In the manufacture of all of these types of cheese, troubles are likely to develop, due to an abnormal bacterial condition of the milk.
It will be seen from what has been said that the bacteria are essential factors in cheese ripening, and that the cheese industry, like the butter industry, may be called a true fermentation industry. Close co-operation must exist between the milk producer, and the maker so that the type of fermentation that goes on in the milk can be controlled. A recognition of the fundamental principles governing these fermentations, both normal as well as abnormal, is now regarded as an essential part of the training of the dairy manufacturer of today.
CHAPTER IX.
BACTERIA IN MARKET MILK.
Within the last decade attention has been especially directed toward the quality of milk that is furnished to the people in the cities. This has come about, in part, in connection with the demands made for better and purer food of every kind. These demands are reflected in the pure-food laws enacted by the federal government, and by the various states and municipalities. Another factor that has focused attention on the milk supplies has been the belief that it plays an important role in the production and distribution of disease, especially among children. The rapid growth of cities in all of the great countries of the world, the higher standard of living, and the greater demand for milk and other dairy products, has, of necessity, widened the zone from which the milk supply of any particular city must be drawn. Milk is now an article of export and of import; some of the great cities draw a portion of their supply from farms hundreds of miles away. This means that a longer time must elapse between the time of production and consumption, necessitating the exercise of greater care in production and handling in order to preserve the milk until it reaches the consumer.
In the past in the cities, as in the smaller towns at present, the supply was largely furnished by the producer directly to the consumer. This direct contact afforded the consumer the opportunity of informing himself of the conditions under which his milk supply was produced if he desired. The advent of the middleman in the business, and the gathering of the milk from many hundreds of farms, and its redistribution to thousands of homes has made it impossible for the individual consumer to learn anything of the conditions surrounding production. When the individual cannot protect himself against fraud and unhealthful conditions, it is the duty of the government to protect him. This is the theory underlying the modern control of food supplies, water supplies, and of living conditions in general. Acting on this basis the cities are seeking to control, to an increasing degree, the healthfulness and cleanliness of the milk supply.
Formerly such control as was given was largely with reference to the composition of the milk, the regulations providing that it should contain not less than a minimum amount of fat and other solids, and be free from preservatives. The more modern regulations are much more complex and touch every phase of production and handling that can, in any way, affect the value of the milk as human food.
Municipal regulations. The different cities vary widely in the methods employed to secure a satisfactory milk supply. Rules and regulations are adopted to which the producer and dealer must conform. In order to ascertain whether the regulations are being obeyed, two types of examinations may be made: first the inspection of the farms and of the plants of the dealers; second the examination of the milk itself with reference to its chemical composition, bacterial content and temperature.