Soy Sauce

Abstract

The term soy sauce commonly refers to a light- to dark-colored liquid made from soybeans. Soy sauce is a condiment and seasoning which has a savory taste and specific aroma, and it contributes to palatable cuisines in many Asian countries. There are three different categories of soy sauce on the market, according to the production process, i.e., fermented soy sauce, chemical soy sauce, and a combination of fermented and chemical soy sauce (Fukushima, 1981; Hesseltine & Wang, 1980). However, the original soy sauces are usually the fermented ones (Fukushima, 1981). They started to use chemical soy sauce decades ago; it was made by a rapid acid hydrolysis of soybean proteins. Fermented soy sauce has been produced since ancient times by using microbes to ferment soybeans for months. Traditionally, the fermentation process involves molds at the first stage and then bacteria and yeasts at the next stage under high salt condition.