The chemical properties of milk are due to the presence of acids and acid groups. The acidity tends to increase naturally due to the lactic acid fermentation (formation of lactic acid from lactose) and phenomena of lipolysis (liberation of fatty acids). It plays a key role in the processes of coagulation of milk.
This is the first product of milk processing that is coagulated due to the destabilization of the casein micelles, which may be agglomerated by enzymes, acids or by heat imbalances. From this a gelatinous mass is formed (curd) and a liquid called whey. The main factors that affect clotting are: temperature, acidity, salt levels in the milk and the quantity of rennet.
Casein is the most abundant protein in milk. It is a phosphor protein which is very important for the production of cheese in that it breaks down via the action of enzymes or acidity and starts the milk coagulation.
This is the phase in which the action of numerous factors (acidity, temperature, mineral salts present in milk) and the addition of rennet, causes the precipitation of caseins, the formation of the curd and the consequent separation from the whey.
Rind The rind is the outer layer or surface of the cheese that is formed during kilning, salting and then ripening. In addition to performing a protective function, it allows the formation of the cheese and the development of the organoleptic characteristics.
This is a complex organic substance that promotes certain chemical reactions. Milk in its native state contains about 60 different enzymes and some have considerable technological importance, not including the additional enzymes produced by the existing bacteria in milk.
These are micro-organisms (bacteria) that contribute to the acidification of the milk and the maturation of the curd. They are very important for the development of the organoleptic characteristics of the cheese as in the fermentation of the lactose and other key components of the milk. For this the milk is first pasteurized to almost totally eliminate bacteria and subsequently grafted selected milk enzymes.
A fundamental constituent of milk which appears in the form of spheroidal globules surrounded by a membrane rich in phospholipids and vitamins. The fat content of milk varies from species to species and its nutritional importance is related to energy and wealth of vitamins. It is an essential constituent of the cheese and helps to determine the aroma and flavour.
Milk is the fluid produced by the secretion of the mammary glands of female mammals. It is a complex mixture of substances of considerable biological and nutritional importance (proteins, fats, lactose, vitamins, salts, etc.). According to the Pure Food Congress held in 1910 in Paris, milk is defined as: “The integral product of a complete and uninterrupted milking of a well-fed, healthy, female ruminant. It must be collected on the property and must not contain colostrum. The designation of milk, without any simplification, will apply to cows’ milk “
This is milk sugar. On average, fresh cow’s milk contains 4.8.5, and its amount decreases in relation to the degree of fermentation of the milk. Its fermentation to lactic acid by the lactic flora is an important phenomenon because it influences the organoleptic characteristics of cheese.
This consists of the ageing of the cheese under controlled temperature conditions, humidity and time. This phenomenon determines, in addition to the texture of the cheese and the outer appearance of the form, plus the desired aroma and flavour.
An operation in which milk is drawn from various species of mammal. It can be manual or mechanical. A complete and unbroken milking plays a key role in the chemico-physical and biological content of the milk.
Eyes (holes) These are holes or cavities which are generated in the cheese as a result of fermentation with production of acidic gases, especially carbon dioxide. They are typically rounded and uniform, with a smooth, shiny surface.
Pasteurization Pasteurization is an operation by which all the pathogens are destroyed through heating, thus eliminating micro-organisms and saprophytes normally present in raw milk. This heat treatment must be of at least 15 seconds at a temperature not lower than 72 degrees. To verify that the pathogenic flora of the milk has been eliminated the phosphatise test is carried out.
Cutting the curd
A manual or mechanical operation by which the coagulum is cut with a thorn or a lyre, to separate it from the serum. The rupture occurs gently at first to obtain a large grain and successively smaller depending on how hard the cheese is to be.
There are three types of salting: “dry” when the surface of the cheese is sprinkled with salt, through immersion in brine or “boiler” which is the addition of salt directly to the milk or curd. The reasons for which a cheese is salted are different: to impart the desired taste, to improve the preservation of the cheese, to increase the nutritional value or to remove the whey still present inside the curd.
Whey is the liquid part that is separated from the curd as a result of the coagulation of the milk. This phenomenon is called purging and is realized through the mechanism of syneresis which results from the natural contractility of the clot, also due to different processes of the curd.