"Homemade Cheese"

Cheesemaking techniques vary depending upon the intended final use or consumption of the cheese.  Cheese can have widely varying characteristics.

Italian mozzarella-type cheese, used in pasta dishes, must have good melting quality and mild flavor. Hard cheese such as Romano and Parmesan must be dry with distinct flavor. Mexican cheese, often used in fried foods, must be stable at high temperatures. The variety among cheeses has arisen from differences in milk quality, diversity among native microflora (microorganisms naturally occurring in a given region) and differences in handling during processing. In North America cheese is usually made from the milk of cows (Bos taurus) or goats (Capra aegagrus). In India cheese is often made of milk from water buffalo (Bubalus arnee). Yak (Bos grunniens) cheese is made in the interior of Asia.

Cow’s milk consists of 88% water with 3.7% fat, 3.4% protein, 4.8% sugar (lactose), and 0.7% minerals and vitamins (USDA, 2005). The process of making cheese involves forming a curd from milk solids such as fats, protein and minerals that are separated and concentrated (Hill, 2006). The discharged liquid, whey, contains most of the lactose, water, simple proteins, minerals and vitamins (Hill, 2006). About 10 pounds (1.25 gallons) of milk are required to make one pound of cheese.

Making cheese is a dynamic process, affected by time, temperature and the bacterial culture (lactic acid bacteria) and coagulating enzyme (rennet) that are used to concentrate and separate the casein (milk protein) and fat from the whey. Exceptions to this include cheeses such as Queso Fresco or Queso Blanco (traditionally eaten in Latin American countries) and Paneer (traditionally eaten in India), which are made without bacterial cultures or rennet. These cheeses are made by curdling hot milk by adding an acid such as vinegar or fruit juice. This type of fresh cheese is simple to make and has higher yield because all the whey proteins normally lost are included in the cheese.

The enzyme rennet causes casein to form chains and to develop a mesh-like network or gel, trapping water and fat. This semisolid gel is the curd. When the gel is firm enough, it is cut into small pieces and, after cooking, the whey is removed. The whey may be partially drained from the curd and the curd washed with water to increase its moisture content. The temperature during cooking and handling of the curd affects the texture of the curd and the type of final product. When the curd has reached the desired moisture and acidity, salt can be added. Salting may be achieved through brine, as with Gouda; surface salt, as with Feta; or dry salt, as with Cheddar. After salting, the curd may be partially drained and again washed with water to increase the moisture content. When the curds have reached the desired moisture and acidity (pH), the whey is separated from the curd.

The cheese curd formed is a result of bacterial action on lactose converted to lactic acid. The acid acts as a preservative, removes water from the cheese curd, and develops cheese texture (Hill, 2006). Initially the enzymes from native microflora produce the flavor components, which change during aging.

Commercial cultures have been developed to produce a particular cheese type. Yogurt and buttermilk contain live bacteria that can be used as a culture to make cheese.

Once the whey is removed, the curd is allowed to stick together, forming a mat. The mat is transferred to a hoop or mold lined with cheesecloth, which contributes to the final shape. The mold can be pressed to form a dense cheese (Cheddar) or can be left to settle under its own weight to have an open texture (Feta).

Soft cheese can be made at home without specialized equipment. Because soft cheese contains over 45% water, it is highly perishable and has a refrigerated life of only five to seven days.