CHAPTER II. 

 SEPARATOR CREAM. 



THE centrifugal method rests on an entirely different 

 principle from those previously considered. The heavier 

 parts of the milk, the skim-milk, are whirled against 

 the circumference of a rapidly-rotating steel bowl, while 

 its lighter parts, the cream, remain nearer the centre. 

 The result is that not only is the cream separated from 

 the skim-milk, but all filthiness present in the milk is 

 also forced to the wall, where it forms a tough, sticky 

 layer, called "separator slime." The separation takes 

 place in the manner mentioned, both in the cream sepa- 

 rator and the extractor. 



By application of the separator method the cream may 

 be separated from the milk as soon as this comes to the 

 creamery. The time of infection is greatly shortened, the 

 chances of contamination of bacteria decreased, and the 

 bacteria already found in the milk do not get time to 

 develop. For these reasons this method possesses a de- 

 cided advantage over all other methods of cream separa- 

 tion known. 



At a large number of separator creameries in this and 

 other countries this point is not taken advantage of, how- 

 ever, as we often find that the milk, which is usually 

 warm when it comes to the creamery, is left for hours in 

 the hauling-cans, whereby of course its bacteria have an 



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