Page:The story of milk.djvu/123

 maturity of the curd, the threads will break at a length of from ½ to 2 inches. Usually fermentation is considered sufficient when threads 1½ inches long are formed by this test.

Salting.—The matting is then interrupted by breaking up and salting the curd. This can be done by hand or by a curd-mill which cuts or breaks up the curd and permits a thorough mixing in of the salt. Two or three pounds of salt to one hundred pounds of curd, or the curd from 1,000 lbs. of milk, is the usual ratio.

Curd mill

Pressing.—Stirring and cooling the salted curd to about 80° F. makes it ready for packing into the hoops in which it is to be pressed. The hoop is usually a cylinder of heavy tin with a "follower" of wood on which the pressure is applied. Before the curd is put in, the hoop is lined with cheese-cloth which remains on the cheese, when it is taken out. The press mostly used in the factory is the continuous pressure "gang-press" in which a number of cheeses can be pressed at the same time.

Curing.—After 18 hours' pressure the cheese is taken out of the press and out of the hoop, weighed and placed on a shelf or table in the curing room. For the first week or ten days it is kept at a temperature of about