l86 MANAGEMENT OF DAIRY PLANTS 



The amount of fat lost in the buttermilk is readily determined, 

 as the weight of the cream churned is a known quantity and the 

 weight of the butter obtained is also known. The weight of the 

 buttermilk in which the loss occurs is the difference between the 

 weight of the cream churned and the weight of unsalted butter 

 obtained. 



Example. Determine the amount of butter fat lost in the 

 buttermilk from churning 2,000 pounds of cream when 700 

 pounds of butter containing 3 per cent of salt is obtained, and 

 the buttermilk contains .2 per cent of fat. 



Answer: (2,000 700 X .97) .002 = 2.642 pounds. 



A formula similar to that used for determining fat loss in 

 skim milk is also applicable in this connection. The following 

 formula may be used when unsalted butter is concerned: 

 c(F^ Pl ) 

 F-f 



In the foregoing b is to represent pounds of buttermilk ob- 

 tained, f, per cent of fat in the buttermilk, and F, the per cent 

 of fat in the butter. These factors are not absolutely correct in 

 practical applications, as the water used for washing the butter 

 may have a slight influence on the moisture content of the but- 

 ter; however, not to such an extent that it will be of importance 

 for the creamery manager to consider. 



It will be noticed from Table XIII that the loss of .1 per cent 

 of fat in the buttermilk reduces the overrun .2 per cent when the 

 fat content of cream used is 35 per cent and of the butter manu- 

 factured 80 per cent. This factor decreases slightly as the fat 

 content of the butter increases and it increases as the fat con- 

 tent of the cream decreases (Table XIV). 



Miscellaneous Manufacturing Losses. Such losses occur 

 in transferring cream from the receiving cans to vats, from 

 vats to churns, and in handling cream or butter. They should 

 not normally exceed .2 of one per cent of butter fat received. In 

 accordance with Minnesota experiments l about one-half 

 of one per cent of the total fat received was lost in vats, pipes, 



1 Bulletin 177, Minnesota Ex. St., 1918. 



