Cheese is a type of food produced from animal milk that is popular all around the world. It results from the coagulation of casein, which is a milk protein, and can have many variations in shape, flavour or texture. The milk of several animals can be used to produce it, most often the one of cows, sheep, goats or buffaloes. The production method varies depending on the cheese type but it is common practice to first make the milk acidic and then to trigger coagulation by adding an enzyme named rennet. The solid part is then pressed into a form, while the liquid one is discarded or used for other dairy products. In cooking, cheese typically melts. It is not uncommon for some varieties to have mold on the outside or even on the inside.
Variants of cheese are produced in basically every country in the world and thousands of types exist. Many factors influence the taste and texture of cheese: the fat content of the milk, the animal who produced it, the bacteria and mold used, the processing and aging, the pasteurization or lack of it and even the diet of the animal. Many types are flavoured using spices, herbs or they can be smoked. Color can also be changed, for example adding annatto makes cheese red or yellow. Garlic, black pepper, cranberries or chives are some of the most common ingredients used to flavour cheese.
In some cases, lemon juice, vinegar or other acids are added to the milk in order to curdle it. Milk usually becomes acidic due to the action of bacteria who transform the sugars in its composition into lactic acid. Curdling is accelerated by adding rennet to milk. It is also possible to use vegetarian products as an alternative to rennet. Some of these are extracts from plants in the thistle family (Cynara), while others are produced by fermenting Mucor miehei, which is a type of fungus. Most cheese is produced in dairy regions, in order to profit from the lower prices and the availability of fresh milk.
Cheese has long been considered a very valuable food. It has a long shelf life, is easily transported and provides a rich mix of proteins, fats and essential minerals such as calcium or phosphorous. By contrast, milk can't be preserved for too long and is a lot more bulky. Not all types of cheese have a very long shelf life, some of them actually have to be consumed in three to five days after the package is opened. As a general rule, hard cheese varieties last longer than soft ones, for example Brie. Packaging some cheeses in a rind for protection allows long-term storage, so the producers can sell them when the price is right. Cheese is used in numerous recipes and dishes and some varieties like parmesan are often a must-have ingredient.
A key compound in the manufacture of cheese is rennet. This is actually produced by all mammals in their stomach and consists of a mix of enzymes. It is usually sourced from young animals, in particular calves. Vegetarians and people who follow kosher diets eat cheese produced using rennet alternatives that are not of animal origin. Rennet separates milk into curds, which are solid, and the liquid whey. This is due to the action of an enzyme named rennin.
The solid curds are gathered and pressed, in order to dry them further by eliminating most of the remaining whey. Cottage cheese is a dairy product that consists of raw curds, with a loose texture. This product is not completely drained, so some whey is still present in it. Cottage cheese has a very mild flavour compared to other cheese types, which makes it popular with kids. It is also very easily digested.
In most cases, the curds continue to be pressed until all of the whey is squeezed out and they become dry. The result is known as farmer's cheese and it is a soft and fresh product with a mild taste that can be spread on bread. Chevres, Neufchatel and Cas are some famous brands of fresh cheese. The downside of farmer's cheeses is that they have a short shelf life. Refrigeration doesn't help much, while heavy use of preservatives alters the fresh flavour.
After the curds become dry, the next step is to pack them into a mold, weight is also usually regulated at this time. This is when the various types of cheese are created. The final result depends on many factors, such as the fat content, animal origin, the diet of the animal, pasteurization, the presence of certain bacteria or mold, as well as the aging time. In some cases, for example Greek feta, the cheese is then placed into brine. Cheese can be flavoured by smoking but there are many other methods, for example mixing the curds with spices and herbs or adding some wine.
The flavour is influenced by how long the cheese is aged. The high acidity of cheese kills most bacteria but molds are able to survive it, which explains the very strong flavour. One of the reasons why there are so many varieties of cheese is that molds are specific to certain regions. Some molds are only found in a particular cave, so a cheese variety can only be produced there.
Cheese is an extremely diverse type of food and the number of varieties is almost endless. In order to make a difference for consumers, famous types are protected by state governments through the so-called appellations of origin, which only allow the region name to be used to specific products. For example, Roquefort cheese can only be made in the Cambalou caves of France, in the presence of Penicililum roqueforti.
There are actually so many types of molds in cheese that we haven't been able to identify all of them so far. There are multiple strains in a single cheese type and even in the same cave there can be different species depending on the exact location. Many expensive cheeses are artisan products, since they require constant care, a specific location and delicate crafting in order to achieve the final result. According to some experts, most famous cheeses are extremely gooey and smelly, with a very strong flavour that is just the end result of a controlled period of decay.
Cheese is extremely rich in calcium, the mineral that is the main building block for bones and teeth. However, the lactose content is quite low and aging the cheese reduces it even further. Since lactose is a form of sugar just like glucose or maltose, it can have a negative effect on teeth health.
The second essential compound found in large amounts in cheese is the vitamin B complex. These vitamins play many roles in the body but are especially needed for joints and bones. Vitamin B is critical for the health of kids, elder people and women, in particular during nursing and pregnancy. It pairs very well with calcium because it facilitates its absorption.
The poor absorption of calcium can have very serious health consequences. It triggers the disease named osteoporosis, which reduces the mineral density of bones. It typically affects women after menopause but elder males can develop it also, as well as children with a very poor nutrition. In order to counter its effects, a rich supply of calcium, proteins and vitamins is required. Calcium must be properly absorbed, so simply taking calcium supplements is not enough. A proper diet is needed and cheese is one of the best possible foods in this case because it supplies all three required nutrients. This is why it plays a key role in the diet of people who suffer from osteoporosis.
However, cheese also has a content of cholesterol and sodium, which are known to be dangerous for heart health and hypertension in particular, so it must be consumed with moderation. The actual amount of fats and cholesterol is variable and is influenced by the type of milk and its quality. It must be noted that cheeses with the best taste also tend to have the highest content of fats. However, low-fat cheese is also available and has become more popular due to health concerns. Selecting the best type to buy is often a compromise between the flavour and the diet restrictions.
Sodium can be also very dangerous for some people. The actual amount in cheese depends on how much salt was added to the milk or as a preservation agent after its formation. In any case, the amount of sodium is generally too high for people who suffer from high blood pressure, so it would be a good idea for them to exclude cheese from their diet. It is not recommended for hypertensive people even if it actually provides a number of benefits for heart health. One example is the high content of vitamin B but cheeses with a reduced content of sodium and fats are known to decrease the levels of homocysteine, which is a dangerous compound linked to a number of heart conditions.
While many people want to lose weight, there are cases when you need to gain some, for example after surgery. Cheese is excellent in this case, because it provides a powerful package of fats, protein, minerals and vitamins. Proteins are the building blocks of muscles, calcium boosts bone structure, minerals and vitamins improve your metabolism while fats are needed for energy. You can gain weight quickly with the proper diet and a good amount of sleep.