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Spoiled Rotten: The Pungent Pleasures of Natto

November 17, 2016


Photo by Marcus Hutchings

Japanese cuisine has made great strides in winning over the West. Once upon a time, the mere mention of sushi was more than likely to be met with a confused stare, if not a grimace of disgust. Fast forward two or three decades, and just look at how high washoku’s star has risen. Japanese food is everywhere. From Vancouver to Versailles, fine-dining to food trucks, the world is simply mad for it.
Naturally, a certain amount of absurdity has ensued. Western foodies now namedrop pedestrian Japanese basics, such as panko or edamame, with the kind of hushed knowingness once reserved for the rarest black truffle.
But one fixture of the Japanese dining table that has yet to enjoy its 15 minutes of fame is natto. It's not hard to see why. Next to sushi's simple elegance and glamour, poor natto remains the ugly duckling of washoku - a sticky, stringy, malodorous mystery that divides even the Japanese.

What is it?

Perhaps one reason natto remains such a well-kept secret outside of Japan is the unfortunate way it is often described. Ask a Japanese person what it is you’re about to eat, and, after a moment of deliberation they will likely tell you “rotten soybeans”. Now, while technically this may be true, it is unlikely to entice even the most open-minded Western diner. Rather, it sounds more like a dare than a dinner.
If one is trying to tempt a friend into trying it for the first time, “fermented soybeans” may be a gentler way to phrase it, but still don’t expect much enthusiasm. Perhaps try a different approach, and extol the health benefits of natto. While soybeans are already rich in protein, fermenting them pushes their nutritional value into “superfood” territory. Cholesterol and gluten-free, natto boasts a shopping list of beneficial assets, including iron, calcium, soft dietary fiber, vitamins B6, B2, E, K2, and many more.
Natto, then, is simply soybeans fermented with the Bacillus subtilis bacterium, known as “natto-kin” in Japanese. Skeptics may be relieved to know that in modern facilities, natto is prepared under very strict, sterile conditions. The beans are washed, soaked, steamed, then mixed with natto-kin and fermented for about a day. Once the fermentation process begins, every effort is made to protect the beans from impurities, especially those introduced by human hands.
The end result - brown, pungent beans coated in a stringy slime - is usually packaged in neat, white polystyrene containers, with small sachets of soy sauce and Japanese mustard.
But things were not always so neat and tidy for these ripe little beans. As with most homespun favorites, the origins of natto are somewhat hazy, but most accounts agree that it was discovered quite by accident when soybeans were packed in rice-straw, a natural habitat for Bacillus subtilis bacterium. Natto appears in documents from as far back as the 11th century, though it is commonly believed to have been around for much longer. One of the more colorful stories involves the Heian period samurai Minamoto no Yoshiie (1039-1106). Apparently, while on a campaign in Northeastern Japan, he and his men were busy boiling soybeans for their horses when they were attacked. This rude interruption forced them to hurriedly stow the beans in rice-straw bags, and get on with the more urgent business of fighting for their lives. Several days later, presumably hungry from dispatching their rivals, the men opened the sacks, found that the beans had spoiled, and decided to eat them anyway. Yoshiie and his minions were pleasantly surprised by the gooey legumes, and the rest, as they say, is history.
Since then, as we know, natto production has become much more predictable and sanitary, but some manufacturers still offer their wares packaged in straw, presumably for a touch of old-school flavor.

Yes, but what's it actually like?

The first thing most people notice about natto is the smell, and it is this factor that often prevents the timid from actually trying it. Like most fermented foods, natto has a strong, distinct odor, not dissimilar to ripe cheese. Whether you find this seductive or repulsive really depends on your personal taste and the associations the smell conjures up. Those who wish to proceed further may be surprised to find that the taste is actually quite mild in comparison. Of course, natto is most commonly seasoned with soy sauce and Japanese mustard, which adds some umami and tang, but the unique flavor still stands out. It’s difficult to describe, but I have heard it likened to coffee, and even foie gras, by those who enjoyed the experience. Reactions from the other end of the spectrum, however, are probably best not repeated on a polite food site.

Natto’s texture is another point of controversy. The beans themselves are unchallenging enough - the smaller varieties tend toward the firm and chewy, while larger beans may be soft and creamy, not unlike refrigerated butter. What turns many people off is the frothy mucilage that appears once you begin stirring the beans. This is much like “tororo”, the gluey result of grating wild yam. Scooping up a mouthful reveals surprisingly resilient, webby strings similar to those found in okra. Much like natto’s unusual smell, this can either prove mouthwatering, or deeply unsettling, to the potential diner.

Many will seize on this divided reaction to natto as further proof of Japanese uniqueness, as yet another food that Westerners “cannot” eat. But the Japanese people are far from united in their love for this sticky staple. While natto seems to be universally adored in Northern and Eastern Japan, residents of Western Japan are said to be much less keen on it. It has been suggested that this is related to rice production, and the resulting bacterium-rich straw, being more historically concentrated in the North and East of the country. The cooler climate of Northern Japan would also have been more conducive to keeping natto properly preserved. Another theory is that the popularity of natto roughly corresponds to the travels of our previously-mentioned samurai Yoshiie and his army. Whether you believe that natto’s popularity comes down to climate, ancient farming trends, or Yoshiie’s gastro-evangelism, one fact is clear: The Japanese are far from homogenous in their tastes.
It seems, too, that they are not alone. Though most Westerners remain unaware of, or immune to, the charms of spoiled soy, similar products in other countries show that it is far from a uniquely Japanese phenomenon. In fact, soybean dishes fermented with Bacillus subtilis can be found as far afield as China, Korea, Myanmar, Thailand, Nepal, India, and West Africa.

Let's eat!


Photo by Marcus Hutchings

Having gotten more or less to the bottom of the natto phenomenon, there remains only one thing left to do - try it out.
For an authentic first experience, it’s probably best to keep it simple, the way it’s generally enjoyed across (most of) Japan. The typical Japanese natto lover will have it with any meal, but most often as part of a simple breakfast with rice and miso soup. After opening the container, and squeezing the provided condiments on top, he or she will mix up the contents with chopsticks. How long to stir the natto is yet another point of disagreement, but around one minute seems a safe bet to achieve the desired froth and stringiness. It is then poured over the rice, mixed in, and eaten. Some people like to add a raw egg, or green onion for a little more nutrition and flavor.
While this is the most common way to have it, natto is actually quite versatile. It’s often found in sushi, rolled omelet, savory okonomiyaki pancakes, and miso soup. You may try adding it to spaghetti, waiting until the last moment so as not to diminish the nutrients by overcooking. Natto also goes surprisingly well on toast, something those who enjoy the similarly divisive British or Australian yeast spreads may find familiar. Try melting a little shredded cheese on top, and you may just have found the comfort food you’ve been seeking your entire life.

Don’t worry about the rules. Don’t listen to the naysayers. Natto’s potential is limited only by your imagination.

Text: Marcus Hutchings

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