CREAMING 59 



Hand separators first appeared on the market in 1886. 

 They are extensively used on dairy farms at the present 

 time and are rapidly replacing the gravity methods of 

 creaming. 



In 1887 a machine appeared on the market which ex- 

 tracted the butter directly from sweet milk. This machine 

 was called butter extractor.* The butter made with 

 the extractor was inferior in quality and the machine 

 has practically gone out of existence. 



Choice of Separator. In choosing a cream separator 

 we should be guided by three things: i. Efficiency of 

 skimming ; 2. Power required to operate ; 3. Its durability. 



I. EFFICIENCY OF SKIMMING. 



Under favorable conditions a separator should not leave 

 more than .05% fat in the skim-milk by the Babcock test. 

 There are a number of conditions that affect the efficiency 

 of skimming and these must be duly considered in making 

 a separator test. The following are some of these con- 

 ditions : 



A. Speed of bowl. ' 



B. Steadiness of motion. 



C. Temperature of milk. 



D. Manner of heating milk. 



E. Amount of milk skimmed per hour. 



F. Acidity of milk. 



G. Viscosity of milk. 

 H. Richness of cream. 



I. Stage of lactation. (Stripper's milk.) 



A. The greater the speed the more efficient the cream- 

 ing, other conditions the same. It is important to see 



