Coriander

Origin

Coriander is one of the oldest cultivated herbs — seeds have been recovered from Egyptian tombs (Tutankhamun’s, among others) and Bronze Age Greek caves. The plant grew wild across the eastern Mediterranean and Levant before being carried east through Persia and Arabia to India and west through Spain to the New World.

The remarkable thing about Coriandrum sativum is that it produces two distinct kitchen ingredients from the same plant. The leaf (cilantro, fresh coriander) and the seed (whole or ground spice) have entirely different flavour profiles and entirely different culinary roles.

Sensory profile

The leaf and seed share a Latin name and almost no aromatics. Cilantro leaves carry decanal and dodecenal — aldehydes that some people perceive as fresh and citrusy and roughly 25% perceive (via the OR6A2 olfactory receptor variant) as soap or metal. The split is genetic, not learned. Cuisines that depend on cilantro — Mexican, Thai, Vietnamese, Indian — generally formed in populations with lower OR6A2 frequency.

The seed is dominated by linalool, the same compound that gives basil and lavender their floral edge, plus α-pinene and γ-terpinene. The flavour reads warm, slightly citrus-resinous, sweet on the back palate. Lightly toasting the seed releases the aromatics; long-toasted seed turns harsh and one-note.

In the kitchen

Cilantro leaf: Mexican salsa, Thai yam, Vietnamese phở garnish, Indian chutney, Levantine tabbouleh (in Lebanese style) — almost always added raw, at the last moment, and never cooked.

Coriander seed: Indian garam masala, Ethiopian berbere, North African ras el hanout, Belgian witbier (the wheat beer style requires it), and the spice base of Latin American adobo. Toast whole seeds in a dry pan for 30 seconds before grinding.

The two ingredients almost never appear in the same dish in the same culinary tradition. Cilantro is for the herb plate; the seed is for the spice grinder.

How to handle

Cilantro: buy with roots attached if possible (this is the southeast Asian standard — root has more concentrated flavour than leaf). Store stems in a glass of water, leaves loosely wrapped, in the refrigerator. Wash and chop just before use; cilantro browns quickly when cut.

Coriander seed: buy whole seeds, never pre-ground. Toast in a dry pan over medium heat for 30 seconds until fragrant; grind with mortar or spice grinder. Pre-ground coriander seed loses its aromatic top notes within a month.

References

• Davidson, Alan. The Oxford Companion to Food (Oxford UP, 2014) — coriander in ancient food trade.
• Eriksson, Nicholas, et al. “A genetic variant near olfactory receptor genes influences cilantro preference.” Flavour 1.1 (2012) — the OR6A2 study.
• Roden, Claudia. The New Book of Middle Eastern Food (Knopf, 2000) — Levantine herb traditions.