252 BOARD OF AGRICULTURE. 



" In most rennets the amount of foul odor is so great that the coal 

 will soon become saturated and need changing." 



Hoio Cheese Cures. Turning now to the address of Prof. Cald- 

 well, w.e find the discoveries of Mr. Arnold carried into the pro- 

 cess of curing cheese. The little globules which he found in 

 rennet, the Professor tells us are the spores or seed of the micro- 

 coccus, which is one of the various forms of the common blue 

 mould. The spores are not only found in rennet, but exist to 

 some extent in the blood of all living animals and in the milk of 

 the cow. Their multitudinous existence in rennet, and their rapid 

 development throughout the mass of milk, causes coagulation. 

 They feed on the nitrogen in the milk, and continue to propagate 

 in the cheese set on the ranges until the whole mass of animal 

 secretions is converted into one of the forms of the common blue 

 mould, which is a vegetable product. So it is a question for de- 

 bate 'whether ripe, mellow cheese is animal or vegetable food. 

 The quality of cheese depends very much upon the form of 

 development which the spores in the rennet take. If they take 

 the form which is found in vinegar yeast, we have a sour cheese. 

 If they take the form found in lactic yeast, we have a sour cheese 

 of a different kind. The development of alcoholic yeast must 

 give us a sharp cheese. If we can preserve a balance between 

 these, and the development does not get much beyond the form 

 known as putrefactive yeast — that is, if we can keep the cheese in 

 the first stages of putrefaction, until it is completely converted 

 into micrococcus — the inference is that it is in the most palatable 

 and nutritious condition. The direct path of development, accord- 

 ing to Prof. Caldwell, seems to be putrefactive yeast, the first 

 stage ; then alcoholic or lactic yeast, ; then blue mould. It may be 

 accompanied b}' three or four other products. It may pass through 

 other channels of development. But the end is blue mould. 



I do not wish to indorse or condemn Prof. Caldwell's assertion 

 that the spores in rennet and the spores of blue mould are the 

 same. Though similar in some respects, my impression is, how- 

 ever, that they will, on careful examination, be found to be dis- 

 similar. 



I do not pretend to have exactly indicated the different condi- 

 tions which a cheese may go through on the road to blue mould, 

 of which the active principle of rennet seems to be the seed, 

 assuming that Prof. Caldwell is correct. I only wish to show 



