Cheese has been a fascination of mine for some time. My penchant for it began in early childhood; my indiscriminate taste and the incredible array of potential pairings led it to be (more than a) staple in my hedonistic diet. My relationship has since changed (aged, matured) considerably: I mostly hear the Sirens’ song when the cheese is lauded as regional, representative, fresh, funky, personal. I switch between finding the texture appealing and appalling. This might just be a phase, but there is no way of knowing until time has passed.
Cheese starts as milk. Milk is mainly harvested from cows, goats, sheep, and buffalo. The milk is pasteurized (heat treated to severely decrease the amount of microbes that can cause disease) and treated (homogenized) to make uniform and safe to consume. Sometimes, acid is added to the cheese to start the curdling process, but more commonly, starter culture is added to this treated milk. This culture contains bacteria that convert the lactose (sugar) in the milk to lactic acid. Then rennet is added, which is an enzyme (sourced from the stomach of cows and other mammals, but has alternative sources such as fig leaves and melons) that causes the milk to coagulate. Coagulation happens because rennet contains chymosin, an enzyme that curdles the casein protein in milk.
The coagulated and thickened mixture is drained to separate the liquid that emerges (called whey) from the milk curds. The curds are then cut into different sizes. These curds are the prototype of the different types of cheese. Large curds are cooked at low temperatures, making soft cheeses (ricotta, marscapone). Smaller curds are cooked at high temperatures, making harder cheeses (parmesan).
The curds are cooked and stirred with the whey liquid until the target temperature and firmness are achieved. Then the whey is drained off.
The cheese is pressed to finalize the shape and form. Thereafter, the cheese is salted or brined. Salting the cheese is a way of inhibiting bacteria growth, slowing down enzymatic activity, and forming the rind. It also changes the flavor profile of the cheese considerably. Brining is an alternate way to have the cheese absorb salt, usually done for harder cheeses.
Some cheeses are cured, or aged (Cheddar, Manchego, Parmesan). This matures its flavor and changes its texture. Usually, the cheese is cured in a controlled environment with set temperature and humidity. Most soft cheeses are aged for a much shorter time period, as an easy heuristic.
The variety in cheesemaking makes it a big optimization problem with multiple optimal solutions. The type of milk used changes the fat in the resultant cheese, which changes the flavor and texture. The starter culture used changes what type of mold and bacteria develop during fermentation and aging. The size and cooking of the curd partly determines the flavor profile and the texture of the cheese. The salt or brine used (and for how long the brine is in contact with the cheese) changes the moisture and rind. Aging brings about fermentation, bacterial growth, and flavor development.
And there are ever-increasing amounts of processing steps: using raw milk instead of processed milk, adding herbs and spices before aging, adding water during the processing of the curds, changing the diet of the cows that are milked, and so on.
It is no wonder, then, why cheese is so celebrated. Wrestling with all of these variables is daunting and aiming for a target cheese must be doubly satisfying: perfecting a process over countless iterations is almost meditative, and tasting a creation that has swaths of history, hard work, and sheer time invested results in an experience that is greater than the sum of its parts.