62 CRLIAMHRY BUTTHR MAKING 



F. The higher the acidity of milk the poorer the 

 creaming. With sour milk the loss of fat in the skim- 

 milk becomes very great. This emphasizes the importance 

 of having the milk delivered to the creamery in a sweet 

 condition. 



G. Sometimes large numbers of undesirable (slimy) 

 bacteria find entrance into milk and materially increase its 

 viscosity. This results in very unsatisfactory creaming. 

 Low temperatures also increase the viscosity of milk 

 which accounts for the poor skimming at these tempera- 

 tures. 



H. Most of the standard makes of separators will do 

 satisfactory work when delivering cream of a richness of 

 $0%: A richer cream is liable to result in a richer skim- 

 milk. The reason for this is that in rich cream the 

 skim-milk is taken close to the cream line where the skim- 

 milk is richest. 



I. Owing to the very small size of the fat globules 

 in stripper's milk, such milk is more difficult to cream 

 than that produced in the early period of lactation. 



2. POWER REQUIRED TO OPERATE. 



This is a matter of importance as a heavy running 

 machine will add much to the running expenses of the 

 creamery. Such a machine will not only require more 

 fuel but will increase the wear of belts and machinery. 



3. DURABILITY. 



Cream separators are expensive machines and due re- 

 gard should be given to their wearing qualities. They 

 should be made of the best material, possess good work- 

 manship, and have as few wearable parts as possible. 



