10 SELLING MILK 



taining 4 per cent butter fat, the dairyman ex- 

 pects to receive the full market price for milk 

 and a premium or extra price for butter fat equal 

 to the value of the I per cent excess which his 

 milk contains. 



Butter fat is measured best by the Babcock 

 test. Sulphuric acid added to milk makes the 

 separation of butter fat easy when the mixture 

 is whirled in a centrifugal machine. The sepa- 

 rated fat appears as yellow oil in the neck of 

 the glass bottle and the quantity can be easily 

 read from graduated marks on the neck. 



Fat tests may be made weekly or monthly. 

 Disputes often occur between farmers and dealers 

 regarding the fat tests. Changing cows changes 

 the amount of fat in the mixed milk of the dairy. 

 Removing cream from the top of the can for the 

 house makes a big difference in the fat test of the 

 the milk on that day. Where the farmer is 

 honest, and the dealer is honest, disputes can 

 always be settled by having the fat test made 

 in the presence of both parties. 



