530 



Bulletin 281. 



Table I gives a comparison of the results from the four tests just 

 described. 



Table I.— Results from the Various Methods of Determining Moisture, 

 Compared with the Gravimetric Test 



CORNELL BUTTER MOISTURE-TEST 



When butter is heated, a covering of casein will collect over the 

 surface of the sample. When the sample becomes quite hot, this cover- 

 ing is of snow-white color. After heating the sample for a time, the 

 foam begins to subside and loses its snow-white color, changing to a 

 dirty brown. By comparison with the chemical method, it was found 

 that when the foam had lost its snow-white color the sample had given 

 up all of its moisture. The appearance of the dirty-brown color was a 

 sure indication that all of the moisture had passed off, and if the sample 

 was not removed from the flame at th's point some of the butter would 

 volatilize. 



When butter is heated in a direct flame, it is difficult to drive off 

 all of the moisture and yet not volatilize some of the fat. In order 

 to obviate this serious difficulty, a thin sheet of asbestos was placed 

 between the flame and the container of the sample. The de- 



