BACTERIA IN CHEESE-MAKING. 253 



distinguished by a radical difference in the method of manu- 

 facture. The first type includes the soft cheeses such as Lim- 

 burger, Camembert, Brie cheeses, etc. In their manufacture 

 the curdled casein is placed in moulds for shaping, but is sub- 

 jected to neither heat nor pressure. The curd is either cut to 

 pieces by special knives, thus allowing the whey to drain off 

 more readily, or it is simply ladled out of the curdling vat and 

 placed at once in the shaping moulds. The whey is allowed 

 to drain off through false bottoms or holes in the sides of the 

 moulds, but the mass is not subjected to any pressure. At 

 short intervals the mass is turned so as to rest upon a new sur- 

 face, and by the continuation of this turning for a few days, the 

 cheese becomes consistent enough to handle. The cheese is 

 then placed in the ripening room where a definite and constant 

 temperature is maintained. In this room it remains for some 

 days or some weeks, according to conditions, and is thus 

 ripened. Such cheeses are never made very large and they 

 ripen rapidly. They never become hard and are sure to decay 

 quickly after the ripening process is ended. They are there- 

 fore necessarily consumed as speedily as possible after ripening. 

 They decay so rapidly that they cannot be transported to great 

 distances and hence are not articles of export. They are 

 made chiefly in continental Europe. 



Hard Cheeses. The hard cheeses, which are more common 

 in the United States and England, differ from the soft cheeses 

 in being subjected to pressure and sometimes to heat. After 

 the casein is precipitated by the rennet, it is cut into fine bits 

 to release the whey, and then is sometimes subjected to a 

 moderate heat (110 F.). This heat changes the nature of 

 the curd, making it tough and elastic. The curd is then re- 

 moved from the whey as completely as possible, and placed in 

 large moulds in which it is subjected to a heavy pressure. The 

 pressure is increased at intervals for a few hours and there is 

 thus produced a very compact mass of hard curd conforming 



