528 



STATE BOARD OF AGRICULTURE. 



Lot (dairy milk.) 



One. 



Number of germs introduced per c. cm i 240 



Time of testing acidity | 72 hrs. 



Acidity I 62° 



Time of curding 55 hrs. 



Temperature maintained 23° 



Count of germs per 1-1000000 c. cm 112 



Two. 



249 

 72 l.rs. 



(iO° 

 55 hrs. 



23° 



113 



Three. 



249 



72 hrs. 



62° 

 55 hrs. 



23° 



111 



Four. 



249 

 72 hrs, 



(12° 

 55 lira. 



23° 



112 



The flask cultures moved along together in their development without any 

 appreciable difference in appearance. They were as one flask. 



Comparing such uniform results as obtained in the table just outlined with 

 what has gone before and with what will follow as additional evidence, it fol- 

 lows that care must be exercised if constant interpretations are sought, and if 

 dependence is to be placed upon milk cultural work from the bacteriological stand- 

 point. Generally mixed milks are employed and these are more likely to be 

 uniform than milk from individual cows. 



Richmond* gives a table of analyses of milk from different breeds: 



Breed. 



Ayrshire. . 

 Guernsey. 

 Holstein.. 



Jersey 



Shorthorn 



Total 

 solids. 



12.70 

 14.48 

 12.12 

 14.34 

 12.45 



Fat. 



3.68 

 5.02 

 3.51 



4.78 

 3.65 



Milk 

 sugar. 



4.84 

 4.80 

 4.69 

 4.85 

 4.80 



Protcids. 



3.48 

 3.92 

 3.28 

 3.96 

 3.27 



Ash. 



.75 



.64 

 .75 



.7a 



He also illustrates the variation in milk from the same cow in another table.f 



Little attention is usually paid to the acidity of milk, *, -, ^ *, although it 

 has long been known that it is subject to great variation, because of its more 

 or less indefiniteness; but in our bacteriological work it is possible that it plays 

 an important role as possessing functions of its own or standing for a measure- 

 ment of milk constituents, consequently some tests of our own determinations 

 are added to illustrate recorded knowledge which is not usually free of access. 



♦Richmond's "Dairy Chemistrj-," p. 125. 

 tRichmond's "Dairy Chcmistrv'," p. 124. 



1. See the work of P. Dornic, Revue Generale du Lait, 1 re, Annce No. 10, p. 217. 



2. Note: — Milk is alkaline or amphoteric to litmus and acid to phenol-plithalcin. Hoppe-Seylcr — Thierfelder. Phj'siologiscb 

 and^Pathologisch-Chemischc .\nalyse (1903), S. 537. 



3. "Milk lias always, when fresh, an amphoteric reaction: i. e.., it turns blue litmus paper slightly red and turmeric paper 

 slightly brown. \ similar reaction is posscssod by certain phosphate solutions, and it is probably to the presence of such in 

 milk that this reaction is due. Much has been written on this subject, but it is a point which more properly belongs to the 

 cheroistr>' of litmu.s and turmeric than to the chemistry of milk. This re.iction lias rciiuircd a false importance owing to the 

 erroneous idea that neutrality as measured by the action of litmus is cliemical neutrality; with the recognition of the fallacy of 

 this idea, the importance of tlic amphoteric reaction vanishes." Richmond — Dairy Chcmiiitrv' (1890), p. 8. 



4. K. Storch, in "Tierarztliches Zentralblatt" Wicn, 32, 1004, also 'Revue Generale du Lait," 4o, .'\nnce, No. 0, says that 

 the chemical reaction of milk is independent of food and that it is produced by the presence of acid and neutral phosphates 

 which do not neutralize each other. Only when the acids of fermentation are produced, the neutral salts arc transformed into 

 acid salts and the reaction of the milk becomes acid. The milk is amphoteric when the relation of the acid and neutral salts 

 is aatisfactor}', otherwise it is alkaline or acid. 



