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DAIRY TECHNOLOGY! 



The greater the degree of heat, and the longer the ex- 

 posure, the more intense is the action on the condensed 

 milk, and, therefore, the harder the coagulum formed. 

 Since absolute sterility of the milk is necessary, and since 

 heat is the only agent that can be used to bring this con- 

 dition about, the milk must be exposed to such degree of 

 heat, and such duration of that heat as will accomplish 

 complete sterilization. 



Shaking the Canned Milk. The condensed milk hav- 

 ing been sterilized in sealed cans, the next process in order 



FIG. 48. Combined machine for sterilizing and shaking condensed milk. 



is the shaking of the cans to break any lumps of curd or 

 fat that may have formed, and to insure a smooth, homo- 

 geneous mixing of the fat. The shaking machine may be 

 combined with the sterilizer or it may be a separate piece 

 of apparatus. 



After the shaking process, the cans are placed in the 

 testing room, or incubator, as it might be called, where 

 they are kept at about blood heat for several days. If 

 any live spores are present in the milk, they will germinate 



