Cooked: A Natural History of Transformation (44 page)

Okay, but what about microbial
disease
? “To declare war on ninety-nine percent of bacteria when less
than one percent of them threaten our health makes no sense. Many of the bacteria
we’re killing are our protectors.” In fact, the twentieth-century war on
bacteria—with its profligate use of antibiotics, and routine sterilization of food—has
undermined our health by wrecking the ecology of our gut. “For the first time in
human history, it has become important to consciously replenish our microflora.”
Hence the urgency of cultural revival. And it all begins with sauerkraut, the
“gateway ferment” he had come here to empower us to make ourselves.

In modern civilization’s war on
bacteria, Sandor Katz is a conscientious objector—a pacifist. He has a remarkably
relaxed attitude toward all microbes, the ones you want in your food as well as the ones
you don’t. He’s notably relaxed about sanitation, too. “I clean my
bowls, crocks, and utensils with soapy water, but you really don’t need to
sterilize them. These practices all developed in a nonsterile world,
after all. The lactic acid will take care of it.”

He explained how this worked. The bacteria
responsible for the fermentation were wild strains of lactic acid bacteria
^*
already present on the raw vegetables, including
Leuconostoc mesenteroides,
Lactobacillus brevis,
and
Lactobacillus plantarum
. These bugs are
halophilic (salt-tolerant) anaerobes, so thrive in the airless saline niche the pickler
has created for them in the brine. They get right to work eating the sugars in the
vegetables, multiplying furiously, and releasing copious amounts of lactic acid—which
they produce for the purpose of poisoning their competitors.

Katz likened a sauerkraut to a forest
ecosystem, in which one type of bacteria succeeds another, each species transforming the
environment in such a way as to prepare the ground for the next. In a vegetable ferment,
each succeeding species is more acid tolerant than the last, until the environment
arrives at a climax stage dominated by
L. plantarum—
the great acid-loving oak
of the pickle ecosystem. All that lactic acid gives the ferment its tang as well as its
keeping qualities, since few other microbes can survive in such a low pH environment.
The idea that the safety of a food is guaranteed by the bacteria still alive in it is a
hard one for us Pasteurians to stomach. I seriously doubted I could ever sell it to my
mother.

Sandor emphasized that oxygen is the enemy
of a vegetable ferment, but should the uppermost layer of cabbage begin to rot, it is no
cause for alarm. Though it should be removed, he advised, lest the molds send their
filaments down into the kraut and reduce it to mush with their pectin- and
cellulose-destroying enzymes. Katz described digging “perfectly good”
sauerkraut out from under a layer of moldy
slime, and “off
odors” that sometimes developed during the course of fermentation, but these were
nothing to get upset about. But what if things in there got seriously funky? someone
wanted to know. Began to smell like a dead animal, say? Sandor shrugged. “You have
to trust your senses.” As he passed around little plastic cups filled with a
radish kraut he had kept in a barrel in his basement since the previous summer, I
thought about my mother, vigilantly tossing out her dented cans on suspicion of
botulism. The strong, just-this-side-of-funky smell of Sandor’s radish kraut
wafted through the store. But the kraut tasted good: still crunchy, with a bracing sour
tang.

Before there were cans, before there were
freezers and refrigerators, fermentation was the main way people preserved food from
spoiling. The very earliest fermentations were done in pits dug into the earth, lined
with leaves, and filled with various foodstuffs: vegetables, meat, fish, grain, tubers,
fruits, whatever. The earth kept the temperature low and steady and perhaps also
contributed some helpful microbes. Under these conditions a lactofermentation (that is,
a fermentation conducted by lactobacilli) would commence within days, and eventually
produce enough lactic acid to preserve the food for months, sometimes even years. In the
1980s an abandoned fermentation pit estimated to be three hundred years old was
discovered in Fiji. The breadfruit in it had been reduced to a sour mush, but it was
reported to be “still in edible condition.” (You first.)

Pit fermentation is still practiced here and
there around the world. I’ve seen whole cabbages fermenting in dirt trenches in
China, a practice also common in certain parts of Austria and Poland. The Inuit still
bury fish in the Arctic tundra, and in the South Pacific, starchy root vegetables like
cassava and taro are buried in pits lined with
banana leaves. In
Iceland not long ago, I had the dubious privilege of tasting hákarl: shark that has been
buried underground for several months, until it develops the texture and blinding
ammonia stink of an exceptionally strong cheese. What began as a practical necessity—to
get through the winter without starving—has become a cherished delicacy, at least among
Icelanders. Whenever I read that “rotten” is a culturally constructed
concept, as anthropologists tell us, I think back on my hákarl and nod in assent.

Nowadays, pit fermentation strikes most of
us as primitive, strange, and unsanitary, yet we think nothing of aging cheeses
underground, in caves, which is not so very different. And how different is a pit
fermentation, really, from fermenting food in a crock? “Earthenware,” as
it’s called, is really just earth once removed, cleaner and more portable perhaps,
but otherwise the same basic idea. Even today, Koreans bury their child-sized crocks of
kimchi in the backyard, in order to maintain the even, cool conditions that the
lactobacilli prefer. The earthenware crock is a good reminder that
every
ferment is food and drink stolen, or borrowed, from the earth, by temporarily diverting
its microbial-gravitational pull to our own ends. Everyone knows who stole the power of
fire from the gods for the benefit of humankind, but who is the Prometheus of pickling?
If mythology lacks for one, it is only because fermenting a heap of vegetables or grain
seems a less heroic mode of engaging with nature than putting a large animal onto a
fire. (There’s much less to look at, too.) But the argument can be made (and has
been, by Sandor Katz, among others) that humankind’s mastery of fermentation
rivals the control of fire in its importance to our success as a species.

If there is a culture that does not practice
some fermentation of food or drink, anthropologists have yet to discover it.
Fermentation would appear to be a cultural universal, and remains one of the most
important ways that food is processed. Even today, as much as a third
of the food in the world’s diet is produced in a process involving fermentation.
Many of these foods and drinks happen to be among the most cherished, though in many
cases the role of fermentation in creating them is not widely understood. But coffee,
chocolate, vanilla, bread, cheese, wine and beer, yogurt, ketchup and most other
condiments, vinegar, soy sauce, miso, certain teas, corned beef and pastrami, prosciutto
and salami—all depend on fermentation.

Basically, it’s all the really good
stuff.

I suspect people in other cultures feel much
the same way about their fermented foods, rotten shark included. Fermented foods are
typically both strongly flavored and strongly prized in their cultures. This suggests
that there may be a microbiology of desire at work in these foods, the bacteria and
fungi having been selected over time for their ability to produce the flavors people
find most compelling. Put another way, the microbes that could induce us to care for
their cultures, as in a long-maintained sourdough starter or cheese culture, were the
ones that prospered and survived. They travel with us through history, in a dance of
biocultural symbiosis. As with
L.
sanfranciscensis
, the bacteria found exclusively in sourdough cultures, some of
the microbial strains found in fermented foods appear to live nowhere else—those foods
have become their exclusive ecological niche. The microbes depend for their survival on
a continuing human desire for the flavors they produce—one kind of culture upholding the
other.

Ten years ago, a retired Cornell
microbiologist and fermentation expert by the name of K. H. Steinkraus conducted a
global survey of fermented food products, organized by type. Here is a very small sample
of what he found:

LACTIC-ACID
FERMENTS
: sauerkraut, olives, pickled vegetables, Chinese hum choy,
Malaysian tempoyak, Korean kimchi, Russian kefir, Indian dahi, Middle Eastern yogurts,
Egyptian laban rayeb and laban zeer, Malaysian tairu, Western cheeses, Egyptian kishk,
Greek trahanas and Turkish tarhanas, Mexican pozole, Ghanaian kenkey, Nigerian gari,
Philippine balao balao and burong dalag, sourdough bread, Sri Lankan hoppers, Indian
idli, dhokla, and khaman, Ethiopian injera, Sudanese kisra, Philippine puto, Western
sausages, and Thai nham.

ALKALINE
FERMENTS
:
Nigerian dawadawa, Ivory Coast soumbara, African iru,
ogiri, Indian kenima, Japanese natto, Thai thua nao …

On and on it goes, through the savory
amino-acid ferments (soy sauce, fish sauce, ketchup); the fermented vegetable proteins
(tempeh and ontjom); the acetic-acid ferments (vinegar, kombucha, nata de coco); and of
course the numberless alcoholic ferments practiced in almost every culture (preconquest
Australia and North America are thought to be the rule-proving exceptions), including
South American Indian chicha, Egyptian bouza, Ethiopian tej, Kenyan busaa, Chinese
lao-chao, and Japanese rice wine. To read Steinkraus’s vast exotic catalog is to
begin to appreciate the deep links between human and microbial cultural diversity, and
how through history each has fed and so sustained the other. To read him is also to
worry about the survival of this biocultural diversity, since the industrialization of
the world’s food strongly favors both homogenization and sterilization.

Important as fermentation has been to human
culture, we can’t take credit for inventing it. It is, like fire, a natural
process, nature’s primary way of breaking down organic matter and recycling
energy. Without it, as Steinkraus points out, “the earth would be a gigantic,
permanent waste dump”—the dead would pile up and there would
be
no food for the living. Humans are also not the only animal that has learned to exploit
fermentation for its own purposes: Think of the squirrel burying acorns (a kind of pit
fermentation) or the bird souring seeds in its craw. Some animals also enjoy one of the
most important by-products of fermentation: alcohol. And though few animals can be said
to actually make alcohol (though it’s been reported that monkeys in eastern China
will hoard flowers and fruits and patiently wait days for the cocktail to ferment before
imbibing), some have it prepared for them by plants. The pen-tailed tree shrew
(
Ptilocercus lowii
) of Malaysia enjoys a daily nip, drinking from a
reservoir of alcohol prepared for its enjoyment by the bertram palm (
Eugeissona
tristis
) in “specialized flower buds that harbor a fermenting yeast
community.” The palm serves wine to the shrew that, in exchange for this kindness,
pollinates the palm in the course of his barhopping through the jungle. Plant, animal,
and yeast all benefit from this clever coevolutionary arrangement.