Soy sauce is a condiment made primarily with four ingredients: soybeans, wheat, salt, and water. There are many different kinds of soy sauces, but the three most common are light, dark and thick soy sauce. These are what most China and Taiwanese people use in the kitchen. Japanese soy sauce and tamari are similar but not identical products.
How Soy Sauce is Made
While it is possible to make quick, low-cost soy sauce using a chemical process, real soy sauce is cooked, aged, and processed over the course of months.
The soybeans, wheat, and water are cooked into a mash. They are then aged for a few days with Aspergillus, a type of fungus, to propagate koji mold. The resulting shoyu koji is mixed with brine and aged for several months. When it has been properly aged, the shoyu koji is pressed, resulting in raw soy sauce. Finally, the raw soy sauce is cooked to adjust color, flavor, and aroma.
Three Types of Soy Sauce and Their Uses
Light, dark, and thick soy sauces are all based on the same recipe. Extra processing produces different flavors and consistencies.
1. Light soy sauce (生抽):
When you see a Chinese recipe that asks for soy sauce, unless it very specifically states another type of soy sauce, it means “light soy sauce.” Light soy sauce tastes salty and it’s thin, light reddish brown in color and opaque. Light soy sauce is not the same thing as reduced-salt soy sauce or other products which may also carry labels such as "light" or "lite."
Chinese and Taiwanese people usually use light soy sauce for dips, marinating ingredients, dressings and stir-fry food. Light soy sauce is used for enhancing the flavor of any dish. But light soy sauce alone can be very strong and salty, but adding a little dark soy sauce can result in beautiful color and perfect seasoning.
2. Dark soy sauce(老抽):
Dark soy sauce is aged longer than light soy sauce and is often mixed with molasses or caramel and a bit of cornstarch. The resulting sauce is much darker than light soy sauce. The texture is thicker and it tastes less salty but sweeter than light soy sauce.
Chinese and Taiwanese people usually use dark soy sauce in stew types of dishes, like red-braised pork. The dark soy sauce gives the dish a nice caramel color and provides a little sweetness. Please don’t use too much dark soy sauce in dips, dressings or stews, though, as it can dye your ingredients a dark brown color.
3. Thick soy sauce(醬油膏):
Thick soy sauce is made with sugar, more wheat in the fermentation process, and sometimes, a starch thickener. It tastes sweet and is usually used in stir-fry foods and dips. Taiwanese people use it in stews and braised pork rice (滷肉飯). If you can’t find thick soy sauce in your local supermarket then you can use oyster sauce as a substitute.
Recipe for Thick Soy Sauce
Here is a simple thick soy sauce recipe:
300ml light soy sauce
1.5 teaspoon potato starch or corn flour
2 tablespoon brown sugar
- Add soy sauce into a small saucepan along with the brown sugar and half the amount of water. Bring it to the boil then turn down the gas power to it’s lowest setting.
- Mix potato starch or corn flour with the other half amount of the water and slowly stir it into the mixture on the stove. The soy sauce should be getting thicker and thicker during cooking as the potato starch or corn flour will enhance the density of the soy sauce.
- Once it has reached the right density, turn off the stove immediately and taste it to check the flavor. You can add a little bit of salt if you like it a bit stronger. After it has cooled down keep it in a clean and dry container or bottle and store it in the fridge.