Light and Dark Soy Sauce: Differences, Types and Tamari
Light Chinese soy sauce seasons and salts, while dark soy sauce mainly colors and tastes milder, thicker and slightly sweet. In Japanese cooking, the standard product koikuchi sits between the two, usukuchi is lighter in color but saltier, and tamari is brewed with little or no wheat.
To make brewed soy sauce, producers cook soybeans, mix them with roasted wheat or wheat flour and inoculate the mass with koji mold. Salt brine is then added, and the mash matures over months. At the end they press out the liquid and pasteurize it. Aging time, wheat share and additions such as sugar decide whether a light, dark or sweet sauce comes out.
Chinese soy sauce: light and dark
Light soy sauce (sheng chou, 生抽)
Light soy sauce is the workhorse of Chinese cooking. It is thin, reddish brown and distinctly salty. You use it for seasoning, marinades, dips, fried rice and stir-fries. When a Chinese recipe just says "soy sauce," it almost always means the light one.
Dark soy sauce (lao chou, 老抽)
Dark soy sauce ages longer and usually contains caramel color or molasses. It is almost black and thicker, and it tastes less salty but malty and slightly sweet. Its main job is color: a teaspoon gives braised dishes their glossy mahogany tone. It is typical in hong shao rou and in Taiwanese lu rou fan.
Important: with Chinese soy sauce, "light" does not mean mild. The light sauce is the saltier of the two.
Japanese soy sauce: koikuchi, usukuchi, tamari
Producers usually brew Japanese soy sauce (shoyu) from soybeans and wheat in similar parts. The wheat brings a rounder, slightly sweet aroma.
- Koikuchi is Japan's standard soy sauce. It is darker than Chinese light soy sauce and suits almost everything, from dipping to shoyu tare.
- Usukuchi comes from the Kansai region. It is lighter in color but saltier than koikuchi. Cooks use it when broths and vegetables should stay pale.
- Tamari contains little or no wheat and tastes denser and stronger. Many tamari products are gluten-free, but not all.
- Shiro is a very pale soy sauce with a high wheat share, mild and slightly sweet.
- Saishikomi is double-brewed, dark and intense, meant as a dip for sashimi.
The types compared
| Type | Color | Saltiness | Flavor | Typical use |
|---|---|---|---|---|
| Chinese light | reddish brown | high | salty, savory | seasoning, marinades, wok |
| Chinese dark | almost black | medium | malty, slightly sweet | color for braises and fried noodles |
| Koikuchi | dark brown | high | round, aromatic | all-purpose, dips, tare |
| Usukuchi | light brown | very high | clear, salty | light broths, vegetables |
| Tamari | dark | high | dense, strong | dips, low-gluten cooking |
| Kecap manis | black | low | syrupy sweet | Indonesian stir-fries |
On Indonesian kecap manis: it is thickened with palm sugar and is more a sweet sauce than a substitute for dark Chinese soy sauce. An example of dark, sweetish soy seasoning from Malaysia is daging masak hitam.
Which soy sauce for which dish?
- Look at where the recipe comes from. Chinese recipes distinguish light and dark, Japanese ones mean koikuchi when nothing else is stated, and Korean recipes usually mean jin-ganjang, a soy sauce similar to koikuchi.
- Separate seasoning from coloring. Many Chinese dishes use both types: the light one for salt, a dash of dark for color. Chao fan needs only light soy sauce, while in gan chao niu he dark soy sauce gives the noodles their typical brown color.
- For dips, use Japanese soy sauce. With sushi, tamago kake gohan or gyoza, koikuchi tastes rounder than Chinese light sauce.
- For Thai fried noodles, you need Thai types. Pad see ew lives on sweet, dark Thai soy sauce. Chinese dark soy sauce with a little sugar comes close.
Korean soy sauce
Korean cooking also has two main types. Jin-ganjang is the all-purpose soy sauce for marinades and braises like gamja jorim. Guk-ganjang literally means soup soy sauce. It is lighter and saltier and seasons clear soups and vegetable side dishes without coloring them much. If you cook Korean, you can replace jin-ganjang with Japanese koikuchi. For guk-ganjang, usukuchi fits better.
Common mistakes
- Using dark soy sauce as the salt source. The dish turns black before it has enough seasoning. Salt with light sauce and color with a little dark.
- Too much dark soy sauce. One teaspoon colors a whole pan. More makes the food bitter and dreary.
- Thinking usukuchi is mild. The light color is deceptive, and the sauce is saltier than koikuchi.
- Assuming tamari is automatically gluten-free. Some tamari contain wheat. Read the label.
- Cheap seasoning sauces instead of brewed soy sauce. Products with hydrolysate or flavorings taste flat. Look for "naturally brewed" and a short ingredient list.
Substitutes, allergens, buying and storage
If you are out of dark soy sauce, use light soy sauce with a pinch of brown sugar. The color will be paler, but the taste is roughly right. If you are out of the light one, use koikuchi in the same amount. Dark soy sauce does not replace the light one the other way around.
Soy sauce contains soy and, in most types, wheat, so gluten. If you avoid gluten, look for tamari or soy sauce explicitly labeled gluten-free.
Light soy sauce and koikuchi are available in every supermarket. Dark Chinese soy sauce, usukuchi and tamari are sold at Asian grocery stores and online, some also at health food stores. Once opened, soy sauce keeps for a long time. In the fridge the aroma stays fresh longer and the sauce darkens more slowly. Small bottles make sense if you rarely need a type.