l68 PROTECTION OF THE CONSUMER. 



The milk to be pasteurized is placed in the bottles, the 

 bottles placed in the vessel and the vessel filled with boiling 

 water and set aside at once to cool. The practical result is 

 that the milk is heated to the proper temperature. After 

 about half an hour cold water is run into the vessel to cool 

 the milk as in Fig. 24, B. Such a plan of pasteurization is 

 not strictly accurate, but is satisfactory for practical pur- 

 poses. It is also possible, by an even simpler device, to 

 accomplish the same purpose with less accuracy. If the milk 

 is placed in quart bottles and these placed in a pail which is 

 filled with boiling water and set aside to cool, the result is 

 that the milk is warmed to about the proper temperature by 

 the .time that the water is cooled to the same temperature. If 

 allowed to stand in this pail for half an hour and then subse- 

 quently taken out and cooled, the milk is practically pas- 

 teurized, although the method of course is by no means 

 accurate. It has the advantage, however, of being within the 

 easy reach of any common household, and probably accom- 

 plishes the purpose about as well as more expensive methods 

 of pasteurizing. 



Utility of Pasteurization in the Dairy. Pasteurization 

 has a utility in the dairy quite apart from its rendering the 

 milk more wholesome. It is a device frequently adopted 

 for the purpose of getting rid of the ordinary milk bacteria 

 which .would be liable to produce trouble. In butter-making, 

 as will be noticed later, pasteurization is very widely adopted 

 for destroying the bacteria in cream in order to make the 

 cream free for the inoculation with other desirable bacteria. 

 In the somewhat recently developed industry in this country, 

 of supplying cream in large quantities for city custom, the 

 process of pasteurization has been found of great use. The 

 cream must sometimes be shipped for long distances and 

 may be three or four days old before it is consumed. In 

 preserving it this length of time and thus enabling it to com- 

 mand a market, pasteurization has been of great service, and 



