ON MILK AND MILK-TESTING 69 



How may the per cent of total solids be deter- 

 mined? 

 By adding the fat as determined by the Babcock 

 test to the solids not fat, as determined by the 

 application of the formula. 



Is there a formula for determining the per cent of 

 protein in milk? 

 The following formula has been developed by 

 G. A. Olsen: 



TS- A 



P 



3.694 



In this formula T S=total solids, A=ash, and 

 P=protein. The ash is to be called .75 in all 

 cases. 



Below what percentage do the solids not fat of 

 pure milk rarely go? 

 The solids not fat of pure milk are usually more 

 than 8.5 per cent, and they very rarely go below 

 8.4 per cent. 



How does the addition of water to milk affect the 

 specific gravity? 



Since the specific gravity of water is less than the 

 specific gravity of milk, the addition of water to 

 milk reduces the specific gravity of the mixture. 



How does the skimming of milk affect its specific 

 gravity? 



Since the specific gravity of the fat is less than 

 the specific gravity of the other constituents of 

 milk, skimming increases the specific gravity. 



