constituents of the milk, two of which, the sugar and the 

 casein, unlike the comparatively inert and stable fat, are 

 peculiarly subject to bio-chemical changes, as yet not fully 

 imderstood or studied by the chemist and the bacteriologist. 



It requires only slight modifications of the process of cheese- 

 making to produce marked differences in the finished product. 

 As a result, there are probably 100 distinct different varieties 

 of cheese made in various parts of the world, and at least 25 

 well-known classes, varying greatly in appearance, texture and 

 flavour — particularly in flavour. 



They vary in texture from the Schabzieger of the Swiss 

 Alps, so hard that it must be grated, or rasped, as the name 

 suggests, to the soft and creamy French cheese, like Brie or 

 Camembert; in the matter of flavour, there is the mild and 

 genteel Cheddar on the one hand, and the loud and vigorous 

 Limburger on the other ; and as for size, they range from the 

 dainty Neufchatel, a few ounces in weight, to the ponderous 

 Gruyere which may weigh over 100 lbs. 



While the preparation of cheese as an article of food is 

 undoubtedly one of the oldest of the technical arts, the science 

 of cheese-making is of very recent origin. Until only twenty 

 or thirty years ago, our knowledge of the art was almost wholly 

 empirical, having been handed down from father to son, or 

 more correctly speaking, from mother to daughter, each 

 generation adding its quota of experience to the rules which 

 then did duty for the more exact knowledge that is available 

 to the cheesemaker of the present day. 



The brilliant researches and discoveries of Pasteur, 

 although they did not include a study of milk, nevertheless 

 blazed the track along which other scientists have followed 

 to show us the why and the wherefore of many of the changes 

 that take place in milk and its products. We know now that 

 the profound changes which result from milk fermentations are 



