What Is Shoyu?
Soy sauce, a thin, umber liquid that’s popular to use with stir-fries, dipping sauces, and sushi, originated in China centuries ago. There, the condiment was usually 100 percent soy, with no other ingredients. The fermentation process introduces the rich flavor and intense salinity that’s associated with the sauce.
When soy sauce was introduced in Japan, however, the recipe changed to equal parts soybeans and wheat. Brewing the beans with wheat adds a subtly sweet flavor that’s less harsh and more rounded. This Japanese-style soy sauce is called shoyu.
Shoyu has carved out a cadre of intensely loyal fans, people who prefer the full-bodied flavor and delicate sweetness over assertive Chinese soy sauce. Not all shoyus are made the same, however, so it’s smart to learn about the variety you want before you head to the store.
Types of Shoyu
Shoyu can be divided into five main categories:
Koikuchi: Known as “dark” shoyu, this popular variety is rich and intense. Shoyu bottles in most U.S. grocery stores are the koikuchi variety, even if it isn’t labeled as such. It can be used in marinades, basting sauces, dips, stir-fries,and more.
Usukuchi: This “light” shoyu is thinner, with a more salty, assertive flavor. However, at the end of the fermentation process, mirin (a sweet rice wine) is added, so usukuchi shoyu is sweeter than koikuchi, though not the sweetest shoyu option.
Tamari: Tamari uses little to no wheat, so it’s a great condiment option for people who are eating gluten-free. Tamari tends to be thicker and richer, almost sweet. It’s ideal for dipping, and it’s frequently used in stir-fries, salads, and drizzled over light proteins like fish and chicken.
Sai Shikomi: You’re unlikely to find this type of shoyu at mainstream grocery stores, but it may be in your local Asian market. This sweet sauce is double fermented, so it takes longer to produce than other varieties.
Shiro: This lighter shoyu variety is a great way to add shoyu flavor but not turn your ingredients or final dish a dark hue. With a higher percentage of wheat, this type of shoyu is also sweeter than the others. It’s particularly great in hot pots, steaming soups, and tossed with steamed vegetables.
What is Nama Shoyu?
In Japanese, “nama” means raw, so nama shoyu is a raw or unpasteurized shoyu sauce. Because it is cultured or fermented, nama shoyu often contains beneficial living enzymes and organisms, like probiotics. Other shoyu are heated for preservation purposes.
Some tasters claim nama shoyu is more delicate and less assertive, but it still maintains the classic shoyu balance of sweet and salty. It’s also a favorite among “raw” food eaters, but it does contain gluten—almost all shoyu does—so raw purists may not be able to eat it.