CHEDDAR CHEESE MAKING 279 
After the color is thoroughly incorporated, add ren- 
net extract at the rate of about three and one-half ounces 
per 1,000 pounds of milk. The rennet extract should be 
diluted with water to the extent of at least five times its 
own volume before adding it to the milk. After the 
rennet extract has been thoroughly stirred in, the milk 
should be allowed to stand undisturbed until sufficiently 
curdled to cut. The temperature at the time of adding 
the rennet should be 86° F. 
The amount of rennet extract to be used is determined 
by the quickness with which the cheese is to ripen. If a 
quick ripening cheese is wanted, add about 4 ounces per 
1,000 pounds of milk. If a slow ripening cheese is de- 
sired, add 2% to 3 ounces per 1,000 pounds. 
While the milk is curdling it must be kept well cov- 
ered to keep the surface layer warm. 
Cutting the Curd. To determine when the curd is 
ready to cut insert the forefinger, slightly break the curd 
with the thumb, and move the finger in the direction of 
the break and parallel to, and half an inch below, the 
surface. If the whey in the break is clear, the curd is 
ready to cut; if milky, the curdling has not progressed 
far enough. The cutting is done as follows: First cut 
the curd in horizontal layers with the horizontal knife; 
next cut lengthwise and crosswise, alternately, with the 
perpendicular knife until the curd cubes are about three- 
eighths of an inch on a side. 
Warming and Stirring the Curd. Immediately after 
cutting, stir the curd very gently, yet enough to prevent 
the particles from matting together. Run the palm of 
the hand along the sides and bottom of the vat to remove 
any adhering curd. After 10 minutes stirring, gradually 
apply heat and raise the temperature to between 98° and 
