MICRO-ORGANISMS AND ENZYM8 



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New York experiment station on this subject. The 

 experiments were made by treating 350 cubic centi- 

 meters of fresh milk at 84 F. with i.o cubic 

 centimeter of rennet solution, made by dissolving one 

 of Hansen's rennet-tablets in 150 cubic centimeters of 

 distilled water. 



This effect of acids upon rennet action is com- 

 monly explained by saying that the added acid dis- 

 solves the insoluble calcium phosphates of milk and 

 thus increases the amount of soluble calcium salts. 

 It is known that even carbon dioxid gas favors rennet 

 coagulation, due to its dissolving action on insoluble 

 calcium salts in milk. 



(3) Dilution of milk by water both delays rennet 

 action and renders coagulation less complete, because 

 the proportion of soluble calcium salts is decreased. 

 Addition of calcium chlorid or free acid to- milk thus 

 diluted not only hastens the time of coagulation, but 

 makes more complete the amount of milk-casein co- 

 agulated. Apparently, milk may be diluted more than 

 10 per cent with water before the time of rennet 



