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EXPERIMENTS CONCERNING THE FACTORS INFLUENCING THE 

 MOISTURE CONTENT <>F BUTTER. 



Accurate data concerning the moisture content of butter were meager, 

 and it seemed obvious that tins question could be satisfactorily settled 

 only by means of careful experiments. So, about two years ago, the Dairy 

 Department at Purdue University started investigations concerning the 

 variations of the moisture content of butter and the causes of these 

 variations. 



Analyses of butter of the Purdue Creamery and of about 30 creameries 

 in the State showed that in spring and early summer there was a rapid 

 and decided increase in the per cent of water in butter. Analyses of the 

 composition of the butter fats in the same butter showed a decided in- 

 crease in the per cent of volatile and soft fats (fats of a low melting 

 point) and a corresponding decrease in the per cent of hard fats in spring 

 and early summer. 



These results suggested the possibility that the composition of the 

 fats may, in a measure, control the per cent of moisture incorporated in 

 butter. On the strength of this assumption the pure butter fat was ex- 

 tracted from various lots of butter, and by means of fractional crystalliza- 

 tion at different temperatures the soft and the hard fats were separated 

 from one another as completely as was possible with this method. The 

 two classes of fats were then churned separately and under identical con- 

 ditions as to the moisture present and temperature. The analyses of these 

 churnings showed that the butter made from the soft fats contained about 

 50 per cent more water than the butter made from the hard fats. 



The uniformity of the results of repeated experiments justified the 

 conclusion that, other conditions being equal, the relation of soft to hard 

 fats controlled the moisture content of butter. 



EXPERIMENTS CONCERNING THE CAUSES OF VARIATIONS IN 

 THE PER CENT OF VOLATILE, SOFT AND HARD FATS. 



The results just described naturally lead to the question, What are 

 the causes underlying the variation in the proportion of soft and hard 

 fats? 



It is an established fact that certain feeds, when fed in excess, have 

 a tendency to produce an excess of soft or hard fats in butter. Thus, 

 for instance, cotton-seed meal, bran, corn, overripe fodders, etc., tend to 



