In Japan, soy sauce (called shouyu (醤油) in Japanese) is one of the main ingredients in many recipes. That doesn’t mean that you’re stuck with one flavor, however, as there is a huge variety of different types of soy sauce.
Soy sauce first started being used in China around 500 BCE, when Buddhism was becoming widely practiced. Because most Buddhist monks were vegetarians, they needed a seasoning not made from the meat and salt of previously used seasonings. It wasn’t until 500 CE, however, that soy sauce made its way to Japan in the way that most foods did: through a Japanese Buddhist priest studying in China. Once soy sauce entered Japan, the brewing method changed; one of the changes was the addition of an equal measure of wheat to soybeans, which allowed for a less overwhelming flavor.
Soy sauce is made over a period of time ranging from a few days to months. First, soybeans are cooked and fermenting agents are added to them. Depending on the type of soy sauce being made, roasted wheat or other grains are added to the soybean mix. After this, the mixture is added to a salt brine and allowed to set for however long the specific type of soy sauce requires. The mixture is then pasteurized in order to eliminate harmful microorganisms then strained and filtered to separate the liquid and solid products; the liquid becomes soy sauce and the remaining solids can be used as animal feed.
As mentioned earlier, there are many types of soy sauce; in fact, the Japanese Soy Sauce Information Center (しょうゆ情報センター) list five main types of soy sauce. The first two types, Koikuchi (濃口) and Usukuchi (淡口) are each named after the color of the liquid. Koikuchi is the dark version and is the soy sauce that you might find at any store in the “Asian food” section, as it makes up around 80% of soy sauce consumption. It has the deep flavor typically associated with soy sauce along with a very mild sweetness. On the other hand, Usukuchi is “light soy sauce.” It’s named after its light color instead of a light flavor, as it actually contains around 10% more sodium than Koikuchi will, resulting in a saltier flavor.
The third type of soy sauce is called Tamari (溜まり), which was actually the word used to refer to all soy sauce until some time in the 1400s, when the word shouyu became popularized. Tamari has a thicker consistency than other soy sauces and is infused with a deep umami flavor. Traditionally, tamari is made without any wheat, so most tamari on the market is made without wheat; in fact, wheat-free soy sauce is often called tamari-style soy sauce, making tamari safe for a gluten-free diet. Tamari is often referred to as “sashimi tamari,” as it’s a popular soy sauce to accompany sashimi and sushi. When heated, tamari becomes red in color, making it a good addition to sauces and senbei (煎餅), or rice crackers.
The fourth type of soy sauce is Saishikomi (再しこみ), a specialty soy sauce made in the Yamaguchi prefecture. The “sai” (再) in the name means repeat, as the fermenting agent called koji (fermented rice) is added twice, once in the main brewing process and then later again after the soy sauce has been fermented. The final type of soy sauce on the list is Shiro (白), or white. Shiro soy sauce is both the lightest in flavor and the lightest in color of all of these varieties. It’s the sweetest of the soy sauce varieties and used mainly in dishes that need to retain their color or flavor profile.
There are also newer varieties of soy sauce, not yet added to the Soy Sauce Information Center’s list, that have gone into production as well. Two such soy sauces, gen’en (減塩) and usujio (薄塩) are made with health-conscious soy users in mind. Both gen’en and usujio varieties are reduced sodium; gen’en is made with 50% less salt and usujio is made with 20% less salt.
Soy sauce was conceived as a meatless seasoning agent, but it can be used in a variety of ways. Most people are familiar with using soy sauce as a dipping sauce for sushi and sashimi or even meats. However, soy sauce can also be used as a base in soup broths. If you’re a ramen fan, you’ve probably had shouyu ramen. Shoyu is also the base for sauces such as teriyaki sauce and gyoza dipping sauce. Shoyu can also be used straight to season foods like stir-fry and fried rice. If you’d like to try adding soy sauce to everyday recipes, it can also be used in pretty much any recipe in place of salt in anything from burgers to soups.
The two most popular brands of soy sauce are Kikkoman and Yamasa; both brands produce soy sauce in Japan and in the USA. Kikkoman and Yamasa are both tried and true brands having been around since the 1600s in Japan and the 1800s in America. At Asahi we sell all of the types of shoyu mentioned here, including Kikkoman and Yamasa brands, if you want to add soy sauce variety to your life. Remember, you’re not limited to using soy sauce as a condiment; use it as a marinade or a sauce or soup base, there’s almost no limit to the ways you can add soy sauce to your daily life.