PASTEURIZATION 



199 



enameled equipment, instead of copper-lined vats, would greatly 

 reduce the effect of agencies that make for butter deterioration. 

 As long as copper-lined pasteurizing vats are and must be used, 

 the danger of the injurious effect of the copper and its salts, on 

 the quality of cream and butter, may be materially minimized by 

 holding the cream in these vats for the shortest possible time 

 only, consistent with adequate chilling of the fat preparatory 



Pig". 33 Tig. 34 



Jensen circular vat pasteurizer with suspended coil 



Courtesy Jensen Cry. Mach. Co. 



to churning. The holding of cream in these vats over night can- 

 not be recommended. At certain seasons of the year it is al- 

 most sure to cause metallic and other off-flavors in butter. If 

 the cream cannot be churned the same day it is "dumped" and 

 pasteurized, it would be preferable, from the standpoint of 

 quality, to hold it over night in the cans set in the cooler. 



Construction of Covers. The construction of the covers of 

 these vats is also of great importance. The covers should be 

 lined with tinned copper on the under side and the lining should 

 lap over and up on the upper side of the cover so as to avoid 



