Dairy products, that is, milk products, include a large group of foods. Most of the functional foods are currently made from dairy products. Milk is a basic food normally obtained from the milking of cows or other animals, such as sheep and goats. Although there is an increasing trend to consume what is considered milk from oats, almonds or soy beans. Milk is made up of water, carbohydrates, proteins, fats, minerals and vitamins, being casein the main protein in milk and lactose the sugar in milk. The nutrients contained in the milk are in suspension, solution or emulsion.
The dairy industry generally applies a series of techniques for the elaboration of the products: thermization, filtering, homogenization, fermentation, pasteurization and curdling. Pasteurization may be emphasized. It is a thermal treatment for milk to a specific temperature during a certain period of time. It destroys pathogens and improves the quality. Another process, curdling, which is achieved through the physicochemical processes of flocculation, skimming and coalescence, is applied to the cheese processing.
There are many dairy products, for example yogurt, ice cream and cheese. Due to the demand, the dairy industry has currently focused on the production processes, taking into account that raw material is highly perishable. During processing, legal requirements must be fulfilled to obtain products suitable for human consumption. To that end, sensory, physical, chemical and bacteriological analyses are carried out. Naturally, the dairy products must have a good quality and characteristic odor, color and flavor that make the food attractive.