Nattō, Sushi, Umami

1.       Nattō (なっとう or 納豆) is a traditional Japanese food made from soybeans fermented with Bacillus subtilis. It is popular especially as a breakfast food. As a rich source of protein, nattō and the soybean paste miso formed a vital source of nutrition in feudal Japan. Nattō can be an acquired taste because of its powerful smell, strong flavor, and slippery texture. In Japan nattō is most popular in the eastern regions, including Kantō, Tōhoku, and Hokkaido. 

An acquired taste often refers to an appreciation for a food or beverage that is unlikely to be enjoyed by a person who has not had substantial exposure to it, usually because of some unfamiliar aspect of the food or beverage, including a strong or strange odor (e.g. stinky tofu, durian, kimchi, haggis, hákarl, black salt, stinking toe, asafoetida, surströmming, or certain types of cheese), taste (such as root beer, vegemite, bitter teas, salty liquorice, garnatálg or natto), or appearance. Acquired taste may also refer to aesthetic tastes, such as taste in music or other forms of art.



2.       What You Don’t Know About Sushi

Think you know a thing or two about sushi, eh? Yeah, I thought the same thing until today. Today is when Trevor Corson, author of The Zen of Fish: The Story of Sushi, from Samurai to Supermarket made a guest appearance on my local radio station to dispell some commonly held myths about sushi.

Now, I’ve traveled to Japan, and I’ve eaten at some good sushi establishments. I’m not an expert by a long shot, but I thought I knew a thing or two about raw fish (sashimi) and the rice beneath it (sushi). But alas, ’twas not the case.

 Fresh isn’t necessarily better

No, I don’t recommend you save money by buying week-old sushi or anything. That said, I was always under the impression that the freshest sushi was the most recently deceased. Not true. Like beef and lamb, fish actually has to age slightly in order to achieve a full, rich flavor.

The reason for this, according to Corson, is that the enzymes in fish flesh start to break down the muscle once a fish dies. And that breakdown actually creates smaller molecules that are detectable as flavorful by the human tongue.

Corson goes into a brief but fascinating discussion of glutamate (that’s the G in MSG), a flavor that is designated as the fifth “taste” that the human tongue can detect. The Japanese call this flavor umami, which we translate into English as savory. Much of Japanese cuisine’s flavor comes from fermented or aged produce — soy sauce, natto, bonito flakes, and miso are all created through some practices that we, as Westerners, might consider unsavory.

Fresh fish is delicious if you just caught some trout and cooked it over the campfire with some lemon and butter. But try to eat the same fresh fish raw, and you’re likely to be disappointed.

 Most of the sashimi that we eat in restaurants has been flash frozen using liquid nitrogen. This process kills many of the germs and worms that can develop in fish flesh, but doesn’t cause any physical deterioration of the meat.

When you go into a fine sushi establishment and order the freshest daily fish, you aren’t eating fish that was caught the same day, or even the day before. If you’re eating good sushi, the fish is at least a few days old. 

You’re not supposed to use chopsticks

Dammit! The one skill that I can use across East Asia, and it doesn’t even apply?

Lots of sushi that we eat in American sushi establishments comes in the “roll” format. Traditional sushi is eaten in the nigiri format — a little polyhedron of loosely-packed, slightly sweet and tangy sushi rice topped with a thin slice of raw fish. Ever notice that the sushi sort of breaks apart when you dip it in that little bowl of soy sauce and then try to pick it back up with your chopsticks? That’s because you are supposed to eat it with your hands.

I kid you not. Traditional sushi lovers do exactly that. Corson has a guide of how to eat sushi on his web site. The sushi rice is not usually packed very tightly together, which is why it falls apart when you try to eat it with chopsticks. The method for eating sushi is more or less to hold the sushi piece like it’s a computer mouse, slowly flip it over, and lightly drench one side in the nikiri sauce (soy, depending on where you are eating) provided.

By now you’ve probably seen that comedic video of Japanese etiquette that pokes fun at the traditions and mannerisms that surround sushi consumption. It turns out that much of the behavior is as baffling to the Japanese as it is to Americans.



3.       Umami, a savory taste, is one of the five basic tastes, together with sweet, sour, bitter and salty. A loanword from the Japanese (うま味), umami can be translated “pleasant savory taste”.[4] This particular writing was chosen by Professor Kikunae Ikeda from umai (うまい) “delicious” and mi (味) “taste”. The kanji 旨味 are used for a more general meaning to describe a food as delicious.

The human tongue has receptors for L-glutamate, which is the source of umami flavor. For that reason, scientists consider umami to be distinct from saltiness.

Many foods that may be consumed daily are rich in umami. Naturally occurring glutamate can be found in meats and vegetables, whereas inosinate comes primarily from meats and guanylate from vegetables. Thus, umami taste is common to foods that contain high levels of L-glutamate, IMP and GMP, most notably in fish, shellfish, cured meats, vegetables (e.g., mushrooms, ripe tomatoes, Chinese cabbage, spinach, celery, etc.) or green tea, and fermented and aged products (e.g., cheeses, shrimp pastes, soy sauce, etc.).

Humans’ first encounter with umami is breast milk. It contains roughly the same amount of umami as broths.