CHAPTER VIII. 
CHURNING. 
THE process of causing the particles of butter fat 
to unite into masses, so that they may readily be 
separated from the milk serum, is called churning. 
Such union of the partieles of fat is ordinarily 
brought about by agitation of the cream in a suit- 
able vessel, called a churn. If milk or cream be 
agitated at a temperature somewhat below the melt- 
ing point of butter fat, the particles of fat, as they 
pass by one another, agelutinate themselves into 
masses, and, the process beng continued, the first 
formed massex continue uniting, until finally the 
whole body of fat may be brought together in a prac- 
tically solid mass. The conditions influencing the 
separation of fat in this way are, first, the viseosity 
of the milk; second, the ripeness of the e¢ream ; 
third, the nature of the agitation; fourth, the qual- 
ity of the globules of fat. 
The viscosity of the milk. —The viseosity of the 
milk affects the churning, in that it tends to keep 
the particles of fat from moving freely upon one 
another, and in that the viscous portions of the 
milk, notably some of the albuminous matter, form a 
more or less dense layer about the fat globules, 
Digitized oy Migpsonte 
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