Uchu Brewing

How Soy Sauce is Made in Japan | Eater

"Led by brewer Masatsugu Fueki, this shoyu brewery preserves a more-than-220-year-old natural method of soy sauce production, following ancestral rules day to day. The finished product uses only three ingredients—soybeans, wheat, and salt—but relies on complex microbial activity: protein-rich Oosuzu soybeans from Aomori are steamed and blended with crushed, sugar-rich wheat, then inoculated with Koji mold to break down the sugars. The mash is combined with salt water in enormous wooden barrel tanks (there are 38 on-site, the oldest about 150 years old) — part of a disappearing craft that has fewer than 50 handmade wooden tanks left in Japan, and which the brewer is attempting to recreate. The mixture is hand-stirred with a giant dowel to aerate the microorganisms, aged for two to three years, then pressed with 300 tons of pressure every 30 seconds to extract the raw liquid; that liquid is blended, heated, and left to ferment for a week before bottling. The result is described as a rare, thoroughly balanced flavor that lingers on the tongue, an outcome the brewer calls a joy and attributes to faithfully maintained tradition." - Terri Ciccone