Cooked: A Natural History of Transformation (49 page)

That, at least, is the theory. It no longer
sounds even the least bit crazy to me, but, then, maybe I’ve been spending too
much time among the fermentos, people who believe that the cure for diabetes and
whatever else that ails you is kombucha. It obviously can’t be that
simple. And yet the case for getting more live-culture foods in the
diet (especially of our children) is already compelling and growing more so. Consider
the research that has come out in just the past decade or so. Probiotics—beneficial
bacteria ingested either in fermented foods or in supplements—have been shown to: calm
the immune system and reduce inflammation;
¹
shorten the duration and
severity of colds in children;
²
relieve diarrhea
³
and irritable bowel syndrome;
⁴
reduce allergic responses,
including asthma;
⁵
stimulate the immune
response;
⁶
possibly reduce the risk of
certain cancers;
⁷
reduce anxiety;
⁸
prevent yeast infections;
⁹
diminish levels of
E.
coli
0157:H7 in cattle
¹⁰
and salmonella in
chickens;
¹¹
and improve the health and
function of the gut epithelium.
¹²

Much about the microbiota and fermented
foods remains to be explored. Scientists still don’t understand exactly
how
the probiotics in
fermented foods achieve their
effects. Only occasionally do they actually take up permanent residence in the gut. Some
of them, notably
L. plantarum
, move in and adhere to the epithelium, helping to
crowd out various pathogens and strengthen the gut wall. But other probiotic species
appear to be only transient members of the microbial community. And yet, like visitors
often do, they seem to leave their mark, contributing things of value—a useful gene or
plasmid, a bioactive chemical, some “news” of the microbial environment out
there—to the biota. Somehow, they seem to stimulate the local residents to better resist
invasion by pathogens. A series of recent papers has demonstrated that even bacteria
that are just passing through can alter the genetic expression, and sometimes the
genome, of resident gut bacteria, teaching them some new metabolic tricks.
^*

Taken together, the microflora may function
as a kind of sensory organ, bringing the body the latest information from the
environment, as well as the new tools needed to deal with it. “The bacteria in
your gut are continually reading the environment and responding,” says Joel
Kimmons, a nutrition scientist and epidemiologist at the Centers for Disease Control and
Prevention, in Atlanta. “They’re a molecular mirror of the changing world.
And because they can evolve so quickly, they help our bodies respond to changes in our
environment.”

Mysteries remain, obviously, but the case
for eating live-culture foods seems strong, and perhaps strongest for fermented
vegetables.
^†
For in addition to bringing
large numbers of probiotic guests to the party (including such impressive characters as
L. plantarum
), the
vegetables themselves also supply
plenty of prebiotics—nourishment for the bacteria already there. So you won’t be
surprised to learn I have been busy at my pickling, working to perfect my sauerkraut and
kimchi. Since they have been in the human diet for thousands of years, it makes sense
that these fermented foods would by now have become tightly woven into our biology. We
have coevolved with them, not just the plants, but the microbial species these ferments
contain in such abundance, especially ones such as
L. plantarum,
which for all
we know might be one of the unsung heroes of human health.

And yet it’s not at all hard to see
why it would take this long to recognize and appreciate the complexity of these foods
and these relationships—because that complexity is, literally, so hard to see. As with
the microbiota of the soil, another fermenting universe of biological complexity that it
closely resembles, the complexity of the gut microbiota is supremely difficult to
comprehend. So much more than the sum of its unprepossessing parts, it has been, until
very recently, invisible to the reductive lens of Western science, which has always been
better at understanding individuals (pathogens, variables, elements, whatever) than
communities. And then there is the fact that it utterly fails to conform to our
ideas—including our aesthetic ideas—of what a system or an organ should look like.
Let’s face it, the kilogram mass of microbes living in our gut don’t look
like much. It doesn’t help that we also find it disgusting.

A dairyman I know from Wales, a man who with
his son produces a remarkable cheddar, once told me that “everything”
affects the quality and flavor of his cheeses, up to and including “the mood of
the milker.” This struck me as a nice romantic conceit, until I pressed him to
explain how that might actually be so. “Well, it’s really quite simple. If
the milker is calm, the cow is calm. And a calm cow doesn’t shit as much in the
milking parlor, which means her milk will likely be cleaner. This is why the milk is
always better when women do the milking.”

Several things about this little story came
as news to me, not least the disturbing fact that there might be
any
shit in
milk, ever. The cheddar my friend makes is an organic raw-milk cheese, and I was a
little alarmed by what seemed like his cavalier attitude toward sanitation. Yes, you
wanted as little manure in the milk as possible, he was suggesting, but the reality of a
dairy farm is such that milk will never be perfectly sterile—and that isn’t
necessarily a wholly desirable outcome in any case. One of the reasons cheese makers
swear by the superiority of raw-milk cheeses is the complex flavors contributed by the
richly diverse bacterial cultures living in them. Where in the world did I
think
those came from?

In the intensifying struggle between the
Pasteurians and post-Pasteurians, raw-milk cheese has emerged as perhaps the single most
fiercely contested terrain. I have not given my friend’s name here because his
candor on the subject of shit-in-milk would probably bring the full force of the health
authorities down on his little dairy
farm. Live-culture sauerkraut and
kimchi makers have not had reason to fear predawn raids from the Pasteurian police, but,
rightly or wrongly, people selling raw milk and raw-milk cheese now do—they are bearing
the full brunt of the war on bacteria. Raw-milk cheese makers
are
subject to
predawn raids by the FDA, with SWAT teams brandishing guns showing up on farms
unannounced, pouring cans of fresh milk out onto the ground.

Milk was the first important food to be
subject to “pasteurization” by law, beginning in Chicago in 1908. So perhaps
it shouldn’t surprise us that milk and cheese would become ground zero in the
clash of worldviews between the public-health authorities—whose authority was founded on
Pasteur’s discovery of an invisible realm of disease-causing microbes—and those
who would seek to renegotiate our relationship to the microcosmos.

In fact, both sides in this struggle have a
compelling case to make, yet at the same time both sides seem blind to serious defects
in their own arguments. As Pasteurians are quick to point out, the reason we first began
pasteurizing milk (that is, heating it to 145°F for thirty minutes, or 161°F for fifteen
seconds, in order to kill bacteria) is very simple: Raw milk was killing lots of people.
Rich in sugars (such as lactose) and proteins (such as casein), milk is a perfect
breeding ground for bacteria, and in the nineteenth century it became one of the
principal vectors for the transmission of tuberculosis and typhoid. Pasteurization has
saved thousands of lives.

Ah, but that was then, the post-Pasteurians
reply. It is not at all surprising that milk was so badly contaminated in the
nineteenth-century metropolis. In the days before refrigerated storage and
transportation, fresh milk typically came not from cows in the countryside but from cows
brought into the city. Here, they were confined to dark, dank cellars, where they were
fed on brewery wastes and milked by wretchedly poor people carrying infectious diseases.
No wonder
raw milk could be lethal! Pasteurization is an industrial
Band-Aid applied to an industrial problem. As long as cows are given a proper diet and
good husbandry, it is unnecessary.

Yet even today, the Pasteurians respond,
when most cows once again live on farms, their milk can be contaminated with pathogenic
microbes, including such deadly (and novel) ones as
E. coli
0157:H7 and
Listeria monocytogenes
. The fact is that raw milk, and the cheeses made
from it, continue to kill a handful of people every year, and sicken a great many more.
So why take chances when we have a proven technology to ensure the safety of our
milk?

Reply the post-Pasteurians: People are also
sickened by cheese and other milk products that
have
been pasteurized, a
process that offers no guarantee of safety. Milk and cheese can be contaminated after
pasteurization, and often are. Also, the cleanliness of dairying has only gotten worse
under the regime of pasteurization; since dairy farmers know their milk will be
sterilized after it leaves the farm and gets mixed with milk from countless other farms,
they have less incentive to be scrupulous about hygiene.

Nowadays, the post-Pasteurians can cite in
their support the hygiene hypothesis. This is perhaps their most devastating argument,
though it, too, has unacknowledged weaknesses. According to the argument, the problem is
not so much with the bacteria in the milk, which they’re prepared to concede, but
with the compromised immune systems of us milk drinkers—compromised (need it be said?)
by years of misrule by the Pasteurians themselves, with their antibiotics, sterilized
food, and sanitized child-rearing regimes. The Pasteurian drive for absolute control of
the microbial realm has led to new vulnerabilities, reflected in antibiotic-resistant
microbes and lethal new pathogens.

Instead of technology, the post-Pasteurians
want us to put our faith in the microbes themselves and in striking a healthier, more
tolerant relationship with them. They cite studies demonstrating that
children who grow up drinking raw milk are measurably healthier than other children,
with markedly lower rates of allergy and asthma.
^*
Some of these children live in
environments teeming with deadly pathogens, including
E. coli
and listeria, yet
they don’t get sick from them. The post-Pasteurians further point out that the
best protection against bad bugs in milk or cheese is not the heavy hand of
pasteurization but, rather, the countervailing influence of various “good”
bugs, which pasteurization indiscriminately kills off. Milk and cheese are complex
ecological systems that can, at least to some extent, defend and police themselves.

This proposition, I was about to learn, is by
no means crazy. Sister Noëlla Marcellino is a cheese maker and microbiologist who would
probably describe herself as a post-Pasteurian (though with an important caveat I will
get to). In fact, one of the reasons she went back to school to become a microbiologist
(she was in her thirties at the time and already an accomplished cheese maker) was so
that she could scientifically test that very proposition.

The cheese nun, as she is inevitably called
in the numerous profiles about her that have been published and broadcast, has been
making a Connecticut version of a Saint-Nectaire since the late 1970s. Named Bethlehem,
for the rural Litchfield County town that is home to Regina Laudis, her Benedictine
abbey, Sister Noëlla’s cheese is a raw-milk, semihard, fungal-ripened cheese made
strictly according to ancient
techniques that have been practiced in
the Auvergne region of France since at least the seventeenth century. Sister Noëlla
learned the techniques, which are usually closely held family or village secrets, from
Lydie Zawislak, a third-generation French cheese maker who visited the abbey in 1977 at
the invitation of the Abbess. Sister Noëlla had been attempting to make cheese from the
abbey’s surplus of milk, but found cheese making was a craft you couldn’t
learn very well from a book.

“So I began praying for an old French
lady to come teach me,” she recalled. Her prayers were answered when Lydie came to
visit. (Lydie wasn’t old, however.) Monasteries have historically been places
where traditional food-making techniques, many of them involving fermentation, have been
scrupulously perfected and preserved; Lydie was willing to entrust her family’s
Saint-Nectaire recipe to Sister Noëlla and the abbey.