HEATING MILK PREVIOUS TO SKIMMING. 119 
this country, and perhaps at the present time, is about 90° F. 
This comparatively low temperature was fixed owing to the 
supposedly bad effect high skimming temperature had upon 
the body of the finished butter. Exposing milk, at high tem- 
peratures, to the centrifugal force in a separator was said 
to producea greasy body in butter. According to some ex- 
periments conducted at the Iowa Experiment Station by the 
authors during the year 1902, 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 com- 
pleted the cream should be exposed at least three hours to a 
low temperature (50° F.) previous to churning. 
If the milk is heated in any of the best modern heaters, 
no injurious results to the quality of the butter will be obtained. 
Prof. Dean, at the Ontario Agricultural College, has also found 
it practical to heat to pasteurization tempcrature previous to 
skimming. In many creameries in Denmark this method of 
heating milk is also followed. The Danes, as a rule, however, 
have the heated milk pass over a cooler before it goes into 
the separator. 
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 Heat 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 skimmed milk and cream practically as efficiently 
