j 6 ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 



other milk constituents. Milk fat being relatively lighter or lower in 

 specific gravity than water increased by the other milk solids, would nat- 

 urally rise, and anything which tends to increase the difference in spe- 

 cific gravity aids creaming. Milk containing large fat globules will cream 

 more rapidly and completely than milk with small globules, because the 

 volume of the globules compared .o surface is much greater than that of 

 the small, thereby reducing the friction of the fat rising through the 

 milk, and lessening the surface tension, both of which acts similarly to 

 that of an increase of specific gravity. The fat in the skim milk is made- 

 up very largely of small globules which fail to separate or raise ?s soon 

 as the others. For this feason, milk creams more thoroughly from cer- 

 tain breeds of cows, or more likely from certain individual cows. The 

 Jerseys and the Guernseys are generally considered to have the larger 

 fat globules, therefore the cream rises more easily from Jersey or Guernsey 

 milk. However, this is not always true. It depends entirely upon the 

 individual cow. We have some Short Horns where the cream rises 

 equally as well, and has equally as large fat globules. We hear of the 

 iron-clad' rule that the Jerseys have the largest, and the Holsteins the 

 smallest, but it all depends upon the individual animal. 



The shallow aud the deep setting systems are familiar to all, and 

 probably need no explanation as to the method of procedure. We take 

 it for granted that at the present day every dairynran accepts the fact that 

 the deep setting system is far more efficient than the shallow setting 

 system, and the efficiency is decidedly increased by a temperature of about 

 100 degrees to begin with in milk, and then suddenly immersed in ice 

 water. This will naturally lower the temperature and make the water 

 or the serum specifically heavier. Besides, the cooling of the outer layer 

 of the milk will increase the density, causing it to fall and displace the 

 warm milk, thereby creating a current which seems to greatly facilitate 

 the separating of the cream in the deep setting system. 



The so-called dilution or hydraulic method of cream separation is 

 comparatively an old process of raising cream. The process has fallen 



