The highest quality recognition:

We produce the very best soy sauce in our state-of-the-art plant, but brewing processes remains the same as in 1645. YAMASA soy sauce has been preferred among the majority of high-end Japanese restaurants, sushi, and kabayaki-eel restaurants.

YAMASA Difference

Soy sauce manufacturers use different kinds of Koji mold, and we use a unique strain of mold called YAMASA Aspergillus that we have nurtured over hundreds of years, since the Edo era. It produces a particular color, flavor, and aroma, and ultimately, a unique taste that cannot be imitated. YAMASA Aspergillus is the lifeblood of YAMASA’s delicious soy sauce.

Koji mold is a kind of mold, rich in enzymes, that changes soybeans and wheat into tasty soy sauce. It is also used to make Japanese traditional fermented products such as sake (rice wine), sweet sake (Mirin), and soybean paste.

YAMASA’s History

Gihei Hamaguchi, the founder of the YAMASA Corporation decided to start producing soy sauce in the Choshi, Chiba prefecture.

Choshi is where the warm Kuroshio Current meets the cold Oyashio Current, creating a humid climate with cool summers and warm winters. This made it the perfect location to produce great tasting soy sauce.

YAMASA soy sauce production rapidly increased due to remarkable development of food culture in Edo. Since the Edo era, we have produced the very best soy sauce, as shown in our logo and certified by the government.

We have strived to produce genuine soy sauce and to maintain authentic skills since we first started soy sauce brewing.

The brilliant reds and delicious flavors of YAMASA soy sauce are the result of all this tradition and history.

YAMASA’s Quality

Translucent and Brilliant Red:

Adding a hint of the YAMASA’s brilliant red color often completes a dish. The clear and translucent YAMASA red would add richness to the original color of the food and its vividness stands out when compared to dishes using others.

Rich Aroma:

Another aspect of the YAMASA’s quality that makes our brand stands out is the rich aroma that is mouthwatering and mellow. It creates the rare, delicate fragrances that are attractive to many who love YAMASA.


One of the key components of soy sauce taste is “UMAMI,” one of the five flavors invented by the Japanese. It makes foods delicious and flavorful. But it is important in cooking that UMAMI should not stand out by itself. YAMASA’s soy sauce enhances the original flavor of the food and creates a perfect balance and will not interfere with it. We believe this is YAMASA’s taste and its quality.