My mother always kept a gallon of Kikkoman Soy Sauce in a kitchen cubby. She grabbed the large container whenever she needed soy sauce for marinades, fried rice or dipping sauces. Later, as I began cooking Korean dishes for myself, I'd buy the same soy sauce brand. I didn't think too much about different types of soy sauce until I started buying other brands.
Most recipes don't specify the type of soy sauce to use, but they can vary wildly in flavor, texture, and appearance. Here's a primer on what's out there, along with the best uses for each.
First, a Definition..
One of the oldest condiments in the world (it's got a three-millennia history!), soy sauce is a by-product of fermented soybeans and wheat that have been mixed with brine. First, Aspergillus molds are added to cooked soybeans and roasted wheat resulting in a mixture called koji (the term koji can also be used to refer to just the bacterial culture as well). After the molds grow over three days, the culture is combined with salt water and transferred to large vats where lactobacillus—a bacteria that breaks down sugars into lactic acid—is added.
The resulting mixture, the moromi is allowed to ferment for a time period ranging from six months for standard supermarket brands to several years for high-end bottles. The soy sauce is finally strained, pasteurized, bottled, and sold.
Japanese Soy Sauces, or Shoyu
Stand in the international foods aisle of a mainstream grocery store and you're most likely to see Japanese-style soy sauces, known as shoyu. Traditional Chinese soy sauces were made with 100% soy (some modern Chinese soy sauces contain wheat too). When the brewing method made its way to Japan, the recipe was modified to use an even ratio of soybeans and wheat, resulting in a sweeter, less harsh flavor. Japanese-style soy sauces tend to be clearer and thinner than Chinese sauces.
Koikuchi (dark): Japanese soy sauces are split into dark (koikuchi) and light (usukuchi) with the former being more commonly used. Most major supermarket brands available in the U.S., like Kikkoman's All-Purpose Naturally Brewed Soy Sauce don't indicate a type on the label, but are considered a "dark" soy sauce, according to Shizuo Tsuji, author of Japanese Cooking: A Simple Art.
"A good all-purpose choice"
Kikkoman's All-Purpose is produced in the company's factory in Walworth, Wisconsin. "Less Sodium" soy sauce is made the same way as regular soy sauce, but about 40 percent of the salt is taken out post-brewing. Dark Japanese soy sauces have a deeper color, but actually taste less light. A good all-purpose choice, they are best used in marinades and basting sauces, but are perfectly acceptable for dipping or stir-fries as well.
Usukuchi (light): These are lighter and thinner than their darker, richer counterparts, but have a more assertive, salty flavor and a slight sweetness from the addition of mirin, a sweet rice wine. Primarily used in the Southern Kansai region of Japan, light soy sauces are used to season ingredients without turning the ingredients into a darker color. They can be used in place of dark soy sauce, but they should be used more sparingly because of their intense flavor.
Tamari: More similar to traditional Chinese soy sauce, this is made with soybeans and little to no wheat. Tamari started in the fifteenth century as a by-product miso (fermented soybean paste) production, and was completely devoid of wheat. These days, many tamari-style soy sauces actually contain a trace of wheat, though most major brands like San-J, Wan Ja Shan, Eden Organic and Ohsawa offer gluten-free versions.
With a higher soybean content, tamari has a stronger flavor and is ideally used as a dipping sauce. If you have a wheat allergy, tamari can be a good alternative to shoyu, though you should always be sure to check the ingredients list for the presence of wheat.
Other Japanese Soy Sauces: While tamari is made with more soybeans, shiro, or white soy sauce, is brewed with more wheat. It has a lighter color and flavor. It's typically used as a dipping sauce for sashimi made with mild, white-fleshed fish where a darker sauce would overpower and discolor the delicate slices. Saishikomi, or "twice-brewed" soy sauce, has a stronger flavor than tamari.
To produce it, the saltwater brine in the fermentation stage of standard shoyu is replaced with a previous batch of already-brewed soy sauce. Shiro and saishikomi are not as commonly found in stores compared to other soy sauces. Check out Japanese specialty markets to find them.
Chinese Soy Sauces
"If a Chinese recipe calls for "soy sauce" without any further detail, you can assume it means light soy sauce."
Light: Made from the first pressing of fermented soy beans, these are generally more expensive than dark soys. Also known as "fresh" soy sauce, you'll sometimes find it labeled "pure bean" or "thin." These soy sauces are meant to enhance flavors when cooking. It's by far the most common cooking sauce in Chinese cuisine. If a Chinese recipe calls for "soy sauce" without any further detail, you can assume it means light soy sauce. Double-fermented light sauces, which have a mellower, more complex flavor are also available and used primarily for dipping.
Dark and Double Dark: Like Japanese dark soys, Chinese "dark" soys are darker in color and thicker in texture, but tend to be lighter in saltiness. They are generally fermented for a longer period of time than their thin counterparts and often have added sugar or molasses, giving them a sweet-salty flavor and viscous texture. They are used solely for cooking, often added at the last stages to season and add color to sauces.
Chemical Soy Sauce
Chemical soy sauces: These are made over the course of about two days by hydrolyzing soy protein and combining it with other flavorings. Their flavor is far removed from traditional soy sauces made with fermented soybeans. Harold McGee explains the process in On Food and Cooking by saying:
Nowadays, defatted soy meal, the residue of soybean oil production, is broken down—hydrolyzed—into amino acids and sugars with concentrated hydrochloric acid. This caustic mixture is then neutralized with alkaline sodium carbonate, and flavored and colored with corn syrup, caramel, water, and salt.
We strongly recommend avoiding these types of sauces. Check the list of ingredients on a bottle before you inadvertently buy an artificial sauce.
Other Popular Soy Sauces
While many Asian countries have their own soy sauce styles and variants, another relatively commonly found style in the U.S. is Indonesian Kecap manis. It's a sweet soy sauce native to Indonesia made with fermented soy beans and flavored with palm sugar, star anise, galangal and other aromatics. It's widely used in many Indonesian dishes and is the primary flavoring in bami goreng, a popular stir-fried noodle dish. Kecap manis derives its name from the same Malay fish sauce (kicap) that our tomato-based ketchup is distantly related to.
People tend to be slapdash in their soy sauce storage, but it's a relatively fragile sauce that can easily develop fishy, off-flavors if not stored properly.
"Soy sauce's two main enemies are light and heat"
Soy sauce's two main enemies are light and heat, so be sure to store it in a dark place away from a heat source (for example, above the stove or on the countertop). Once a bottle of soy sauce is opened, keep it in the fridge if you don't expect to use all of the soy sauce within a month or so—particularly if its in a clear glass bottle. To save money, you can purchase large metal cans of soy sauce and store them in a dark cupboard, refilling a smaller glass container in your refrigerator as needed.
Recipes With Soy Sauce
Use soy sauce for rich marinades, stir-fries and dipping agents.
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