Cooked: A Natural History of Transformation (51 page)

One of the things you can taste in a
raw-milk cheese is the taste of a particular place. For her dissertation research,
Sister Noëlla 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 quantities 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 Noëlla 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
Noëlla 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 Noëlla 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 Noëlla
explained that rye grass 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 Noëlla 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 Noëlla 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 Noëlla.

“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 Noëlla 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 Cassidy. 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 Noëlla 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 bumper to keep the
particles bouncing off one another and so dispersed in solution. The milk coagulates
when the now bumperless 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 mass, Stephanie began removing the whey from the
barrel with a flat-bottomed pan. Then, with the palms of her hands,
she began pushing the mass 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 butterfat.

“Restez là,”
Sister
Noëlla 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 Noëlla
has had to have several surgeries to repair the carpal tunnel in her wrists.

At last Sister Noëlla pronounced 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 là”
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 (1878–1939),
The Epicure’s Companion

Compared 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 constitute 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.