BUTTER. 109 



DISCUSSION OF RESULTS. 



The results of the three experiments presented in the above 

 table indicate, without question, that the food of a cow does, to 

 some extent, vary the composition of the fat of her milk and 

 thereby influences the texture of her butter. 



The work of Morse and others led the writer to assume that 

 the fat or oil of some of the so-called concentrated feeds was the 

 disturbing element, consequently these experiments were planned 

 and carried out particularly to test that phase of the subject, and 

 the evidence here presented seems to support the assumption. 



It will be noticed that in making up the daily rations an effort 

 was made to make the digestible protein for each period as nearly 

 the same as possible, the chief variations of the rations being in 

 the fat content of the grain fed. 



Before referring to the table, it is necessary to state that we 

 did not find the melting point of the fat as determined by the 

 oflficial method, a true indication of the hardness of the butter. 

 It is true that the fats of very hard butters have high melting 

 points, but the fat of some of the medium hard butters gave 

 melting points practically the same as the softest butters, con- 

 sequently, for convenience in discussing the results, an arbitrary 

 scale of hardness is used, 10 representing the hardest and 6 the 

 softest butter. 



Several attempts were made to find some reliable way of 

 determining the hardness or stability of butter in the laboratory 

 that could be compared with its hardness as determined com- 

 mercially. Some mechanical means have been recommended 

 such as dropping a weighted glass rod and measuring the degree 

 of penetration in the different butters at the same temperature. 

 This method appears to better show the density or compactness 

 of butter than its ability to stand up at high temperatures. In 

 our trials of it, different prints of the same lot showed as great 

 variations as the different lots. It is impossible for a butter 

 maker to handle butter so nicely as to give it the same degree 

 of compactness each time. 



Several methods of determining melting points of the fat were 

 tried but none appeared to be more satisfactory than the official 

 method which was used and no singfle laboratorv test indicated 



