I want to delve a bit more into cheese making fundamentals, and how four simple ingredients (milk, cultures, rennet/coagulant, salt) can produce a seemingly infinite number of cheeses.
After my article on Hard Cheeses, many people wrote in wanting to know where Cheese X, Y or Z (Pecorino, Asiago, and Manchego to name a few) fit into my broad strokes overview. I thought a further contextualization of cheese making would help. For those of you who want to supergeek-out I heartily recommend Harold McGee’s On Food and Cooking, which has, among many things, a brilliant flow chart encapsulating cheese making.
There are two major push buttons to consider when exploring the nuances between various cheese types. The first is the use of cultures (often called enzymes on the ingredient label), otherwise known as starter or, simply, bacteria. The second is the manipulation of curd during the make process, as detailed in Hard Cheeses with steps like cutting, stirring, and pressing.
Cultures are the first ingredient in turning liquid milk to solid curd that can become cheese. Their initial role is in the process called acidification, wherein bacteria are added to the milk to convert its sugar (lactose), into lactic acid. Allowed to happen slowly (over 12-24 hours) acidification alone will separate cream from milk and begin to solidify the liquid. In crudest terms, the milk begins to sour, turning progressively chunky as it does so.
There’s another dimension to cultures, however, that’s less talked about but far more miraculous. Their role isn’t simply to convert milk’s sugar into acid. It’s to unlock specific flavors, and cheese makers act as magician-curators in concocting a unique culture blend to tease out desired flavors of, say, cooked fruit or toasted nut. To be clear, the bacteria themselves don’t determine the flavor but they contribute to the breakdown of fats and proteins in flavor-determining ways. In many cases these bacteria lie dormant through the make and initial aging process, activating many months into a cheese’s future and unleashing its greatest flavor potential. A particularly good, and readily available example of flavor-driving cultures, is the “Swiss” blend used in Beecher’s Flagship (which to most consumers resembles a block of cheddar). The cheese is known for its sweet nuttiness, more akin to a Gruyere than a (mild, medium, or sharp) block Cheddar. Point being, a cheesemaker makes a determination about a cheese’s flavor potential long before s(he) is handling solid curd; this determination is often proprietary, there are hundreds of variables, and the same milk, taken through the same recipe, can and will taste radically different depending on the cultures used.
Then there’s the recipe: the steps a maker takes, the time allotted to each, the desired moisture and acidity levels along the way. Hard Cheeses talked about big picture steps like cutting, stirring, cheddaring and pressing, but here again there is the possibility for seemingly infinite variation, and the smallest differences impact a cheese’s final flavor and texture. Curd cut to corn kernel size will yield a moister, creamier and less ageable cheese than curd cut to rice grain size. The curd might be heated to a temperature of 105 or 130—that may be the difference between smooth pliability and waxy density.
Many of the most famous European cheeses now have a P.D.O. (protected designation of origin) meaning that the cheese must meet specific production and again criteria to be called by a specific name. This is a good way of understanding how a [hard, cut, cooked, pressed, Italian cow’s milk ] cheese could be Asiago or could be Parmigiano Reggiano. The breed of cow used, what they are fed on, whether the milk is pasteurized, how long the wheels are aged, how big they are, and so on all contribute to the final cheese, and differentiate it from a neighbor cheese a hundred kilometers away.
There is no cheat sheet for cultures, as these are determined by a cheese maker and aren’t known by the consumer, but a few flavor/texture generalizations based on cheese making steps are possible: