In general terms, cheese is a concentrated food made from fluid cow's milk. In the process of cheesemaking, the casein protein component of the milk is induced to coagulate. The network structure formed entraps the milk fat globules, but allows much of the water and soluble components (whey) to drain out. Typically, casein coagulation is induced by a combination of acid production by starter culture organisms and also the action of the enzyme rennet.
The first step in the creation of cottage cheese is pasteurization of the milk. Cottage cheese is a fresh cheese, consumed without aging and so milk used must be pasteurized to ensure the safety of the cheese. Once the cheesemilk is prepared, starter culture is added to generate lactic acid from lactose. Acidification occurs until the pH is lowered to 4.6, which causes precipitation of the casein proteins.
Cream is produced by the centrifugal separation of milk. During separation, two streams are created, a highly concentrated milk fat stream termed cream and a non-fat stream of skim milk that can be further processed into evaporated or dried milk products. The fat content of the cream resulting directly from the separator typically ranges from 35-45%.Creams of different fat levels can be produced by standardizing (addition of a low fat stream to a higher fat stream to achieve a desired fat level) with skim milk.
Cheese is a concentrated dairy product made from fluid milk and is defined as the fresh or matured product obtained by draining the whey after coagulation of casein. In cheesemaking, the caseins are easily precipitated from milk in a variety of ways. In the manufacture of fresh acid-curd cheeses, the curd formation is obtained by the addition of food-grade acidulants.
Cheese is among the most ancient manufactured foods. More than a thousand cheese varieties are known throughout the world. This astounding diversity stems from a number of factors, including the type of milk used (cow, ewe, goat, caribou, buffalo, yak), the manufacturing process and local preferences. Some prestigious cheeses are labeled with an "Appellation d'Origine Contrôlée", a quality marking that certifies that a product has been developed in a given region following a stringent manufacturing process.
Evaporated milk is produced when milk is condensed to half its volume by removing part of the moisture in a vacuum evaporator. However, at this concentration, the milk is still susceptible to microbiological spoilage so the evaporated milk is packaged in cans and heat-sterilized.
The primary function of fermenting milk was, originally, to extend its shelf life. With this came numerous advantages, such as an improved taste and enhanced digestibility of the milk, as well as the manufacture of a wide variety of products. Historically the fermentation of milk can be traced back to around 10 000 B.C. It is likely that fermentation initially arose spontaneously from indigenous microflora found in milk.
Feta cheese is a salty, pickled cheese that has traditionally been made from sheep's or goat's milk but is now commonly made from cow's milk. Manufacture of feta from cow's milk involves the use of rennet and acid to form a curd. In the first step of the process, the milk used is first adjusted to 5% fat content by the addition of an appropriate amount of cream and then pasteurized. Starter culture and lipolytic enzymes (breakdown fat and help develop flavour) are added.
Scientific investigation in the field of modern nutrition has made clear the fundamental reasons why milk is an essential part of the human diet.
Mascarpone cheese is a rich, fresh cheese that is a relative of both cream cheese and ricotta cheese. Mascarpone cheese is prepared in a similar fashion to ricotta, but using cream instead of whole milk. The cream is acidified (often by the direct addition of tartaric acid) and heated to a temperature of 85·C, which results in precipitation of the curd. The curd is then separated from the whey by filtration or mechanical separation. The cheese is lightly salted and usually whipped.
