106 Dairy Bacteriology. 



with the curd. The jars are kept at a temperature of 

 100 to 105 F., since this temperature is favorable to 

 growth of the bacteria that are sought, the gas-forming 

 organisms. At the end of ten to twelve hours, the jars 

 are examined; if the curd is solid, the texture firm, not 



FIG. 24. CURD TEST. 



The curd obtained from milk containing many gas-forming 

 bacteria. The irregular, angular holes are mechanical, due 

 to the imperfect fusion of the pieces of curd. 



mushy or slimy on the surface, if the odor is agreeable, 

 it indicates that the milk contains few or none of the 

 undesirable forms of bacteria. If the curd is full of gas 

 holes, it is apparent that undesirable bacteria are pres- 

 ent and under such circumstances the curd will not have 



