84 



VARIATION OF FAT IN MILK AND CREAM 



cent milk produces 40 per cent cream. Changes in the richness 

 of milk cause changes in the richness of the cream. Any condi- 



EFFECT OF RICHNESS OF MILK UPON THE CREAM 



100 LBS. OF 3$ MILK 

 CONTAINS 3 LBS. OF FAT 



,,,.. 



85 LBS. 

 SKIM-MILK 



TEST OF CREAM =20$ 

 - jx 100 = 20$ 



1OO LBS. OF 4.5# MILK 

 CONTAINS 4.5 LBS. OF FAT 



85 LBS. 

 SKIM-MILK 



15 LBS. OFCREAM = 3 LBS. OF FAT 15 LBS. OF CREAM =4.5 LBS. OF FAT 

 TEST OF CREAM = 30^ 

 tfx 100 = 30$ 



1OO LBS. OF 6# MILK 

 CONTAINS 6 LBS. OF FAT 



5 LBS. CREAM 



85 LBS. 



SKIM-MILK 



15 LBS. OF CREAM = 6 LBJ.OF FAT 

 TEST OF CREAM -40<fi 

 Y5 x 100 = 40$ 



FIG. 14. 



tion, therefore, that affects the richness of the milk will also influ- 

 ence the richness and the test of the cream. 



Conditions that May Cause Changes in the Richness of the 

 Milk. During the early summer months the milk is usually 

 comparatively low in butter-fat. This is caused by such factors 

 as the freshening of the cows, change from dry feed to succulent 

 pasture and a natural and inherent tendency of the cows toward a 

 decrease in the richness of their milk in early summer. Toward 

 fall and early winter the opposite is the case. The advanced state 

 of the period of lactation and the change from succulent to dry 

 feed cause the milk to become richer in fat. It is obvious, there- 

 fore, that in the fall and winter the cream test tends to be higher 

 than in spring and early summer. 



Again, it frequently happens that even in winter there is a 

 sudden drop in the cream test. This may be due to the fact 

 that some of the cows yielding rich milk dry up or that some cows 

 come in fresh or a new animal may be brought into the herd. 



The seasonal variations in the richness of the cream may be 

 reduced by turning out the cream screw a trifle in the fall and by 

 turning it in during the spring of the year. 



