Soy sauce is a brown, salty, liquid used as a condiment or seasoning in many Asian cuisines. Soy sauce is made from fermented soybeans, salt, water and sometimes roasted grains. Soy sauce has an earthy, umami flavor, which makes it an ideal all-purpose seasoning.
How is Soy Sauce Made?
The traditional method for brewing soy sauce requires multiple steps and can take a days to months to complete, depending on the recipe. To make soy sauce, soybeans are first cooked to soften the bean. Next, bacterial and fungal cultures are added to begin the fermentation process. Roasted wheat or other grains may also be added to this mixture to provide a unique flavor.
The soybean culture mixture is combined with a salt brine and allowed to “brew” for a specific amount of time. During this process, the microorganisms break down proteins and sugars that are naturally found in the soybeans into numerous compounds that create the complex flavor and color of soy sauce.
After the fermentation process, the mixture is pressed to extract the dark brown, flavorful liquid. The resulting solids are often used as animal feed. Before the extracted liquid is packaged and sold as soy sauce, it is pasteurized to eliminate any harmful microorganisms and filtered to reduce particles and other debris.
Advancements in food production have led to a faster, less expensive method of producing soy sauce, which uses acid-hydrolyzed vegetable protein. This method only requires a few days and produces a more consistent product with a longer shelf life. Opponents reject this method, as it does not create the depth of flavor found with the traditional brewing method.
Soy Sauce Varieties
There are literally hundreds of soy sauce varieties. Varieties depend on the ingredients used, the method used to create the sauce, and the region in which it is made. In the United States, there are a few main varieties that may be encountered in grocery stores or recipes: light, dark, low sodium, and tamari.
Light Soy Sauce – This thin, brown liquid is what most Americans refer to as regular soy sauce. It is a good all-purpose seasoning and condiment.
Dark Soy Sauce – This type of soy sauce has had molasses or caramel added after the brewing process, which thickens the sauce slightly and produces a sweeter, more complex flavor.
Low Sodium Soy Sauce – Salt is an important component in the production of soy sauce because it acts as an antimicrobial agent. Most low sodium soy sauces are made using the acid-hydrolyzed vegetable protein method, which does not utilize bacterial and fungal cultures and therefore requires less salt.
Tamari – This Japanese soy sauce is made with only soybeans and no wheat or other grains. Tamari has a very clean flavor and is favored by those who require a wheat or gluten free diet.
Soy Sauce Nutrition
Soy sauce is notorious for containing high amounts of sodium, but it is also rich in antioxidants, isoflavones, protein, and even a small amount of fiber. One tablespoon of soy sauce contains roughly 11 calories, 2 grams of protein, 1 gram of carbohydrates, and 1006 mg of sodium. The nutritional content will vary depending on the variety of soy sauce and the ingredients used to make it.
How to Store Soy Sauce
Unopened soy sauce is shelf stable and can be kept in a cool, dark place. Once opened, soy sauce should be kept in the refrigerator for optimum flavor. The high salt content of most soy sauces will prevent dangerous microorganisms from proliferating at room temperature, but the delicate flavor compounds produced during the fermentation process are best protected under refrigerated conditions. Low quality soy sauces are less likely to have a noticeable degradation in flavor if stored at room temperature.