122 BOARD OF AGRICULTURE. 



ing the milk among the embers of a low fire ; but we preferred 

 water as the heating medium. She judged of the due degree of 

 heat merely by dipping her finger in the milk, and by the wrinkling 

 of its surface ; and we found that the heat considered by her 

 suflScient generall}" ranged from 135° to 156°, and was occasionally 

 as high as 160° or 162° Fahr. The milk was drawn from below 

 the cream by a syphon ; and the latter was placed in the milk 

 house until the following day, when it was churned. The butter 

 weighed, when washed and well worked, 1998 grains. It had a 

 rich yellow color, tasted agreeably, and was quite free from the 

 peculiar scalded flavor of the milk. 



I may here state that by churning the milk of No. 1 and No. 3 

 we could obtain a few more grains of butter, on some occasions ; 

 but we could never obtain the smallest quantity of butter from the 

 milk of No. 5, so completely does the scalding process separate 

 the buttery matter from the milk." 



These and similar experiments were confirmed by many trials, 

 and the general result was that the largest quantity of butter is 

 produced by the Devonshire method ; the next in quantity by 

 churning the milk and cream together when they have become 

 slightly acid ; the third in quantity is afi"orded by cream kept iintil 

 it is slightly sour ; the smallest quantity is obtained from sweet 

 cream. 



In order to decide on the keeping qualities of the butter obtained 

 by the four processes above detailed, samples were exposed to the 

 free action of the atmosphere. No. 1 was found to remain longer 

 without any rancid taste than the other kinds. Nos. 3 and 4 were 

 nearly on an equality in this respect; if there was any difterence it 

 was in favor of No. 3. No. 5 became rancid more quickly than 

 No. 3 or No. 4. When salted for keeping, and then spread on 

 glass plates and exposed to the air, rancidity appeared in about 

 the same order; commencing first in No. 5, or the butter from 

 clouted cream ; next in No. 4, then in No. 3, and lastly in No. 1. 

 The rancidity was supposed to arise from varying proportions of 

 casein ; and on instituting a series of experiments to ascertain the 

 fact, it was found that casein existed in smaller proportions accord- 

 ing to the power of the butter to preserve its freshness. 



In October experiments were made which proved that over- 

 churning — that is, continuing the process after the full separation 

 of the butter — was very injurious to the quality of the butter, 

 although it increased its weight. 



