194 Milk and Its Products. 



down or rendering soluble the casein and in the 

 development of the characteristic flavors peculiar to 

 good cheese. These flavors are almost entirely de- 

 veloped during the ripening process. The ripening 

 is brought about by a series of fermentations that 

 goes on in the cheese. It is not well understood 

 just what these fermentations are ; but it seems 

 evident that at least in the early stages of the 

 curing, lactic acid germs are active, although the 

 greater majority of these disappear after a short 

 time. During the ripening process, oxygen is taken 

 up and carbonic acid given off. The quality of 

 the cheese is best when the ripening process goes 

 on graduall}^ and continually. The higher the tem- 

 perature the faster the ripening will go on ; an 

 extreme temperature of 65° or 70° giving the best 

 results. At the end of from four to six weeks the 

 casein will be so broken down that the cheese is 

 fairly digestible and fit for consumption, though if 

 kept longer under good conditions the cheese will 

 improve for three or four months, and then if kept 

 moderately cool, and in not too moist nor too dry 

 an atmosphere, it may be kept one or two years. 

 During the early part of the curing process the 

 cheeses should be turned upon the shelves every day 

 until a sufficient amount of water has evaporated, 

 so that they no longer tend to lose their shape. 

 Difficulties Wkely to occur in cheddar cheese mak- 

 ing. — The chief difficulty in cheddar cheese making 

 comes from the presence in the milk of germs 

 which produce fermentations that are undesirable. 



