CREAM 56 



separator. In the gravity process, the milk is usu- 

 ally placed in shallow pans and allowed to remain in 

 a room at a temperature of about 60° for 24 or 36 

 hours, until the cream is separated by gravity. 

 When this process of creaming is followed the losses 

 of fat are usually greater than by any other method. 

 The losses are especially heavy when the cows are 

 well advanced in their period of lactation. While it is 

 possible to do reasonably effectual creaming by the 

 gravity process, the losses of fat are frequently ex- 

 cessive, amounting to from 25 to 30 per cent, and 

 more, of the total fat in the milk, the skim milk 

 often containing from .6 to 1 per cent of fat. 



In the cold deep scstting process the milk is set in 

 deep pails, which are immersed in water of a temj)er- 

 ature of 40° to 44° F. At tlie end of 12 hours 

 the process of creaming is completed and the skim 

 milk will usually contain from .2 to .4 of a per cent 

 fat. For the creaming of milk by the cold deep set- 

 ting process, it is necessary that the water in which 

 the milk is immersed be kept at a low temperature. 

 Tlie creaming commences immediately when the milk 

 is placed in the water. The milk in the bottom of the 

 can first becomes poorer in fat, then the middle layer 

 is affected, and finally the upper layer. The tem- 

 perature of the water at the time the milk is set is 

 of greater importance than the temperature of the 

 milk. A difference of 10° in the temperature of the 

 milk will not affect the efficiency of the creaming, 

 but a difference of 5° in the temperature of the 



