“Don't dunk your nigiri in the soy sauce. Don't mix your wasabi in the soy sauce. If the rice is good, complement your sushi chef on the rice.” ~ Anthony Bourdain
Overview
I set out to learn as much as I could about fermentation and how food has been aged throughout history, which is my mission to glean aspects of food production and the process of fermentation to make things taste delicious. In Japan, Shoyu (Soy Sauce) brewing originated in Yuasa Town, Wakayama. The Soy Info Center produced a 2,523 page history of Soy Sauce production dating back to 160 CE (Common Era), when Shoyu (Soy Sauce) was brewed in 150-year-old cedar barrels called Kioke, and still are today. By 1647 Japanese soy sauce was exported from Nagasaki, Japan, by the Dutch East India Company. In 1893 soy exports expanded to the U.S. commercially into San Jose, CA. Today, Kikkoman brews a mass produced steel barrel aged fermented product in Folsom, California.
Kioke Barrel - Cultural Cooperage
Kioke barrels are made of hand-carved cedar staves, traditional cooperage - braided barrel rings - lasting up to 150 years if cared for properly. Each year, the cooperage and Shoyu brewers in Japan hold a ‘Cultural Summit’ in Kagada Shodoshima, Japan. People from all ends of the food spectrum came to support and learn how to build Kioke, an effort to rebuild the Kioke cooperage. Carpenters showed from Fukushima and other cities to learn the practice. Everyone knows the traditional soy sauce brewing market is dependant on cedarwood barrel building to uphold tradition, and the industry is built around the culture of barrel fermented soy sauce. The first step in preserving a centuries long tradition is knowledge sharing, which in turn could grow the brewing by 1% to 2% market share.
Shoyu Production - Koji To Moromi
Throughout history, Shoyu has been recognized as the genesis of Worcestershire sauce, Catsup, and hot pepper sauce production around the globe. 1% of Japan's Shoyu supply is made through a barrel aging process, and fermented in Kioke for 2-10 years or more. Some shoyu takes up to 20 years to ferment, age, press, cook, and bottle.
In order to get to press and bottling, soy sauce has to reach a maturity called Koji. A point at which soybeans are steamed, wheat is roasted and crushed, fungus is added to create mold. Koji, the byprdocut is placed on wooden trays and naturally heated to fermentation for 2-3 days. The next brine and fermentation stage, a brewmaster adds the salt and water to make Moromi, from the Koji. Moromi is typically used a by product to produce Miso, and make soups and stir fry. Bacteria are used to spawn fermentation in the soy-wheat mash. The product is aerated in the Kioke, daily during each stage smelling like effervescent fruits like apples, and bananas. The Moromi ferments for a minimum of 18 months, to upwards of 5-10 years in some cases.
Pressing The Moromi & Bottling
Once the Moromi meets a minimum of 18 months aging in the Kioke, the brewmaster removes the Moromi from the tank and sends it through the pressing process, which usually takes up 3-5 days. The Moromi is layered into a porous cloth, wrapped three times, folded onto itself and layered over 100 times to create a level for the press. The raw soy sauce is extracted from the Moromi mixture, and sent to a barrel for boiling, cooling, and then bottling.
Three U.S. Based Craft Shoyu Brewers
Moromi - A Connecticut based Shoyu brewery - listed under Mystic Koji, LLC.
CinSoy Foods - Running a small craft soy sauce brewing operation in Cincinnati, Ohio.
Bourbon Barrel Foods - Based out of Louisville, Kentucky producing a small batch soy sauce, fermented in Kentucky bourbon barrels.