Delicious Fermentation

Ioku: Mr. Namae, although you are a French cuisine chef, you have a great interest in fermentation technology, don't you? Namae: My mentor is a man named Michel Bras, who runs a restaurant in the French countryside. It's a restaurant sitting all alone on a hill in a remote area with nothing around it, yet people from all over Europe drive there in Porsches and Ferraris. Seeing that, I wondered what it was that fascinated people so much. My mentor often told me, "Live and cook with sincerity toward the place where you stand, the place where you were born and raised." He would also ask me sternly, "You were born and raised in Japan, and Japan has various deep cultures, including its cuisine, so why do you leave your country to come and learn French cuisine?" I was so fascinated by him that I have been asking myself this question ever since. After completing my training and opening my own restaurant, I revisited that question and decided to relearn Japan—to study the things I had ignored until then. Ioku: That's where you encountered fermented foods. Namae: Yes, I inevitably ended up coming into contact with many fermented foods. I was asked many questions about Japanese fermented foods by overseas chefs and food specialists. I felt very ashamed that I couldn't answer them. So I studied again and visited as many sake breweries, soy sauce breweries, miso breweries, vinegar breweries, and production areas for things like "shottsuru" and "ishiru" as possible. Even now, I am still in the middle of learning various things. Also, interacting with overseas chefs through fermentation has reignited my passion. Since they don't have a set theory, they just pick up the technical aspects and start creating their own original fermented foods. Because of that, many things that never existed in Japan before are being born. Koizumi: I see, that's interesting. Namae: Japanese fermentation technology is now starting to spread and take root worldwide, becoming a part of global originality. I feel that a very interesting scene is emerging.

Ioku: Since my student days, I have been studying the economic development of the Edo period. At that time, it was often generally said that the Edo period was a stagnant era, but around the time I was a student, professors like Akira Hayami and Nobuhiko Nakai began to say that the Japanese economy developed considerably during the Edo period. Then, when I investigated various things in the Kanto region, I found that agricultural production had indeed increased significantly in Kanto by the late Edo period. As a result, people who previously had their hands full just paying land taxes and feeding themselves began to have some leeway and started processing surplus agricultural products to make something. In that case, the Kanto region's geology is a loam layer, which is very suitable for the production of soybeans and wheat. That's why the soy sauce brewing industry developed. I think soy sauce is a truly mysterious seasoning. Standardly, it takes about a year to make. It also involves diligently stirring it every day to promote fermentation. Among the ethnic groups of the world, there are probably not many others like the Japanese who spend a whole year diligently making a seasoning every day. Koizumi: In the case of Japan, I think that style of making things diligently spread from around the Edo period. Also, Japan is a culture of wood. We had wooden barrels (oke). These barrels made it possible to age soy sauce, miso, and sake for a long time. The core of this Japanese fermentation culture is koji. Soy sauce koji mold, miso koji mold, sake koji mold, and so on. However, koji mold doesn't ferment immediately; it ferments over a long period to bring out the flavor. Then lactic acid bacteria and yeast come in, and it ferments slowly. Through such aging, the taste becomes very good.

Koizumi: One characteristic of fermented foods is that they are very stable and almost never rot. Even as a microbiologist, I find this very mysterious. For example, if you leave milk out, it rots quickly, right? In summer, it's gone in a single day. But if you add lactic acid bacteria to make yogurt, it doesn't rot. Even with natto, you eat the boiled soybeans just as they are after the natto bacteria have multiplied. Even if you leave it out, it hardly rots. In the era before refrigerators, people fermented food to preserve it. Second, fermentation significantly increases nutritional value. Microorganisms create various things like vitamins and amino acids. Moreover, it's recently been said that it even enhances immune activity. That's how fermentation produces things that are very good for the body. Third, the taste and smell are indescribable. In my case, the smell of kusaya just makes me tingle (laughs). So, the taste and smell are characteristic. These cannot be created by human power alone. To add one more thing, fermented food is the ultimate natural food. In other words, there are no additives. Even with miso, you ferment soybeans, koji, and salt, and eat it as is. No additives, no chemical seasonings, no synthetics, nothing. That's why I think it's the kindest food for the body. Japan is the country with the most fermented foods in the world. This is also related to the climate; for example, in East Asia, there's China, the Korean Peninsula, Taiwan, and Japan. In Southeast Asia, countries like Thailand, Vietnam, Myanmar, Cambodia, and Laos all have fermented foods. However, only Japan uses koji mold. In Korea, China, and Southeast Asia, they all use a mold called Rhizopus for fermentation. That's the difference. Ioku: So koji is unique to Japan. Koizumi: There are two types of koji mold: yellow koji mold and black koji mold. These are used only in Japan and are hardly found in other countries. In 2006, koji mold was designated as the "national fungus." It's the fungus of the nation. Yellow koji mold is used to make miso, soy sauce, sake, mirin, rice vinegar, and so on. Black koji mold is used only for shochu. Okinawa's awamori and Kagoshima's sweet potato shochu all use black koji mold. In 2013, the International Union of Microbiological Societies named the black koji mold from Okinawa and Kagoshima "Aspergillus luchuensis," after "Ryukyu."

Ioku: When studying the history of soy sauce, I ultimately end up thinking about what Japan is and what the Japanese people are. I feel that soy sauce is something very characteristic of the Japanese. Even watching the craftsmen who make it, it feels like they are having a dialogue with the koji mold. They work diligently every day to ensure it ferments evenly, worrying about it fermenting too much or too slowly. Koizumi: Exactly, a craftsman is like an orchestra conductor. Ioku: That delicacy and diligence make me feel that it's a seasoning that fits the Japanese people very well. Koizumi: Nowadays, if you go abroad and say "shoyu" or "soy bean sauce," they might not understand, but if you say "Kikkoman," they do (laughs). Ioku: I've heard that koji mold is a very miraculous fungus; while most relatives of koji mold are poisonous, only koji mold is not. Koizumi: Aspergillus oryzae is the yellow koji mold, and since Japan is a country of rice, "oryzae" comes from rice (oryza). It means a koji mold that grows well on rice. However, among the same Aspergillus relatives, there is Aspergillus flavus. This is a deadly poison among poisons, producing aflatoxin, a very strong carcinogenic substance. Taxonomically they are both Aspergillus, but the Japanese Aspergillus does not produce poison. This is one of the characteristics of Japanese koji. Another clear point is that only in Japanese koji does the mold grow separately on each individual grain of cereal. This is called "bara-koji" (scattered koji). However, from the Korean Peninsula onwards, all koji outside of Japan is "mochi-koji" (cake koji). In other words, it's shaped like a dumpling, a rice cake, or a brick. So, it's completely different in that respect as well.

Ioku: Around when did the Japanese become aware of the existence of these "microbes"?

Koizumi: In terms of microorganisms, it's said that the Dutchman Leeuwenhoek first created a microscope in the 17th century and discovered the existence of microscopic creatures, but in Japan, there was a business selling microorganisms 400 years before that. This was during the Heian period. What was it? It was the tane-koji (koji starter) sellers. Of course, the word "microorganism" didn't exist yet, but there was an awareness that it was something mysterious. If you leave steamed rice out, mold grows on it. That is called koji. The definition of koji is cereal with mold growing on it.

Ioku: So they had noticed it quite a long time ago.

Koizumi: To begin with, koji appears in the "Harima no Kuni Fudoki" from the Nara period. In what is now Shiso City in Hyogo Prefecture, there is a shrine called Iwa Shrine, and in the "Harima no Kuni Fudoki" compiled there, something amazing is written. Steamed rice was offered to the gods. It became old, and mold grew on it. That was called "kabitachi." "Kabitachi" became "kamutachi," then "kamuchi," then "kauji," and finally "koji." So, the existence of koji was already there in the Nara period. Only mold comes to the rice cakes offered on the family altar. If you boil rice, it won't get mold because it has too much moisture. It won't come to parched rice either. Mold only comes to steamed rice. That is the beginning of koji. If you steam rice and leave it, mold will grow and it will become koji, but it was actually the late Heian period when only the good koji was selected. If you sprinkle ash on it, miscellaneous bacteria are eliminated and only the koji mold emerges. I think this might be the first pure isolation by mankind. Then it is passed through a silk sieve. The mesh of a silk sieve is just the right size for koji mold spores to fall through. Collecting those, the tane-koji sellers began selling them to sake brewers and miso makers. This was the early Muromachi period. It's amazing that the Japanese were doing such things so long ago. In that sense too, I truly feel that Japan is a country of Aspergillus oryzae.

Koizumi: Is the involvement of French and Italian chefs with fermentation technology different from that of Japanese chefs?

Namae: Yes. For Japanese people, soy sauce is recognized as something that has been there since birth, but for foreigners, the technology and process of fermentation are very unique and new. In English terms, it feels "hip" and "cool."

Koizumi: I see.

Namae: Also, the countries trying to adopt fermentation technology are not France, Italy, or Spain, which have been the centers of European culinary hegemony, but rather remote areas, and often regions where food had to be preserved. In Northern Europe—Denmark, Sweden, and Norway—they are successfully creating synergy between Japanese fermentation technology and their own traditional preservation techniques. Of course, the ingredients are different; basically, they can't grow soybeans or rice in their lands. So, for example, they dry green peas and make miso from them, or make koji from barley to create fermentation starters. Also, they take things high in protein but low in fat to make original soy sauce and miso. An interesting example is soy sauce made using grasshoppers and locusts. They make soy sauce using only koji started on barley, salt, water, and grasshoppers. Koizumi: That's interesting.

Namae: It's a kind of soy sauce that ordinary Japanese people wouldn't think of.

Koizumi: You just mentioned locust soy sauce, but actually, the Engishiki (a book of laws and customs) from the Heian period states that there were four "hishio-ya," or soy sauce shops, in the city of Kyoto. They were koku-hishio (grain soy sauce), uo-hishio (fish sauce), shishi-hishio (meat sauce), and kusa-hishio (vegetable soy sauce). At that time, the Japanese were already making four types of soy sauce. When I found this, I thought that the people of the Heian period might have been more gourmet than modern people. Meat sauce doesn't exist anymore today, but in the Heian period, it was made with duck meat. The last one to remain was a meat sauce made from streaked shearwaters on Mikurajima, one of the Izu Islands, which I believe existed until around 1952. We are now starting to make pork soy sauce in Ishigaki City, Okinawa. Everyone is very interested, and when used in ramen soup, it's incredibly delicious.

Ioku: During the Edo period, when Japan was closed to the outside world, a small amount of soy sauce was exported from Nagasaki to the Netherlands. There is a story that it reached France and King Louis XIV was very pleased with it. Since then, stories remain that Japanese soy sauce was used as a secret ingredient among court chefs in Europe, albeit in small quantities. Nowadays, Kikkoman's production volume overseas is already greater than its domestic production in Japan.

Namae: It feels like soy sauce equals Japan. I think it has become completely established as a Japanese taste. However, I also feel that many people might not understand what soy sauce actually is. I wonder how many people know that it is made through slow fermentation and becomes soy sauce after aging.

Ioku: What is the position of soy sauce for foreign chefs?

Namae: When you go to the kitchens of restaurants in Paris, Kikkoman is always there. However, Europeans use Southeast Asian fish sauce as well as Japanese soy sauce and miso. In that sense, they might group them all together as Asian seasonings. There is a sense that they are trying to master various Asian fermentation technologies—including Japanese soy sauce, Korean ganjang, and the fish preservation methods of Laos and Cambodia—according to their needs. Within that, they are thinking about where to focus the deliciousness. If anything, I think Europe previously had a strong tendency to prioritize fats and oils. On the other hand, Asia emphasizes amino acids. How to control amino acids—this is also a way of interacting with soy sauce. And there is a strong interest in how to make delicious things using water, and it feels like Europe is also shifting from fat to water.

Ioku: In Japan, soy sauce is one of the brewing industries; sake, soy sauce, miso, vinegar, and mirin are all part of the brewing industry. "Brewing industry" would be translated as Brewing Industry in English, but it seems that for foreigners, "Brewing" has the image of only making alcohol.

Koizumi: Yes, in Japan, everything can be expressed with just the word "jozo" (brewing). Tokyo University of Agriculture still has a Department of Brewing Science. About 20 years ago, when I was a professor, there was talk of changing the name to Department of Food Industry or Department of Food Science to attract more students because the name "Brewing" was old, but I strongly opposed it. I argued that since the word "brewing" (in this broad sense) is unique to Japan, it must be preserved as a traditional Japanese culture. Now, there is only one Department of Brewing Science left in Japan.

Ioku: I once saw you on TV, Mr. Koizumi, eating 40-year-old carp narezushi from China. Are you okay after eating something like that?

Koizumi: I tried eating that sliced thinly, and it was completely cheese. Everyone says Japan didn't have cheese, but that's nonsense. In Japan, cheese is narezushi. We just didn't have the word "cheese." Cheese is animal milk, right? It's high in protein and fat. Take, for example, funazushi from Omi. This is also protein and fat. So, if you make cheese with lactic acid bacteria isolated from narezushi, you can make perfectly fine cheese and yogurt. Conversely, you can make narezushi using cheese bacteria. In other words, narezushi is what was made in Japan by fermenting animal protein to create the same thing as cheese. Japan didn't have cows, but it had plenty of freshwater fish, and those were fermented. Initially, it was probably for preservation. So, when analyzed, narezushi and cheese have almost the same components. The smell is also similar. Especially "hon-narezushi," made by pickling mackerel for a long time, is exactly like intensely smelly cheeses like Gorgonzola, Stilton, or Epicure cheese. In Shingu City, Wakayama Prefecture, there is a restaurant called Toho Chaya. They currently sell 30-year-old saury narezushi. It's not that expensive. When I have students taste it with a spoon while blindfolded, 100 out of 100 answer, "It's melted cheese." If you eat it on a cracker or something, it really feels like blue cheese. You can make that with saury.

Ioku: I'd like to try that once.

Koizumi: So, fermented foods can be preserved indefinitely. Then, why can they be preserved once fermented? There are two reasons. First, when microorganisms ferment, that place becomes their habitat, so they create inhibitors that prevent other bacteria from multiplying. These are called antibiotics. And second, the microorganisms themselves possess elements that prevent rotting. For example, in the case of lactic acid bacteria, when they produce lactic acid, it becomes acidic, and other bacteria cannot come there. Natto is the same. This fermentation technology is also used in medical sciences. Without fermentation, surgery would be impossible. Antibiotics are things produced by microorganisms. If you don't administer antibiotics and perform surgery, the cut area will fester.

Ioku: There are various fermented foods all over the world, but are there any that you think are truly amazing?

Koizumi: What I think is the rarest fermented food in the world is the rice bran-pickled pufferfish ovaries from Ishikawa Prefecture. Pufferfish ovaries contain a deadly poison called tetrodotoxin. This tetrodotoxin is 180 times more toxic than potassium cyanide, and normally, you would die just by licking it a little. However, these rice bran pickles have been made since the Edo period and are still commonly sold today. They are made in a place called Mikawa, Hakusan City, and it takes three years to remove the poison before they can be eaten. Pufferfish ovaries are large, but when you salt them, the salt removes the moisture, so they become much smaller. After salting for about six months to remove moisture, they solidify to some extent. Then, putting them in fresh water allows for desalination. But the poison is still not gone. So, next, they are pickled in rice bran miso and left for three years. Then, the poison disappears. This is sold as a product. I have never heard of anyone dying from eating this. However, there is know-how in the production method, so do not try to imitate it.

Ioku: Why is the poison removed?

Koizumi: It's decomposed by microorganisms after all. In one gram of rice bran miso, there are about 180 million lactic acid bacteria. Pufferfish ovaries have a thin membrane like mentaiko. That membrane gets damaged during salting and other processes. To a single microorganism, a single lactic acid bacterium, that damage is as large as the Tokyo Dome. Microorganisms enter the ovary through such damage and multiply. Since they don't have blood vessels or blood, poison doesn't matter to them. They take the chemical substance called tetrodotoxin into their bodies and live by decomposing it into ammonia, water, and carbon dioxide. I call this detoxification fermentation. This detoxification fermentation is truly unique to Japanese rice bran-pickled pufferfish ovaries. It absolutely exists nowhere else in the world.

Namae: It smells like cheese or rice bran miso, doesn't it?

Koizumi: It's hard, but when you cut it open, the beautiful ovaries are packed tightly with little grains like herring roe. You can sprinkle it over rice and eat it, or make chazuke or yuzuke. The acidity, umami, and smell of these ovaries—I think it would be interesting to use this as a secret ingredient in cooking.

Koizumi: If rice bran-pickled pufferfish ovaries are the Yokozuna (grand champion) of the East, the Yokozuna of the West is kiviak. It's a fermented food made by the Inuit.

Koizumi: First, they catch a large seal weighing about 200 kilograms, remove the internal organs and meat, and leave the skin. Inside that, they stuff about 200 to 300 little auks. They bury it in the ground, cover it with soil, place many stones on top, and let it ferment for three years.

Koizumi: They place many stones on top to prevent bears and Arctic wolves from coming and digging it up to eat. After three years, they dig it up. Since about 300 birds were stuffed in without even removing their feathers, they come out fermented just as they were. This is intensely smelly. To the point where you'd think nothing could be this smelly.

Ioku: That's quite a grand scale (laughs).

Koizumi: As for how to eat it, you take out a bird, put your mouth to its anus, press the body hard, and suck. Since the body fluids are also fermented and syrupy, the internal organs and meat come into your mouth all gooey. Apparently, Naomi Uemura loved this kiviak.

Koizumi: Why do they eat such a thing? Because the Inuit cannot cultivate vegetables, they cannot get vitamins. Since vitamins cannot be made in the human body, they must be taken from the outside. The intestinal bacteria of walruses and seals produce many vitamins, so they eat the contents of those intestines attached to raw meat like birds. I think they eventually invented kiviak. When you analyze kiviak, it's a mass of vitamins.

Koizumi: Besides just sucking it out, they also freeze it for preservation as a seasoning. When thawed and squeezed hard, a syrupy paste like bean jam comes out. The meat and internal organs have fermented into a slurry. They eat that by attaching it to caribou or reindeer meat.

Ioku: Did you eat it too, Mr. Koizumi?

Koizumi: Yes, I ate it. Anyway, it's smelly! As for the taste, in Mongolia and Inner Mongolia, there is a sausage made by putting blood into sheep intestines, and it has that same sticky texture as when you eat that boiled. However, the smell is intense.

Ioku: Something often mentioned as a smelly fermented dish is surströmming from Finland.

It's like a canned hell (laughs). That one is incredible too. It's fermented herring, but it smells so bad that there are three warnings when opening the can. "1. Never open it inside the house." "2. The person opening it should wear clothes they don't mind throwing away." And the third is, even when opening it outside, "Make sure there is no one downwind" (laughs).

According to research at a Tokyo Institute of Technology lab, the smell of natto is about 470. Uncooked kusaya is about 680, and grilled kusaya is about 1200. For reference, my socks are about 120 (laughs). But when you pop open a can of surströmming, it jumps to about 12,000.

At that point, it's practically a hazardous material (laughs).

That's what makes fermentation so interesting. However, the smell of fermented food is somehow attractive. Whether it's kusaya or natto, it's the same. If natto didn't have that smell, you wouldn't feel like eating it at all. Ultimately, that kind of smell is actually something like the original scent of human beings.

For example, you have people who are slovenly—those who don't take a bath for a week or two. Similarly, there is a "slovenly smell." It's the smell of things like narezushi or natto.

To begin with, humans didn't always take baths every day. That kind of smell is the starting point for humanity. So, I think of it as something like my own hometown (laughs).

That way of living might actually be more human. Smelly people might be healthier (laughs).

There is research suggesting that if we become too clean, we can't live as long. Perhaps we should return more to the wild.

Connecting to what Mr. Koizumi said, I feel that modern civilization has drifted quite far from nature. The concept of "culture" is how humans face that nature.

We tend to think of culture as art or systems, but apart from that, I think there is a perspective of how nature and humans find a compromise. Therefore, I believe that cultivating bacteria is also a form of culture.

Exactly.

Even in the city, if fermented things are close by, you can find a small piece of nature there.

When living in a very clean and sterile building in the city center, it's difficult to be conscious of our relationship with living things. But, for example, if you have a nukadoko (rice bran bed) or your own homemade miso nearby, their appearance, aroma, and taste change every day.

That is truly a culture, and it makes us feel a connection with nature. Fermentation exists there, a medium is created through fermentation, and delicious things are born.

When we say "delicious things," there's an image of them being pieced together like a plastic model, but that's not it. I think that for something to be truly delicious, there must first be an environment, and then you create that culture using the ultimate technology of fermentation. I feel that is the entrance to the connection with nature that humans perceive as "delicious."

I see. The act of cultivating itself is culture. When you watch the actions of these microorganisms, there is a profound sense of mystery. For example, lactic acid bacteria, natto bacteria, and acetic acid bacteria—even though they are tiny things only about 1/2000th of a millimeter, they have the same bodily functions as humans.

All their genes are already built into that tiny body. They properly take in nutrients, metabolize them, create energy, and even give birth to offspring. Just the fact that such things are built into such a small life form feels very mysterious. It's fascinating to think that a collection of such things brings us miso, soy sauce, and sake.

In our daily lives, we often end up living centered around things we can see and feel with our five senses. Therefore, things that are invisible, or things we cannot smell or touch, tend to be overlooked. But from my perspective, being able to connect with that invisible world is very romantic.

It might sound cliché, but I feel it's close to conceptual things like love. Yet, our daily lives exist while being protected by such things.

Microorganisms can, of course, be seen under a microscope and pursued chemically, but the way we interact with bacteria in daily life is very close to something conceptual that sets human life straight. It's like being protected by an invisible force.

Microorganisms create delicious things, but in some cases, they can even kill people.

There are good bacteria and bad bacteria. Bad bacteria include spoilage bacteria that rot food and pathogens that cause disease. These are different from fermentation bacteria.

Good bacteria are things like natto bacteria, lactic acid bacteria, acetic acid bacteria, yeast, and koji mold, and humans only cherish this group. Even though they are invisible, humans can distinguish and choose to use them. I think the skill involved in that is also part of the wonder of fermentation.

Fermentation is primarily the work of breaking down large things. It's not making large things even larger, but breaking them down into smaller pieces.

If we translate that into human activity, when we eat, we put large things in our mouths and break them down into smaller pieces through saliva, gastric juices, and intestinal absorption. In that sense, I feel like I am also performing fermentation. What the bacteria are doing and what I am doing are actually very similar.

That's true. There is much we can be taught by microorganisms.

The technology of fermentation seems like it will be a great hint when thinking about the future of cuisine.

I want to trace back further into the Asian culinary culture that Japanese people originally originated from. I believe we can see things there that connect to the present and the future. As an Asian myself, I want to utilize the ideas born from that in my cooking. To put it a bit grandly, it would be a post-colonial way of approaching cuisine.