PASTEURIZED M 



279 



fact that in consequence of the strong and rapid heating of the nitro- 

 genous matter, the milk forms a firm crust on the hot surface. This has 

 to be prevented by special arrangements of the best possible kind. The 

 second disadvantage consists in the fact that the apparatus works con- 

 tinuously, and that the only thing taken into account is to bring the milk 



Milk 





Fig. 80. Pasteurizing Apparatus (Lefeldt). 



quickly to a certain high temperature, and as soon as this temperature 

 is reached, to allow it to flow away. In order to increase the capacity of 

 the machine per hour, what is aimed at is to shorten as much as possible 

 the period of the action of the temperature on the milk, and to raise the 

 final temperature as high as possible. Since no apparatus among those 

 above described may be said to yield with certainty properly Pasteurized 

 milk, not one of them can be described as effecting what they ought to 



