Milk has been consumed since the times of the Bible. With production dating back 6000 years ago, man depended on herbivorous animals to provide him with milk, meat, and clothing. Today, these animals still provide man with his most essential food components, including milk.
The cow is the most commonly milked animal in the world, because it is
present in nearly all countries. Milk is the only source of food for young
mammals during the first period of their lives. Milk provides both energy
and building material necessary for growth. The antibodies it contains
protect young mammals against infection.
The principal constituents
of milk are water, fat, proteins, lactose (milk sugar), and minerals (salts).
Milk also contains other substances such as pigments, enzymes, vitamins,
phospholipids, and gases. Milk also contains bacteria
through sick animals and/or through handling..
Before heat treatment was introduced, milk was a source of health hazard infections because of its perfect growth medium for microorganisms. In the middle of the 19th century, Louis Pasteur conducted fundamental studies on heat's lethal effect on microorganisms and the use of heat treatment as a preservative technique. Pasteurization of milk, as it came to be known, is "any heat treatment of milk that secures the certain destruction of tubercle bacillus (T.B.) without markedly affecting the physical and chemical properties of milk."
The higher the temperature and the longer the exposure to heat, the greater the changes. Appearance, taste, and nutritional values are the main factors that differentiate the various forms of milk on the market.
Click
here to learn about the highest to lowest qualities
of milk!
