soy sauce
Also known as: Soy
A salty, savory, fermented sauce made from soybeans and usually wheat, a foundational seasoning across Chinese, Japanese, and other Asian cooking. Regular (light) soy sauce and dark soy sauce are different products, not just different brand names: dark soy is thicker, slightly sweeter, and used mainly for color and depth rather than as the primary salt source.
Buying guidance
Check which type is wanted, light/regular versus dark, since swapping one for the other changes both saltiness and color noticeably. For a wheat-free diet, tamari is the version to look for, since traditional soy sauce almost always contains wheat.
Substitutions
- Tamari -- nearly identical flavor, brewed without wheat, and the standard swap for a gluten-free need; use cup for cup.
- Coconut aminos -- noticeably sweeter and less salty, so use more to reach an equivalent salt level and expect a milder result.
- Dark soy sauce -- more concentrated and colors a dish more, so use less than an equal swap of light soy would suggest.
Tips & common mistakes
Dark soy sauce contains added caramel or molasses for its color, so it scorches and turns bitter in a very hot pan much faster than the thinner, saltier light or regular soy sauce -- add dark soy a bit later, or alongside other liquid already in the pan, rather than pouring it directly onto bare hot metal.
Storage
Soy sauce is salty and fermented enough to stay safe well past its use-by date without refrigeration, but the more of a bottle that's used up, the more air fills the empty space above the liquid -- that growing headspace speeds up flavor fading toward the end of a bottle, so a smaller bottle used up quickly stays fresher than a large one that lasts a long time.