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CHURNING 



Table 44. Effect of the Season of the Year on the Composition 

 of Butter Fat of Creamery Butter. 1 



of butterfat of butter made in the Purdue University Creamery 

 during the twelve months of the year. 



The above table shows that during the winter months 

 the melting point of the butterfat is highest, causing a relatively 

 firm butter while in summer it is lowest causing a soft butter. 

 The reason for the higher melting point in winter and the lower 

 melting point in summer is obviously largely due to the decrease 

 in winter and increase in summer, of the per cent of olein as 

 expressed by the Iodine number and of the volatile fatty acids 

 expressed by the Reichert Meissl number. The greater firmness 

 of the winter butter has been attributed by some writers to the 

 effect of the period of lactation. Since the majority of the cows 

 approach the end of their lactation period in winter it was as- 

 sumed that stripper cows produce fat with less olein, a higher 

 melting point and a higher degree of hardness than fresh cows. 

 This is erroneous and not substantiated by facts as shown in 

 below experimental results. In the experiment referred to in 

 table on next page the cows received the same feed ration 

 throughout the year. 



1 Hunziker, Mills and Spitzer, Moisture Control, Factors not under Control 

 of the Buttermaker, Purdue Bulletin 159, 1912. 



