ISO Dairy Bacteriology. 



growth, by changing the nature of the environment in 

 cheese by washing the curds on the racks with warm 

 water. In this way the sugar and most of the ash were re- 

 moved. Under such conditions the character of the bac- 

 terial flora was materially modified. While the liquefying 

 type of bacteria was very sparse in normal cheddar, they 

 developed luxuriantly in the washed cheese. The flavor 

 at the same time was markedly affected. The control ched- 

 dar was of good quality, while that made from the washed 

 curds was decidedly off, and in the course of ripening be- 

 came vile. It may be these two results are simply coinci- 

 dences, but other data 1 bear out the view that the flavor 

 was to some extent related to the nature of the bacteria 

 developing in the cheese. This was strengthened materi- 

 ally by adding different sugars to washed curds, in which 

 case it was found that the flavor was much improved, while 

 the more normal lactic-acid type of bacteria again became 

 predominant. 



Ripening Of moldy Cheese. In a number of foreign 

 cheeses, the peculiar flavor obtained is in part due to the 

 action of various fungi which grow in the cheese, and there 

 produce certain by-products that flavor the cheese. Among 

 the most important of these are the Roquefort cheese of 

 France, Stilton of England, and Gorgonzola of Italy. 



Roquefort cheese is made from goat's or cow's milk, and 

 in order to introduce the desired mold, which is the ordi- 

 nary bread-mold, Penicillium glaucum, carefully-prepared 

 moldy bread-crumbs are added to the curd. 



At ordinary temperatures this organism develops too 

 rapidly, so that the cheese to ripen properly must be kept 

 at a low temperature. The town of Roquefort is situated 



i Bibcock and Russell, 18 Kept. Wis. Expt. Stat., 1901. 



