TESTING OF MILK AND CREAM 101 



pipette and measuring off 9 c.c. of cream. This is 

 then run into the cream-test bottle. As some of 

 the cream will stick in the pipette we wash this 

 loose by drawing up a little clean hot water into the 

 pipette up to the 9 c.c. mark and run this washing 

 into the test bottle with the cream already there. 

 We now measure out 17-5 c.c. of sulphuric acid and 

 add slowly in same manner as for milk. Rotate 

 slowly until all cream is dissolved and darkened in 

 colour, proceeding with the test in the same manner 

 as for the milk test. In reading the cream test the 

 result is multiplied by two : Thus, if the result 

 shows 25 divisions of fat in a 3<D-division bottle, the 

 test is 25 x 2 = 50 per cent, butter fat. 



Butter v. Butter Fat. 



This means that in 100 Ibs. of cream with above 

 test there are 50 Ibs. of pure butter fat ; but if the 

 farmer churns this 100 Ibs. of cream he would get 

 on an average 60 Ibs. of butter suitable for market. 

 This difference of market butter over the butter fat 

 test is known as the "over-run." In this case the 

 lo-lb. difference is made up of i Ibs. salt, J Ib. 

 curdy matter, 8 Ibs. of water. A farmer should not 

 be misled by comparing the results from a private 

 churning with the test of the same cream as given 

 by the nearest butter factory, for the average 

 creamery only pays the farmer for the amount of 

 pure butter fat in his cream, and not for the amount 

 of butter which said cream might make. 



