Preservation of Milk. 119 



Within the last few years this system has been quite 

 widely introduced into a number of cities, and the results 

 obtained are, on the whole, successful. As a system for 

 general use it does not meet with nearly as much opposition 

 as is offered to the use of the higher limits. 



One marked advantage accruing to this system is its 

 general applicability. Milk can be pasteurized where it is 

 produced under a single management as in the individual 

 dairy, or the product of several patrons can be treated to- 

 gether, as in a factory. The fresher and better the milk is, 

 though, the more suitable it is for pasteurizing. Therefore, 

 while it is possible to somewhat improve milk that has 

 been collected for some hours (12 to 24) if it is properly 

 pasteurized, still better results will be obtained if the treat- 

 ment is given nearer the animal. Under practical condi- 

 tions, however, pasteurizing near the place of consumption 

 has some advantages and is preferable, if it is possible to 

 transport the raw material quickly from the place of pro- 

 duction. 



For the preparation of high-grade milk supplies it may 

 be said that either the elimination of the bacteria by pas- 

 teurization, or preventing their gaining access to the milk, 

 as in sanitary dairies, is the most feasible and successful 

 way to deal with this question. 



Restoration of "body" of pasteurized cream. The ac- 

 tion of heat causes the tiny groupings of -fat globules in 

 normal milk (Fig. 22) to break up, and with this change, 

 which occurs in the neighborhood of 140 F., the consist- 

 ency of the liquid is diminished, notwithstanding the fact 

 that the fat-content remains unchanged. Babcock and 

 the writer * devised the following " cure " for this apparent 



1 Babcock and Russell, Bull. 54, Wis. Expt. Stat., also 13 Eept. Wis. Expt. Stat. 

 1896, p. 81. 



