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EVAPORATED MILK HOMOGENIZING 



Tig. 50. The Viscolizer 



Courtesy of John W. Ladd Co. 



The Viscolizer. This homogenizer is equipped with a cone- 

 shaped resistance valve of "Viscolite" metal, through which the 

 milk is forced. The 

 conical valve has an 

 accurately fitted 

 guide in the valve 

 seat, for the purpose 

 of lifting squarely 

 from the seat and 

 providing an open- 

 ing of equal dimen- 

 sions for the entire 

 circumference. This 

 valve is regulated by 

 a differential screw 

 mechanism in which 

 the travel or advance 

 of this screw is reduced 28 times from its normal pitch, making 

 possible a very fine adjustment. One complete turn of the 

 handwheel opens or closes the valve approximately to .001 of 

 an inch. The milk is forc- 

 ed through this valve by 

 a triple pressure pump. 



Operation of the Ho- 

 mogenizer. In order to 

 avoid fat separation it is 

 necessary to subject the, 

 milk to enough pressure 

 to reduce the fat globules 

 to at least one-third their 

 original size. If enough 

 pressure is applied to di- 

 vide the fat globules into 

 much smaller units there 

 is a tendency to also 

 change the properties of 



the casein tO SUch an ex- Courtesy of Union Steam Pump Co. 



tent as to cause it to give rise to copious precipitation, when the 

 evaporated milk is sterilized, and making the finished product 



Fig-. 51. Atomizing- valve and differential 

 screw mechanism of Viscolizer 



