VARIATION OF CREAM TESTS 



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heavier is thrown outward with a yet greater force. As the bowl 

 fills from the hopper above it naturally overflows, the skim milk 

 escapes from the openings that lead from the wall, and the fat, 

 mixed with enough milk serum to make it flow, escapes as cream 

 from an opening which leads from near the center of the bowl. 



To make a richer cream the normal way is to change the 

 relative positions of the two outlets, moving the cream screw 

 inward or, in some machines, moving the skim milk screws out- 



Fig. 112. — There are many makes of hand rream separators having value. This illustrates 

 a few of those used at the Minnesota School of Agriculture. 



ward. This makes the bowl carry more milk, increases the force, 

 that is, the squeeze, and results in a richer cream — and vice versa. 



" Why do cream tests vary so from the same machine ? " 

 This question has been asked and variously answered a great 

 many times but is still a live question. The following are the 

 chief causes of unintentional variation in the fat content of hand 

 separator cream as sent to market : 



1. Speed of the separator. — The faster the bowl revolves, 

 the richer the cream will be. Slow turning is one cause of thin 

 cream, though some makes of separators are more sensitive to 

 this influence than others. A woman or a child often is not 



