Naturally brewed soy sauce is made using only four basic ingredients: soybeans, wheat, salt and water. Careful selection is required for these simple ingredients, as they directly influence the flavour and aroma of the soy sauce.
The Role of Soybeans in the Fermentation Process
The unique characteristics of soy sauce originate primarily from the proteins contained in soybeans. The soybeans are first soaked in water for an extended period, and then steamed at high temperatures.
The Role of Wheat in the Fermentation Process
The carbohydrates contained in wheat are the components that give soy sauce its fine aroma, and the wheat also adds sweetness to the soy sauce. The wheat is roasted at high temperatures, and then crushed to facilitate fermentation.
The Role of Salt and Water in the Fermentation Process
The salt is dissolved in water. This salt-and-water solution controls the propagation of bacteria during the brewing process and acts as a preservative.