THE PASTEURIZATION OF MILK 



the cream line than is ordinarily appreciated. It 

 lias been stated to the writer, that in one instance 

 where the cream line was materially reduced dur- 

 ing the pasteurization process, the experiment was 

 made of reducing^the speed of the agitator which 

 kept the hot milk in motion. After the speed had 

 been so reduced it was found that the cream line 

 upon the milk resumed its normal character. 



It will also be noted from the foregoing descrip- 

 tion of the various methods of handling milk that 

 in those plants where there was most agitation of 

 the milk, and especially where the pumping of 

 hot milk was practiced, the most difficulty with the 

 cream line was experienced. There are possibly 

 other factors which affect the cream line, among 

 which may be: 



1st, the age of the milk before pasteurization. 



2nd, the grade of cows from which the milk was 

 produced. 



3rd, the fact that milk has or has not been frozen 

 before being treated. 



The tests made proved that it is entirely pos- 

 sible, under the most favorable conditions, to heat 

 milk to 145 and hold it for thirty minutes without 

 producing any injurious effect upon the cream line. 

 228 



