Soy sauce is a traditional Japanese condiment, full of umami and flavor. Consisting of soybeans, wheat, roasted grains, and sea salt, it’s an indispensable part of Japanese cuisine.
If you are familiar with Japanese or Asian cuisines, you probably recognize the dark brown, salty liquid used in many dishes. Soy Sauce (shoyu 醤油 in Japanese) is an all-purpose ingredient in Japanese cooking and many other East Asian and Southeast Asian cuisines.
These days, soy sauce is almost as mainstream as ketchup, used in many non-Asian cuisines for its umami properties.
Table of Contents
What Is Soy Sauce
Soy sauce is one of the foundational elements of Japanese cuisine. It imparts flavor and color to the dish without overpowering it and is a vital part of stir-fries, nimono, noodle soups, glazes, and more.
Originated in China over 2,000 years ago, it is one of the oldest condiments on the planet. Japanese soy sauce differs from other Asian varieties in that it has a sweeter profile and uses equal parts soybeans and wheat.
How It’s Made
Soy sauce consists of soybeans, wheat, salt, and sometimes roasted grains. There are two groups of Japanese soy sauce depending on its production: traditionally and chemically produced.
Traditionally production
The traditional brewing method involves soaking and steaming soybeans for several hours. Then it’s mixed with roasted and ground wheat flour and culturing mold (Aspergillus oryzae, also used to make miso) to make shoyu koji. This mixture then ferments for three days.
The shoyu koji mixture is then combined with a salt brine called moromi and allowed to brew and ferment for several months. Then it is filtered, pasteurized, and finally bottled.
High-quality soy sauce uses natural fermentation and is labeled “naturally brewed.”
Learn more about its production method at Kikkoman’s website.
Chemical production
Chemical production is a cheaper and faster method of making it, where a chemical acid is added to break down the proteins in the soybeans and wheat. This method produces soy sauce in a few days instead of months. The finished product is usually flat and less aromatic in taste and flavor. Therefore, you’ll find additives and salt in the final product to boost color and flavor. If you see “hydrolyzed soy protein” or “hydrolyzed vegetable protein” on the label, it’s chemically produced.
What Does It Taste Like
The primary taste is salty, but it also has a naturally sweet, slightly earthy, sour, and savory profile. It’s different from salt as it undergoes fermentation, resulting in a highly complex and nuanced flavor. A good quality soy sauce should be aromatic and balanced in taste.
You’ll notice the aroma of good soy sauce when heated. When adding it to a pan, try pouring it into the sides of the pan, so it cooks a little before seasoning the pan contents.
Uses
The Japanese use the condiment in the following contexts:
- to flavor and enhance a dish
- to season ingredients
- to enhance the color of a dish
- to make sauces and dressing when combined with other ingredients
Its role is like salt, where you can add it while cooking or consuming with food. It lends fragrance and savory characteristics to the dishes. Without it, Japanese food wouldn’t be what it is.
How is Japanese Soy Sauce Different from Others?
Japanese soy sauce is made with equal parts of soybeans and wheat, whereas the Chinese version has a higher ratio of soybeans to wheat.
To cook Japanese food with integrity, it’s important to use Japanese soy sauce. Soy sauces from other countries are made for their respective cuisines. The taste and uses can differ significantly, which will alter your cooking.
If you wish to achieve the best flavors and consistency in Japanese dishes, use Japanese soy sauce.
According to the Japan Agricultural Standards (JAS), there are five varieties:
- Koikuchi shoyu (濃口醤油, dark-colored soy sauce)
- Usukuchi shoyu (淡口醤油, light-colored soy sauce)
- Tamari shoyu (たまり醤油)
- Saishikomi shoyu (再仕込み醤油)
- Shiro shoyu (白醤油)
1. Koikuchi Shoyu (Dark Colored Soy Sauce) 濃口醤油
Koikuchi is the standard Japanese soy sauce. It’s typically made from wheat and soybean. The mighty all-purpose choice, it’s excellent for cooking and as a seasoning sauce. Most koikuchi aren’t labeled as such, but they are koikuchi. Known for its well-rounded character, it has a balance of umami, sweetness, sourness, and bitterness. The salt content is about 16%.
If you can, find marudaizu (丸大豆, “whole soybeans”), made with whole soybeans rather than a soybean mash, which has a rounder and nuanced flavor. It’s slightly more expensive and of higher quality than the regular kind. Use in raw applications than in cooking, where you’ll notice the difference.
The bottle above is my favorite organic brand by Kikkoman (imported from Japan). You may find it at Japanese grocery stores, H-Mart, and some Asian grocery stores. You can also buy it online on Amazon.
2. Usukuchi Shoyu (Light Colored Soy Sauce) 淡口醤油
Usukuchi, or light-colored soy sauce, is higher in sodium than the regular and has less umami. The reason is that the additional salt suppresses the fermentation process. Primarily used in southern Kansai cuisine, it is used for cooking dishes such as Takikomi Gohan and braises. The light color won’t darken the final dish like regular soy sauce.
The salt content is 18-19%.
Use usukuchi for udon noodle soup, chawanmushi, and simmered dishes (nimono).
3. Tamari Shoyu たまり醤油
Tamari is a by-product of miso, the leftover liquid from pressing miso. It is popular in the Chubu (Nagoya) region, mainly Aichi prefecture. Characterized by its thick syrupy texture, rich umami taste, and fragrance, tamari is dynamic. It’s wonderful on sushi and sashimi, glazed dishes like teriyaki, or as a finishing seasoning. The salt content is around 16%.
The ingredients are just soybeans and contain little to no wheat. Some are gluten-free but do check the label first. The texture and flavor differ from regular soy sauce, and so it’s not the best gluten-free replacement.
4. Saishikomi Shoyu 再仕込み醤油
Sashikomi shoyu is a “double-fermented” soy sauce. It is thicker in color and texture than regular soy sauce. With a high price tag, it’s usually reserved as a dipping sauce for sashimi and sushi. It’s not for cooking. The salt content is 16%.
5. Shiro Shoyu 白醤油
Shiro Shoyu is the opposite of tamari and is made with minimal soybeans and more wheat. Literally “white soy sauce,” it gets its name due to its clear color. It has less umami and richness compared to dark soy sauce. It’s used to preserve the ingredient’s natural color such as clear soups and eating light-colored raw fish. It’s high in sugar and salt.
6. Amakuchi Shoyu (Sweet Soy Sauce) 甘口醤油
Amakuchi sweet soy sauce is the mainstream choice in southern Japan, where it’s used like regular soy sauce. If using this in cooking, make sure to reduce the amount of sugar.
7. Gluten-Free Soy Sauce
Kikkoman USA as well as other companies have gluten-free options.
For gluten-free recipes, click here.
Read more about Tamari Soy Sauce
How to Choose the Best
Good quality soy sauce will contain the following: soybeans, wheat or barley, salt, and water. Look for the label with ‘naturally brewed.’ Avoid those containing preservatives, corn syrup, and additives.
I use Kikkoman for cooking. It is a well-established brand in Japan and is affordable and widely accessible everywhere. There are also other premium brands such as Yamasa, Kamebishi, and Kishibori that are slightly more expensive. Pricer brands are due to small-batch production using a longer fermentation process.
We tried the American-made Bluegrass Soy Sauce. It’s fermented in bourbon barrels, imparting a complex flavor and aroma. It’s excellent for dipping sauces or salad dressings.
Substitution
There is no substitution as it’s a unique fermented product that defines Japanese cuisine. I highly recommend using Japanese soy sauce from other Asian soy sauces such as Chinese or Korean because each is made for its respective cuisine.
However, for those who are allergic to soy, you can use the same amount of coconut aminos or Bragg’s liquid aminos as an alternative. Coconut aminos is a dark liquid condiment made from the fermented sap of a coconut palm tree and sea salt. It does not replicate the exact flavor, but it does give you a little salty-savory taste.
Health Benefits
Since it’s a fermented product, it is a good source of antioxidants, protein, and vitamin K. As a soy product, it contains isoflavones; a compound said to reduce menopausal effects and improve cholesterol levels. Some studies show there are more phytonutrient antioxidants in soy sauce than in red wine!
There’s no question that soy sauce is a salty food, but it is lower in sodium than table salt. A little goes a long way, so use sparing.
How to Store
Before Opening
Stor unopened bottles at room temperature. Store in a pantry or dark place and avoid direct sunlight, heat, and humidity.
After Opening
When soy sauce comes in contact with air, it oxidizes and darkens in color, and gradually loses its aroma. To prevent this, make sure to close opened bottles properly.
There’s an ongoing debate whether opened bottles should be refrigerated or stored at room temperature. It’s a shelf-stable product as it’s high in sodium and won’t spoil. While some experts suggest keeping premium bottles in the fridge, it’s ultimately up to you.
Recipes Using Soy Sauce
FAQs
Q: Is soy sauce high in sodium?
Soy sauce does contain high salt levels, but it ultimately depends on how much you add to the dish. You won’t immediately notice the difference but will notice the savory fragrance and flavor. It’s not a salt replacer, so depending on the recipe, you may need to add salt, especially when cooking with meat and vegetables. You can always start with a smaller amount, then add more after tasting the flavor.
Q: Can I use normal soy sauce if I’m on a low-sodium diet?
You could opt for a low-sodium soy sauce. You could also decrease the amount of regular soy sauce and increase aromatics such as ginger, garlic, scallions, or spices to enhance the flavor. Most low-sodium brands are made through chemical production, as it doesn’t utilize fungal cultures.
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