THE PASTEURIZATION OF MILK 



again raise the temperature to the desired point. 

 The increased amount of heating and cooling sur- 

 faces required for this form of pasteurizing ma- 

 chine calls for careful cleaning and sterilization. 



Automatic Recorders 



The automatic recording of the milk temperature 

 is desirable, and in most cities where the pas- 

 teurization of milk is subject to public control it 

 is required. The milk company which is really 

 anxious to put out a safe product wants an office 

 record which will indicate whether the work is 

 being properly performed. With health authori- 

 ties, such a record is necessary, since it is impos- 

 sible for inspectors to be at pasteurizing plants all 

 of the time to watch their operations. A correct 

 automatically made record is the best substitute 

 for personal inspection. To be of ideal value, such 

 a record should show, not only the temperature, but 

 also the time of holding. When the tank or batch 

 heater is used, the single recorder attached to the 

 tank will show these items with fair accuracy, but 

 the observer must note whether or not the cooling 

 is either wholly or partially done in the tank itself. 

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