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 the same size as Gruyère and thus has an intermediate place between the large pressed cheeses of commerce and the fancy cheeses above mentioned.

Gorgonzola cheese is a very familiar cheese made in Italy and belongs to the same class as the two preceding ones. It is in one sense a fancy cheese and yet is made in such quantities as to belong rather to the commercial variety.

Bacterial Activity in Cheese.—Modern science has led to the conclusion that the ripening of cheese is due principally to bacterial activity. The changes which take place in the chemical and physical properties of cheese materials, the flavor and aroma which are developed, the production of mould and other growths are marks of the activity of organisms of different character, living and unorganized. Due credit must be given to the enzymic (unorganized) action in these processes and the enzymes are not regarded as living organisms but, on the other hand, as catalytic agents inducing chemical changes similar to those produced in starch by the action of diastase. The peculiar flavors of cheeses which are found in different kinds have been ascribed in late years almost exclusively to the character of bacterial activity. This assumption is perhaps correct, but it must not be forgotten in this connection that the same species of bacteria, in changed environments, does not always produce the same results. The activities of bacteria are peculiarly sensitive to the environment, such as change of temperature, physical conditions of different kinds, locality, and other factors of a complex nature, making up the total conditions in which the organisms live. For this reason the attempts to produce peculiar cheeses which belong in particular localities in other localities have not been gustatorily even if technically successful. It is true that cheeses may be made of the types mentioned, having some of the general characteristics but lacking that indescribable something which after all gives true character. Just as it is impossible to make a Rhine wine in California or a Bordeaux wine in New York so is it impossible to make a Cheddar cheese in Ohio or a Camembert cheese in Connecticut.

Number of Bacteria.—The number of bacteria, per gram, which appear in cheese varies according to the age of the cheese, conditions under which it is made, temperature, etc. The usual number of bacteria in one gram of cheese varies from five hundred thousand to nearly one hundred million (21st Annual Report of the Wisconsin Agricultural Experiment Station).

Ageing does not seem to increase the number of organisms, since it has been found by some observers that the maximum number present in cheese is found at the time it is taken from the press. It is difficult also to properly sample a cheese for the number of bacteria, since they are unequally distributed in different parts thereof, and the trier, by means of which the sample is secured, may show largely differing numbers in different parts of the same cheese. During the process of curing, especially if the curing be at a high temperature,