4 BULLETIN 576, U. S. DEPARTMENT OF AGRICULTURE 
trom the curd. The object of cutting and heating is to get rid of 
the desired quantity of whey and to remove much of the acidity, 
with the least possible loss of curd. The best method of cutting the 
curd is to use regular cheese-curd knives, described above, which 
cut the curd into fairly uniform cubes from which the whey can be 
expelled with but small loss of finely broken particles of curd pass- 
ing through the drain cloth. To break the curd or coagulum with a 
stirrer produces too many fine particles of curd, which are easily 
lost in draining. 
After the curd is cut, heat is turned under the vat, and the tem- 
perature is raised gradually to 115° or 125° F. At the Grove City, 
Pa., creamery, operated by the Bureau of Dairying, a temperature 
Fic. 1.—Stirring the curd during heating 
of 120° to 125° F. has given best results. Formerly a temperature 
of 95° to 105° F. was used for heating the curd; but when the cheese 
is made in large quantities 1t seems ‘better to use a higher heating 
temperature and then cool immediately with cold water. Variation 
in the heat requirement depends upon the quantity of milk, the 
degree of acidity, the length of the period of heating, and the 
texture desired in the cheese. The curd should be stirred gently at 
frequent intervals (fig. 1) to prevent its cooking on the sides ‘and 
bottom of the vat. A: wooden rake may be used for this purpose. 
The texture of cottage cheese is controlled by the temperature at 
which the curd is heated, the length of time heated, and the extent 
of draining. Considerable variation as to temperature and time of 
heating and draining is found necessary, depending upon the con- 
dition of the curd. 
