Contents

Soybeans and wheat fermented with Aspergillus oryzae mould and a salt brine, over months. It supplies salt and glutamate at once, which is why it seasons a cold dish more completely than salt alone.

Brewed versus chemical

Read the ingredient list. Traditionally brewed soy sauce lists soybeans, wheat, salt and water. "Chemical" or acid-hydrolysed soy sauce is made in days by boiling defatted soy meal in hydrochloric acid, then neutralising it, and usually declares hydrolysed vegetable protein, corn syrup and caramel colour. It is harsh and one-dimensional. The price gap is small and the quality gap is not.

Types

Type Character Use
Japanese koikuchi (Kikkoman-style) Balanced, ~50 % wheat, aromatic The default
Usukuchi (light) Saltier, paler — lighter in colour, not in salt When colour matters
Chinese light (生抽) Saltier, thinner Seasoning, dressings
Chinese dark (老抽) Thicker, molasses, less salty Colour in braises
Tamari Little or no wheat, rounder Usually gluten-free — check
Shoyu Japanese generic term

In cold food

Soy sauce is the salt in every East Asian dressing here. The base ratio worth memorising: 3 parts soy : 2 parts rice vinegar : 1 part toasted sesame oil, plus sugar, garlic and ginger to taste.

Because it is salty rather than merely savoury, season the rest of the bowl after the dressing, not before.

Gluten

Standard soy sauce contains wheat. Tamari is the usual gluten-free alternative, but not all tamari is wheat-free — the label is the only authority.

Keeping

Years unopened. Refrigerate after opening: it does not spoil, but the aroma compounds oxidise and flatten within a few months at room temperature.

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