672 EXPERIMENT STATION RECORD. 



solids-not-fat, hence the richer milk has a gi-eater commercial value. Payment on 

 the basis of weight or volume alone is deemed unjust to the richer milks, because 

 the varying proportion of solids-not-fat in relation to fat is not taken into con- 

 sideration. When fat alone is used as a basis of payment the extra propor- 

 tional amount of solids-not-fat in poorer milks is not recognized, and milks 

 richer in fat get somewhat more than is due them for their skim milk solids or 

 solids-not-fat. 



It is concluded that a strictly accurate basis of payment doing full justice to 

 each milk according to its composition must consider both fat and skim milk 

 solids or solid.s-not-fat, allowing for each pound of solids-not-fat one-tenth the 

 amount allo\\ed for fat. The solids-not-fat must be determined in each case as 

 well as the fat. 



Problems of a rural milk supply. — The keeping quality of milk and its 

 transport, K. G. Allan and J. V. Takle {Ar/r. Jour. India, 10 (1915), A'o. 4? 

 pp. 829-3^2). — In connection with e:fperinients carried on at the college dairy 

 at Nagpur in the hot weather of 1915, it was found that the tendency to form 

 butter during transport varies with the temperature at which the milk is 

 transported, the degree of fullness of the milk container, the length of time 

 after milking at which transport is done, and the kind of milk transported. 

 Butter was found in all milks below 90° F., but more so in buffalo's than cow's 

 milk and in the milk of one individual more than in another. Pasteurization 

 has been found effective in reducing the tendency of transported milk to form 

 butter. 



The significance of bacteria in milk, L. A. Rogers (Cream, and Milk Plant 

 Mo., 4 (1915), Xo. 4, pp. 15-lS). — In this paper, which was presented at the 

 fourth annual convention of the International Association of Dairy and Milk 

 Inspectors, at Washington, D. C, in October, 1915, as previously notetl (E. S. R., 

 33, p. 705), the author shows wherein the bacteriological examination of milk 

 is not an entirely reliable test of the sanitary condition of milk. This is be- 

 cause of the inaccuracies that enter into the examination, the lack of definite 

 knowledge concerning tlie habitat of certain bacterial groups, and the unknown 

 factor of bacterial multiplication. How much of a high count is due to origi- 

 nal contamination and how much to multiplication is deemed uncertain. It is 

 suggested that it may be necessarj' to distinguish between measures to reduce 

 the bacterial count and measures in the interest of decency and cleanliness. 



Bacteriology of cream ripening, K. Peiser (.1/i7A' Dealer, 5 (1916), No. 4f 

 pp. 26, 27). — Data on the bacterial count of cream during the various stages 

 of ripening and churning, and including butter in storage, are given. 



A large part of the bacteria present in ripened cream is removed after churn- 

 ing from the butter with the buttermilk. Many more are washed out of the 

 butter by the washing that occurs during the working of It. The more impure 

 the cream the greater is the importance of getting the butter thoroughly washed, 

 since a great percentage of the bacteria is removed in this way. It has been 

 shown that the bacterial content of water used for washing of the butter has 

 an influence on the keeping quality. Butter as a finished product contains a 

 little more than one-tenth as many organisms as ripened cream does. In but- 

 ter the salt and low temperature have a deleterious effect on the starter type 

 and as a result they die off rapidly at first, then more gradually, until after some 

 time In storage the ratio of their numbers compared with the numbers of other 

 types is very much reduced. 



Determination of the theoretical butter overrun, P. Rinckleben (ilolk. 

 Ztg. [Hildesheim], 29 (1915), Xo. 82, pp. 1029, i05O) .—Formulas are given for 

 estimating the probable overrun in butter. 



