Let’s consider one of the most popular flavorings for over 2000 years world-over. Soy Sauce is often compared to selecting a fine wine. It was originally a way to stretch salt – an expensive commodity. The traditional fermentation process using soybeans may take up to six months or more compared to two weeks by hydrolysis in a bio-reactor. National Geographic has done an informative video on how soy sauce has been made in Japan for over 750 years. After brewing, some sauces can be blended with mushrooms or thickened with starch, sugar or molasses. Sweeter sauces are commonly used for dipping. Soy Sauce manufacturers often modify recipes to regional tastes. There is a long history of soy sauce manufacturers in Vietnam, Thailand, Taiwan, Malaysia, Singapore, Korea, Japan, Indonesia, Hawaii, China, Burma, and the Philippines,
You may use Yamasa, or been in a restaurant with Kikkoman soy sauce on the table with a red or green lid. Red meaning traditional and green meaning sodium reduced soy sauce with ingredients including water, wheat, soybeans, salt and a preservative called sodium benzoate. If your interest was to brew your own traditional sauce Cooks Illustrated has a detailed process you could follow. The commercial process of fermentation or faster hydrolysis in a bio-reactor is commonly used to make the sauce.
Numerous companies make a gluten-free soy sauce. Japanese tamari soy sauce is traditionally wheat-free and gluten-free like Kikkoman’s Gluten-Free Tamari Soy Sauce traditionally brewed from water, soybeans, salt and sugar.
A good read is Ronald E. Yates book about the history of Shige Maki and the Kikkoman company and how they changed history.