98 DAIRY CHEMISTRY 



ferments which are also called enzymes. The in- 

 soluble or organized ferments are mainly bacterial 

 bodies of definite form and structure propagated 

 from a spore or seed. These organized ferments 

 develop in milk, meat, or any other suitable mate- 

 rial if conditions as to temperature and moisture are 

 favorable. The chemical ferments, or enzymes, are 

 products of living organisms capable of producing 

 ferment changes. Chemical ferments cannot be 

 seen with the microscope ; they are simply chemical 

 substances capable of inducing fermentation changes 

 without entering into the composition of the material 

 or giving up any of their own substance to the re- 

 acting bodies. Milk contains a tryptic-like ferment 

 or enzyme, which peptonizes the casein and other 

 proteids, forming proteoses and other soluble bodies. 

 In the curing of cheese, it has been found that the 

 ripening process can be carried on entirelj^ by these 

 soluble ferments and at a lower temperature than 

 required by the organized ferments or bacteria. The 

 process of cheese curing at a low temperature. is akin 

 to the curing of meat in cold storage. 



Experiments on a commercial scale have shown 

 that cheese can be cured at a temperature of less 

 than 50° F., resulting in the production of a better 

 quality of cheese, less shrinkage in weight, and less 

 loss of solid matter than by curing at a high tem- 

 perature. As a result, the cold curing of cheese has 

 gradually replaced the old process of high tempera- 

 ture curing. This is an advantage also in that less 



