No. 6. DEPAKTMiSNT OF AGRICULTURE. 601 



Per cent, of Fat In Milk. 



Pounds of Butter that Should Be Made 

 from 100 Pounds of Milk. 



», ... 

 8.2,. 

 3.5,. 

 3.8,. 

 4.0,. 

 4.5,. 

 B.C. 



3.S7 pounds, or 3 pounds, ( ounces. 



3.63 pounds, or 3 pounds, 10 ounces. 



8.93 pounds, or 3 pounds, 15 ounces. 



4.27 pounds, or 3 pounds, 4 ounces. 



4.50 pounds, or 4 pounds, 8 ounces. 



5.06 pounds, or 5 pounds, 1 ounce. 



5.62 pounds, or 5 pounds, 10 ounces. 



44. How to Detect Losses by Yields of Butter. 



Ordinarily, one can detect losses of fat in skim-milk and butter- 

 milk by testing tliem for their fat content. In the absence of such 

 tests, one can make use of the above rule to ascertain how effective 

 one's work is in getting milk-fat into butter. For illustration, 

 suppose we make butter from milk containing 4 per cent, of fat, 

 and get 4 pounds and 3 ounces of butter. From the rule given above, 

 we should get not less than 4 pounds and 8 ounces of butter, so that 

 we have experienced a loss of 5 ounces of butter for 100 pounds of 

 milk. We have either lost extra amounts of fat or we have failed 

 to retain the usual amount of moisture in the butter or have experi- 

 enced losses in both of these directions. An experience of this kind 

 should move one to discern the causes of loss and then remedy them. 

 In case the amount of butter is greater than is called for by the 

 rule, then we have incorporated an extra large amount of water in 

 the butter. 



45. Milk-Fat as a Basis of Paying for Milk at Creameries. 



Until a dozen years ago, milk was very generally paid for by weight 

 alone at creameries. This method was based upon the belief that 

 it was milk that made butter and that all kinds of milk were of 

 equal value, pound for pound, in making butter. The next step 

 in the direction of progress was to pay according to the amount of 

 cream raised, measuring it by volume. This was a partial recogni- 

 tion that different milks varied in their butter-producing value. 

 The method of paying for cream was extremely faulty, because the 

 basis of payment was for so many spaces or inches of cream raised 

 in a can of certain depth and diameter. This method assumed that 

 all cream raised by the gravity system contained the same amount 

 of fat and was, therefore, of equal value for making butter. Investi- 

 gation showed that this assumption was wholly without foundation 

 and was extremely misleading. The next plan put into practice 

 was what was known as the "oil test," by which an attempt was 

 made to measure the butter-producing values of different creams 



