THE PASTEURIZATION OF MILK 



milk will be discharged until all the tubes have 

 become filled. 



In this form of holder, the flow of milk through 

 the apparatus is comparatively rapid. As before 

 stated, this rapid flow tends to prevent diffusion, 

 and the holding time more nearly approaches the 

 time required to fill the apparatus than in any 

 other form of flow-type holder. In some respects 

 it is rather difficult to make a satisfactory color 

 test upon this holder on account of the fact that 

 the air, which of course fills the holder when the 

 filling with milk is commenced, is not all forced 

 out as completely as is desired, and thus air pock- 

 ets are formed. It thus occurs that some milk is 

 forced from the discharge tube before the appara- 

 tus is completely filled. Thus it is difficult to ob- 

 tain the exact time required to fill the tubes. It 

 is claimed by the manufacturers that when it is 

 operating under the most favorable conditions the 

 milk will be held for 98 per cent, of the time re- 

 quired for the apparatus to become filled. The 

 tests observed by the writer indicate that the hold- 

 ing time is from 80 per cent, to 90 per cent, of the 

 filling time, which is a greater percentage than 

 with other holders. 



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