238 



THE BOOK OF BUTTER 



be sampled for testing, since such sample will not be repre- 

 sentative. It is said that such milk should be melted and 

 carefully remixed before any is taken for a test, but in melt- 

 ing the ice a temperature of not over 85° F. should be em- 

 ployed. Too high temperature is likely to melt the fat and 

 cause a separation in the form of an oil. When this hap- 

 pens, it is almost impossible to remix it evenly with the milk. 

 If milk is allowed to stand several hours before freezing, 

 the fat will rise to the surface and form a cream line. If 

 this line freezes, the ice will be rich in fat. If the milk is 

 agitated while freezing, the ice formed will be low in fat, 

 since freezing tends to squeeze the fat out of the ice. Thus 

 the liquid portion contains a greater proportion of fat than 

 the ice. If the creamery-man samples frozen milk, he is 

 likely to pay for more fat than he actually receives. In the 

 following table, Ross and Mclnerney ' compare the percent- 

 ages of fat found in samples of partly frozen whole milk : 



Table 



XXVIII — Percentage of Pat Pound in Milk in 

 Various Conditions as to Preezing 



' Ross, H. E., and Mclnerney, T. J., The Baboock Test, etc., 

 Cproell UBJy. Agri. Exp. Sta., Bui. 337, p. 35, 1913. 



