Traditional Shodoshima Soy Sauce
LESS THAN 1%
The Traditional Soy Sauce Japan Once Knew
Traditional kioke-brewed soy sauce has become an exceptionally rare part of Japan’s food culture.
For centuries, wooden barrels known as kioke were used to ferment and mature many of the fundamental seasonings of Japanese cuisine. Today, this traditional way of making soy sauce survives only on a very small scale.
Yet on Shodoshima, an island in Japan’s Seto Inland Sea with more than four centuries of soy sauce-making history, the tradition still lives on.
The Taste Behind Washoku
In 2013, Washoku — traditional dietary cultures of the Japanese — was inscribed on UNESCO’s Representative List of the Intangible Cultural Heritage of Humanity.
At the foundation of Japanese cuisine are fermented seasonings that create its distinctive balance of aroma, umami and depth.
Among them, soy sauce is indispensable.
From sashimi and sushi to simmered dishes, grilled foods and everyday home cooking, soy sauce has helped define the taste of Japanese cuisine for generations.
But the way most soy sauce is produced today is very different from the traditional methods once widely used in Japan.
SINCE THE 1590s
More Than Four Centuries of Soy Sauce Brewing on Shodoshima
The history of soy sauce brewing on Shodoshima is believed to date back to the Bunroku era (1592–1595) — more than 400 years ago.
At the time, stone was being quarried on Shodoshima for the construction of Osaka Castle.
The quarrying parties who came to the island are said to have brought with them a prized seasoning from Yuasa in Kii Province, present-day Wakayama.
It was the flavorful liquid associated with Kinzanji miso, regarded as an important predecessor in the development of Japanese soy sauce.
Intrigued by this seasoning, people from Shodoshima are said to have travelled to Yuasa to learn the brewing methods, bringing that knowledge back to the island.
This is traditionally regarded as the beginning of Shodoshima’s soy sauce culture.
Why Shodoshima
Shodoshima already possessed something essential to soy sauce making:
salt.
Salt production had flourished on the island for centuries, while its position along the maritime routes of the Seto Inland Sea made it possible to bring soybeans and wheat to the island and later ship finished soy sauce to major markets such as Osaka.
The island’s warm, relatively dry climate also provided favorable conditions for koji development and the fermentation and maturation of moromi.
Salt. Sea routes. Climate. Fermentation.
Together, these conditions allowed soy sauce brewing to take deep root on Shodoshima and eventually become one of the island’s defining traditions.
Before Modern Production, There Was Kioke
Long before modern production tanks became standard, soy sauce was traditionally fermented and matured in large wooden barrels called kioke.
Soybeans, wheat, salt and koji are transformed through fermentation, guided not by speed, but by:
microorganisms, craftsmanship and time.
And the wooden barrel itself is far more than simply a container.
Over many years of brewing, yeasts, lactic acid bacteria and other microorganisms inhabit the wood, as well as the walls and beams of the brewery.
Each brewery develops its own microbial ecosystem, contributing distinctive aromas, depth, umami and character to the soy sauce produced there.
No two breweries are exactly alike.
What Was Once Ordinary Has Become Rare
Modern production brought greater efficiency, consistency and scale to soy sauce making.
But as production changed, traditional wooden kioke gradually disappeared.
What was once part of everyday Japanese fermentation culture has become something exceptional.
Shodoshima remains one of the most important places preserving this tradition, with more than 1,000 wooden kioke still found among the island’s soy sauce breweries.
This rarity was never created as a luxury.
It is rare because so little of the traditional method remains.
A Living Culture of Fermentation
Inside Shodoshima’s historic breweries, fermentation is not simply a manufacturing process.
The moromi develops with the seasons. The wooden barrels age. Microorganisms that have inhabited the brewery environment across generations continue to participate in every new batch.
Time becomes part of the ingredient.
What emerges is more than simply a seasoning.
It is a living expression of Japanese fermentation culture.
For Chefs Who Refuse to Compromise
For chefs and restaurants pursuing authenticity in Japanese cuisine, ingredients are never simply ingredients.
Their origin matters.
Their craftsmanship matters.
And the story behind them matters.
Around the world, a small but growing number of chefs and restaurants have discovered traditionally kioke-brewed soy sauce — choosing it not simply for its rarity, but for the complexity, depth and individual character that traditional fermentation can bring to their cuisine.
For those who continually seek authentic Japanese ingredients without compromise, we invite you to discover the soy sauces of Shodoshima.
These are not products created to imitate tradition.
They are products of the tradition itself.
More than four centuries of brewing culture, generations of microorganisms, wooden kioke, local knowledge and time are contained within every bottle.
Whether served with sashimi, used in a sauce, glaze, marinade or dashi, or incorporated into a chef’s own interpretation of Japanese cuisine, traditionally brewed soy sauce can contribute something beyond flavor alone.
It brings provenance.
It brings craftsmanship.
It brings a story to the plate.
For restaurants that believe every ingredient should have a reason for being there, this is soy sauce worth knowing.
Bring the story of Shodoshima to your cuisine.
From Shodoshima, Since 1913
YAMANI’s own story also began on Shodoshima.
Founded here in 1913, YAMANI originally supplied rice, foodstuffs and everyday necessities to the local community.
More than a century later, we return to those roots.
Our collection introduces carefully selected soy sauces from Shodoshima, with particular attention to traditionally brewed honjozo soy sauce and the increasingly rare culture of kioke fermentation.
We believe that an exceptional Japanese ingredient should be understood not only by how it tastes, but also by where it comes from, how it was made, and the people and traditions behind it.
These are not simply bottles of soy sauce.
They are part of a Japanese food culture that has survived generations — selected on Shodoshima and presented to those around the world who continue to seek the authentic foundations of Japanese cuisine.