FROM THE PRACTICAL VIEWPOINT 



qualities of the milk are not impaired, but are 

 rather improved. 



It is, however, found necessary to heat the milk 

 to about 130 before subjecting it to the electric 

 current, and during electric treatment it attains a 

 temperature of about 158, due to the resistance 

 of the milk to the electric discharge. It is an 

 open question whether the destruction of bacterial 

 life, which undoubtedly takes place, is due to the 

 electric current or to the heat to which the milk is 

 subjected. The results of tests made of the milk 

 so treated indicate that the percentage of bacteria 

 destroyed is high. If the effectiveness of the appa- 

 ratus depends upon the heat generated during the 

 process, it is probable the high percentage of bac- 

 terial destruction is partially due to the fact that 

 milk flows in such a small stream through the ma- 

 chine. Every portion of it is thus uniformly 

 heated to the maximum temperature, and even 

 when milk is not held for any appreciable length 

 of time, it has been found in laboratory tests that 

 the bacteria are killed. As before stated, it is a 

 fact that mechanical defects which exist in all ma- 

 chinery render it difficult to maintain uniform tem- 

 peratures. This makes the holding of hot milk a 



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