Cheese. It comes in may shapes and sizes. From the small wax covered baby bells, to cheese in a can. Yet, how are all those different kinds of cheeses made? One word, enzymes.

Cheese starts its life as milk. Be it from cow, sheep or goat, it undergoes a process called fermentation. Milk can by itself ferment into very foul smelling cheese if left unattended to for a long enough period of time. Yet in cheese making, this process is sped up with the aid of a bacterial culture that produces lactic acid, and rennet. The left over chunk are then filtered and pressed into an edible cheese. Now that was an extremely simplified version of how cheese is made. The actual process is slightly more complicated.

The first step is to make any type of cheese, is to lower the acidity by lowering the pH. This is done by introducing bacteria which feed on the lactose in the milk, and produce lactic acid. Acidity is important as it determines the consistency of the cheese. Too much acid and the cheese will be crumbly, too little and it will be too soft.external image cheesemaking_3.jpg

The next step is to coagulate the milk, separating the curds (solid chunks) and whey (liqui d). With the change in pH, the milk will naturally start to curdle and coagulate, this is becau se the lowered pH level changes the shape of the casein proteins in the milk, making them collect together and form chunks. This process is sped up with the aid of rennet which contains the enzyme chyomosin. This step takes about one hour.

A little history lesson on rennet. Rennet, until recently was collected from the fourth stomach lining of calves (baby cows). Not until the recent onset of genetic engineering, was lab made rennet made available. As a result, only 30% of cheeses made in the United States are produced with natural calf stomach rennet.
external image man_with_wheels.jpg
The curd is then heated an d cut in order for the whey to leak, and be s queezed out, and then filter ed with the aid of a cheese cloth. The consistency of the curd can now be changed by regulating the amount of water that is in the curd. The less water there is, the harder the curd will be. After this, the curd is salted to reduce the growth of microbes. After salting, shaping the curd into wheels, bars, or whatever can begin.

The next step in the process is to ripen the cheese. Aside from the type of milk used, this also plays an important role in how the cheese will taste. In this phase, different bacterial colonies are added to the cheeses in order to change their chemical composition and their taste. Brie cheese for example, are coated with Peninciullium spores. This is called surface ripening, because only the surface of the cheese is coated with a bacterial wash. The other type is washed rind. With this type of cheese, the atmosphere of the curing chamber of the cheese itself contains the bacteria. This kind of cheese must be washed regularly to avoid drying out. Rinds protect the interior of the cheese, sort of like a cheese skin. They are formed by being formed naturally, or treated with salt, oil or covered with paraffin wax or bandages. This process can take from anywhere from 6 weeks for mild cheeses, to 5 months for sharp cheeses.





For more information about the aromatic and delectable world of cheese, take a peek at these websites (which were also used to aid in the creation of this page):
http://www.geocities.com/Heartland/Cottage/1288/intro/Intro.htm
http://www.mistupid.com/food/cheese.shtml
http://www.vermontdairy.com/farm_to_you/cheese
[[http://www.geocities.com/Heartland/Cottage/1288/intro/Intro.htm|]]Enzymes and Cheese (Sean M.