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CHAPTEE XII. 

 CALCULATION OF BUTTER AND CHEESE YIELD. 



A. CALCULATION OF YIELD OF BUTTER. 



212. Butter-fat test and yield of butter. The Babcock 

 test shows the amount of pure butter fat contained in a 

 sample of milk or other dairy products. The butter ob- 

 tained by churning cream or milk contains, in addition 

 to pure butter fat, a certain amount of water, salt and 

 curd. While an accurate milk test gives the total quan- 

 tity of butter fat found in the sample of milk or cream 

 tested, the churn cannot be depended upon either to 

 leave the same amount of butter fat in the butter milk or 

 to include the same amount of water, salt and curd in the 

 butter at each churning. 



If a quantity of milk, say 3,000 Ibs., be thoroughly 

 mixed in a vat, and then divided into half a dozen equal 

 portions, a Babcock test of the different lots will show 

 the same percentage of butter fat in each portion. If, on 

 the other hand, each of these lots be skimmed, and the 

 cream ripened in different vats and churned separately, 

 the same weight of butter from each lot of 500 Ibs. of 

 milk will not be obtained, even by the most expert but- 

 ter maker, or if all the operations of skimming, cream 

 ripening, churning, salting and butter- working were 

 made as nearly uniform as possible. Careful operators 



