Sumac: Tartaric Acid as Souring Agent

Sumac — the dried, ground berry of Rhus coriaria — is the primary souring agent of Levantine cooking, predating the introduction of citrus to the region. It appears throughout Jerusalem's recipes as a finishing spice, a marinade component, and a table condiment. Its tartaric acid content makes it function differently from citric acid (lemon) or acetic acid (vinegar) — providing tartness with a fruity, astringent depth that neither can replicate.

A dark red spice ground from dried sumac berries, used as a souring agent and flavour component. Unlike lemon juice it is dry, meaning it seasons without adding moisture — it can be used in spice rubs, dry marinades, and finishing dustings without affecting the texture of what it seasons.

• Tamarind (same souring agent role in South and Southeast Asian cooking, different flavour), Amchur (dried mango powder — same dry-acid principle in Indian cooking), Verjuice (same tartaric acid family

Sumac on roasted chicken or lamb acts as a brightness agent — it cuts through fat and richness the way lemon does but with additional fruity complexity. On fattoush it is both seasoning and defining flavour. Its colour is part of its appeal — the deep red dusting over white labneh or pale hummus is intentional contrast.