FROM CHURN TO PACKAGE 133 



of lactation, the volatile acids were the highest and the 

 olein was the lowest. They assert that the volatile 

 acids decrease and the olein increases as the period ad- 

 vances. This subject is more fully discussed in paragraph 

 99. There is a close relation between the size of the fat 

 globules and the condition of the fat, from the standpoint 

 of the churning quality of the cream. 



99. Size of milk-fat globules. — The size of the milk- 

 fat globules has a marked effect on the churning quality 

 of cream. The large fat globules come in contact with 

 each other more readily than do the small ones. The size 

 of these small divisions of fat is probably affected by the 

 same factors that control the condition of the milk-fat. 

 Very often a " stripper's " cream is difficult to churn 

 because the fat is hard and the globules are small. Hun- 

 ziker, Mills, and Spitzer ^ say that the size of the fat 

 globules is controlled largely by breed, period of lactation, 

 and by change of feed and other factors affecting the 

 physical condition of the animal. These investigators 

 add : " The Channel Island breeds produce milk with 

 much larger fat globules than the Ayrshires and Holsteins. 

 Milk from fresh cows contains larger fat globules than milk 

 from cows well advanced in their period of lactation. 

 Abrupt changes of feed temporarily increase the average 

 size of the fat globules." Eckles and Shaw ^ report the 

 following : " The stage of lactation exerts a marked and 

 uniform effect upon the relative size of the fat globules. 

 The fat globules are especially large immediately after the 



1 Hunziker, 0. F., Mills, H. C, and Spitzer, Geo., Moisture 

 Control of Butter — - 1, Factors not under Control of the Butter- 

 maker, Purdue Univ. Agri. Exp. Sta., Bui. 159, p. 356, 1912. 



2 Eokles, C. H., and Shaw, R. H., The Influence of the Stage 

 of Lactation on the Composition and Properties of Milk, U. S. 

 Dept. Agri., B. A. I., Bui. 155, p. 76, 1913. 



