We're very excited to welcome Bronwen and Francis Percival back to the virtual pages of Serious Eats. Earlier this month, we spoke with them about their love of cheese and their new book, Reinventing the Wheel: Milk, Microbes, and the Fight for Real Cheese. As promised, the Percivals have returned to talk about one of their favorite examples of "real cheese," Kirkham's Lancashire, and how it compares to a much better-known cousin.
When you order cheddar at a deli or ask for Swiss cheese on a sandwich, you have a specific flavor in mind. All of us have expectations for how certain cheeses will taste. But even some of us within the cheese industry are often uncertain about why certain cheeses taste the way they do, and what those flavors tell us about how those cheeses were produced—and that's unfortunate. Cheese is, we would argue, the single agricultural product with the greatest ability to communicate, through its flavor, the decisions and values of the producer, whether that's a large factory or a small farmer using his or her own milk.
In either case, consumers can easily be taught to taste the difference between cheeses made with good milk, using minimal external inputs, and cheeses made with "dead milk"—milk that has been stripped of its microbial character. Once you are able to taste that difference, you can make an informed choice to pursue the flavors produced by farmhouse cheesemakers or those made in factories.
Cheddar: The Crowd-Pleaser
Our earlier reference to cheddar was no accident. (Neither was the reference to Swiss, but an explanation of that will have to wait until our next article.) Cheese made in the style of cheddar, which originated in the southwest of England, is incredibly popular; it constituted over a quarter of US cheese production in 2016. Considering that it's such a commercial behemoth, the legal definition of cheddar in the United States is surprisingly vague, essentially requiring that the cheese possess "cheddar-like" physical and chemical properties, such as a maximum moisture content of 39%. With cheddar, as with pornography, the consumer is meant to know it when they see it.
From our perspective in the UK, this seems odd. Returned to the context of its origins, cheddar is not a sui generis powerhouse, but only the most successful member of a broad family of regional English cheeses, which also includes Wensleydale, Cheshire, and Stilton.
It is helpful to think of cheddar's ubiquity as the endpoint of an evolutionary contest, one that has gone on since the 18th century, when British cheeses began to be shipped widely and sold outside their regions of origin. If we want to understand the meaning of the flavor and texture of cheddar, and how and why it tastes as it does, we need to explore its evolutionary context. To understand cheddar, we must first compare it with its cousin Lancashire, and fully appreciate how the processes behind both cheeses link them together, even as they produce significant differences in flavor and texture.
Kirkham's Lancashire: A Local Cheese for Local People
In contrast with cheddar, Lancashire cheese never left its native northwest England, and this failure to migrate has ultimately been catastrophic for its reproductive success. While in 1939 there were still over 200 producers of raw-milk, farmhouse Lancashire cheese, today there is only one—Kirkham's Lancashire, a cheese coelacanth, a living fossil.
Yet at its best, this cheese is extraordinary: giant, 44-pound bundles of curd that Graham Kirkham, the head cheesemaker, describes as "fluffy monsters," with a pillowy, succulent texture that he likens to a "buttery crumble." The flavors, too, are deliciously round and gentle, similar to that of crème fraîche when young, and the cheese takes on a savory, brothy character and a denser, almost flaky texture with age. It doesn't provide the sweet hit of a Gouda or the smelly ooze of an Époisses, but Kirkham's Lancashire is the cheese that people who work with cheese—the jaded palates, the ones who've seen it all—eventually learn to love above all others. (In fact, it was the single cheese that we served at our wedding.) And it is an endangered species: The fate of Lancashire lies with the Kirkham family, and even they worry about its fitness for survival. Although their yearly production is equivalent to less than a day's make at a large cheese factory, they still struggle to find enough demand for all of it.
How Different Cheeses Are Made
Cheesemaking combines the bacterial fermentation of the sugars in milk with dehydration, which cheesemakers often refer to as drainage. The basic process is deceptively simple: Lactic acid bacteria—whether native to raw milk or added as part of a starter culture—digest the milk's lactose and produce lactic acid. A coagulant, rennet, is added, which sets the proteins in the milk into a gel-like curd with unique properties, specifically the ability to allow the liquid fraction to separate and drain from the milk solids, or the curd. Moisture can be removed in many ways; acidity helps the curd contract, but so does finer cutting, stirring, heating, stacking, and pressing. The range of possible combinations of these variables, as well as differences in the type of starter bacteria present, is what leads to the massive diversity of cheeses in the world today.
Rather than memorizing the specifics of a hundred cheese recipes, it is possible to understand all cheeses through the prism of just two factors: their level of moisture, and their acidity when the curd is transferred to the molds (the containers that give each finished cheese its shape and size), a step known as molding.
To help us visualize this, let's make a graph that plots moisture and acidity at the moment of molding on perpendicular axes, using X to represent the moisture level and Y for the acidity.
At the upper-right-hand corner, we find cheeses that are molded when both the acidity and the moisture are at a very high level. In the presence of acidity, the curd proteins denature and scramble to form a fragile mesh, with a lemony aroma and the texture of set yogurt. The acidity has another clever function: Its presence releases large amounts of calcium that would otherwise remain locked away in an insoluble form within the milk proteins, in the same way that eggshell submerged in vinegar eventually dissolves. The whey, which is the liquid fraction of the milk, and the soluble calcium gradually drain from the porous curd over the course of many hours. The final texture of the resulting cheeses is like a drained, partially dried version of yogurt—sour and friable. These so-called lactic cheeses are a popular choice for makers of goat's cheese, to the extent that the style of cheese itself is often referred to as chèvre (French for "goat").
Continuing clockwise around the graph, we find cheeses that result from molding high-moisture, low-acidity curds, such as soft, silky cheeses like Mont d'Or. These cheeses have a milkier, less acidic flavor than the lactic cheeses. Because the cheesemaker doesn't have to wait around for acidification to occur, and is only concerned with getting a bit of moisture out, the cheeses can be made quickly—in just enough time to set the curd, give it a cut and a few stirs, and transfer the resulting curds to the molds. As the curd never acidifies to any significant degree, the calcium is never dissolved and remains in the curd, lending it smoothness and structure.
Having covered the potential range of acidity within wet curds—which leads to the full spectrum of soft cheeses, from flaky to smooth—we are left to explore the variety of curds from which more moisture is removed during the make. Let's consider a piece of hard-yet-rubbery Alpine cheese, like Gruyère. This texture is the product of molding dry curds at a low acidity level, so they, too, retain their calcium and their strong, resilient structure. Cutting the curd into tiny pieces, adding heat, and vigorous stirring help drive off the moisture in the curd, which is molded while still bland, milky, and slightly rubbery in texture. As with the soft, smooth cheeses, these curds can be processed very quickly; most of them are made in just an hour or two, and spend the rest of their time undisturbed in the molds after the heat and action of the make.
Finally, we find ourselves at the upper left of the graph, representing cheeses for which the curds are molded at a low moisture level and a high acidity level. In the styles shown elsewhere on the graph, drainage and acidification take place at different times: first one, then the other. But here, fermentation and drainage take place simultaneously, and the two processes must be coordinated carefully. If the acidity races ahead of the drainage, the result is a weak-structured, acid curd with a tendency toward rough graininess. On the other hand, if moisture is removed too quickly, while the acidity is still too low, the result is a rubbery curd with a bland flavor. This category contains all the British territorial cheeses, from cheddar to Cheshire, from Wensleydale to Lancashire, and Stilton as well.
The profound success of cheddar as an emigrant species should not obscure its genus. As this graph demonstrates, it is absolutely not in a class by itself, but one of a whole family of cheeses as intimately related to one another as any Alpine styles. Contingency of historical circumstance is the only reason why you never face the choice of "British" or Swiss in the deli.
Modernization and a Change in Flavor
Why did cheddar win the evolutionary competition, while Lancashire has been driven to the margins? Part of the answer lies in its adaptability to being produced quickly and at large scale. Locating cheddar on our graph, we find it near the bottom of the upper-left-hand portion; it is the British cheese that leans most on fine cutting, stirring, and heating, rather than time and acidification, to drive out the moisture during its make. This means that making it is a fast and vigorous process, and one that proved amenable to modernization. A century ago, cheddar took six or seven hours to make; today some factories, by adding more starter and cutting and heating more aggressively, have brought this down to three.*
The same forces that drove cheddar toward greater speed and efficiency have ultimately left their mark upon some Lancashire cheeses as well, whose producers have chosen to add vastly more starter cultures and bend the cheesemake to an eight-hour shift. While the impact on cheddar has been to turn its flavor acid and sharp, the effect on Lancashire has been disastrous, resulting in a tough, tart-tasting cheese, its "buttery crumble" transformed into rough, sawdust-y bits of granular curd. These so-called "crumbly" Lancashires are sold cheaply in supermarkets—indistinguishable except through color from other classic British cheeses that have been put through the wringer of industrialization—and are referred to derisively as "mousetrap."
The flavor has changed as well. While 19th-century cheddar was described as "mellow in character...the flavor full and fine, approaching to that of a hazelnut," today cheddar is a cheese whose flavor is dominated by sharpness, a vestige of the large dose of acidifying bacteria needed to drive the fermentation at high speed. (These acidic or sharp flavors in cheddar, as in Lancashire, were once considered a fault, and were often associated with warm weather, when the natural proclivity of the milk to sour got ahead of the cheesemaker.) Sweet "adjunct" cultures are often added to cover the acidic and bitter quality of cheddar made in this way.
A cheese like Kirkham's Lancashire, on the other hand, is slow to make. The curds acidify over the course of a full 24 hours, leaving plenty of time for the curd to be repeatedly pressed and broken up with the hands during the day, with room for lunch, dinner, and tea breaks in between. The fact that the Kirkhams' production process never underwent any kind of modernization has meant that the cheese remains essentially unchanged from its early iterations. Slowing down the make allows them to use a tiny fraction of the starter cultures used in factory cheesemaking; Graham Kirkham's dosing is so homeopathic that he struggles to meet the minimum order requirement of the starter supplier. (Indeed, Kirkham can make his cheese entirely without added starter cultures, but feels that the starter-free cheeses are a little too soft and creamy for his liking, and prefers the lighter texture that a hint of starter brings.)
This leisurely fermentation allows the native microbes in the milk to play a much greater role in the process. Not only is the flavor produced by these microbes more intense and multifaceted, it also connects the taste of the cheese to the farm where it's made. Set up another dairy farm half a mile down the road and put that milk through the same process, and the texture would be just as mellow but the set of flavors entirely different, a tasteable expression of an entirely different microbial ecosystem.
Today, Kirkham's Lancashire sits modestly at the margins, its buttery flavor and mellow texture a quiet echo of the qualities that were prized in cheddar long ago, before factory production molded the cheese to its will. Kirkham's Lancashire is the single remaining exponent of a whole economic system, that of the thousands of farmers who once measured their day's work according to the needs of their cheese rather than brutally compressing it into an eight-hour shift. The long, slow make gives the Kirkhams the time to live their lives around their cheese. And their way of working gives us as consumers the chance to taste something rare, delicious, and illuminating.