242 



CHURNING AND WASHING BUTTER 



temperature will vary a great deal in different localities. The 

 hardness of the fat depends upon (i) the season of the year; 

 (2) the individuality of cow; (3) the stage of lactation; and (4) 

 the kind of food fed to the cows. All these factors influence the 



melting-point of butter-fat. The 

 higher the melting-point of the 

 butter-fat is, the higher the churn- 

 ing temperature, and the lower the 

 melting-point of the fat, the lower 

 the churning temperature. 



i. During the spring the cows 

 yield milk containing a larger pro- 

 portion of soft fats; consequently 

 the churning temperature is always 

 lower in the spring than in the fall 

 or winter. During winter, when 

 the cows are fed on dry food chiefly, 

 the harder fats increase in quantity, and consequently a higher 

 churning temperature is necessary during that time. 



FIG. 87. Sectional view of Perfec- 

 tion working butter. 



PIG. 88- Disbiow churn (Davis- Watkins Dairymen's Mfg. Co.) 



2. Some animals produce milk containing a larger propor- 

 tion of softer fats than do other animals. It is said that the 

 difference in this respect is more marked in certain breeds. It 

 is maintained that the cows of the Jersey breed produce milk 



