Okamoto Soy Sauce
The Okamoto Family (left to right): Yoshifumi, Yoshihiro, Teruko, and Tetsuya.
For nearly one-hundred years, the Okamoto family has been brewing a uniquely flavored, all-natural soy sauce on Osaki Kamijima Island, a large island located in the western half of the Seto Inland Sea known for its agricultural and artisanal foods. The soy sauce that Okamoto makes—delightfully fragrant with a mellow richness, slightly sweet flavor, and medium body—is perfectly suited to the region’s home cooking. It adds depth of flavor to dishes, but its umami does not overwhelm the fresh, natural flavors of the main ingredients, many of which are seafoods.
Today, the brothers Yoshifumi and Tetsuya lead the brewing process. They benefit from the guidance and hands-on support from their father Yoshihiro. A spry octogenarian who learned how to make soy sauce from his father and also from his grandfather who founded the small family business, Yoshihiro has helped ensure that Okamoto adheres to traditional brewing methods and the original family recipe.
Still, Yoshihiro gives much of the credit for the distinctive flavor of Okamoto’s soy sauce to nature. This includes the green tane-koji mold seeds (Aspergillus oryzae) dusted on the prepared soy beans and wheat to help them ferment, the beneficial micro-organisms that live in the brewery and large kioke wooden barrels in which the soy sauce ferments (many of which are as old as the brewery), and the mineral-laden breezes that flow into the brewery from the Seto Inland Sea in front of the building and the pure mountain air passing through it from behind. He also tells you that nature’s work includes the influence of the seasons as the soy sauce ferments and ages over time, which ranges from one to three years depending on the type of soy sauce.
Ferries run regularly to Osaki Kamijima Island from Takehara City on mainland Honshu Island. Okamoto Soy Sauce is located across the street from the port of Shiromizu.
At the entrance to the brewery you can buy Okamoto’s soy sauce and related products and also begin a tour of the brewery.
While it’s true that these factors are essential to the quality and nuanced flavor of the kind of naturally-brewed soy sauce the Okamoto family makes, Yoshihiro is being modest. The unique taste of place of Okamoto soy sauce also reflects careful choices, skill, and hard work. The family only uses the best local ingredients. Protein-rich Akimaro soy beans and fragrant Minami no Kaori wheat come from the Shobara valley in the mountain highlands of Hiroshima prefecture on Honshu Island, located north of Osaki Kamijima across the Seto Inland Sea. The sea salt is harvested from along the shores of Shikoku Island, which lies south of Osaki Kamijima.
Yoshifumi and Tetsuya also point out that brewing soy sauce in harmony with nature is an art; one that relies on the five senses, for which their father is a living handbook. From him, they have learned how to judge the taste of the soy beans after they are steamed, the fragrance of the wheat once it’s roasted, and the sound, feel, and color of the soy sauce as it ferments and ages.
Every step of the brewing process at Okamoto is done by hand, with manual labor continuing even after each winter’s new batch of soy sauce is placed in the brewery’s thirty large barrels and left for time to work its magic. Every three days the brothers aerate it with long wooden poles called kaibo to help the soy sauce breathe.
When the soy sauce is ready to be bottled, the final step is extracting the soy sauce from the mash (called moromi) in the barrels. The Okamotos slowly press the moromi overnight and then carefully siphon off the soy bean and wheat oils floating on the surface. This process enhances the clarity, lightens the body, and highlights the nuanced flavor of Okamoto’s soy sauce.
Okamoto is the last remaining soy sauce brewery on Osaki Kamijima. At one time there were eleven brewers. That Okamoto continues to thrive is a testimony to both the quality of its soy sauce and the family’s dedication to providing its customers with soy sauce that supports their style of cooking—fresh foods simply prepared with just the right touch of added richness and flavor.
The Okamoto family’s commitment to making soy sauce in the old-time, authentic way is an encompassing one, and they act as mentors to artisanal brewers across the region, sharing their know-how to help these other brewers maintain sustainable businesses. The family also warmly welcomes visitors and will happily give you a tour of the brewery. Osaki Kamijima can be reached by ferry from several locations on Honshu and Shikoku islands. Okamoto Soy Sauce is located just across the street from the port of Shiromizu.
Okamoto Soy Sauce (岡本醤油醸造場)
2577 Higashino, Osaki Kamijima Island, Toyota District, Hiroshima Prefecture 725-2031
Tel: +81 (0846) 65 2041
Web: okamoto-shoyu.com
The brewery is open daily from 10:00 to 17:00. The Okamoto’s various types of soy sauce and related products are on display for sale at the entrance. If you’d like a tour, the Okamoto family recommends that you call ahead and make a reservation.
Where To Buy
Okamoto Soy Sauce is recognized as a premium artisanal soy sauce both in its region and across Japan. Locally, it can be found at supermarkets and souvenir shops. Elsewhere in Japan, look for it in the food halls of department stores and at specialty food shops in major cities. It’s also available at Hiroshima prefecture’s crafts and foods shop called “Tau’ located in the Ginza in Tokyo.
How To Use
Okamoto produces Japan’s three core soy sauces: koikuchi, usukuchi, and saishikomi, along with two complementary sauces, dashi-joyu and kabosu ponzu, which are crafted using their koikuchi soy sauce as a base. The Okamoto family’s suggested applications for these sauces are:
Left to right: Bottles of Okamoto’s usukuchi, saishikomi, and koikuchi soy sauce.
Koikuchi — Dark, “deep-tasting” soy sauce aged for two years to be used for making meat marinades, grilling foods, and in simmered and braised dishes that consist of a medley of ingredients with strong flavors.
Usukuchi — “Light-tasting” soy sauce aged for one year and used for marinating and cooking seafood and making vegetable dishes.
Saishikomi — An ultra-rich soy sauce because it has been double-brewed (a new batch of soy beans and wheat is mixed with raw koikuchi soy sauce instead of with water and sea salt) and matured for three years. The Okamotos recommend using saishikomi as a finishing sauce when a richer, stronger, sweeter flavored soy sauce is desired. For example, a few drops on tofu, sashimi, pickles, and lightly-cooked vegetable dishes, like ohitashi.
Dashi-Joyu — A versatile, all-purpose concentrated pre-mix of dashi stock and koikuchi soy sauce that can be used as a base seasoning for all kinds of dishes. The Okamotos recommend adding two to three parts water to one part dashi-joyu for marinades, simmered and braised dishes, and salad dressings. If using it to make a light soup stock, such as for udon noodles, they suggest adding nine to ten parts water for one part dashi-joyu. For a stronger broth, as in a nabe hot pot, their recommendation is to use three to four parts water for each part dashi-joyu. Dashi-joyu can also be used to make a yakiniku barbeque dipping sauce by mixing equal parts grated daikon radish and dashi-joyu.
Kabosu Ponzu — A unique ponzu sauce made from koikuchi soy sauce and kabosu citrus juice. Kabosu is the most traditional type of citrus used in home cooking in the western Setouchi region. It’s a native Japanese citrus that is related to yuzu, but is larger, juicier, and has its own special forest-like fragrance and flavor. Okamoto uses kabosu grown in Oita prefecture on Kyushu Island, which is known for producing the best kabosu in Japan. Like all ponzu sauce, it can be used to season dishes, make marinades, and as a salad dressing and dipping sauce.