Still, for better or for worse, all natural cheese is made using essentially the following process:
The Field
One often overlooked aspect of cheesemaking is the aspect of animal husbandry; how the animals are cared for and fed. Remember, cheese starts in the field, long before liquid milk is appears, there are a series of decisions made by farmers which have enormous impact on the flavor of the finished cheese: what type of animals to raise, which breed to bring on board, what to feed them, what kind of milking cycle to work with, how the milk will be transported from milking parlor to dairy.
The Milk
Liquid milk is the raw material a cheesemaker works with; its quality and character is one the most critical components of the flavor of the finished cheese.
With farmhouse or small dairy cheesemaking, milk may arrive both in the evening and in the morning. Many cheese recipes call for skimming the evening milk (yielding cream for the morning table) to be blended in the next day with fresh morning milk.
Over the last century or so most modern dairies have made the move to pasteurize their milk. Many of the best cheeses and certainly the most traditional (and quite often, the ones I like most) are still made from milk that is used is in its natural, raw, unpasteurized state.
Pasteurized or not, liquid milk is placed into a meatl kettle, or vat. Vats vary in size from small to enormous. Small cheesemakers might have vats that hold as little as a few hundred gallons of milk. It's known to cheesemakers as an "open vat" (a rather revealing retronym of a name which derives its meaning only in contrast to it's industrial age replacement, the "closed vat.") Dutch style vats are round, often sided with wood. In Switzerland round copper kettles are used. In Parma, cheesemakers work in cone shaped copper kettles. Cheddars and other English-style cheeses are generally made in rectangular stainless steel vats.
Commercial makers might view these tiny tanks as near antiques. Factories nowadays usually use closed vats to seal the milk off from the risk of external contamination. The closest the human hand gets to the milk in this industrual setting is touching the dials on the control panel, and opening the valves that allow the milk in or whey out of the vat.
Generally, the milk is warmed prior to the start of the actual cheese making. The warmer temperatures allow the natural bacteria in the milk to produce lactic acid from lactose in the liquid, in turn providing the proper acidity level for the soon-to-be-added rennet to do its work well, allowing the proteins in the milk to coagulate.
The Starter Cultures
Starters are sort of the big unspoken "secret" of the cheese world. It's not that anyone in the industry hides their use, but rather that few consumers seem to even know they exist; cheesemakers rarely discuss them in depth except with other cheesemakers (after all who would ask if no one knows about them?). Yet in the modern world, the selection and management of one's starter cultures can have a huge impact on the flavor of the finished cheese. To quote Dr. Davis: "If there is one aspect of cheesemaking which is more important than any other, it is the security afforded by a pure, vigorous starter." The effectiveness of starters may vary from region to region and breed to breed so one can't simply assume that an effective starter in one area will attain equal success elsewhere.
Starters are a relatively recent addition to the cheesemaking process, but today they are used almost universally. Back in the pre-Industrial era, cheesemakers relied-for better and for worse-on the natural bacterial behavior in the milk to make cheese. Rennet was added to coagulate the milk into curd, but beyond that the natural bacteria in the milk worked on their own to create the flavor of the cheese. Meaning wide ranging inconsistencies in the quality of the cheese; some days it worked, others it didn't, and no one really understood exactly why.
Commercial starter cultures came into use in 000000, around the time that pasteurization of milk was coming into use. Because pasteurization kills off all bacteria in the milk-both desirable and undesirable-it's important for the cheese maker to reintroduce enough bacteria to get needed flavor development in the milk. Today, cheesemakers generally purchase starter cultures from labs in powdered form. These bacterial cultures help build the flavor of the finished cheese. Selecting and handling of the starters from dairy company catalogs has become a meaningful component in crafting a quality cheese. Quality concious cheesemakers change starters from time to time in their search for better cheese, much as farmers rotate their crops to keep the soil strong. (For some blue cheeses-like Stilton-penicillium roqueforti, the mold may be added to the milk in powdered form at this stage.)
A handful of traditional cheeses are still made with starters cultured on site by the cheesemakers, usually using leftover whey from the previous day's cheesemaking. Essentially the process is akin to that used for making sourdough breads. In fact, in some parts of France, these traditional starters are known as levain, the same term that is used for a sourdough bread starter. Bacteria are left at warm temperatures overnight to develop, then added to the milk the following morning. In this way, the characteristic flavor of the cheese (and the characteristic touch of the maker) are handed down from day to day.
A Case Against the Use of Starters
In the Ossau area of the Pyrenees, a visit to one of the area's traditional affineurs and champions of the region's traditional sheep's milk cheese brought out an unexexpectedly strong opposition to the use of starters. The affineur, M. LaBorde, is adamant, almost vitriolic, about how the use of starters is ruining traditional cheese. It's a fast dependable method, "but it ruins the cheese." On top of all else, "starters where developed for cows milk cheeses, and aren't really suited to sheep cheese making." People start to use starters because financially they can't afford to lose cheese to inconsistency. But the starters ruin the cheese. Fortunately, he says, "three quarters of my shepherds don't use starters."
Tasting Starters
Visiting Coolea in the mountains of Co. Cork with Randoph Hodgson from Neal's Yard, I had a chance to do what few consumers can: taste and compare starter cultures. Dickie Willems has taken over the cheesemaking from his parents, Dick and Helene Willems who started making Coolea cheese in the eighties. The folks at Neals Yard had noticed some sub optimal changes in the flavor of the cheese in the last year. So in trying to isolate what could have contributed, Dickie had referred back to his log of notes made on each day's make. He'd narrowed down the possible factors until it seemed likely the problems was coming from the starters.
Now doing a starter tasting isn't something I'm recommending for you to do at home. But since hardly anyone other than cheesemakers ever does it I thought it worth sharing the story.
In truth, not having tasted a starter on its own before I was a bit wary. I imagined it might have some awful chemical flavor, but like some shy kid on the playground I was too self-conscious to say I didn't want try them, so instead I tried to act as non-chalant as I could about it. The starters come to the cheesemakers in little paper packets, sort of the same shape and size of the seed packets that you see in every gardening store. How do you taste a starter? You just open the packet and shake a little into the palm of your hand. Then you stick your tongue out and lick.
My fears were unfounded. We tried three different starters: each had a mild pleasantly sweet lactic flavor, kind of like a mellow milk flavored Lickamade. After a couple rounds of tasting and quick conferring Rand and Dickie determined that one of the starters seemed to offer a sweeter flavor, and was likely the one to go with.
The Rennet
At the same time, rennet is also added, causing the milk to curdle, separating what was originally a homegenous liquid into solid curd and liquid whey, the self-same stuff that Little Miss Muffet was munching on in the nursery rhyme. Rennet comes from the lining of the calves fourth stomach (or from lamb or goat). Who first discovered that rennet would cause milk to curdle no one knows. Legend has it that some prehistoric man or woman must have been transporting liquid milk in an animals stomach on a warm summer day. The heat, the turbulence from walking and the rennet lining acted to separate the milk into curd and whey.
These days many, many cheeses are made with what is often referred to as "vegetarian rennet." Taken literally it always strikes me that the phrase would refer to "the lining of the stomach's of young vegetarians," but of course that's just my mischevious mind working overtime. Actually, as you likely already guessed, vegetarian rennet is actually a lab-produced rennet substitute which allows for lower cost, easier access, and a cheese that is acceptable to strict vegetarians. Tom Vella, the man who started Vella Cheese earlier in the century, whose son Ig still makes some of America's all-time best cheese (Dry Jack and authentic Monterey Jack) was one of the first in this country to work with it. Vegetarian rennet has become quite common these days, and real rennet is getting harder and harder to find. In Britain no one actually makes it any more. Traditional cheesemakers who want real animal rennet have to buy from France.
The amount of rennet used varies from recipe to recipe and maker to maker. Generally softer cheeeses use smaller amounts of rennet, leaving the curd more malleable.
In some parts of Spain, Portugal and Provence, a natural "vegetarian rennet" has been used for centuries. Someone discovered centuries ago that a particular small purple thistle worked the same way as rennet, causing separation of curd and whey. Torta del Casar and Queso de la Serena are two traditional Spanish cheeses made using thistle, as are a number of excellent Portuguese cheeses, unfortunately, rarely seen in this country.
The Curd
The action of the rennet causes the curd to "set up:" it slowly solidifies, looking, well, like a big block of tofu (ever wonder why they call tofu bean curd?) The temperature of the milk is usually maintained somewhere between 70 and 95°F. Generally, lower temperatures leads to softer curd; higher temperatures to more rubbery curd. Moderate temperatures are usually the best for making the best cheeses. In total set up time takes roughly a couple of hours.
Once the curd has set up it is cut or broken in order to release the liquid whey which would otherwise be trapped inside. The cutting is accomplished with what are known as curd knives. The Swiss call them cheese harps. Wires or blades are run the length of a rectangular frame. The entire frame is passed through the curd mass, cutting it into smaller sections. The harder the cheese one is making, the smaller the curd will be cut.
In making the best fresh goat cheeses the curd is never actually cut, but rather gently broken as it is hand ladeled into small plastic or wooden molds. The process for Camembert is comparable. Commercial versions have long since abandoned this time consuming technique. But hand ladeling protects the integrity of the curd in these delicate cheeses, and makes for more flavorful, more delicately textured cheese.
During the cutting, the curd may or may not be heated, depending on the type of cheese being made. The more heat is applied the more whey will be expelled. Hence recipes for soft cheeses call for lower temperatures; hard cheeses higher ones. Some cheeses with more crumbly textures, , like Roquefort, are not heated at this stage at all.
Regardless of recipes, when the proper texture is attained, stirring stops and curd is allowed to settle to the bottom of the vat.
Draining The Whey
When the right moment arrives (different for different cheeses) the whey is drained off from the curd. Many traditional dairy regions make a cheese from the whey, the most famous of which is probably ricotta. By re-heating the drained whey, whey solids can be separated and then gathered from the liquid whey. Whey cheeses are often eaten fresh, but can also be aged; ricotta salata from Italy and Gjetost from Norway (made from goat's whey) come to mind. Some cheesemakers will make whey butter from the bits of curd remaining in the liquid whey.
Additionally, whey may be fed to pigs; in Parma the whey from the area's famous cheese is a key component of the diet of the pigs that later become Prosciutto di Parma. Sprayed onto fields in limited quantities whey will also serve as an effective natural fertilizer. Whey is also used in large quantities commercially to make whey powder, which you'll see on many processed foods. Whey disposal can be a big problem it can be a serious pollutant if released into rivers because of its high acid makeup.
Setting Up of the Curd
Once the whey has been removed, the new curd is allowed to rest, or, "set up." During this stage, acidity rises and the bacteria multiply, all acting to develop the flavor of the cheese in progress. Although different cheese recipes have their various nuances throughout the making, at this point in the process recipes really diverge. For example:
- Blue cheeses aren't cooked at all so that the curd stays loose, allowing in air which will activate the all important mold growth.
- In making Swiss type cheeses, the curd and whey are heated together to about 120°F. This seriously alters the texture of the curd, creating the smooth, slightly rubbery, texture we associate with Swiss cheeses. Later the curd is revoved from the liquid whey, left behind to make whey cheese.
- To make mozzarella or other pasta filata cheeses like Provolone, the maker takes drained curd, then heats it to allow the curd to be kneaded and stretched much like bread dough. The results are known as "pulled curd" cheeses. Mozzarella would be eaten fresh; Provolone put up to age for a few months on up to a few years.
- Cheddaring cuts the curds into rectangular shapes, then piles the curds curd bricks, allowing them to knit together; the natural weight of the blocks one piled on the next expels additional whey and makes for a more closely textured cheese.
Additionally some recipes require that the curd be milled to make it even finer and expel even more whey. Cheddars and Cheshire come to mind.
Pressing
The curd may be pressed at this stage. The more the curd is pressed, the more whey will be expelled, the firmer the texture of the finished cheese will be. For example, finely textured Cheddars are pressed for up to a three days; the more crumbly Cheshire for only 24 hours.
At the end of this process the curd is removed from the vat and put into molds, or forms, which will give its characteristic shape. In days past forms where made of wood, today more often than not, of plastic or stainless steel.
Salting
Somewhere along the line in the cheesemaking salt is added. Poor salting can make for a very poor cheese, in spite of what might have been excellent milk. Too little salt usually means too much moisture, poor (rapid) ripening, poor flavor development. Too much salt creates a dry, salty, very slow maturing cheese.
Salt serves three primary purposes in cheesemaking:
a) It adds to the flavor of the finished cheese. Without it the curd will most certainly be bland.
b) It removes additional moisture from the curd.
c) It slows-but doesn't stop-bacterial activity in the cheese.
There are four main methods of adding salt:
1) It may be added right to curd (e.g., Cheddar)
2) It may be done by brining the young cheeses (as is the case with Gruyere, Emmental and Parmigiano Reggiano).
3) Alternatively the rind may be rubbed with coarse salt (this is done with Comte and Roquefort).
4) Washed rind cheeses are rubbed with brine which may contain other ingredients in addition to salt.
The latter two techniques helps to enhance rind development as well. In all three of the latter scenarios, salt is pulled into the interior of the cheese and moisture is pulled out through the porcess of osmosis.
Maturing/Ripening
Once the cheese has finished draining, and/or brining, its final form has been basically determined. From there, the process of maturing begins. For fresh cheeses, this may last a matter of mere days, or even just hours. For long aged cheeses it may go on for months or even years. During the maturing process, microbes in the cheese slowly changing its texture and flavor. Each cheese has its own "recipe" for maturing, and even within that each affineur (or cheese ager) will have his or her own style. In general maturing takes place in conditions of relatively high moisture usually at least 80 percent, but often up into the high nineties. Maturing temperatures range from 50 to 60 ° F, depending on the cheese. To slow maturing colder temperatures will help. Soft cheeses have higher moisture levels and, hence, more hospitable hosts for bacteria; often they are matured at cooler temperatures to avoid risk of rapid overripening.
Proper maturing is-after the role of starters-another of the "secrets" of great cheeses. Yet it is often overlooked in this country. A matter of months (or sometimes more) in an affineur's cave does for fine cheese what a few years in a wine cellar will do for a well-made wine. On the other hand, most industrially made cheese is sealed in plastic early on, then stored at very cold temperatures to prevent mold growth and moisture loss (aka, cost), in which case "maturing" really doesn't matter. But well made cheese, properly matured by a master is something special.