PASTEURIZATION 



133 



is not done, it cannot be regarded aw certain that the 

 milk has been freed from pathogenic micro-organisms. 

 ^Moreover, a pasteurizer which is to prepare milk for 

 use as food must fulfil the following requirements : 



1. The oitire qi(antit!j of milk, including the froth 

 formed during heating, must he heated equally to the 

 desired temperature. 



Fjord's pasteurizing apparatus. 



2. The apparatus must work reliahli/, in order that 

 thoi-e shall l>c no danger that at times the milk is not 

 sufficiently heated. 



'.K The miuhine must he cast/ to clean. 



