The terms "cooked" and "uncooked" cheese can be confusing, as both involve heating the curds. So what exactly is the difference between cooked and uncooked cheese?
Both cooked and uncooked cheese begin the same way, as milk. The best cheeses come, naturally, from the best, purest milk. It takes about 10 pounds of milk to make 1 pound of cheese, and the cheesemaker will carefully weigh and inspect the milk before the process begins.
The next step is to pasteurize or heat treat the raw milk to ensure quality, safety, and uniformity. The cooking or "uncooking" are different than pasteurization, which occurs at the very beginning of the cheesemaking process and at a higher temperature.
"Good" bacteria, or the starter culture, is then added to begin the cheesemaking process. These bacteria help to determine the flavor and texture of the resulting cheese. Then, a milk-clotting enzyme called rennet is introduced, which coagulates the milk, resulting in a custard-like mass.
The cheesemaker will then cut this into smaller pieces to begin the process of separating the whey, or liquid, from the curds, or milk solids. Then, the curds are handled in a few different ways, depending on the cheese. This is the point at which heating the curds occurs and where the process separates into "cooked" or "uncooked" cheeses.
Cooked cheese is made from smaller-cut curds that are heated to a higher temperature to affect the texture of the cheese. Heating curds helps expel as much whey (moisture) as possible. Many types of cooked cheeses have a firm or dense texture.
Examples of cooked cheese:
The curds for pasta filata cheeses, such as mozzarella and provolone, are also cooked. Then, the rubbery curds are stretched, pulled, and cooled in water.
Uncooked cheeses are made from larger-cut curds that are heated gently at a lower temperature. This also expels moisture (whey) from the curds, but not as much.
Examples of uncooked cheese:
Continuing the Cheesemaking Process
Cheesemakers cook and stir the curds and whey until the desired temperature and firmness is achieved, and then the whey is drained off, leaving a tightly-formed curd. How the curd is then handled and salted is specific to the variety of cheese.
Pressing helps to complete the curd formation and results in the characteristic shape of the cheese. Pressing is either done mechanically or by the weight of the curd itself (e.g. Colby and Feta). Pressing takes between three and 12 hours, depending on the desired size of the cheese shape.
The final step is curing, which is specific to the type and style of the resulting cheese. Curing is when cheeses are aged. It creates the fully developed taste and texture of the cheese. Curing takes place in a specific heat and humidity controlled room and may take weeks or even years.