QUESTIONS 



339 



will give the amount of the rich cream required for the mixture. 

 The difference between the amount of cream desired and the 

 amount of rich cream required will indicate the amount of skim 

 milk required to be mixed with the rich cream to produce the 

 desired result. 



Compositions, Ratios and Weights. — The richer any given 

 milk is in fat, the greater is the proportion of fat in the solids. 

 This fact is important to both producer and consumer. 



The richer milk or cream is the lighter it is per gallon. This 

 is because fat is only about 87 per cent as heavy as the skim milk 

 in which it is floating. The specific gravities and weights of the 

 gallon shown below are based on the temperature 68 degrees. F. 



QUESTIONS 



1. How does a separator separate? 



2. How much fat is lost in skim milk with gravity creaming? With mechan- 



ical creaming? 



3. What is the normal way of changing the fat content of cream? 



4. Explain reasons for fat variation in separator cream? 



5. How must a separator he set if it is to do good work? 



6. Explain on the board how to modify milk or cream to any given fat 



percentage ? 



7. What is the weight of a gallon of water, skim milk, milk, and 35 per 



cent cream? 



