A visit to rural Japan to look closely at the past, present, and future of the salty Japanese condiment.

The port city of Ono in Japan has been a hub of soy sauce making for centuries. Its proximity to fresh water trickling down from the nearby Mount Hakusan and docks for exporting the finished product made it one of Japan’s largest soy sauce brewing regions during the 17th and 18th centuries. Today, around ten artisanal soy sauce makers remain. Hiraku Ogura, a fermentation expert who curated the Ferment Arts and Culture Festival at the 21st Century Museum of Contemporary Art in Kanazawa this year, took us inside one of them, the 100-year-old Yamato Shoyu & Miso.

Ogura has been leading “fermentours” of Japan for the last couple years, and I joined a recent tour in October, which was focused on Ishikawa prefecture. He’s a thin man in his thirties, dressed in an orange anorak and a bowler hat, and his deep knowledge of all things fermented became evident as soon as we were assembled inside the brewery. He stood before a large dry-erase board that he’d marked up with ratios, chemical reactions, and drawings illustrating the journey of soybeans and wheat into soy sauce—or more specifically, shoyu, the prevalent style of Japanese soy sauce, made from roughly equal parts wheat and soybeans. But to learn about shoyu, we first needed to learn about koji, the mold-inoculated rice that forms the basis for the flavors found in soy sauce and miso. Ogura drew an oversize rice grain on another dry-erase board and dotted its perimeter with little antennae with bulbs at the tips. Then he drew veins from the antennae burrowing inside the rice grain to represent the enzymes developing within.

The 20 tour participants drew diagrams in notepads and angled their iPhone cameras to capture the board. They were a group of avid home fermenters, chefs, and educators, alongside a couple of media invitees like me. Ogura had mapped a three-day itinerary of artisanal soy sauce, vinegar, and sake breweries to visit, along with a maker of rice bran–preserved fugu, or puffer fish. Along the way, we shared meals highlighting fermented products; mixed mountains of moist rice for koji making; munched on sake lees, a flavorless paste that’s a by-product of sake making; and dipped our hands into amazake to experience the fermented rice drink’s famed silky, skin-softening properties. The tours are cohosted by San-J, a brand best known in the United States for selling tamari, a type of Japanese soy sauce made from all or mostly soybeans and no wheat. Canvas tote bags depicting a bottle of San-J organic tamari were handed out to each participant on day one of our tour. Only we didn’t hear anything about tamari on the tour. I didn’t see the word on any dry-erase board, product label, or museum exhibit.

“It’s such a beautiful dark amber liquid that is basically, for me, a jewel.”

When I approached Ogura and asked him about tamari in Japan, he said it was a regional product, found only in the Aichi, Gifu, and Mie prefectures. And, he said, there were only a small handful of breweries still making it.

“If you’re from that region, you maybe use it because it’s nostalgic,” he explained. Otherwise, most people in Japan don’t have tamari in their cupboards.

Intrigued, I spent the next two weeks shaking off jet lag and trying to find out the tamari truth. In the United States, the salty Japanese condiment is a common household seasoning agent and savior for gluten-free adherents and chefs looking to appease them. It has no air of rarity or regional specialty—it’s right there next to the soy sauce and teriyaki sauce in just about every mainstream supermarket across the country. So what was going on—were we even talking about the same product? Had I stumbled upon tamari in the midst of an identity crisis? Or did it mean two very different things to different groups? As it turned out, the word “tamari” has meant many things over time. And in the process of untangling this mystery, I learned just how varied the many types of soy sauces throughout Japan are—to say nothing of soy sauces made in other countries or parts of the world—thanks to their ingredient composition, regional tradition, and terroir. Yet at a time when birth rates in Japan are low and industrialization has made carrying on these traditions more and more precarious, we may not get to experience them for much longer.

Tamari, or, to be clear, the old-fashioned style of tamari, is usually called tamari-joyu in Japan. Kohei Yamato, the fifth-generation owner of Yamato Shoyu & Miso, explained that producing it is a long and laborious process, requiring three years to ferment. The high price tag of each bottle reflects this. Made from primarily soybeans, it’s thicker in body and used as a finishing sauce rather than for cooking. Therefore it’s less versatile than shoyu, the style of soy sauce that has dominated Japanese tables since the Edo period. Tamari-joyu reflects an earlier stage of soy sauce making in the country, which some say was the origin of later soy sauce varieties.

“It is the original soy sauce,” says Sonoko Sakai, a California-based Japanese cooking instructor and author of cookbooks including Wafu Cooking, during a recent phone conversation.

The Japanese started using tamari in the Muromachi period, in the 12th to 13th century, she says, when it was found to be a tasty by-product of miso making. Liquid would accumulate at the bottom of the miso barrel (the word “tamari” translates to “puddle”), and it tasted good, so it began to be used for seasoning foods. Brushed on grilled fish, poured into soups, and added to marinades, the liquid was more adaptable to a range of uses than miso. Sakai was unaware of this history until she began making her own miso at home. She was also largely unaware of tamari—though she’d lived in Tokyo during her childhood, her family never had tamari in the kitchen, only shoyu, and they also didn’t make miso paste. But now she calls the few ounces of tamari she gets from a homemade batch the best part of making miso.

“It’s such a beautiful dark amber liquid that is basically, for me, a jewel,” says Sakai.

When teaching classes, she lets her students taste a spoonful to experience how different it is from soy sauce: “It has a rounder flavor, it’s deeper in color, and even the fragrance, when you bring it to your nose, it has a harmony,” says Sakai.

When collaborating on a soba pop-up dinner with Los Angeles chef Travis Lett years ago, Sakai was trying to figure out how to make a suitable dipping sauce that was gluten-free, to be accessible to those with dietary restrictions. Her go-to shoyu soy sauces wouldn’t cut it, but she was surprised to find that the budget allowed for high-quality tamari-joyu from Japan, which cost around $40 per 500-milliliter bottle. She went with Ito Shoten brand tamari from Aichi prefecture, which is imported by the e-commerce brand The Japanese Pantry.

Ito Shoten is a 200-year-old tamari and miso brewery that’s currently helmed by its octogenarian ninth-generation owner along with his grandson, who represents the eleventh generation in this family business. (In Japan, it’s customary for the first son in a family to carry on his father’s business). According to Chris Bonomo, cofounder of the Japanese Pantry, its tamari is aged for three years in centuries-old wooden barrels weighed down by river stones as part of the family’s uncompromising approach to their traditional craft. It’s one of the most expensive condiments by weight on the Japanese Pantry’s retail site, he says, but also one of the most exquisite.

“When you pour it, you’ll understand—it’s thick,” says Bonomo. “It’s like the difference between 25-year-aged balsamic vinegar and the balsamic vinegar you can get at Trader Joe’s.”

You’ll want to highlight this tamari by brushing it on grilled meats or sashimi rather than muddy it by incorporating it in your ramen broth, he says. This tamari is emblematic of the cuisine of the Chubu region, where Aichi prefecture sits, in that it packs a deep and powerful umami punch.

“Nothing against Kikkoman—they’ve done amazing work over the last 50 years here, and not everyone can use three-year-aged tamari,” says Bonomo. “But just try it, and you’ll see.”

Before I got to try Ito Shoten’s product for myself, I had to reassess my whole understanding of tamari and how it was made—a process exacerbated by a week of largely sleepless nights brought on by Tokyo–to–New York jet lag. At the same time that these puddles of miso were being carefully collected by octogenarian artisans, weren’t fast-casual chains buying it in bulk to make gluten-free rice bowls? I wondered. And wasn’t tamari more popular in the United States than ever, thanks to the popularity of “GF” dining options on menus and product labels?

What “tamari” means to you largely depends on where you live and when. If you came of age in the United States somewhere around the turn of the millennium, then you probably think of tamari as a gluten-free soy sauce substitute. Gluten-free dieting—whether due to celiac disease, gastrointestinal discomfort, or other preferences—only became a widespread cultural phenomenon in the early 2000s, with blogs such as Gluten-Free Girl. If you’re older and from the back-to-the-land or natural foods movements, then you probably think of tamari as your go-to type of soy sauce because it was written about in books and recipes from the macrobiotic movement.

According to William Shurtleff, who, along with Akiko Aoyagi, coauthored popular books including The Book of Tofu and The Book of Miso in the 1970s, the term “tamari” was chosen to describe naturally fermented soy sauces from Japan by George Ohsawa, founder of the macrobiotic diet in America. This was because he wanted a word to distinguish them from hydrolyzed vegetable protein, a cheaper chemical process used to make soy sauces from brands like La Choy, which was becoming prevalent in the United States.

But Shurtleff said that Ohsawa made a mistake in picking the word “tamari,” since the term applied to just one type of Japanese soy sauce that’s made with little or no wheat. Shurtleff and Aoyagi went on to campaign for the term “shoyu” to be favored for Japanese soy sauces, which is described in their 2012 book History of Soy Sauce. However, Kikkoman—the biggest brand for soy sauce in the United States—never stopped labeling its product “soy sauce” rather than “shoyu,” even though it is a wheat- and soy-based shoyu soy sauce. Meanwhile, the US demand for tamari created inroads for the Japanese tamari brand San-Jirushi. The company is based in Mie prefecture, where it began making tamari and miso in 1804. When it launched in the United States in 1978, the brand name was shortened to San-J for ease. In 1987, the company built the first tamari soy sauce brewery in the United States in Richmond, Virginia, to supply the growing US market.

Takashi Sato is an eighth-generation member of the family that founded San-Jirushi and the current CEO of its US-based operations. Sato’s cousin is the CEO of the company in Japan. This is because Sato’s father was not the first but the second son, and he only came to sell tamari as a second career. While working for Toyota Motor Corporation, Sato’s father often traveled to the United States for work. There he would entertain visitors at Benihana, which was founded by his childhood friend Rocky Aoki. He saw the growing enthusiasm for Japanese cuisine in the country and felt the opportunity was ripe for high-quality tamari soy sauces in America. He also leaned into the hippie movement by hiring salespeople who were very much part of that lifestyle.

“My father did not want to sell soy sauce to Japanese living in America; he wanted all Americans living in America to enjoy soy sauce,” says Sato.

As the son of a second son, Sato says he didn’t have any obligation to join the family business. But after working for the Japanese conglomerate Ajinomoto, he decided he liked the food sector and eventually took over the US branch of San-J in 2001. Today San-J produces around 10 million bottles of tamari per year, which are sold throughout the United States, Canada, Europe, New Zealand, and Mexico. It’s found in national chain supermarkets including Whole Foods Market, Publix, and Target.

Tamari products account for more than 90% of San-J’s sales, both in the United States and in Japan, although the company does sell some shoyu. Organic tamari is the best-selling product from San-J in the United States, and sales have been growing every year. When I asked Sato if this tamari was any different from the product the brand sold in 1804, he replied that the basic manufacturing process was the same, although it has been thoroughly modernized. Stainless-steel barrels have replaced wooden ones, and machines have replaced some manual labor.

“Of course, tradition is important, and I respect my ancestors. However, I do not believe the way we did things in the past is always the best. We are always looking for ways to improve,” says Sato.

That said, Sato revealed that San-J is currently working on launching a “Tamari Maniac” line that will feature a much darker, more umami tamari that’s more labor-intensive to make. Sato is also a fermentation geek himself—active on social media, he has shared a pumpkin amazake recipe and encouraged followers to use their leftover Halloween pumpkins for other fermentation projects.

“Fermentation is a method that can be applied to any raw material,” he tells me. “So if there are crops that are indigenous to the area, why not use them to create a new version of tamari? Tamari made with corn from Minnesota, tamari made with seaweed from California, with rice from Arkansas, and so on.”

A more recent product in San-J’s US lineup is a “no-soy” tamari made with pea proteins. It was introduced three years ago to cater to people with soy allergies. In fact, much of San-J’s US marketing caters to food allergies, with an article on “gluten-free holiday menu ideas” currently featured on its homepage.

When I reached him by email, I asked Shurtleff if he still thought Ohsawa had made an error in using the term “tamari,” since nowadays many people do recognize the condiment as a wheat-free (or almost wheat-free) alternative type of soy sauce. Perhaps inadvertently, Ohsawa had introduced a product that more and more people have connected with in the United States and beyond despite being a regional rarity in Japan. Yes, Shurtleff responded, he did still think it was a mistake. But “most soy sauce sold in the US today and labeled ‘tamari’ contains little or no wheat,” he wrote. That was not always the case back when the term was first picked up.

Oddly, though, when tamari-joyu is enjoyed in Japan, it’s not because of its lack (or near lack) of wheat. That’s because “gluten-free” just isn’t as much of a thing there. It’s enjoyed for its distinct flavor, its rich body, and all the things that make it different from, well, all the other types of soy sauce—from shiro shoyu, made from around 90 percent wheat and 10 percent soybeans for a sweeter flavor, to hishio, a raw soy sauce with living enzymes. The latter is produced at Yamato Shoyu & Miso, in Ono port, and imported to the US market through the retailer Japanese Taste.

While on the “fermentour” at Yamato’s brewery, I asked Kohei Yamato, the fifth-generation brewer, what he thought of tamari. He wasn’t personally a big fan, finding its intensity less versatile than shoyu. But his company had recently launched its own version of tamari, which is currently only available in Japan. It took him years to develop, and he ended up using a combination of soybeans and rice to perfect the formula to his taste while keeping the product gluten-free. And why did he make it? I asked.

“It’s like the difference between 25-year-aged balsamic vinegar and the balsamic vinegar you can get at Trader Joe’s.”

He made a swinging motion with one arm. “Djokovic,” he finally said, after trying the syllables out a few times. Novak Djokovic, the Serbian 24-time Grand Slam–winning tennis player and staunch gluten-free dieter, had once shared on social media a recipe that called for tamari, Yamato recalled. That got him thinking that there was an opportunity he was missing out on. People around the world were looking for tamari, and here there were only a few brands they could get it from. Even though Yamato is a very small operation, employing only 29 people in its 3,900-square-foot facility, he hopes that more of its products can make it to overseas markets in the future. Making tamari could help, he thought.

A couple weeks after returning home from Japan, my Ito Shoten tamari arrived in the mail from the Japanese Pantry. It was wrapped with more than twice its bulk in taped-up bubble wrap, which took a while to free with scissors. The bottle is squat and small, more resembling a perfume bottle than the typical tall and skinny soy sauce bottle, which I’ve been known to use as a dumpling dough roller.

Roll the bottle in your palm, and the liquid clings to the glass a bit longer than most soy sauces. Yet it’s not quite as dark and viscous as Chinese dark soy sauce, a product that often has sugar or molasses added to it. I poured a little onto a spoon. The color is deep mahogany. The aroma is husky and big—like dark roasted nuts with leather and chocolate. And it tastes wonderful—intensely salty and caramel and umami. It’s a taste you’ll want to savor brushed on a nice piece of fish, as Sonoko had recommended. But a little goes a long way. I could barely finish the few droplets on my spoon.

To be sure, I then tasted the San-J organic tamari, what Americans might consider the standard-bearer for the condiment as we know it. It was delicious, if sweeter and lighter, and ready to drizzle liberally into a wok while stir-frying. When I gave a blind taste test to my husband (who, as far as I’m aware, has virtually no experience with tamari, especially slurped by itself from a spoon), he actually preferred the San-J.

I also ordered the hishio raw soy sauce from Yamato (via Japanese Taste, although I could have bought it at the factory in Japan, had I been willing to lug glass bottles around while traveling). It’s bright, fruity, floral, elegant, and different enough from the others to taste like an entirely distinct condiment. The three soy sauces I held in front of me—tamari-joyu, mass-produced tamari, and hishio shoyu—tasted as different from one another as, say, pineapple juice, red wine, and root beer. So why shouldn’t the category of tamari itself—the old, the new, the mass-produced, the artisanal, the gluten-free, the soy-free—have many different flavors within it? I’m personally here for all of them. And that means keeping the old ones around.

It took a while to understand that, just as with shoyu, today there are some artisanal outfits carrying on centuries of tradition to make tamari, and there are mass-produced versions, from brands who went big, like Kikkoman and San-J. Tamari simply took an unlikely path to global renown through the United States’ hippie movement and food intolerances.

“It used to be that every region made soy sauce, even in homes,” says Sakai. It’s sad, she says, because the local flavors and nuances are becoming obscured through industrialization. To preserve the diversity in Japanese condiments, she says we need to support the families making them the artisanal way, before they disappear. That’s especially true for traditional tamari.

“People in Japan say that you can use [tamari-joyu] as a salt substitute, but I rarely use it that way because it’s so expensive,” says Sakai. “But maybe I should.”