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EXPLANATION OF EXERCISE XVIII 



The clarification of milk consists in removing from it the insoluble 

 dirt. The modern clarifier does this by means of centrifugal force. 

 The dirt found in milk is usually heavier than the milk itself and the 

 action of the centrifugal force deposits this dirt on the inside of the 

 bowl. Clarifiers work on much the same principle as do separators, 

 but each make of machine has special features tending to prevent 

 separation. Usually a clarifier runs slower than does a separator of 

 the same make and capacity. In a separator, the inner device is so 

 constructed as to spread the milk in a thin layer, thereby making it 

 possible to do more complete separation. 



In a clarifier the milk is not separated in as thin a layer and only 

 one outlet to the bowl is provided. 



The different construction of each machine will be studied when 

 the machine is used. 



EXERCISE XVIII 

 EFFECT OF TEMPERATURE ON CLARIFICATION 



1. Weigh out two cans of milk and thoroughly mix them by 

 pouring from one can to another until they are of uniform composi- 

 tion. 



2 . Clarify one can of milk at a temperature of 60 F. and clarify 

 the other at a temperature of 85 F. Note if there is any difference 

 in the kind and amount of sediment obtained. 



3. Stain some of the sediment obtained from each clarification 

 and make a drawing of the field. In case there is no microscopical 

 difference in the sediment only one drawing need be made. 



