Soy sauce is a brown, salty liquid that is made from soybeans, salt, water, wheat, and mold. The process for making soy sauce is fairly simple: Boiled soybeans and roasted wheat are placed into a barrel with salt, water, and mold. The mixture is allowed for ferment for one to two years. Finally, the liquid is drained off the fermented material, strained, and pasteurized.
Soy sauce was brought to Japan from China during the ninth century. By the 1600s, distinctly “Japanese” soy sauce had emerged. Japanese soy sauce is made with more wheat than the Chinese variety. This makes it lighter, sweeter, and clearer than Chinese soy sauce.