il2 



KvAPORy\'il'D RIiLK — HOMOGENIZING 



\'ided \ery minutely. This t3pe of honiof^enizer has not lieen 

 used niucli as yet in the manufacture of evaporated milk and 

 Ijut little is known concerning;- its effect on this product. 



In the Progress homogenizer the homi^genizing principle 

 consists of forcing the milk, hv means cjf single acting pumps, 

 between a scries of discs with ground surfaces. The discs lay 

 flat one uijon the other, tliey are enclosed in a cylinder and are 



Fig. 39. The Gaulin homogenizer 



Courtesy of Creamery Package Mfg. Company 



held in place by a rod running through their center. The discs 

 are pressed against each other by a heavy spiral screw, which 

 regulates the pressure to \^'hich the milk is subjected. The milk 

 passes from the center to the periphery of the discs. While being 

 forced through the discs the fat globules are split up very finely. 

 The discs used in this machine arc of two types. One type has 

 \-erv line irregular groo\'es. The milk shoots through these 

 grooxes against hard shoulders. Tlie other type of discs has 

 smooth surfaces but their area of contact is narrow. Ihe milk 

 passes through between these smooth surfaces, 



