The most common soy sauce ingredients include soybeans, wheat, or other fermenting grains and Aspergillus molds along with salt and water. Soybeans are the base for the condiment, having a soft texture conducive to fermenting. The wheat's carbohydrates convert to acid and alcohol during this process, caused by the introduction of Aspergillus molds containing two types of bacteria. Salt and water are also extremely common.
Fermented soybeans are the main ingredient in this mainstay condiment. A soybean is a legume native to China that's been present for over 13,000 years. A leather pea-shaped pod envelopes one or more beans with a smooth skin and soft texture. The beans are green, yellow, or brown, as well as black. In addition to being one of several soy sauce ingredients, soybeans are widely used in food production in various capacities.
Soybeans are fermented in salt water with the Aspergillus oryzae or Aspergillus sojae molds. The mixture sits for a certain amount of time. This creates a soybean paste which is pressed to extract the soy sauce.
Wheat and other grains are commonly used as soy sauce ingredients. Through the introduction of the molds, the wheat's carbohydrates are converted into alcohol, acid, and carbon dioxide, and the chemicals give soy sauce its strong signature taste. Roasted wheat is mixed with pre-boiled beans, the introduced to the chosen mold. This mixture, called koji, mixes together for several days, the mold fermenting it. Once the sauce is pressed, the solid mixture of soy and grain is processed for animal feed.
The most common soy sauce ingredients include the Aspergillus genus of molds used for fermentation. A variety of yeasts may occasionally be substituted. The mold contains the bacillus bacteria that adds its noticeable scent and ammonia, and Lactobacillus lowers the koji's pH level by creating lactic acid. These molds aren't needed if the condiment contains hydrolyzed soy protein, an additive that allows for longer shelf life. This ingredient is common in fast-food packs of soy sauce.
Salt and water serve as the other most common soy sauce ingredients. Fermented soy sauce has an unmistakably salty taste, and it also acts as a preservative, inhibiting growth of other bacteria. Water allows the ingredients to liquefy and gives the sauce its thin viscosity.