To me, Japan is a land of paradox because although culturally, simplicity is revered, nothing is ever really simple. Soy sauce is a good example. This dark, ubiquitous condiment called shoyu in Japanese cuisine is far more complex than it appears. You probably have no idea from the single requisite bottle on a restaurant table that there actually are five categories of Japanese soy sauce with five more varieties on the contemporary market, each sold according to three grades of quality.
The production of Japanese shoyu is steeped in centuries of tradition. And nearly every township in Japan has its own shoyu brewery. Some still brew it in urns set out in the sun while others use modern factory equipment. But all guard the proprietary secrets of brewing, pressing and blending.
There are only four ingredients in basic Japanese shoyu: soybeans, wheat, salt and koji mold starter. But much like in wine production, differences in the ratio of ingredients and the brewing process bring about variations in flavor and quality. The basic process involves mashing steamed soybeans and roasted wheat with koji, a starter mold used for fermentation. Then, this is mixed with salt water and aged from six months to three years. Finally, pressing extracts the liquid.
Like olive oil pressing, there are several pressings of the moromi mash (soybean-wheat mixture) through cotton filters. The filtered shoyu is allowed to settle and may be pasteurized to stop the fermentation and improve flavor. Then, it is settled again. Soy sauce brew masters also blend shoyu pressings to achieve a particular flavor note.
Here are the five main categories of Japanese shoyu:
Koikuchi-Produced from 50 percent soybeans and 50 percent wheat grain. It can be pasteurized or unpasteurized. Koikuchi is the most commonly produced shoyu in Japan.
Usukuchi-Lighter in color and flavor, this shoyu is made with amazake, a sweet sake made from fermented rice.
Tamari-Darker in color than koikuchi, tamari is made from the run-off of miso paste production. It contains no wheat.
Shio-Light, sweet shoyu made with a higher percentage of wheat and less soybeans.
Saishikomi-Darker than other shoyu because it is made with koikuchi instead of seawater. It is also known as kanro shoyu or sweet shoyu.
New lower sodium soy sauces include Genfen (50% less salt) and Usujio (20% less).
Chemical or Synthesized Soy Sauces
Today, artificial soy sauce products crowd market shelves. Made with acid hydrolyzed soy protein, salt and caramel coloring, these cheaper soy sauce products do not require any lengthy aging or skilled craftsmanship. Not only are these low quality, but some were found to contain carcinogens.
What type of shoyu should you buy?
Read the label to check ingredients. There should be only soybeans, wheat, salt and water. No artificial chemicals. Also, look for the words, "naturally brewed." Color varies between types but generally, high-quality shoyu should not be pitch black but a deep red-brown.
Production of Japanese soy sauce is regulated by the Japanese Agricultural Standard (JAS) which oversees brewing, quality and types. Look for bottles that bear the JAS mark for JAS-compliant quality.
Kongo and Kongo-jozo label grades both contain a mixed ratio of synthesized soy protein and are considered of lower quality. Honjozo grade is 100 % genuine fermented shoyu. Brands of shoyu manufacture several grades so read your label carefully. Beyond this, choose your shoyu type according to its use. Will it be used in a recipe or will it be a table condiment? Taste the different types for yourself and see which you prefer.
1. Soy sauce does not require refrigeration. Its high salt content creates an antimicrobial environment.
2. That high salt/sodium content (up to 18%) can spike blood pressure and negatively affect those who require low sodium diets.
3. Soy sauce contains wheat and may cause allergic reaction in those with wheat allergies or Celiac disease. Tamari sauce, however, is made without any wheat.
4. Although soy sauce is made from soybeans, it does not contain a high level of the isoflavones which are the beneficial components of soy.
5. Other Asian cultures produce their own versions of soy sauce. The Chinese manufacture light, fresh, dark and thick variations of soy sauce. Indonesian soy sauce is called kecap which also comes in several varieties. Koreans produce Joseon ganjang; Taiwainese make a black bean type of soy sauce. In the Philipines, youfll find a milder soy sauce called toyo while the Vietnamese version is called xi dau.
6. In the past decade, some soy sauce imports from Thailand, Taiwan, China and Australia were found to contain carcinogens.
7. The average Japanese person uses about two gallons of soy sauce per year.
8. The United States grows 80 percent of soybeans used to make soy sauce but most Japan boutique soy sauce brewers will only use organic soybeans grown in Japan.