FIRST STEPS IN CHEESE-MAKING 23 



temperature of the milk, (3) the acidity of the milk, 



(4) the composition of the milk, (5) the kind of 



cheese to be made, and (6) the temperature of 



curing (p. 61). In general, an amount sufficient 



to coagulate the milk fit for cutting in 25 to 35 - J J'- /r 



minutes should be used. Generally from 2}4 to 4 



ounces for 1,000 pounds of milk will suffice. 



(3) Method of adding rennet-extract and subse- 

 quent treatment. — Before being added to milk, the 

 rennet should be diluted with 40 times its volume ^ , 

 of pure, cold water. The object of this is to enable 

 one to distribute the rennet solution thoroughly 

 and uniformly throughout the mass of milk before 

 the rennet begins to coagulate the casein. Rcnne.t 

 acts more slowly when diluted with cold water 

 (p. 307). The milk should be thoroughly stirred 

 before the rennet is added. The diluted rennet 

 should be gradually poured the whole length of 

 the vat, and the milk at once stirred again for 3 

 to 5 minutes. A rake may be used to advantage 

 for stirring. Then the surface is stirred gently to 

 keep the cream from rising. All motion of the 

 milk should be stopped as soon as, or before, coag- 

 ulation starts. The vat should be covered to pre- 

 vent cooling at the surface and to keep out flies 

 and dust, and then left undisturbed until ready for 

 cutting. 



Causes of imperfect coagulation. — By imperfect 

 coagulation, we mean (i) incomplete or delayed 

 coagulation of casein, shown by slimy or gelatin- 

 ous appearance of the coagulated milk and a curd 

 containing too much whey; or (2) variation In de- 

 gree of hardness in different portions of the mass 



