0 | 36.1 76 | 26.9 | 27.9 | 28.9) 29.9 | 31.0 | 32.2 | 33.3 | 34.4 | 35.4 | 36.5 78 | 27.2 | 28.2 | 29.2 | 30.3 | 31.4 | 32.5 | 33.6 | 34.7 | 35.8 | 36.9 80 | 27.4 | 28.4 | 29.5 | 30.6 | 31.7 | 32.8 | 33.9 | 35.0 | 36.0 The specific gravity of milk from normal, healthy cows will vary from 1.029 to 1.035 at 60°F (15.6°C). The average for normal milk as determined by the writer from a large number of samples agrees well with the figures obtained elsewhere, namely 1.032. "I'oo much stress cannot be placed on the spe- cific gravity determination, because it is a simple matter to add Digitized by Microsoft® DETERMINATION OF FAT IN MILK AND CREAM. 179 water to milk and then some easily soluble material to bring the gravity back to the normal. Nevertheless, the determin- ation of the gravity is of great assistance to the health officer and physician. The use of the determination of the specific gravity in the detection of added water is discussed in Chap. XI. Determination of fat in milk and cream. Fat being the most variable ingredient of milk, it is only logical that all commer- cial transactions relative to milk should be based upon the fat content. It was this that gave the incentive to a number of agricultural chemists twenty*years ago, upon the establish- ment of the agricultural experiment stations, to devise a simple, rapid and accurate method for the determination of fat, which could be intelligently used by those who either had no training in chemistry or could not obtain access to a chemical laboratory. The method now in common use is the one given free to the public in 1890 by Dr. S. M. Babcock of the Wisconsin Agri- cultural Experiment Station. The details of this admirable test are hardly called for here; for such, and other valuable and useful data, the reader is referred to that excellent little work, ‘\ Testing Milk and Its Products,’’ by Farrington and Woll (5). Also, to ‘" Modern Methods of Testing Milk and Milk Products,’’ by Van Slyke (14). It may be said, however, in supplementing the directions usually given for this test that the addition of 2 cc. of an 80% solution of glycerin, as recommended by Holm (7), to the milk in the test bottle just previous'to adding the acid will insure a clearer line of demarcation than is ordinarily obtained be- tween the fat and water in the graduated neck of the bottle. Another modification which has proved useful in the testing of cream by the Babcock method is that obtained by Eckles and Wayman of the Dairy Department of the University of Missouri. It consists in dropping a small quantity of amyl alcohol colored with fuchsin or any red dye on top of the col- umn of butter fat before it is read. Since it is lighter than the fat, it floats on ‘the surface. This removes the meniscus from the surface of the fat to the top of the amyl] alcohol, and leaves a perfectly straight line across the top of the fat column. Thus Digitized by Microsoft® 180 THE ANALYSIS OF MILK. the reading of the fat is made more accurately than when an attempt is made to read either to the bottom or center of the meniscus. It is best to read the fat column immediately after the addi- tion of the alcohol, because, if the latter is allowed to remain in the fat column for several hours, it mixes: with the fat to a certain extent and the reading cannot then be taken accurately ; but this does not occur short of two hours. ‘This modification has proven of great assistance in the manipulation of the Bab- cock test for the determination of fat in cream and gives results which compare very favorably with the gravimetric method and the ordinary way of reading the fat columnin the Babcock bottle. Webster (15) has made a very exhaustive study of the testing of fat in cream by the Babcock test. In the hands of a competent operator, the Babcock test gives as reliable and accurate results as those obtained by the com- plicated ether extraction method. Interpretation of specific gravity and fat. It is almost impos- sible to lay down any hard and fast rules concerning the inter- pretation to be placed upon the specific gravity and fat content. It may be said in general with reference to milk from herds in normal condition that : a 1. High gravity with high fat content indicates a rich milk. 2. High gravity with low fat content indicates either a poor milk or that the milk has been skimmed. 3. Low gravity with high fat content indicates ‘‘top milk,’’ that is, the sample has been: taken from a quantity of milk which has been allowed to stand some time previous to’ sam- pling. 4. Low gravity, in connection with low fat content, indi- cates a watered milk. Solids not fat. While it is true in many instances that the fat per cent. and specific gravity are sufficient to enable the inspector to judge of the quality of milk, at the same time it is a simple matter to obtain the solids not fat by calculation. Formulas for such calculation have been worked out by Bab- cock, Fleischmann, Richmond and others. The one in general use in this country is Babcock’s formula. Digitized by Microsoft® TABLE X. PER CENT. OF SOLIDS NOT FAT, CORRESPONDING TO 0 TO 6 PER CENT. OF FAT, AND SPINDLE READINGS OF 26 TO 36. SPINDLE READINGS AT 60°F. 34 35 33 i ae st MON NH Saat menea coves mena coms Menns = | SSSSS5 SSSSS HARE HAAR Neininin SION ie me “| N TOO ON TOO eoauwroo ee te) lo a ~~ = a na wt — 7) o> o OID I~ Do ein I~ ned ss 38g SS Ne HATRS Boa SSOSS ZSRBSS SISSR RRKRSE SHKEDSR KERSS SBSZR Adaaa a AARADR ADAADND ADAAD DADHRAG ADADR AAAAKR AKFAR AQAAH FRADTF AHAARS Sossoo SoosoD g 2 SSSSS Saaaa A WED MO IME HReM MEOAnM S -m Oo a wo as 2 man aw Ir aa on no Nn nD ot RRRSS SESAR ASRSHS BSSAR LEANT RASA BSSSS FLAKA “eed RRRR REASBER REDE GB SOHO H GBGOHG DOWD AH AAADH AAAAH BARAAHD SARAH ADAAAH ARARH ARAGDTH AHAARH AAAHRH D Sn tO” NTO NTO O nN = Sy HOMER H—Mnwno ItSL SD TOMS Qo NATOMDD MME QDa 6 WIN Win SS3S RRERAR EREEE BaAaR oe SS igre ras NASA AEEBS a Peas WW) Wy WO CBOSS TE a COO BOD DWWOWHO DOWHO DNDODDHD HDKDKOD ADAAH AARAGRH FARAH ARAAG ARAAH DBADAH AHAHAHAH WMOFIM MEDAN WHAM rAA Nt OMSONt CMON geoudt Bann trans nRAAMO NON a RGAS8 BHSszs VIFRG BHASS VSSERR RRELE BHSS BQS2F £EREE AANGH Nad @S942 4 ear ren ON +TWOO on oo ont oO N oe ont ro =O TD TO moe = N oS a wns NAA a S8S88 SRSA SASARA BISKS SYILS BRAGS SSCSOS RAVRR HKKBE ARSSQS SSSSR ABSA A WOW OOK HW DOKHH WH WWW HKHDHH OOK KHH KON WOHD HHOKHH DHEHH HHNKHH A ADTAH AADAHR OH Wade OEDAaos wWeanno wmoeanm MrAGCM rao wnon wOeons wnoen aeons OAm9 wh ™~ = BRneKRE Bee nE mmr OO 00 00 C00 CO 00 00 30 00 080 mor oe mmown moonncn COO O; mnmnwa nmannmwe mannan wo SNTOW SaNToOe Suton SutroxX Sauyror Suwes SOU IKD 1 Par, —mwrTe fk wey ro retin ih > ey ee ba Mwnninw wwowooo Ceeem Zee RAHRRH See ee ee aa AOD Oy Py ep) Oo, at oe aS Wy WO 2 i nnnene™ Brine Con neéN hee eE Ree eE 6 ee ee Eo Oe Oe ee FH ee ee Se LB EO LNCLH LEAFS £ Mr Aas mma Wr Anwa Wm Danes wWwranO9 WD Wwrandt weer, wneronat 6 Sei Se ed ar OF aem, I~ Qi8Ss SASsy VIIHR BVARSS GOCen RHheK KLEAQH AKSSS SStra aya at nnn ne ren nenm reneem mre neMé ronneE eoeneneeE eoenee rnecnn OSC Se oe oe ER ee Se = earo ONnTOD NTO onrtoc on 10 oO onTstoe oe On WG ED ma TD =O a owes at) fis = dell SSSSE SNALA SNASR SSSRE SITLS HARKS SYSES KRGKA HYAKA ARARA SSSSE Sassy 1 NANKRN NKR NKN RK RRR RRR RR ORR RRR ORR RRR ORR RRR ORR ERE ORE OREN LH KEK LLL w aM wn ey wmwreaens mm Ans WEA wr aAns wWwesent On STN OWLONS MES SE SD vt: No i ee eo RRAKE BREZRR RRASS SSSR SAANS AAHEH BARTS YER YRECS LCRNN RELL LKFTI DF GESCSS CGEGECS SESBRK RARARKRK RRR R KR NNR RR ORR RRR ORR RRR ORR RRR ORR RRR OBO tt eonyreo onwesone enwronxr ea roc enror On TOR ICNTOS = ose wo oo Sewers aD ema aD o SRSSR SVIYSS RRRKKR FRFKE KRRFRAR SSSSE RNASA ANSSA RNGKH SHSTS BHM Seece & CECE CGSGES CGSESS GEESE CESSES RRRRR RE RRR RRR RR ORR RRR ORE RRR ORE OREO SHAME MON KA SCHNMY NONKQ GHAGVT MONAA SANyy HOMRH SANs MOmeq Tayyw wer z. F Gases esd SHAH ABH SANNN NANA cei Mime rT tT MM Mn Digitized by Microsoft® 182 THE ANALYSIS OF MILK. Table a page 181, based upon this formula and taken from Farrington and Woll, shows the solids not fat and spindle readings of 26 to 36. The spindle readings refer to the last two figures of the specific gravity ; for instance, if the specific gravity were 1.032, this would be represented in the table by spindte reading 32. It is thus seen that by adding the fat and solids not fat the total solids of the milk are obtained. In nearly all cases the difference between the actual determination of the solids not fat and the figure obtained by calculation does not differ mater- ially. ‘The inspector consequently by merely determining the fat and the gravity will be in a position to judge whether or no milk under examination is or is not up to the required standard for pure milk. Preliminary tests of milk. It is often desirable to make pre- liminary tests of milk with reference to its quality, for which there are to be obtained several devices. These are well described by Wing (6), who also gives a very interesting sum- mary of the development of the tests for fat previous to the invention of the Babcock test. : Acidity of milk. This is a point which should receive more attention from the health officer than it ordinarily does. Milk fresh from the cow will often show an amphoteric reaction but soon afterwards it will show an acid reaction and this acid- ity will vary greatly, depending entirely upon how the milk has been handled. The Committee on Chemical Standards of the American Association of Medical Milk Commissions rec- ommended that the maximum acidity of milk allowed should be 0.18 % calculated as lactic acid. The writer considers this to be a very generous standard. The acidity of milk should be determined at times but not as a routine procedure. ‘This may very easily be done by the use of the Farrington alkaline tablet test as fully described in Farrington and Woll (6). The test is very simple and does not require an expensive outlay for apparatus, but it must be emphasized that only distilled water or a clean, non-alkaline soft water should be used for dissolving the tablets. Digitized by Microsoft® FEDERAL STANDARDS. 183 A high acidity indicates bacterial changes, the result of some combination of the factors of uncleanliness, poor refrigeration and age. Federal standards. In connection with the enforcement of the pure food and drugs act, the following standards proclaimed by the Secretary of Agriculture have been adopted (13). MILK AND ITS PRODUCTS. ; a. MILK. 1. Milk is the fresh, clean, lacteal secretion obtained by the complete milking of one or more healthy cows, properly fed and kept, excluding that obtained within fifteen days before and ten days after calving, and contains not less than eight and one-half (8.5) per cent of solids not fat, and not less than three and one-quarter (3.25) per cent of milk fat. 2. Blended milk is milk modified in its composition so as to have a definite and stated percentage of one or more of its constituents. 3. Skim milk is milk from which a part or all of the cream has been removed and contains not less than nine and one-quarter (9.25) per cent of milk solids. : 4. Pasteurized milk is milk that has been heated below boiling but sufficiently to kill most of the active organisms present and immediately cooled to 50° Fahr. or lower. 5. Sterilized milk is milk that has been heated at the temperature of boiling water or higher for a length of time sufficient to kill all organ- isms present. 6. Condensed milk, evaporated milk, is milk from which a considera- ble portion of water has been evaporated and contains not less than twenty-eight (28) per cent of milk solids of which not less than twenty- seven and five-tenths (27.5) per cent is milk fat. 7. Sweetened condensed milk is milk from which a considerable por- tion of water has been evaporated and to which sugar (sucrose) has been added, and contains not less than twenty-eight (28) per cent of milk sol- ids, of which not less than twenty-seven and five-tenths (27.5) per cent is milk fat. 8. Condensed skim milk is skim milk from which a considerable por- tion of water has been evaporated. 9. Buttermilk is the product that remains when butter is removed from milk or cream in the process of churning. 10. Goat’s milk, cwe's milk, et cetera, are the fresh, clean, lacteal secretions, free from colostrum, obtained by the complete milking of healthy animals other than cows, properly fed and kept, and conform in name to the species of animal from which they are obtained. Digitized by Microsoft® 184 THE ANALYSIS OF MILK. b. CREAM. 1. Cream is that portion of milk, rich in milk fat, which rises to the surface of milk on standing, or is separated from it by centrifugal force, is fresh and clean and contains not less than eighteen (18) per cent of milk fat. \ 2. Evaporated cream, clotted cream, is cream from which a consider- able portion of water has been evaporated. State standards. In drafting local dairy ordinances it is desirable to have the standards conform to the requirements of the state law. In California, the courts have ruled that the city ordinances can conflict with those of the state to the ex- tent of raising the local standard above that adopted by the state. Collection of samples. One of the most important and weighty considerations is the proper collection of milk samples. This necessitates the employment of trained inspectors. ‘It would appear from the experience of the writer that this point is not ordinarily kept in mind when officers are appointed. The inspector should either be a dairy-school graduate well recommended or should receive the necessary training in the laboratory with which he is to be associated. Samples from milk cans, whether from store or wagon, should be collected with care in the matter of mixing as pointed out on page 177. An additional precaution regarding the use of the sampling tube might not be out of place. The tube should be thoroughly rinsed after each sample has been taken in order to preclude the possibility of contaminating one sample with traces of a preservative that might have been in the previous one. One of the most convenient receptacles for collecting milk is a wide-mouthed eight-ounce bottle with a well-fitted cork. Duplicate samples should be collected in order that the party fron. whom the sample is taken may retain one for analysis if he so desires. Dairy ordinances should require that this be done. In the case of bottled milk also it would appear to be desir- able to collect duplicate samples. This may readily be done by the inspector carrying in his outfit a clean quart bottle for Digitized by Microsoft® REFERENCES. 185 mixing samples. He would thus be enabled to thoroughly mix the contents of a sample of bottled milk in the presence of the vender and to give half to the vender as a duplicate. If this method is followed there can be no dispute as to the authenticity of the samples collected. It is highly essential that the inspector be provided with a book of numbered blank forms containing also small slips bear- ing duplicate numbers. One of these slips should go on each sample for purposes of identification. The blanks should call for information covering the essential facts regarding the source of the sample and should be in duplicate. The inspector retains the original in his book and the duplicate goes with the sample to the chemist. Allsamples must be dulysealed in the presence of the vender. This may be done by the use of gummed paper strips printed with an appropriate legend and pasted over the cork. The seal bears a printed number corresponding to that of the blank form. Sealing wax impressed with a distinctive device may also be used for the purpose of sealing the sample. In this case the cork must be flush with the top of the neck of the bottle, for the wax is smeared over both. REFERENCES. 1. AIKMAN. Milk, its nature and composition. London: Adam and Charles Black, 1899. 2. ALLEN. Commercial organic analysis. Vol. IV. Philadelphia : P. Blakiston’s Son & Co., 1898. 3. ATWATER and Bryant. Chemical composition of American food materials. ul. No. 28 (revised), Office of Leap. Sta.. CS. Dept. aler,, Washington, D. C., 1906. 4. BuytH. Foods, their composition and analysis. London: Ch. Griffin & Co., Ltd., 1903. 5. FARRINGTON and WoL. Testing milk and its products. Madi- son, Wis.: Mendota Book Co., 1908, 6. FARRINGTON. Variations in milk. Aud. No. 24, Cute. of fll. der. Eap. Sta., Urbana, M1., 1893. Digitized by Microsoft® 186 THE ANALYSIS OF MILK. 7. Horm. A new method for preventing char in the Babcock centrif- ugal determination of fat in milk and milk products. Amer. food. Jour., Vol. II, 1907, No. 7, p. 28. 8. KastLE and RoBERTS. The chemistry of milk. ul. No. 41, flyg. Lab., U.S. Pub. Health and Mar. Hosp. Serv., Washington, D.C., 1908, p. 309. 9. LANGWORTHY. Milk as food. Farmers’ Bul. No.74, U.S. Dept. Agr., Washington, D. C., 1904. 10. LEacH. Food inspection and analysis. New York: John Wiley & Sons, 1906. 11. RicHMonp. Dairy chemistry. London: Ch. Griffin & Co., Ltd. 12. RicHMOND. The laboratory book of dairy analysis. London: Ch. Griffin & Co., Ltd., 1899. 13. SECRETARY oF AGRICULTURE. Standards of purity for food pro- ducts. Cir. No. 19, Office of the Secretary, U. S. Dept. Agr., Wash- ington, D. C., 1906. 14. VaN SLYKE. Modern methods of testing milk and milk pro- ducts. New York: Orange Judd Co., 1906. 15. WEBSTER. The fat testing of cream by the Babcock method. Bul, No. 58, Bur. Anim. Ind., (. S. Dept. Agr., Washington, D. C., 1902. 16. WILEY (EpIToR). Official and provisional methods of analysis, Association of Official Agricultural Chemists. Pul. No. 107 (revised), Bur. of Chem., U.S. Dept. Agr., Washington, D. C., 1908. 17. Wrnc. Milk and its products. New York: The Macmillan Co., 1909. Digitized by Microsoft® CHAPTER XI. ADULTERATION OF MILK. Introduction. That milk is easily contaminated and subject to deleterious changes, was well known in ancient times. This is proved by a reference to the Talmudic Laws, where the fol- lowing statement is found : ‘* Milk is one of the beverages that makes the articles of food liable to receive impurities.’’ (3) It is true that chemical preservatives were not known at that time and consequently were not used. Such materials, how- ever, have been used for many years in milk intended for human consumption and the practice prevails to some extent at the present time. It may be said that perhaps few: questions concerning the public health have provoked more discussion or been produc- tive of more experiments and investigations than that of the use of preservatives in foods intended for human consuniption. It is of more than passing interest, and certainly a matter of congratulation, to be able to say that the greater the advance of science, the greater and more powerful is the ammunition brought forward to fight, and successfully too, the advocates of the use of deleterious materials in our food products. These substances, as is well known, are added in many cases for the purpose either of enhancing the value of poor products or preventing or arresting the decay of an already unwholesome food. The literature abounds in records of investigations of the influence of preservatives on the food value of milk. Fora very complete bibliography of this subject, the reader is re- ferred to Kastle and Roberts (4). Much has been written on both sides of this all-important question. If proper care is exercised in the handling of milk Digitized by Microsoft® 188 ADULTERATION OF MILK. intended for human consumption, there is no necessity for the use of preservatives to insure its keeping fresh. This is particularly to be emphasized in the care of milk to be fed to infants and invalids. While there is much evidence in favor of the use of some of the preservatives for milk, such as boric acid or borax, formal- dehyde, hydrogen peroxide, etc., yet most of this evidence is the result of artificial digestion experiments. It is conceded that such investigations are of great scientific value but too much importance must not be attributed to them. There are many conditions which obtain in the natural process of diges- tion which cannot be duplicated under artificial conditions. A notable instance of the necessity of conducting both the arti- ficial and natural digestion experiments before drawing any final conclusions is recorded by Wiley (6) in his report on the influence of salicylic acid and salicylates on digestion and health. Wiley states in his conclusions : ‘“'The’ data show very clearly that salicylic acid and salicylates appear to exert an exciting influence upon the activities which take place in the alimentary canal, stimulating the organs to greater effort, and this stim- ulation leads at first to increased digestion and absorption of the foods which are introduced into the stomach. In the light of the data which are exhibited, salicylic acid imay be said to increase the solubility and absorption of the food in the alimentary canal, so that large parts of the nutrients taken into the stomach actually enter tlre circulation. ‘“The data which show the effects just noted also indicate that the general effect upon the system is depressing, in that the tissues are bro- ken down more rapidly than they are built up, and thus the normal metabolic processes are interfered with in a harmful way. The admin- istration of the salicylic acid is attended by a gradual decrease in the weight of the subjects, altho the quantity of food elements administered during the preservative and after periods is slightly increased, which fact, together with a greater degree of absorption of the food elements, should have resulted in a slight increase in weight. This increase in weight, however, does not occur, and the disturbing influences of the salicylic acid upon metabolism, altho not very great, are specifically demonstrated.’’ The natural inference from an artificial digestion experiment, along the lines indicated, would be that salicylic acid is a Digitized by Microsoft® INTRODUCTION. 189 help rather than a hindrance to digestion of proteids, whereas the inference from the natural digestion experiment is just the reverse. It isadmitted, of course, that it is almost impossible to con- duct metabolism experiments with infants as subjects, and they are the very class most concerned. Among the many experi- ments carried on with very young animals are those of Annctt (1). The subject of his experiments were kittens three weeks of age. The milk fed was treated with boricacid. The amounts for the two experiments were respectively 40 and 80 grains of boric acid per gallon of milk. At the end of the four weeks, all kittens fed on the adulterated milk were dead, while the con- trol lot, which were fed pure milk, were alive and healthy. This series of experiments was followed by a similar one, the milk, however, being treated with formaldehyde in place of boric acid. The results of the latter experiments were not so conclusive as were those obtained from the boric acid test. At the same time, the data obtained are of more than passing interest. In the first experiment, the milk contained 7 parts formaldehyde to 50,000 parts milk. In the second experiment, the proportion of formaldehyde was just doubled, or 1 to 25,000. In the third experiment, the proportion of formaldchyde was again doubled, or 1 part to 12,500. It was noted that the gain in weight in all three experiments bv the control kittens receiv- ing only pure milk was far ahead of the gain of those receiving the adulterated article. This is particularly emphasized in the third experiment. These results are at variance with many of the findings recorded for artificial digestion experiments but as they have stood the test of criticism and investigation they must be accorded serious consideration. It is perhaps gratifying to know that Annett’s views on this subject are ably supported by the reports of Wiley (6) on the influence of food preservatives and artificial colors on digestion and health. The subjects of Wiley’s experiments were all healthy young men, and it was clearly shown that the preserv- atives studied, viz., borax, salicylic acid, sulphites and benzoic acid, and formaldehyde, were deleterious substances and _pro- duced digestive disturbances. Digitized by Microsoft® 190 ADULTERATION OF MILK. In view of the contradictory mass of évidence which is at hand as shown by Kastle and Roberts (4), it would appear that laws forbidding the use of preservatives in milk intended for human consumption are certainly to be recommended as safeguarding the public health. The strong, healthy stomach may and can withstand strains to which the delicate digestive organs of an infant or invalid would succumb. Tests for preservatives. A complete examination of a sample of milk for preservatives would include tests for boracic acid and its compounds, formaldehyde, fluorids, benzoic acid and its compounds, salicylic acid and salicylates, peroxide of hydro- gen, ete. Such thorough analytical work can be conducted only in a well-equipped laboratory. It is assumed that the man in charge of the work is an expert and has at his disposal the necessary standard works describing the tests. For this reason it is not considered necessary to reprint the methods for making such determinations. The preservatives most com- monly used are borax and formaldehyde. It is fortunate that there are simple and reliable tests for these two. Borax. A preliminary test may be made for boric acid and borates by immersing a strip of turmeric paper in about 100 cc. of milk to which about 7 cc. of concentrated hydrochloric acid has been added. If boric acid or borax is present, the paper on drying will acquire a peculiar red color which is changed by ammonium hydrate to a dark blue-green but is restored by acid. The above mentioned reagents can easily be obtained at a drug store. A positive reaction would indicate the presence of borax but a negative reaction might not in all cases mean that the material does not contain borax but would require further examination where better laboratory facilities could be ob- tained. Formaldehyde. ‘This is without doubt the best preservative of milk. So efficacious is this material that there are many compounds to be found on the market under various names, such as ‘‘callerine,’’ ‘‘freezine,’’ etc. These different prepar- ations are weak solutions of formaldehyde, ranging from about 3% to 7% in strength. Digitized by Microsoft® WATERING OF MILK. 191 There are two different methods which are easily carried out,—those of Hehner and Leach. HHehner's test for formaldehyde : ‘To 10 cc. of milk in a wide test tube add about half the volume of concentrated commercial sulphuric acid, pouring the acid carefully down the side of the tube so that it forms a layer at the bottom, without mix- ing with the milk. A violet zone at the junction of the two liquids indi- cates formaldehyde. ‘The coloration produced depends on the presence of a very small amount of iron. For this reason the ordinary commercial acid used in the Babcock test answers well for this test. However, if an excess of formaldehyde is present in the milk, this test will not indicate the presence of the preservative.’’ Leach's test for formaldehyde : ““Conunercial hydrochloric acid (specific yravity 1.2) containing 2 ce. of 10% ferric chloride per liter is used as a reagent. Add 10 ce. of the acid reagent to an equal volume of milk in a porcelain casserole, and heat slowly over the free flame nearly to boiling, holding the casserole by the handle, and giving it a rotary motion while heating to break up the curd. The presence of formaldehyde is indicated by a violet color- ation, varying in depth with the ammount present. In the absence of formaldehyde, the solution slowly turns brown. — By this test 1 part of formaldehyde in 250,000 parts of milk is readily detected before the milk sours. After souring, the limit of delicacy proves to be about 1 part in 50,000."’ The porcelain casserole can be obtained at any chemical sup- ply house and the solution as indicated can very easily be made up by any druggist. In place of the gas flame, an alcohol lamp may be used. A word of caution must be mentioned with reference to this test, because it is so delicate. In at Icast one instance the use of absorbent cotton in a strainer at a good dairy resulted in the finding of formaldehyde in the milk. Investigation showed that the cotton had been sterilized with formaldehyde by the manufacturers. The use of formaldehyde in the tubes of milking machines offers like possibilities for the contamination of milk by this chemical. Watering of milk. One of the more common sophistications of milk is the addition of water. Such a practice is not only a pecuniary fraud but it both lowers the nutritive value and may prove at times to be a menace to health, as discussed in Chapters III and V Digitized by Microsoft® 192 ADULTERATION OF MILK. The effect of the added water is to lower the specific gravity and also the percentage of all the ingredients. The determination of fat alone is not sufficient to indicate in all cases whether or not water has been added to milk. This could be illustrated by many instances, notably in the case of Jersey milk containing 6% fat. Such milk could be diluted with 50% water and at the same time yield 4% fat. Judged by the fat content alone, the watered milk would be considered of high quality, while the nutritive value would be only two-thirds of the normal. Serious mistakes have been made by modifying for infant feeding just such watered milk, upon the assumption that it was a normal milk containing 4% fat. The determination of the specific gravity when the only sophistication of the milk is that of added water, is of great value. THE STABLES. . Dairy cattle should be kept in a stable, preferably without cellar or storage loft, and where no other animals are housed. . The stable should be light (4 square feet of glass per cow) and dry, with at least 500 cubic feet of air space per animal. It should have air inlets and outlets, so arranged as to give good ventilation with- out drafts of air on cows. . The floor should be tight and constructed preferably of cement ; walls and ceilings should be tight, clean, free from cobwebs, and whitewashed twice a year. Have as few dust-catching ledges, projections, and corners as possible. Allow no dusty, musty, or dirty litter, or strong-smelling material in the stable. Haul manure to field daily, or store’ under cover at least 40 feet from stable. Use land plaster daily in gutter and on floor. Digitized by Microsoft® 10. 11. 12. 13. 14. 15. 16. 17. 19. 20. APPENDIX E. 213 MILK House. Have a light, clean, well-ventilated, and screened milk room, located so as to be free from dust and odors. Milk utensils should be made of metal, and all joints smoothly sold- ered. Never allow utensils to become rusty or rough inside. Use them only for handling, storing, or delivering milk. To clean dairy utensils, use only pure water. First rinse the uten- sils in warm water. ‘hen wash inside and out in hot water in which a cleansing material has been dissolved, and rinse again. Sterilize with boiling water or steam. Then keep inverted in pure air and sun, if possible, until wanted for use. MILKING AND HANDLING MILk. Use no dry, dusty food just previous to milking. The milker should wash his hands immediately before milking, and milk with dry hands. He should wear a clean outer garment, kept in a clean place when not in use. Tobacco should not be used while milking. Wipe the udder and surrounding parts with a clean damp cloth im- mediately before milking. In milking be quiet, quick, clean, and thorough. Commence milk- ing at the same hour every morning and evening, and milk the cows in the same order. If any part of the milk is bloody, stringy, or unnatural in appear- ance, or if by accident dirt gets into the milk pail, the whole should be rejected. . Do not fill cans in the stable. Remove the milk of each cow at once from the stable to milk room. Strain immediately through cotton flannel or cotton. Cool to 50°F, as soon as strained. Store at 50° F. or lower. Never mix warm milk with that which has been cooled, and do not allow milk to freeze. A person suffering from any disease, or who has been recently ex- posed to a contagious disease, must remain away from the cows and the milk. Digitized by Microsoft® A Acid-fast organisms..........--0....-.. 154 Acidity of milk ... Tests for ..... Actinon1ycosis a Adulteration of milk... 187 Aeration of milk................ 15, 17, 25 Amer. Asso. Med. Milk Com- missions .......... 157, 158 Amer. Pub. Health Asso...141, 152 Ammonia refrigeration. . Analysis of milk... PASAT KAR 3s ans caysuedsaaiert esheets ths Apparatus, inspection of Artificial digestion experiments 188 Aseptic milking 2.0... 4, 8, 37 ASTI Of SIMS, oe echo none ne tne 176 B Bahbeocl: teSt occ o scouts Seach 179 Bacillus coli communts..27, 55, 152 Bacillus diphthert@ ..... 0...... 52, 115 Pacillus lactimorot 0.00 Bacillus lactis viscosus.. Pacillus prodigtosus. .... Pacillus proteus 33 Pacillus pseudo tuberculosis ......154 Bacillus subtilis ccc. ec ee 29 Pacillus typhosus, carriers of, 45, 49 Effect heat upon ...... 0.0.0.2... 115 Examination of milk and water for... 46, 152 Germicidal action upon ......... 36 Jnr eager the, gt! 45 Bacteria, effect of temperature OI day reracncancaih ates 24, 34 Growth of... In foremilk. . In milk 20... In udder .. Killing of | Microscopic determination Olea cence) ae wake 151 On udder... 3, 4, 6 Spore-bearing .. .... ..116 Bactericide 00.00. 115, 117 Bacteriological examination of milk 141, 165 Numerical determinations pen Sane 110, 141 Interpretation of results......150 Bacterium acidi lactici....27, 28, 133 Bacterium diphtheria, in milk....52 Effect heat upon... 0... Examination milk for......... Bacterium lactts @et@i........00--- Bacterium lactis aerogenes....27, 36 Bacterium tuberculosis (see tubercle bacilli) Barns, improvement of.................. 11 Sanitation of... 11 Barn-yards se0 Beet pil p.-c.cy isa eot es eek Benzoic acid -......... eee eee 166 Berkeley, Cal., tuberculin test ordinance .......... 76, 195 Typhoid epidemic in............. 49 Bicarbonate of soda —...0.0002.2 192 Blended milk, Federal standard 183 Bloody milk we 138 Boran........... 188, 190 WESt TOPs csossot terteeste are 166 Boric acid ...188, 190 Boston, bacteria in milk of... 24 Milk inspection in ...... .-111 Bottle cap oo... ...167 Sterilization of. . Varieties of...... Bottled milk..... Bottles. Bottling machines.. : Bovine tuberculosis _...... 59, 60, 164 Education concerning............ 8. In swine _......... Measures against - Milk-borne 2.000... Physical examination for Prevalence of... Views of Koch on. Brewers’ grains 00... 12 Budde’s method of preserving I ac pone etl 26 Bur. Anim. Ind., score card of series Aee eset ete 95, 107 Buttermilk, Federal standard....183 Digitized by Microsoft® INDEX. Cc Carbohydrates 176 1 i { Carbon dioxide refrigeration _ 25 Carbonate of soda. 2 Ol eek Brinn NOD, Care, of cow's coat ...... =, 0 Milking machines. . © 9 Stables 11 Udder Heeb tos 6 Utensils _.13, 33 Casein in milk 2. 0.0 |... ‘174 Cells, tests for (see leucocy tes) Certified milk 74, 156 Amount produced 168 Certification label 167 Cheniical examinations 166 Cost. | . 168 Fraudulent 168 Package 167 Sanitary requirements of dairymen........ 158 Standards for . .. 169 Charbon (see anthrax ) Chemical examination of milk 166 Chemicals as preservatives 26 Chicago, pasteurization in 121 Tuberculin test ordinance Sate . . 76, 200 City milk plants, score card 108 Coat of cow 5 Collection of samples 184 Coloring matter 193 Colostrum ... 2... 387 Commercial pasteurization 118 Coninissions, milk 156 Experts of 164 Field of ........ 157 Source of authority . 167 Composition of milk 174 Effect of feeding on. 176 Condensed milk, Federal stand- ard ay 83 Contamination of milk, 1, 2,6, 45, 62 Significance 23 Continuous-flow machines 120 | Contracts, milk. 16 Control of milk supply 93 Cooked taste of milk ___....... 115 Cooling milk 15, 25,37; 121 Cowpox ees 87 Cream, alteration by heat... 116 Thickening of 193 Cream, Federal standard ... 184 Cream, evaporated, Federal standard 184 D Dairy Division, work of .102, 169 Dairymen and commissions 158 Dehorning . .) «.... ..86 Delivery of milk... 16 Diarrhea, death rate - 95 Epidemic ee 56 Digestion experiments . 78 188 Diphtheria, milk-borne ._....... 51 Bacilli (see Bacterium) In Oroville, Cal. . 53 Swab examinations ..... 167 Diseases of man transmitted by milk 41 Disinfection of stables 85 Dispensaries, milk 170 Distillers’ grains 12 District of Columbia, typhoid in “42, 47, 123 Doane-Buckley test 129 Duluth, Minn., tuberculin test ordinance 76, 206 E Education, of dairymen 85 Of public 112 Epidemic diarrhea 56 Epidemic diseases and pasteur- ization 123 Epidemic diseases transmitted by milk 41, 109 Evaporated milk, Federal standard 183 Examinations, bacteriological 165 Chemical 166 Experts of milk commissions 164 F Fat, in certified milk 174 And specific gravity 180 Babcock test for 179 Determination of 179 , Federal standards .. 169, 183 Feeding, effect on composition of milk 176 Feeds 12,17 Fermentation, lactic acid | 26 | Filth 5, 33 Flavor of milk V7 ' Foot and month disease 88 Foremilk, bacteria in : : 5 ' Formaldehyde 166, 189 Leach's test for.. 191 France, dispensaries in... 170 | Fraudulent certified milk 168 Tuberculin test 80 Digitized by Microsoft® 216 INDEX. G Stokes! ..2c.ccccsaeerennes chests 126 - : . ; ‘Trommsdorff’s.. Gastro-intestinal infections... .. 55 | Live stock industry Germicidal activity ......... -- 24, 34 | Low-temperature pasteuriz- Goat’s milk, Federal standard..183 AtioTies Patel Oo 117 Goat’s milk and Malta fever... .87 u M Handling milk............ Heat, effect on cream. _. Effect on milk ...... .... Heated milk, tests for Heating (see pasteurization ) _Hehner’s test for formaldehyde 191 High-temperature pasteuriz- BLO Mes Aue, ape sonusstiies 118 Hydrogen peroxide ...... ....193 Hyfoderma bovis .. seen 86 I Identification of animals... ...75, 80 Indemnification fer slaughtered . cows face Sop ete Infant feeding and pasteurized milk 22.0 ses sun122 Infant mortality. =... 55, 171 Infection, tuberculous ©... 2... 65 Infectious diseases, blank for reporting... 0... 211 Inspected milk . 74, 93, 112, 166 Inspection, of city “milk k plants .. 106, 111 Cows.... eects _ 105 Dairies 00 eee 93, 123 Dairy apparatus . 105 Water supplies........ 0... ....106 Inspectors, qualifications Oued 93 Intern. Cong. on Tuberculosis ... 66 J Japan, tuberculosis im... 66 K IXoch, views on tuberculosis... 64 L Lactic acid fermentation .... ....... .26 Leach’s test for formaldehyde ..191 Leucocytes in milk Standards for. Leucocyte tests _.. Doane-Buckley’. Savage’s Slack’s a ee Stewart? S$... ee ‘Milk commissions Malta fever .......... : Mammitis in cows Mangers rere Manure, disposal of...... Tubercle bacilli in ... Market milk, bacteria in .............. 24 ‘Tubercle bacilli in ......022.0.....- 63 Medical inspection, certified HOLES &. deietereeene ae Micrococci in milk......... Micrococcus lactis varians.. Micrococcus melitensts ........ Micrococcus pyogenes aureu. Microscopic estimate of bacteria 151 Microscopic tests of milk............ 126 Milk, adulteration of .... Milk-borne diphtheria.........00......... 51 Milk-borne epidemics .......... 41, 109 Milk-borne scarlet fever.. Experts of 0... Milk, composition of .. Milk, contamination of 1, 2,6, 45, 62 Milk’ dispensaries 170 Milk, Federal standard. ..183 Milk flavors 00.0.2... alt Milk, handling of... 15 Milk pail, shape Choe 7 Milk room ..... é Milk sediments ........ Milk-sickness . ..... .. 88 Milk, watering of... ... _191 Milker: 2. sc ececcccoes 8 Milking machines 8 Mineral matter .. Municipal sanitary Santen of ATI osc Feccoiaecceascs 70, 93 Of dastcarization a . a: 123 Of tuberculin test 00000000... 75 Mycotic stomatitis ..0.0000 00. 88 N New York, blank for infectious CiSeases ©... 121 Pasteurization in.... 2.0.0.2... 121 N. ¥. S. Coll. of Agri., score CATA nar onsiimritecse ern 97 Numerical determinations (see bacteriological examination) Digitized by Microsoft® INDEX. 217 oO Scores of certified dairies... . 169 Ordinances, tuberculin test 72, 85 peo oo mn Richmond 103 Berkeley, Cal... . 76, 195 In W ete. D.C... 104 Chicago, Tl... - 76, 200 | Sediments in milk 17 Duluth, Minn. .... 76, 206 + Washinet D.¢ ' Skim milk, Federal standard _ 183 ashington, 1). C. 73 | Skim milk, condensed, Federal P standard _. . 183 Skimmed milk, indication of _ 180 Palo Alto, typhoid epidemic in 46 | Skimming, tests for 192 Parturition disturbances 87 | Slack's test . 128 Pasteurization of milk 71,74, 114 | Slaughter of tubercular cows 84 Commercial . — 118 | Solids of milk 175 Continuous-flow ..... 120 | Solids not fat 180 Efficiency of....... 119 | Sour milk as food 28 High-temperature ........... 118 | Souring of milk 26, 29 In Chicago ........ . 121 | Specific gravity 177, 180 In New York .. . 121 | Spore-bearing bacteria 116 In Washington... .. 73 | Stables, dairy 10 Low-temperature 117 Sanitation of 72 Machines for ....... ..117 | Stanchions 11 Pasteurized milk, Federal stand- Standards, Federal 169, 183 ard ... 183 | Standards, state 184 For infant feeding. . 122 | Staphvlococcus progencs aureus Phagocytosis Sect .. 36 (see Jicrococcus pvo- Physical examination for tuber- LENES AUICHS) culosis 68 | State standards 184 Preservatives. ; 26, 187 | Sterilization of milk 114 Tests for... ...... 166, 190 Of utensils 13 Protein .. : 174 | Sterilized milk, Federal stand- Pus cells in milk 135 ard 183 Putrefaction 29 | Stewart's test lla Stokes’ test 126 Q Strainers 15 ae es Te : Strainer pails 7 Qualitative determinations 154 Straining, effect of 8,17 R Streptococcus in yastro-intes- ' tinal infections 35 Refrigeration (see cooling) In maninitis 4, 126 Richmond, Va., score card 103 In milk. , 4,133 Rochester, N. Y., milk dispen- _ Determination of 7 154 earies 170 | Streptococcus lacticus — 26, 27, 133 Rooms, special milking 12 Streptococcus Prvogenes : Ropy milk 30 | Strippings : 7 Sugar-beet pulp 12 Ss Suppuration 86 ‘ . 12m pe _ | Swine, tuberculosis in 60 St. Louis, certified milk in 167 Salicylic acid 166, 188 _ T Samples, collection of 184 | Sampling milk 177) Taints in milk 15,17 Sanitary control of barns 11.) Temperature, effect on bacterial Of milk 93, 158 | growth 24, 34 Savage's test 131 | Interpretation of 79 Scalding of utensils 13°, Temperature standard of milk 109 Scarlet fever, milk-borne 340) Temperature in tuberculin test Score card 94,97, 107 77, 79 Digitized by Microsoft® 218 Tests, Babcock’s .... Doane-Buckley ... ... Hehner’s...0. | Leach’s ..... Microscopic.. 125 Municipal 0000... ho SavaSe’S: vices iam. costed OT SACKS 3 renin irarcomicowas 128 Stewart’s .. 127 Stokes’... .. 126 Trommsdorff's......000000........131 Tuberculin (see tuberculin test) Thickening agents oo... 193 Time in pasteurization 117 Toxic milk. 20. 30 TOX1US ee 55 Transportation of milk 0... 25 Trommisdorff’s test 0000... 131 ‘Tubercle bacillus, bovine in man 64 Effect of heat upon ... ........ 115 In manure... is abe axessnae OO In milk. 62, 63, 153 MEY PES MOR catennegtnaes rueyisen Seren OO) Tubercular animals 84 Tuberculin 71, 77, 79 Tuberculin test... 71, “72, 75, 165 Application of... ..... shh Limitations of... .. , 79 Ordinances (see ordinances) Tuberculosis, and milk supply....67 BOVINE: veces. ceesocasseszescun caccters oo Channels of infection. Disinfection for. . In Japan ........ In swine 2... International Congress on....66 Measures against 2.0.00... 67 Milk-borne......00. 59, 64 Of Md ek se scen alts ee tesnes 69 Prevalence .... 61 Stable sanitation 72 DeSts: fOr" icso3u sense cbewlece 71 Typhoid fever... 42 And pasteurization eee Bacillus... 45, 152 Epidemics. 0.00.0... 46, 49 Milk-borne................ ....42, 123 U Udder, baeteriain. ...........1,7 Cleansing of.. 6 Contamination ‘from exterior. 6 Diseases of... ........ 86, 126 Tuberculosis of..................62, U. S. Dept. Agri., poster .......... 212 Utensils, cleansing of... .. 13 Construction of » sgl Inspection of... 00... 105 Vv Veterinary inspection ...... .. 164 Vital qualities of milk... ... ..... 116 WwW Washington, control of tuber- CUOSIS pecs coon atesisp eines 73 Milk supply... 24, 73 Pasteurization . ...123 Score card... ..104 Water supply ot dairies 106 Watered milk, indication of....... 191 Digitized by Microsoft® Digitized by Microsoft® The Pathology and Differential Diagnosis of Infectious Diseases of Animals By Veranus Alva Moore, B.S., M.D., Professor of Comparative Path- ology, Bacteriology and Meat Inspection, New York State Veterinary College, Cornell University, Ithaca, N. Y. With an introduction by Daniel Elmer Salmon, D.V.M., former Chief of the Bureau of Animal Industry, United States Department of Agriculture. The Profession will gladly welcome this new book, which brings the subject right up to the present state of the wonderful progress made in the study of infectious diseases. 8 The book deals with the important infectious diseases of animals that occur in this country.— Am. Vet. Review. Dr. Moore has rendered an invaluable service in bringing together in convenient book form a lucid, interesting and accufate account of the infectious diseases of animals. — Am. Bed. This is an indispensable book to the student and the practitioner alike. In the recent revision, Dr. Moore has amplified the text and incorporated many new facts pertaining to the pathology and diagnosis of the infectious diseases of animals brought out by the activity in the study of comparative pathology and bacteriology. * * The book is con- cise and comprehensive. We commend it to the student and to the practitioner. —Am. Vet. Review. Third Edition. Revised and Enlarged. $4.00 net Postpaid. TAYLOR & CARPENTER VETERINARY PUBLISHERS AND BOOKSELLERS ITHACA, N. Y, Digitized by Microsoft® General Surgery Y DR. MED. EUGEN FROHNER—Professor in the Royal Veterinary High School in Berlin. Authorized Translation from The Third Revised Edition, by D. HAMMOND UDALL, B.S.A., D.V.M., Associate Professor of Surgery and Obstetrics, Ohio State University, Columbus, Ohio. The translation of Frohner’s General Surgery has been undertaken to meet the need of an English text-book on the subject. This text-book is Vol. I] of a hand book of seven volumes written by various authors and edited by the late Prof. Joseph Bayer, of Vienna and Prof. Eugen Frohner of the Berlin Veterinary School. One other volume of this hand book, De Bruin’s Obstetrics, is already well known to English speaking veterinarians. The reputation of Prof. Frohner as a writer of text-books is too well known to require explanation. This translation is from the 1905 edition; the subject is presented in a scientific manner; is both concise and com- plete, and based on the experience of many years of carefully prepared statistics from the largest clinic of its kind in the world. “The translator has earned our thanks for making available to non-German read- ing Veterinarians one of the best of the numerous works on General Surgery. The name of Professor Froliner is a sufficient guarantee of the excellence of the matter and the convenience of ils arrangements. ‘The work contains much information not to be found, or indifferently treated of, in others of the same class and some chapters, not. ably those on tumour, fractures and luxations, are admirably written.” ‘THE JOURNAL OF TROPICAL, VETERINARY SCIENCE, Calcutta “TY beg to thank you for the copy of Frohner’s General Veterinary Surgery which I received from youa short time ago. It is an excellent work, the best of its kind, in my opinion, in the Kuglish language. (Signed) J. J. (CONNOR, M.RLG. Vi Professer of Surgery, Royal Veterinary Colleye of Ireland. “The original work of Frohner is of course of an unusually high class and T have found your translation of it highly satisfactory. You have rendered a distinet service to veterinary students in America by your admirable translation of this work which in excellency is unsurpassed in Veterinary literature. (Signed) W. LL. WILLIAMS, Professor of Surgery New York State Veterinary College, Ithaca, N.Y." $3.00 net Postpaid. TAYLOR & CARPENTER VETERINARY PUBLISHERS AND BOOKSELLERS ITHACA, N. Y. Digitized by Microsoft® Veterinary Doses and Prescription Wniting BY PIERRE A. FISH, D.Sc., D.V.M. Professor of Veterinary Physiology and Pharmacology, New York State Veterinary College, Cornell University, Ithaca, N. Y. A full list of drugs with their doses for the different domestic animals. Therapeutic terms and a list of terminations of medical terms applicable to Veterinary medicine. Prescription writing is discussed in some detail, with illustrative prescriptions. Thermometric equivalents. Weights and measures. Latin words and phrases used in prescription writing. Incom- patability. Poisons and their antidotes. Classification of medicines according to their physiologic action. Pages for selected prescriptions. Red Leather Flexible Covers, 160 pages. Third Revised and En- larged Edition $1.50 net Postpaid. * * A small volume which will be of indispensable value to practitioners and students. * 7 It will return the investment with interest every other day. — American Veterinary Review. Examination of the Urine of the Horse and Man BY PIERRE A. FISH, D.Sc., D.V.M. Simple directions are given for performing the tests necessary to de- termine the normal or abnormal conditions of the urine. Price, $1.50 net Postpaid. TAYLOR & CARPENTER _ VETERINARY PUBLISHERS AND BOOKSELLERS ITHACA, N. Y. Digitized by Microsoft® Exercises in Physiology BY PIERRE A. FISH, DSc. D.V.M. A laboratory manual. Part I, Chemical Physiology. Part Il, Ex- perimental Physiology. Second Edition. Revised and Enlarged. $1.50 net Postpaid. The work is modern. Its directions are admirably concise and clear. It will aid teachers as well as students.—Jour. of Applied Microscopy and Laboratory Methods. Veterinary Medicine BY PROFESSOR JAMES LAW, F.R.C.VS. Director N. Y. S. Veterinary College, Ithaca, N. Y. VOL. |. General Pathology: Diseases of the Respiratory and Circu- latory Organs. pp. 566. 8vo. 2nd Ed. Revised and en- larged. Price $4.00. VOL. If. Diseases of Digestive Organs, Liver, Pancreas and Spleen. pp. 595. 8 vo. 2nd Ed. Revised and enlarged. Price $4.00. VOL. Ill. Diseases of Urinary and Generative Organs, Skin, Eye and Nervous System. pp. 611. 8 vo. 2nd Ed. Revised and enlarged. Price $4.00. VOL. IV. Infectious Diseases, Sanitary Science and Police. pp. 675: 8 vo. 2nd Ed. in Press. Price $4.00. VOL. V. Parasites and Parasitism. Ist Ed. pp. 532. 8 vo. Price $4.00. Destined to become a standard authority.—Am. Vet. Review. No better work of reference could be.— Veterinary Record. Of Professor Law's latest volume (IV), we can speak in terms of warm praise. With its companion volumes, will form a valuable addition to the literature of veterinary medicine.—Jour. of Comp. Path. and Thera. Published by the author. Sent, express prepaid, on receipt of price. TAYLOR & CARPENTER VETERINARY PUBLISHERS AND BOOKSELLERS ITHACA, N. Y. Digitized by Microsoft® Pure Milk and the Public Health Manual of Milk and Dairy Inspection by Archibald Robinson Ward, B.S.A., D.V.M., Assistant Professor of Bacteriology and Director of the State Hygienic Laboratory, University of Cali- fornia, Berkeley, California. With two chapters by Myer Edward Jaffa, M.S., Professor of Nutrition and Director of the State Food and Drug Laboratory, University of California. With seventeen illustrations. $2.00 net Postpaid. The Clinical Pathology of the Blood of Domesticated Animals BY SAMUEL HOWARD BURNETT, MS,., D.V.M. Instructor in Comparative Pathology and Bacteriology, New York State Veterinary College, Cornell University, Ithaca, N. Y. With four colored plates and twenty-four figures. $2.50 net Postpaid. TAYLOR & CARPENTER VETERINARY PUBLISHERS AND BOOKSELLERS ITHACA, N. Y. Digitized by Microsoft® © Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® pues caaciened a; ; : : ee ve Te Oe eS ee ey SOR Raa eK RL hee ARE Cee ENTE ERE ae Nhs tne kets a Nee ane Meats oh ohooh de acm iene ea : s see : aa = serach lates Pa eons Ut c