PASTEURIZED MILK 77 



3. Pasteurized Milk Keeps Longer. Milk is com- 

 monly bought in quantities sufficiently large to supply the 

 consumer for 24 hours. During hot weather, even a good 

 quality of inspected milk may become unfit for use in 

 24 hours, unless a very low temperature is maintained. 

 Among the poorer classes and even among the middle 

 classes, ice is too expensive to use for. cooling purposes. 

 But because of the improved keeping qualities of pasteu- 

 rized milk, the consumer is able to keep this grade of milk 

 in a hygienic condition for a longer time than the regular, 

 inspected raw milk can be kept. 



Because of the prolonged keeping quality, the dealer 

 has fewer complaints from his customers, and he has 

 less loss through the souring of milk before it can be 

 delivered. Hence pasteurization is of economic import- 

 ance. 



Pasteurization of Milk Increasing. That pasteuriza- 

 tion is being adopted by more and more cities and dealers, 

 speaks strongly in favor of this grade of milk. In the year 

 1900, only 5 per cent of New York City's milk supply was 

 pasteurized; in 1909, 25 per cent was pasteurized, and 

 probably 33 per cent now undergoes heating. The city 

 board of health has ruled that after January i, 1912, all 

 milk, except that produced under certain conditions, shall 

 be pasteurized. In Boston 33 per cent of the milk is pas- 

 teurized; in Chicago 50 per cent, and in Milwaukee about 

 seventy-five per cent. 



Official Supervision of Pasteurization. H. C. Campbell 1 

 has shown that, in cities where milk pasteurization is not 

 under official supervision, commercial pasteurization can- 

 not be relied upon as a means of destroying pathogenic 

 bacteria in milk. 



1 U. S. Dept. of Agr., Bu. An. Ind., An. Kept., 1909. 



