DAIEY PRODUCTS. 185 



completely introducing air into the whole mass, and by this 

 means eliminating and throwing off more impurities and ani- 

 mal matter by means of the oxygen introduced. The custom 

 of aerating the milk when kept in quantities of 200 or 300 lbs. 

 by means of an air-pump has been practised, it is said, with 

 highly satisfactory results, and the milk so treated not only 

 keeps better and makes more cheese by one-tenth, but a supe- 

 rior article also. From our own observation we are led to 

 believe that the statement is not far from the truth. 



Rennets. — Much has been said about rennets, and it is 

 worthy of remark that a decided improvement has been made 

 in their preparation". The active principle of the rennet to 

 produce coagulation is what we want in its perfect state, — 

 nothing more, nothing less. This active principle lies on and 

 is imbedded in the mucous membrane of the stomach, which 

 we call rennet. All that we want of the rennet-skin is to hold 

 these minute particles of coagulating matter in reserve until 

 they are needed, soaked and thereby separated from the mem- 

 brane and skin. If we could by any means separate this 

 inner coating and by any process thereby preserve onlj^ what 

 we want, much trouble would be avoided. In our present 

 knowledge of the matter the only correct rule to follow is to 

 remove every particle of the rennet except the bare skin to 

 which the mucous membrane is attached, including the entire 

 neck, which is generally loaded with fat and has but little 

 membrane. It is a matter of high importance that we pre- 

 vent any dried fat or fleshy substance in which decomposition 

 has taken place from finding its way into the milk-vat, then 

 into the cheese, where in the course of time its hidden power 

 for harm makes its appearance. 



Our experience teaches us that too much rennet may be 

 used; if so, the cheese w411 cure raj^idly, be soft and salvy, 

 and consequently decompose early. So, also, if not enough 

 is used to permeate the whole mass rapidly, the cheese will be 

 hard and may present something the appearance of skim-milk 

 cheese. 



I am satisfied that at the present time there is no way for 

 the Massachusetts cheese-maker to compete with the Western 

 producer but by making a cheese of a higher standard of ex- 

 cellence. Can this be done ? And what is the standard of 



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