146 HEATING MILK PREVIOUS TO SKIMMING 



low temperature was fixed owing to the supposedly bad effect 

 high skimming temperatures had upon the body of the finished 

 butter. Exposing milk at high temperatures to the centrifugal 

 force in a separator was said to produce a greasy body in butter. 

 According to experiments conducted at the Iowa Experiment 

 Station by the authors, milk can be skimmed at 175 F. without 

 any injury to the quality of the butter, providing the cream 

 is cooled to ripening temperature, or below, as soon as it has 

 been skimmed. After the ripening has been completed the 

 cream should be exposed at least three hours to a low tempera- 

 ture (50 F.) previous to churning. 



If the milk is heated in any of the best modern heaters, there 

 will be no injurious results to the quality of the butter. Pro- 

 fessor Dean, at the Ontario Agricultural College, has also found 

 it practical to heat to pasteurization temperature previous to 

 skimming. In many creameries in Denmark this method of 

 heating milk is also followed. The Danes, as a rule, however, 

 pass the heated milk over a cooler before it goes into the sep- 

 arator. 



The chief difficulty encountered by the authors in heating 

 milk to such a high temperature previous to skimming was 

 that the upper bearing in the separator got so hot that it was 

 deemed injurious to the separator, although the bearing did 

 not heat to such an extent as to cause the running of the machine 

 to be abnormal in any way. 



Advantages of Warming Milk to High Temperature Previous 

 to Skimming. The advantages of heating milk to a high tem- 

 perature (175 F.) previous to skimming may be summarized as 

 follows : 



(1) Undesirable taints are eliminated from the milk to a 

 greater extent than can be accomplished in any other way, 

 without applying chemicals. 



(2) The heating of whole milk destroys the germs in the 

 resultant skim-milk and cream practically as efficiently as when 

 they are heated after the skimming process has been completed. 



(3) Less heating and cooling apparatus is necessary. 



(4) Closer skimming is possible. 



