My first impression of Sister Noella was of a woman decidedly more earthy than spiritual. But I soon came to see that, for her, the miracles of Christ were many, and could be witnessed in the unlikeliest of places, including in a barrel of milk or under a microscope. Several of Christ's miracles rather famously involve fermentation, as she pointed out to me with a twinkle. Like bread and wine, cheese is the transformation of ordinary matter into something extraordinary, a process suggestive of transcendence.

"I never did understand why cheese wasn't included in the Eucharist," she told me at one point. At first I thought she was joking, but she turned serious. As a sacrament, Sister Noella suggested, cheese would actually offer something that wine or bread cannot. "Cheese forces you to contemplate death, and confronting our mortality is a necessary part of spiritual growth."

I knew enough to know Sister Noella wasn't referring to the mortal risk of food poisoning, but what exactly she was referring to with this comment, clearly heartfelt, it would take me some time in the cheese-making room, and the cave, to figure out.

Learning how to make cheese from Sister Noella, rather than another of America's rapidly growing tribe of artisa.n.a.l cheese makers, has its advantages and disadvantages. On the positive side, her method and approach are so Old World that they reveal the process at its most stripped down and elemental. Not only does Sister Noella have no use for pasteurization or stainless steel, but she relies exclusively on naturally occurring bacteria and fungi-she adds no commercial cultures, which is virtually unheard of in modern cheese making. That brings me to one of the disadvantages of learning from Sister Noella: Her approach is so far outside of the mainstream that it is in no way representative of how most cheese is made today, even artisa.n.a.l cheese. Yet there is one other, crucial advantage: Whereas most of the cheese makers I visited and interviewed would only let me watch them work, and then only after walking through a vale of disinfectant and donning a virtual hazmat suit, Sister Noella was perfectly happy to let me get my hands wet and to handle the curd.

The work of making cheese at the abbey is carefully st.i.tched into the daily rhythms of the place, which revolve around worship, seven times a day and once in the middle of the night. After Lauds at 6:00 a.m., the abbey's five cows are milked, and the milk is carried, still warm, to the cheese room, where it is poured into the wooden barrel. Right before eight o'clock ma.s.s, Sister Noella adds two tiny vials of rennet to initiate the coagulation of the milk. While she and her sisters are at ma.s.s, singing Gregorian chants and taking communion, a complex biochemical alchemy begins to unfold in the big barrel.

Lactobacilli present in the raw milk and the surface of the wooden barrel begin furiously to reproduce, gobbling up lactose and converting it into lactic acid. The pH of the milk gradually falls, and as it does, the milk becomes inhospitable to undesirable strains of bacteria, including any E. coli that may have found their way into it. The acidifying environment also promotes the action of the rennet, which begins magically to transform the fluid milk into a silky white gel. Returning from ma.s.s at ten-thirty, Sister Noella ran her index finger through the surface, cleaving open a little canyon where, just an hour or two before, there had been only liquid. It looked like a soft tofu, but it gleamed. For most of the cheese makers I've met, Sister Noella included, this is the moment of magic.

Rennet, the catalyst of this alchemy, is stuff so strange as to be almost mythological. Ripped from the belly of a baby animal: And so it is, literally. Rennet comes from the lining of the first stomach of a calf, lamb, or baby goat. It contains an enzyme called chymosin, the function of which in a baby's stomach is to curdle mother's milk, thereby slowing its absorption and rearranging the milk proteins in such ways as to aid the baby's digestion. Anyone who has ever burped a baby and been spit up on for his troubles, has observed the action of chymosin on milk.

Presumably some herder discovered the process several thousand years ago, when he or she slaughtered a young ruminant, opened up its stomach, and found some lumpy curds of milk. Or perhaps the ancient herder used the stomach of a young animal as a vessel in which to store or carry milk. Exposed to the rennet in the stomach lining, the milk would have turned to something much like cheese. Whatever its taste, the advantages of this "processed" milk over fresh would have been immediately apparent, particularly to a nomadic people in a time before refrigeration. Since curdling removes most of the water from the milk, it renders the food much more portable, and the curds, having been acidified in the animal's stomach, would remain edible much longer than fresh milk.

What this suggests is that cheese was not so much an invention as a discovery. Like other fermentations, cheese making is a form of "biomimicry"-a technology modeled on a naturally occurring biological process. Certainly there was plenty of room for improving on stomach-curdled milk, including its taste and appearance and longevity. But, like other fermentations, cheese was from the beginning a boon to humankind: a perishable foodstuff that has been processed in such a way as to render it more digestible, more nutritious, more durable, and more flavorful than the original.

Rennet, which, remarkably, still often comes from the stomach linings of baby animals,* requires an acidic environment in order to best perform its magic of coagulation. In cheese making, the acid is supplied by bacterial fermentation rather than stomach acids. As in pickles and sauerkraut, the necessary bacteria are ubiquitous in the environment and on the "substrate"-in this case, the raw milk. But pasteurizing milk creates a biologically blank slate, into which cultures of lactobacilli must be reintroduced after pasteurization in order to acidify the milk and begin to build flavors. Starting with a clean slate has its advantages: The cheese maker can decide precisely which bacteria to introduce, and there will be few surprises-or "accidents de fromages," as the French call their cheese-making disasters. That's why such blank-slate ferments are now the rule, and not only in cheese-making. Most brewers and winemakers work the same way, killing off the native bacteria and yeasts and then reintroducing only the ones they want. Yet the gain in control of the process comes at the price of a loss in complexity that, according to proponents of raw-milk cheeses and other wild fermentations, you can taste.

One of the things you can taste in a raw-milk cheese is the taste of a particular place. For her dissertation research, Sister Noella drove around the French countryside, collecting samples of the microbes living on the rinds of various raw-milk cheeses. She focused her attention on Geotrichum candidum, a fungus I had never heard of but, it turns out, I have been eating large quant.i.ties of all my life: It is the mold that forms the downy white jacket on fungal-ripened cheeses like Camembert and Brie. (The French call it the jolie robe-"pretty dress.") Using genetic-sequencing techniques to compare her samples, Sister Noella found "an enormous diversity" among strains of geotrichum. She also discovered that different strains of the same mold feasted on different nutrients in the milk, producing different chemical by-products that contribute different flavors to a cheese. She concluded that at least some part of the astounding diversity of French cheeses-"How can anyone be expected to govern a country with 246 cheeses?" Charles de Gaulle once famously asked-owes to the wide diversity of its microbes.

What this suggests is that terroir-the French term for the taste of place-is influenced not just by the local climate or soil but also by differences in the local bacteria and fungi. Sister Noella has come to think of this microbial biodiversity as part of a nation's patrimony. "People understand the importance of preserving an endangered white rhino," she told me. "But a strain of fungus no one has ever seen or even heard of is a tougher sell"-yet in her view no less important. As Italo Calvino wrote in Palomar:

Behind every cheese there is a pasture of a different green under a different sky: meadows encrusted with salt that the tides of Normandy deposit every evening; meadows perfumed with aromas in the windy sunlight of Provence; there are different herds, with their shelters and their movements across the countryside; there are secret methods handed down over the centuries. This [cheese] shop is a museum: ... behind every displayed object the presence of the civilization that gave it form and takes form from it.Later that afternoon, in her little laboratory on the abbey grounds, Sister Noella elaborated on the elusive concept of terroir. The particular taste of a place, as she conceives it, owes to a tight weave of natural and cultural threads that cannot readily be teased apart. Clearly the qualities of the milk (What breed were the cows? What plants grew in the pasture they grazed? What was the weather like?*) influence the flavor of a cheese, but so does even the tiniest detail in the technique of the cheese maker. And though we would tend to regard such details as artifacts of human culture rather than nature, their influence on the flavor of a cheese is mediated by microbes-that is, by nature. So, for example, the temperature in the vat; the time between steps; the tools used to cut the curd; the geometry of the molds into which they were pressed; how hard they are pressed; how much salt is introduced; the humidity in the cave; even the type of straw on which the cheeses rest as they age-all these details help to determine precisely which microbes will predominate, and these in turn help determine the sensory qualities of the finished cheese. (The rye straw? Sister Noella explained that rye gra.s.s favors the growth of Trichothecium roseum, "the flower of the molds"-lending a pinkish cast to the rind that is prized by the French.)

"A cheese is an ecological system," Sister Noella explained, "and the cheese maker's techniques operate like forces of natural selection to determine which species will succeed"-thereby creating the specific flavors and aromas and texture of a Saint-Nectaire rather than, say, a Mont d'Or or Reblochon. In this, a cheese is much like a sourdough bread culture, except that its microbial community is even more complex and long-lived. Indeed, it is still living when we eat it, whereas the culture in a bread dies in the oven.

When Lydie returned to the abbey two years after teaching Sister Noella to make cheese, she was astonished to find that the rind of a Connecticut Saint-Nectaire had developed the very same fungi as a Saint-Nectaire ripened in the Auvergne-up to and including the Trichothecium roseum. So was it possible Lydie had unwittingly carried those French microbes on her person during her first visit? Not likely, according to Sister Noella.

"Everything is everywhere," she explains, referring to the numberless species of fungi and bacteria ubiquitous in the environment, "and then our technology selects" which among them will thrive. But wouldn't this selection-by-culture argue against the idea of terroir? Only if your concept of terroir is limited to the local expression of nature. Yet a place is much more than a patch of earth; it is also the people who live in it and the traditions they follow, and so in turn the microbes they unconsciously favor-and which in turn have favored them, with desirable flavors and aromas. These highly particular qualities (which seem to be found in fermented foods especially*) owe at least partly to the reciprocal relationship of microbe and man-nature and culture together, as expressed through fermentation. So along with all the other elements contributing to the particular taste of a place-soil, climate, flora, tradition, technique, story-we need to add one more: the microbiology of human desire.

After Sister Noella had satisfied herself that the milk was sufficiently coagulated, she invited me to run my fingers through the pristine white Jell-O, gently breaking it up into tinier and tinier curds. I worked alongside the abbey's newest postulant, Stephanie Ca.s.sidy. A willowy thirty-year-old with big brown eyes, Stephanie took care of the abbey's cows and had recently begun helping out with the cheese making. Bending over the barrel from opposite sides, we ran our hands through the warm curd, carefully subdividing it into little white peas. The recipe specifies that the curd be kept at the same temperature as the cow's body, so from time to time Sister Noella poured a little hot water along the inside edges of the barrel to keep it from cooling. When Stephanie judged the curds uniformly tiny enough, she took the wooden paddle from its nail and, running it slowly along the side of the barrel, began to herd the little curds together.

They seemed to like one another's company. That's because the chymosin in the rennet had snipped off a specific bit of one of the casein proteins that, in fresh milk, functions like a b.u.mper to keep the particles bouncing off one another and so dispersed in solution. The milk coagulates when the now b.u.mperless casein proteins bond to form a kind of mesh that traps fat and water. The goal in handling the curds is to gently expel the water from them while losing as little of the fat as possible.

The curds tasted sweet and clean but bland, more like fresh warm milk than cheese. But their blandness gave no hint of the frenzy of activity going on deep within them, as the curds formed and re-formed. Virtually all of the microbial DNA necessary to create a mature cheese was now present and accounted for and beginning to do its fermentative work. The lactobacilli were proliferating wildly in the warm milk, turning the lactose into lactic acid, contributing flavors, and lowering the pH, a souring process I could faintly smell. The acidification would continue in the cheese for several weeks before reversing course, as the fungi-also already present in the milk, as spores-took over, inaugurating a second fermentation in the rind. But I'm getting ahead of myself and the microbes. ...

Once the wooden paddle had persuaded the curdlets to come together in a casual ma.s.s, Stephanie began removing the whey from the barrel with a flat-bottomed pan. Then, with the palms of her hands, she began pushing the ma.s.s of curd down toward the bottom of the barrel. I joined her, leaning over the barrel and pressing the curd down as slowly and gently as I possibly could, so as not to disturb the precious b.u.t.terfat.

"Restez la," Sister Noella implored us as we worked, explaining that that is what Lydie's mother used to tell her whenever she had her hands on the curd. "Stay there"-move your hands as little and as gently as possible. Impatience would be ruinous; by forcing out the fat, it would make the paste-the interior of the cheese-rubbery. (Thus does the mood of the cheese maker find its way into a cheese.) The muscles in my wrists and lower back had begun to howl, but I kept at it, pressing down as slowly and deliberately as I could bear to. After decades of doing this kind of work several times a week, Sister Noella has had to have several surgeries to repair the carpal tunnel in her wrists.

At last Sister Noella p.r.o.nounced herself satisfied with the curd. It now formed a three-inch-thick layer at the bottom of the barrel, snowy white beneath a few remaining inches of yellowish, sour whey. Standing up straight had never felt so wonderful. Alas, it was not to be for long. The time had come to cut the curd, and Stephanie handed me a long knife. She had me cut it in thirds, first top to bottom and then side to side. Then, with our hands, we scooped up the white bricks and piled them into the molds. Cylindrical containers the size of deep pie tins, the molds are made of wood or white plastic with a pattern of holes drilled into their bottoms. Now came more urgings to "restez la" as I slowly pressed the blocks of curd into the molds, turning them over from time to time. A thin trickle of whey wept from the holes. The curds were now tightly knit into something that looked and felt like a cheese, except that it was completely white and tasteless. We sprinkled some salt on the exposed side.

The term for these fresh discs is a "green cheese" and, incredibly, we had made only three of them from nearly fifty gallons of milk. Now, stacked one on top of another, the cheeses went into the press, an old wooden contraption with a big steel screw that could be manually tightened to gradually build pressure, squeezing still more water from the cheeses. We were done. The green cheeses would spend the night in the press, weeping their last few tears of whey, before being rinsed and moved into the "cave" the following morning. Here, they would spend the next two months, growing old.

Cheese is milk that has grown up. ... It is preeminently the food of man-the older it grows the more manly it becomes, and in the last stages of senility it almost requires a room to itself. -Edward Bunyard (18781939), The Epicure's CompanionCompared with other fermentations-of vegetables, grains, or grapes-the fermentation of fresh milk into a mature cheese depends on a remarkably complex dance of taxonomically far-flung species, including mammals, bacteria, and fungi. Or perhaps I should say fermentations, plural, because what takes place in the aging room is so different from what happens in the milk vat as to const.i.tute a whole other order of transformation.

Most of the activity in the vat involves anaerobic bacteria turning lactose into lactic acids; that process continues in the paste-the airless interior of the cheese-with some elaborations, as enzymes produced by the bacteria break down fats, proteins, and sugars into simpler and generally more flavorful molecules. But as soon as the cheese maker forms the curds into, well, forms, she has created something new: an inside, the paste, and an outside, the incipient rind. Biologically, the rind comprises a new environment-airy and moist, but no longer wet-which selects for a new set of microbes: the aerobes. The spores of these aerobic microbes are already present (everything is everywhere) in the milk, in the air, clinging to the stone walls and earthen floor of the cave. And so, within hours, this new cast of microbial characters, beginning with a group of acid- and air-loving fungi, begins to colonize the wide-open frontier of the cheese rind.

Standing in the abbey's "cave," it is possible to observe this succession of species as if in time lapse. The cave is really just a ten-foot-square corner of a cellar, walled off and air-conditioned to maintain cavelike temperatures and levels of humidity all year long. Lining the walls are tall wooden cabinets faced with screen doors. Their shelves hold two months' production of cheeses, arranged according to seniority. Written on the side of each cheese in blue ink is the date on which it was made and the initials of its maker. Starting with the fat white discs made yesterday, I could follow the cheeses' progression from callow youth to venerable age, as the bloomy white rinds gradually take on some gray, then slowly mottle and shrink, until you arrive at the wrinkled and stinky gray-brown visage of a Saint-Nectaire that, after two months, is fully ripe and ready to eat.

What takes place in the rind over the course of these eight weeks is a more or less orderly form of rot. As successive rounds of decomposition unfold, one species dines on the waste products of another, in the process creating the conditions, and often the food, for the next. Most of these fungi you know well and have had reason to despise in the past: They are the same molds that turn white bread blue, that establish furry white beachheads on a ripe tomato or draw a dilating brown target on a pear. The cheese maker has learned, at least to an extent, how to manage or guide these familiar wild species, getting them to behave in more or less predictable ways.

Sister Noella walked me through the stages of fungal life and death unfolding in her cave. By the second day, a fine lawn of yeasts-primarily Debaryomyces and Torulopsis-has spread across the fresh cheese, though it is only visible through a microscope. There are also invisible colonies of bacteria, such as Streptococcus cremoris, working to turn the lactose in the milk into lactic acid-food for future fungi. By the sixth day, the cheese has grown a fine white beard of hyphae from a fungus called Mucor. This particular fungus, which the French sometimes call the bete noire, is considered a catastrophe when it appears in a Brie or Camembert, but is warmly welcomed in a Saint-Nectaire or Tomme de Savoie. When on day nine the Mucur sporulates, a field of what (under the microscope) looks like black daisy seed heads colonizes the rind, transforming its pristine white to a grayish brown. By now the cheese looks as though it has lost its youthful innocence and acquired a few unsightly scars of experience. It has also visibly shrunk, as the water in it continues to evaporate.

In the shade of those blackish Mucor hyphae, strains of Geotrichum candidum, Sister Noella's favorite fungus, are feasting on lactic acid and growing their own hyphae, though they are not yet visible to the naked eye. "Geo," as some American cheese makers call it for short, is responsible for the downy white coat-the jolie robe-found on a Saint-Marcellin. The fungus introduces a set of powerful enzymes that break down various fats and proteins, in the process helping to develop the cheese's flavor and releasing several strongly aromatic compounds, including the faint whiff of ammonia that filled the cave. Sister Noella has ultimate respect for Geotrichum, which was the subject of her dissertation. She mentioned that its enzymes have been known to bore holes through plastic. Some strains of Geo also seem to make it more difficult for Listeria to survive in a cheese.

By breaking down lactic acid and producing ammonia, Geotrichum neutralizes the pH of the rind, changing the environment in such a way as to make it hospitable to subsequent waves of bacteria and fungi. By sending its filamentous hyphae down into the paste, the fungus in effect "tills" the rind of the cheese, digging microscopic channels that allow other aerobic microbes, like Penicillium, to move deeper into the cheese, contributing new flavors and aromas. These penetrations gradually thicken the rind and multiply its population of microbes, both in number and in kind. Soon the rind acc.u.mulates a grayish dust of "fungal debris"-spores and the bodies of dead fungi-that gives off the musty odor of a dank, neglected cellar. By day thirteen pinkish patches of Trichothecium roseum have begun to powder the rind, giving a violet cast to the Saint-Nectaire. By now the pH of the rind has been neutralized, creating a happy habitat for coryneform bacteria such as Brevibacterium, which eventually will contribute powerful aromas to the ripening cheese.

And so it goes for the two months it takes a Saint-Nectaire to ripen, each species altering the rind environs in such a way as to pave the way for the next, in a predictable ecological succession that Sister Noella carefully doc.u.mented in her dissertation. Along the way, each species releases its own set of enzymes, each one a customized molecular tool for breaking down a specific fat or sugar or protein into an amino acid or peptide or ester that contributes a specific flavor or aroma to the ripening cheese. Within a few weeks, the process of ecological succession has culminated in the establishment of a fairly stable community of fungi and bacteria. Much about this microbial community remains a wilderness to science. But Sister Noella is in touch with a group of microbiologists who are actively exploring the cheese-rind ecosystem, hoping to learn how the various species compete and cooperate, and how they may communicate with one another to defend their turf (and in turn the cheese beneath it) from invasion, in a process known as "quorum sensing."

Listening to Sister Noella exalt this leprous skin of decomposed milk as a vibrant ecological community is to appreciate just what a weird and wonderful achievement cheese is: how our ancestors figured out how to guide the decomposition of milk so that it might be arrested and then defended, using a jujitsu move that deftly deploys rot against rot, fungus against fungus, to suspend milk's inexorable slide into putrefaction just long enough for us to enjoy a tasty cheese. Other ferments operate on the same general principle, earth to earth deferred, but, unlike wine or beer or a pickled beet, the aroma of a ripened cheese won't ever let us forget the role rot has played in its creation.

Over time, the fungi living and dying in a cheese rind work to neutralize their environment, a development that hastens the ripening of the cheese in two important ways. First, the difference in pH between the paste and the rind creates a "gradient," or imbalance, that serves to draw the strong-smelling compounds produced on the rind deep into the paste; ripening from the outside in, the cheese is bland no longer. At the same time, the rising pH of the rind creates conditions much to the liking of a notorious microbe called Brevibacterium linens, the appearance of which, beginning around week three, is marked by a distinct reddish-orange cast creeping over the rind. But you don't need to see B. linens to know it has arrived: B. linens is the bacterium responsible for much of the stink in a stinky cheese. Along with a few other members of its bacterial family, the coryneforms, B. linens is the reason certain ripe cheeses need a room of their own.

Saint-Nectaire is home to a healthy population of B. linens that, when the cheese is fully ripe, gives it its distinctive barnyard smell. But it is in the washed-rind cheeses-epoisse, Limburger, Taleggio, and, in America, newer ones like Red Hawk or Winnimere-where B. linens is actively encouraged to flourish, imbuing these cheeses with their powerful and occasionally room-clearing aromas. Washing the rind, usually with salty water (sometimes with wine or beer), creates an environment maximally hospitable to B. linens, which in turn can single-handedly create an environment that is either much more or much less hospitable to members of our species. Some people love the smell of B. linens, or learn to; others find it revolting. And still others are repelled and attracted to it at the same time, captivated by what might be called the erotics of disgust.

"Oh, I really like that term," Sister Noella said, when I raised, as delicately as I could, the issue of rankness in her cheese. The subject of disgust is not something I've found many cheese makers eager to discuss, at least not in the company of journalists. But Sister Noella is happy to talk about the earthier dimension of her work, at least up to a point.

"Cheese is all about the dark side of life," she said one afternoon as we were strolling up the hill to her lab. She told me about a French cheese maker of her acquaintance, a monk by the name of Frere Nathanael, who makes a strong cheese called Tamie at his monastery in the Haute-Savoie. She once asked him how he determined when a Tamie is ripe. You turn it over and sniff the bottom, Frere Nathaniael told her. "ca sent la vache." It's ready when it smells like the cow. And then, in case that wasn't quite clear enough, he added, "The back end of the cow!"

It suddenly dawned on me that "barnyardy"-a term cheese mongers use in praise of certain stinky cheeses-is a euphemism for manure. (Duh!) Certainly the manure of some farm animals, such as cows, is not unappealing, at least when they've been out grazing on pasture. Yet some cheeses make even less socially acceptable allusions, if that's the right word. The various aromas of washed-rind cheeses are often likened to those of the human body in its various parts. A French poet famously referred to the aroma of certain cheeses as the "pieds de Dieu"-the feet of G.o.d. Just to be clear: foot odor of a particularly exalted quality, but still-foot odor.

Sister Noella told me about another cheese-maker friend of hers, James Stillwaggon, an American living in France, who holds unusually frank views on the subject of cheese olfaction. She had recently quoted him at the end of the draft of an article on the microbiology of cheese rinds, though she wasn't sure if his remarks would survive editing. The quote came from an exchange the two had had on the question of why the vocabulary used to describe wine is so much richer and more nuanced than the vocabulary used to describe cheese. Wine talk is full of vivid metaphor-comparing wines to specific fruits and flowers, for example-whereas, as Stillwaggon pointed out, the flavors of cheese usually elicit only vague, generalized comments "like 'Mmmm, good!' 'Interesting!' 'Fantastic!'

"If we address frankly what is evoked by cheese, I think it becomes clear why so little is said. So what does cheese evoke? Damp dark cellars, molds, mildews and mushrooms galore, dirty laundry and high school locker rooms, digestive processes and visceral fermentations, he-goats which do not remind of Chanel ... In sum, cheese reminds of dubious, even unsavory places, both in nature and in our own organisms. And yet we love it."

In its very suggestiveness, cheese is both like and unlike many of the other foods humans cook or ferment. Whether by fire or water or the action of microbes, one of the ways humans transform the edible stuff of nature is in the direction of greater allusiveness-in taste or smell or appearance. Just as we take pleasure in enriching our language with layers of metaphor and allusion, we apparently like to trope what we eat and drink, too, extracting from it not only more nourishment but more meaning as well-more psychic nourishment, if you will. It just so happens that the more vivid, odiferous tropes that cheese makers have teased out of milk can verge on the indecent, taking us places polite society doesn't like to go.

But the question arises: Why would we want to go there in the first place? Why don't cheese makers stop with the sweet, freshly showered scent of mozzarella, rather than press on to the ripe raw-milk Camembert with its suggestions of, well, negligent hygiene?

Compared with some other mammals, we humans have long been alienated from our sense of smell. From the moment we began to walk upright, the eye took precedence over the nose. This, at least, is Sigmund Freud's theory for why humans have repressed so much of the sensory data supplied by the nose, and why our vocabulary for describing smells is comparatively so thin and generalized. (Mmmm, good!) The smells we are repressing are of course those of the lower body and the earth, which walking upright allows us to transcend, or at least overlook, in humanity's age-old top-priority project of putting s.p.a.ce between itself and all the other animals. But that project has a cost. The reason those smells so transfix mammals that still walk on four legs is that they contain deeply compelling information, information the high-minded biped is missing. Freud never said this, but Stillwaggon conceivably might: A strong cheese puts us back on all fours.

Metaphorically speaking, of course. Or maybe not. Because one of the most curious things I learned about the bacteria that give cheese their aromas is that they are, at least in some cases, closely related to the bacteria that give us our aromas. Brevibacterium? It not only lives in the salty damp of a washed-rind cheese, but is equally at home in the salty damp under human arms or between human toes. (I give you "the feet of G.o.d.") Sweat by itself has no discernible odor; what you think you smell when you smell sweat are the metabolic by-products of brevibacteria, as they busily go about fermenting, well, you. And your toes and armpits are not the only bodily zones where such fermentations are taking place, either.* So it may well be that the allusiveness of a funky cheese to the human body is actually more literal than metaphoric, a matter not so much this stands for that as this is that, too, in food form. What's going on in certain cheeses doesn't just remind us of the body; in some sense it is the body, or at least the fermentations unfolding thereon and -in.

As you might expect, the French are much more comfortable with these ideas, and these cheeses, than Americans seem to be. In fact, some Frenchmen regard America's uneasiness with raw-milk cheeses (which tend to be more odiferous than cheeses made from pasteurized milk) as further proof of our puritanism in carnal matters. Pierre Boisard, a French sociologist, celebrates a raw-milk Camembert as "a living substance produced by an animal organism, [that] constantly reminds us of the body, of sensual pleasure, of s.e.xual fulfillment, and of all that is forbidden in it." Only "hidden Puritanism re-entering through the backdoor [of] alimentary hygiene"-and not the threat from listeria, say, or salmonella-could possibly explain the American government's ban on raw-milk Camembert.*

No, I never did float this theory to Sister Noella. Didn't get the chance. ... Okay, actually I could never figure out quite how to broach it. How do you ask a nun whether she believes the government's crackdown on raw-milk cheese is rooted in s.e.xual repression?

Though I did ask her, before leaving the abbey, if she could put me in touch with her friend Jim Stillwaggon, or refer me to any of his writings. She had described him as a philosopher as well as a cheese maker. Had he published any of his reflections on s.e.x and death in cheese? Did he have a Web site, perhaps?

"No, and it's probably just as well. I'm just not sure the world is ready for Jim."

On my drive home, a fragrant chunk of Sister's Noella's ripe Saint-Nectaire warming on the seat beside me, I wondered if the French might be right, and if the disgust we sometimes register at the smell of a strong cheese is the product of s.e.xual repression-a taboo at work. It does seem to be the case that the smells of cheese are ripe with the smells of the body, human or animal. Yet not all of those smells are necessarily s.e.xual in nature. When we consider "the body," certainly there is s.e.x to consider, but isn't there also death? I also wondered if maybe, on the theory (contra Freud) that sometimes a cigar is just a cigar, disgust is sometimes just disgust.

When I got home I began to dig around in the literature of disgust, which in the last several decades has attracted a handful of interesting thinkers from a wide range of disciplines, including psychology (Paul Rozin), philosophy (Aurel Kolnai), even law (William Ian Miller). Disgust, I learned, is one of the primary human emotions; it appears on even the shortest list of human emotions, and in fact is unique to our species. (Though you do have to wonder, how can we be so sure?) Darwin, who wrote about disgust in his 1872 book, The Expression of the Emotions in Man and Animals, described it as a reaction to something that offends our sense of taste (the word comes from the Middle French desgouster, or "distaste"), rooted in the biological imperative to reject foods that might be dangerous.

Building on Darwin, Paul Rozin writes that the emotion of disgust originates in "the revulsion at the prospect of oral incorporation of an offensive object." Disgust is thus a crucial tool for an omnivore at constant risk of ingesting toxic substances. But the emotion of disgust has since been co-opted by other, higher human faculties, such as morality, so that we are disgusted by certain kinds of morally offensive behavior. Rozin writes, "A mechanism for avoiding harm to the body became a mechanism for avoiding harm to the soul."