16 CHEESE MAKING. 
or smaller glass jars, with perforated tops, which set in a frame 
in a watertank. Samples of the milk to be examined are taken 
in the various jars, which are then set in warm water in the wa- 
ter tank and raised to a temperature of 95° to 100° F. Ten 
Fig. 4.—The Wisconsin Curd Test. 
drops of rennet extract are added to each sample and when the 
milk has eurdled, the curd is broken up with a case knife. Care 
should be taken not to transfer the germs from one sample to 
another by the case knife or thermometer. As soon as the whey 
separates, it is strained off through the strainer top, leaving 
Fig. 5.—Apparatus for operating the Wisconsin Curd Test. 
the curd behind in the jar. The curd is then under the same 
conditions as a curd in the cheese vat, and the various kinds 
of bacteria will develop, giving their characteristic results. If 
the result te gas, it will show in the curd, or if it be a taint it 
will likewise be found there. Common Mason fruit jars and a 
