Lao chou (dark soy sauce) translates as "old" soy sauce and is one of the two types of soy sauce used most often in Chinese cooking. The other is sheng chou (light soy sauce), or "raw" or "fresh" soy sauce. Aged for a longer period of time and with molasses or caramel and a bit of cornstarch added, lao chou is thicker and darker in color than sheng chou. It also is less salty and has more full-bodied flavor.
Lao chou is frequently added to marinades and sauces to add color and flavor to a dish; it is also found in Shanghai-style red-cooked dishes. Although this dark soy sauce is used primarily in cooking, as it needs heating to bring out its full flavor, you will also sometimes find it in dipping sauce recipes.
Health Benefits of Dark Soy Sauce
Singapore researchers believe dark soy sauce may contain significant health benefits. In a study conducted at the National University of Singapore, scientists found that dark soy sauce may contain up to 10 times the antioxidants found in red wine. Dark soy sauce also improves blood flow, meaning it could possibly help slow down the rate of certain degenerative diseases. (However, it’s good to keep in mind that dark soy sauce does have a high sodium content, although not as high as light soy sauce).
Also Known As: thick soy sauce (this is a bit tricky; some manufacturers label their soy sauces as thin and thick instead of light and dark. However, there is also a condiment called thick soy sauce that is basically dark soy sauce thickened and with added sugar).
Recipes Using Dark Soy Sauce
Red Cooked Dishes
Dark Soy Sauce Added to Sauce
Dark Soy Sauce in Marinades
Long LH, Kwee DC, Halliwell B. The antioxidant activities of seasonings used in Asian cooking. Powerful antioxidant activity of dark soy sauce revealed using the ABTS assay. Free Radic Res. 2000;32(2):181-6. doi:10.1080/10715760000300181