CHAPTER IV. 



TEMPERING AND SEPARATING. 



Tempering milk for separating is apparently 

 a very simple matter. At the same time there 

 is a right way and a wrong way of doing it. 



Sudden heating. Sudden heating is not ad- 

 visable, as milk so heated separates harder thcin 

 milk that has been gradually heated. This is 

 no theory. It is a hard fact that I discovered 

 in comparing the work of different creameries. 

 The theoretical part comes in when I try to 

 explain why this is a fact. This point devel- 

 oped as follows: In one of our creameries we 

 heated the milk for the separator with a jet 

 pump, which does its work very suddenly. In 

 another creamery the milk was heated mostly 

 in the receiving vat. By the use of the Bab- 

 cock test I found the most thorough skimming 

 was being done at the creamery where the milk 

 was heated in the large vat to near the proper 

 temperature and finished up in the channel 

 vat. The jet pump was in use in our home 

 creamery where I had the very best opportu- 

 nity to watch the work, but I could not secure 



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