Yamaroku Soy Sauce

Yamaroku Soy Sauce


A fifth generation soy sauce brewer and master builder of the large wooden barrels (kioke) traditionally used in Japan to ferment foods, Yasuo Yamamoto is proving the flavor benefits of the kioke barrels by the deep, dark overwhelming savoriness of the classic style of soy sauce that he is making with them at Yamaroku Soy Sauce.


During the Edo period (1603-1868), the islands and coast of the Seto Inland Sea became food manufacturing centers for the rest of the country. Once a center of Japan’s original Pacific island culture and a vibrant maritime world, the region had come to be valued mainly for its raw food materials and sea transportation lanes. First was the essential ingredient of sea salt, which was mass produced on large enden salt fields starting in the 17th century at places like the town of Takehara in Hiroshima prefecture, where wide differences in the tides enabled the cheap and efficient harvesting of salt from the sea. Next came a different kind of indispensable food—sake. Because of the revolutionary development of big wooden barrels, called kioke, sake could be brewed on a large scale for the first time (it had previously been made in small clay pots), and a cluster of breweries soon began making sake near the excellent spring waters and rice fields of the Nada district, which is on the Seto Inland Sea shores of Hyogo prefecture. Finished foodstuffs were loaded onto barges and shipped to the new capital at Edo-Tokyo and other major cities in the north, where the political and social power of the country now resided.

The third major food making industry to be established in the Seto Inland Sea region was soy sauce on Shodoshima Island. By the beginning of the 17th century, Japan's food makers had refined the recipe for soy sauce, adapting it to Japanese tastes so that it was more appetizingly aromatic and subtly flavored than the original Chinese version. It also had other benefits. As a diluted form of liquid salt, it was cheaper than dry granular salt and became an alternative to salt in preserving and pickling foods. In addition, its complete combination of flavors—salty, acidic, sweet, and especially its rich, mouth-satisfying umami—made it a handy all-purpose seasoning for cooking and finishing foods at the table. Soy sauce quickly became a popular seasoning among Japan’s large, fast-growing, and urbanizing population. To meet demand, an industry of soy sauce breweries was established on Shodoshima Island, re-using the big wooden barrels that the sake brewers across the straits at Nada had discarded after thirty years of use. In addition to enabling the mass production of soy sauce, the kioke barrels turned out to be much more important to brewing soy sauce than sake. For one thing, soy sauce brewers could use them for one-hundred and more years versus only thirty years for sake. More importantly, the beneficial bacteria that lived in the barrel’s wood grain were key to developing soy sauce’s deep, rich savory flavor (its umami) over the long two-year fermentation period required to make high quality soy sauce. Good sake, on the other hand, is fermented for a much shorter thirty to forty-five days, making the type of vessel in which it is brewed less important.

Shodoshima was the leading producer of soy sauce for much of the Edo period. As the second largest island in the Seto Inland Sea, it was a major producer of sea salt and also had large reserves of fresh water (two of soy sauce's essential ingredients.) And the island was conveniently located in the sea’s major transportation lanes, providing easy access to shipments of soy beans and wheat (soy sauce’s other two main ingredients) grown in the region and enabling shipments of finished soy sauce onwards. At its peak, there were hundreds of soy sauce breweries using thousands of kioke barrels on Shodoshima. Over time, the island's breweries were superceded by soy sauce makers operating north of Edo-Tokyo. (Soy sauce has always been a more popular seasoning in cold, northern Japan partly because the region cannot easily produce natural sea salt.) But even today Shodoshima has the largest number of kioke barrels in the industry—1,000 out of the estimated 3,000 still in use to make soy sauce. Unfortunately, many of the local brewers have compromised the quality of their product by using denatured soybean meal imported from the U.S. and Canada, which has been stripped of its oil and much of its nutrients, and/or are shortening the fermentation time to less than the two years needed to make deeply savory soy sauce. There is one local brewer that stands out. Yasuo Yamamoto at Yamaroku Soy Sauce is making soy sauce the old-fashioned way with high quality, all-natural ingredients and a long fermentation period. What’s more he is leading a nation-wide effort to renew the craft of making kioke barrels and assert their role as a key ingredient in making fine soy sauce. Yasuo is demonstrating the importance of kioke barrels by relying on them and the beneficial bacteria that live within them to make a uniquely flavored, classic style of soy sauce that has deep and delicious layers of umami richness.

Shodoshima is a dramatically beautifully island composed of of rugged granite mountains and an intricately articulated coastline of coves, inlets, and winding peninsulas. The island's cluster of soy sauce brewers is located at the base of the mountains in the upper left corner of the photograph.

Yasuo Yamamoto, the fifh generation maker of Yamaroku soy sauce, in his brewery.

The kioke at Yamaroku are 2 meters high and 2 meters and 30 centimeters wide and hold 5,700 liters of moromi, the fermenting mash of soy beans, wheat, sea salt, and water. Some of the kioke are more than seventy-five years old.

Soy Sauce That Is Made in the Barrel

Yamaroku is located in a warren of narrow lanes lined with impressive stone walls made of the granite seen in the rugged mountains that rise up behind the brewery. There are other soy sauce makers in the quiet residential neighborhood, but the island’s large commercial ones, including Marukin, the fifth largest producer in Japan, are based south, down in the busy town of Shodoshima, which is on the shore of Uchinomi Bay in a theme park area called Soy Sauce Village. Yamaroku is a smaller, much more traditional operation than these, and its sixty-six wooden barrels are housed in a shed next to the family house. The business was started about 150 years ago, and Yasuo is the fifth generation of the family to make soy sauce. He is a passionate artisan who does everything himself by hand. But he does not think he is working alone. There are three-hundred different kind of spores of beneficial bacteria living in the brewery—in the ancient kioke barrels, in the wooden decks corralling them, and in the walls, beams, and roof of the building—and he considers them to be the true agents brewing the soy sauce and giving it its deep, rich flavor. He believes his role is to nurture and care for them. His job is to supply them with the best soy beans, wheat, sea salt, and water and also the kioke barrels in which to live and work their fermentation magic, and intervene in the process of making soy sauce as little as possible.

Yasuo begins making new soy sauce each winter, from November to March, when the cool air is pure and the low temperatures allow the spores to start working slowly and gently. His philosophy that great soy sauce should be what nature intended, and not the handiwork of the brewer, is reflected in every step of his process. First he makes the koji starter, mixing steamed soy beans and roasted wheat with koji-kin mold (Aspergillus oryzae), and leaving this mixture to bloom for two days, not touching it. Soy sauce brewers typically mature their koji for three to four days, raking and fluffing it all the while and manipulating it with other house-developed techniques. After two days, Yasuo mixes the koji with sea salt and water in the kioke barrels, creating the main fermentation mash called moromi, and, again, lets the spores go about their business for the next few months. Aware that they are living things, he goes to the brewery every day “to greet and talk to them.” He says that they, in turn, “know that someone is there.” Lactic acid fermentation takes place during this first phase of soy sauce brewing, and the shed is filled with the aroma of apples, bananas, and melons. In the spring when the weather warms up the yeasts come out, and Yasuo stirs the moromi from time to time to give the yeasts air and help them grow. By summer, the smell of chocolate fills the shed, and Yasuo paddles the moromi more regularly to support the vigorous fermentation of both lactic acids and yeasts.

When winter returns, the spores quiet down again. The moromi is left in the barrels to go through at least one more vigorous summer fermentation. During this time full saccharanization occurs, and the smell of liquor overwhelms all other smells. At the end of the second year, Yasuo knows the soy sauce is done by looking at it. He filters and presses the moromi using an old machine, squeezing out every last drop of soy sauce from the mash to gather all of its flavor and richness. Other artisanal brewers may lightly drip the soy sauce or press the mash to less than 100% to create a more refined product. Yasuo then pasteurizes the soy sauce at a relatively low 70-72 degrees in winter and 69-70 degrees in summer to stabilize it yet preserve as much of the flavors created by the spores as possible. As soon as the soy sauce reaches these temperatures, he cuts the heat. The soy sauce is ready to be bottled.

Each winter, in late January, after the new batches of soy sauce have been laid and the old ones have entered their somnolence, Yasuo makes kioke barrels, and the barrels he makes for himself and other soy sauce brewers is helping to save the tradition of making high quality soy sauce. The barrels in use in Japan today have an average age of seventy-five years and can be used for at most another fifty years. In addition, their numbers have been declining because most fermented food makers switched to using more efficient steel tanks during the last century. As a consequence, there are only two manufacturers of kioke barrels left in the country and their master barrel makers are getting old. In 2012, Yasuo apprenticed himself to one of these, Takeshi Ueshiba of Fujii Wood Work in Sakai, Osaka prefecture. The next year he began making barrels himself in back of his shed, and since then has been holding an annual winter event during which volunteers from across the country come to help and learn from him. His impact has been remarkable. In addition to renewing his stock of kioke barrels and ensuring the future of Yamaroku’s soy sauce, he has raised the awareness of the importance of the kioke barrels as a key tool and ingredient in making high quality fermented foods because of the millions of beneficial bacteria they harbor. Other artisanal makers of soy sauce, sake, mirin, vinegar, and miso among other fermented foods have been inspired by him and are increasing their use of kioke barrels in their processes. And by sharing his barrel-making know-how, he has spawned a growing number of barrel makers at other small fermented food businesses, fostering a virtuous cycle of renewal and expansion of making high quality fermented seasonings in Japan.

Black walls at soy sauce breweries, like these at Yamaroku, are a sign of a prosperous business. The bacteria that create the color are the "good" bacteria needed to ferment soy sauce. It also means the brewery is busy as the color immediately dissipates when business slows down or is stopped.

The entrance to the main area of the Yamaroku brewery where the kioke barrels are fermenting the moromi.

In addition to appetizing aromas, the soy sauce brewery is filled with soft burbling sounds as the spores throughout the building ferment the moromi.

The old mechanical press that Yasuo uses to squeeze out every last drop of soy sauce from the bottom of the barrels of moromi.

The chocolatey color and texture of one-year-old moromi.

"Hishio"—the Ancient Name for Soy Sauce

Yamaroku makes a very limited product line reflecting Yasuo’s belief that nature makes soy sauce not him and that there is only one type of soy sauce—the long fermentation of soy beans, wheat, salt, and water. There is a traditional koikuchi soy sauce and a double-fermented and extra long-aged saishikomi soy sauce. Although the flavor of Yasuo’s soy sauce changes each year, sometimes in subtle ways, sometimes in more significant ones, he knows how to blend the batches to create consistent flavor. 

Yasuo’s koikuchi type soy sauce is called “Kiku-Bishio.” ("Bishio" is a derivation of "hishio," which is the ancient name for soy sauce.) Aged for a traditional two to two and half years, it is made with some of the best heirloom soy beans in Japan, marudaizu kuro-mame (whole, big, round black soy beans) from the Tamba-Sasayama area west of Kyoto, which is famous for growing the best soy beans in the country. They are rich, creamy, buttery beans that transcend the “beany” taste of most soy beans, while also being especially high in nutrients. They are so flavorful and prized that they are served simply boiled as a featured food during New Year’s celebrations. Yasuo gets them from Odagaki Shoten and Kane-zan, two shops that have been growing their beans for centuries and are known for they way they nurture their plants and hand pick their beans. The wheat used is locally grown in Kagawa prefecture, the sea salt is natural, and the wild, microbe-laden water comes untreated from a well on the property as was the practice for soy sauce makers in the old days.

“Kiku-Bishio” is an exceptionally well-made, classic style soy sauce with a rich blood-red color, agreeably sharp saltiness (the enbun, or salt ratio, is 14.5%), and deep layers of umami. It has a unique taste of place because of the flavors imparted by the spores in the air, water, kioke barrels, and bones of the building, but it is not the taste of the delicate, light, balanced cuisine of the region. Yasuo continues the Shodoshima tradition of brewing a soy sauce for the strong, rich tastes of northern Japan, where the island’s soy sauce was shipped to in centuries past. “Kiku-Bishio” should be used for cooking, where its saltiness, deep umami, and unique taste can enhance and enrich food and add complexity and depth of flavor to dishes. In soy sauce’s most traditional way, it can be used to pickle and preserve foods. It can also add aroma and flavor to foods like grilled fish and roasted vegetables. Lastly, one teaspoon of “Kiku-Bishio” is perfect for adding a kakushi-aji (a secret seasoning or hidden taste) to long-braised dishes.

The other soy sauce that Yasuo makes is a finishing soy sauce to add aroma, color, and flavor to foods at the table, or in the very last seconds of cooking. It is called “Tsuru-Bishio” and is a double-fermented, extra long-aged saishikomi type of soy sauce. To make it Yasuo takes two-year-old soy sauce and blends it with new moromi and then ages everything for another two years. Most makers of this type of soy sauce age it for only three years in total. The soy beans are the hybrid Enrei from Toyama prefecture in Japan’s northern Hokuriku region. The wheat is the hybrid Haruyutaka and is also grown in the north, in Hokkaido. Both are hardy hybrids with lots of umami-producing protein and gluten. They have the strength to stand up to long fermentation, which works to bring out their best flavor.

“Tsuru-Bishio” is very dark, almost black, and is very rich, creamy, and slightly sweet and alcoholic. The enbun is a lower 13.8%. It is a delicious soy sauce, and its rich, sweet, fruity aroma makes you hungry while its deep umami flavor makes you want to eat it by itself. “Tsuru-Bishio” gives richness to delicate yet full flavored foods like tofu and steamed fish. It can also be used on sashimi and goes best with strong flavored ao-zakana fish, which are rich and fatty, blue-backed types of fish. It can also be drizzled on salads, cheese, roasted vegetables, and grilled meats and is a great topping for desserts— puddings, ice cream, and cheesecake—when its mild saltiness and acidity enhances such rich, sweet dishes. Yasuo makes a ki-age (unpasteurized) version of this soy sauce. The difference is the ki-age type has a wilder taste and gives a quick hit of umami, while the unpasteurized type has a softer, slower aroma and its flavor dissipates more gradually in the mouth.

Yasuo makes two versatile blended sauces. One is a classic, very well-made ponzu that blends Yamaroku soy sauce with a full range of some of the best seasonings in Japan, including yuzu and sudachi citrus from Kochi prefecture, brown cane sugar from Tanegashima Island, soft, fragrant, rich rausu-konbu seaweed from Hokkaido, and rich soda-katsuo (mackerel tuna) dashi from Kochi. (Most dashi in Japan is made from the lighter-tasting, more common bonito, or skipjack tuna.) Unlike standard ponzu, which simply is a light, refreshing salty-citrus condiment, Yamaroku’s ponzu is a full-flavored sauce that combines all the seasoning elements of salt, acid, sugar, and umami. Like ponzu it can be used on tofu, salads, pickles, and as a dipping sauce for lightly-simmered vegetables and meats. Because of its full body, all-purpose flavorings, and deep umami, it can also be used as a kakushi-aji for soups, stews, curries, and other braised dishes like Japanese nitsuke, oden, and sukiyaki and similar types of braised Western dishes, as a dipping sauce for heavier foods like gyoza dumplings, and as a glaze for teriyaki and marinade for all types of barbecues.

The other blended sauce, called “Hishio Tomato Sauce,” is a similarly rich and deeply flavored sauce that uses a principal Western culinary source of umami—tomatoes—as its base. The tomatoes are a special kind called “Hishio Tomatoes” that are locally-grown by a farmer who uses Yamaroku’s shoyu-kasu (the lees leftover from making soy sauce) as fertilizer for the plants, which heightens the tomatoes’ rich, sweet flavor. Yasuo presses the tomatoes at his brewery and then combines them with Yamaroku’s intensely rich and slightly sweet “Tsuru-bishio” soy sauce and adds sugar, apple vinegar, spices, and garlic to create a fully-flavored, thick sauce that is sweet, spicy, and hot, in addition to packing a strong umami punch. The sauce can be used as a condiment like ketchup on omelets and hamburgers, as a kakushi-aji in Bloody Mary’s, cocktail sauce, gazpacho, salsa, sweet-sour stir fries, and pasta dishes, and as a marinade and glaze for all kinds of Asian and Western barbecues. It is especially good on chicken and pork. This is a limited edition product that is only available in the fall after the tomatoes are freshly harvested.

From left to right: a small bottle of ki-age unpasteurized "Tsuru-bishio" saishikomi soy sauce, large bottle of pasteurized "Tsuru-bishio" soy sauce, and a large bottle of "Kiku-bishio" koikuchi soy sauce.


Story & Photos: Tom Schiller

A kioke wooden barrel laying on its side in front of the Yamamoto family house gives visitors a sense of the large size of the barrels used to make artisanal soy sauce. The shed in which Yamaroku's soy sauce is made is on the right.

Yamaroku Soy Sauce ヤマロク醤油
1607 甲 Yasuda, Shozu-cho, Shodoshima, Kagawa Prefecture 761-4411
Tel: +81 (0879) 82 0666
Web: http://yama-roku.net

Reflecting his passion and commitment to help people appreciate the craft and flavor of well-made soy sauce, Yasuo Yamamoto has made Yamaroku a delightful place to visit. At a small shop at the entrance, you can taste and buy Yamaroku's products. There are also stools and tables where you can have tea and soy sauce flavored snacks and desserts, such as soy sauce roasted rice cakes, soy sauce pudding, and ice cream topped with soy sauce. In addition, Yasuo will gladly take you on a tour inside the brewery and, depending on what he is doing that day, let you watch him fill the barrels, paddle and aerate the moromi, or press and filter the soy sauce. He only speaks Japanese but that doesn't stop him if you don't know the language. The brewery is open every day from 9:00 to 17:00 all year round.

Custard ice cream topped with Yamaroku's "Tsuru-bishio" four year-aged soy sauce and large, sweet black soy beans .


Getting There

There are several ports on Honshu Island and also one on Shikoku Island that provide ferry boat service to Shodoshima. Where you start from and where you get off on the island depends on your travel itinerary. Having said that, the most convenient way to get to Shodoshima is by boat from the port of Takamatsu on Shikoku Island even if it means traveling an extra distance to get to Takamatsu to do this. The train and bus terminals at Takamatsu are next to the ferry boat terminal (which is not the case for several of the starting points on Honshu Island). In addition, Takamatsu offers both standard one-hour ferry boat rides and a much faster 30-minute option to Shodoshima. Ferries from Takamatsu will take you to a number of ports there. The one that goes to the town of Kusakabe is very near to the area of the island where Yamaroku is located. From Kusakabe port it is a short bus or taxi ride to Yamaroku. You may be dropped off somewhere short of the brewery because of the narrowness of the neighborhood's streets. That's fine because the route is well-marked and the area is worth walking through because of its Shinto shrines, Buddhist temples, other old soy sauce makers, and charming lanes.

Early morning arrival at the ferry terminal on Shodoshima Island.

Eikoji Temple located near the Yamaroku soy sauce brewery with Mount Senbagagoku in the distance.

The characteristic rock walls of Shodoshima are made from the island's abundant granite, which was used to build Osaka and other castles in the 16th and 17th centuries.

"Kioke-kai" Barrel-Making Event

Each year in late January, after the rush of creating the new season's batch of soy sauce in late fall is over, Yasuo makes several new kioke barrels for himself and other fermented food makers. Anyone can join him in the community tradition of helping a neighbor with a big project. Equally important, it is a way for Yasuo to share his know-how of barrel making with others. Dozens of people show up each year for as many days as they are able, and the group typically includes carpenters, fermented food makers, artists, designers, and students from all over Japan. Increasingly, there are also film crews from Japan and abroad. Although Yasuo is intensely busy, he and his team will take time to show you how you can help split bamboo to create the braiding that holds the kioke barrels together, plane and miter the cedar planks, carve the wooden pins that hold the planks together, and lend a general hand of support. The rewards, in addition to a fascinating learning experience and great camaraderie, are a delicious home-cooked lunch and the chance to sign your name, in time-honored tradition, on the edge of a plank of one of the new kioke barrels.

Shodoshima Island

Shodoshima has a lot to offer. In addition to soy sauce, the island is famous for its somen noodles, sesame seeds, and world-class olive oil—a food business that was started in the early 20th century. Artisanal sea salt makers like Namihanado Sea Salt have also revived the tradition of making high quality sea salt on the island. There are also great restaurants and traditional inns, hiking trails and bicycle paths, sparkling beaches, and beautiful seasonal landscapes (the island is especially famous for its fall foliage.) Shodoshima is part of the Setouchi Triennale, which is a contemporary arts festival that was set up in 2010 and is being held every three years. The most recent festival held in 2016 featured over 150 artworks and installations by artists from both Japan and overseas. The Triennale lasts for eight months from March to early November. Next door to Shodoshima on the neighboring islands of Teshima, Inujima, and Naoshima are the annual arts activities sponsored by Benesse Art Site Naoshima. If you plan to visit these, you might consider staying on Shodoshima because it has a much wider range of places to stay and eat.

Soy Sauce Village

Many of Shodoshima's soy sauce makers are clustered at the southern end of the town of Shodoshima. Called Soy Sauce Village, the area is a unique collection of old industrial architecture, and the delightful experience of walking through it is heightened by the irresistible aroma of soy sauce brewing. A number of brewers have museums, exhibitions, tours, and tastings, providing a crash-course in the history, production methods, diverse flavors, and uses of soy sauce.  

"Twenty-four Eyes" Movie Village

Located at the tip of the peninsula south of the town of Shodoshima is a compound of buildings that were used as the set for the 1954 Japanese movie classic “Twenty-four Eyes.” Directed by Keisuke Kinoshita and starring his wife Hideko Takamine—both silver screen legends—the film is one of the most awarded movies in Japanese history. It is a melodramatic story spanning two decades in the lives of an elementary school teacher and her twelve schoolchildren during the turbulent times leading up to and immediately after World War II. The movie is worth watching for its scenes of Shodoshima's way of life in the first half of the 20th century. At the movie village you can enjoy a lunch of the island's famous somen noodles and take in windswept views of the island and surrounding Seto Inland Sea.

The Fishermen of Ine

The Fishermen of Ine

Imada Shuzo's Ginjo Sake

Imada Shuzo's Ginjo Sake