CHAPTER XXXIX 

 BACTERIA IN CREAM, AND CREAM-RIPENING 



THE numbers and kinds of bacteria found in cream 

 are determined to a great extent by the method of its 

 production. Cream secured by separating sweet milk 

 will differ bacteriologically from cream prepared by the 

 shallow or deep-setting systems, at low or at compara- 

 tively high temperatures. Separator cream made from 

 fresh milk, with a low bacterial content, will contain 

 frequently but a few thousands of bacteria per cubic 

 centimeter. For instance, one of the cream samples 

 at the milk and cream contest at Cleveland, in 1907, 

 contained only 1,100 bacteria per cubic centimeter, 

 while three others contained from 20,700 to 29,200 

 per cubic centimeter. In two samples, on the other 

 hand, the numbers were 392,000 and 402,500 per cubic 

 centimeter, respectively. These differences were un- 

 doubtedly due to the care observed in the production 

 of the milk and its subsequent treatment. It is generally 

 true that, everything else being equal, milk of good 

 keeping quality will furnish cream of good keeping 

 quality. In the production of good cream, therefore, 

 the same precautions as to cleanliness and temperature 

 should be observed as were already noted in the dis- 

 cussion of milk. 



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