Thai cooking and Thai traditional medicine (samunphrai — สมุนไพร) share an herb vocabulary that is largely inseparable. The same lemongrass used in tom yam is prescribed by traditional Thai medicine for digestive complaints; the same galangal used in every Thai curry is the medicinal treatment for nausea and digestive disorders; the same kaffir lime is used in traditional hair treatments. The cooking tradition and the medicine tradition emerged from the same body of knowledge.
The major Thai culinary herbs — their aromatic profiles and documented properties. **ตะไคร้ (Takrai — Lemongrass):** The most widely used Thai aromatic — its primary compounds (citral, specifically geranial and neral) produce the distinctive lemony-herbal note. The lower white stalk only — the upper green leaves are too tough and produce a more medicinal, less food-appropriate flavour. Bruised whole for soups (released, then removed); sliced extremely fine for salads; ground in the mortar for pastes. [VERIFY active compounds] **ข่า (Kha — Galangal):** Not a substitute for ginger — a completely different plant (Alpinia galanga) with completely different flavour compounds (1,8-cineole/eucalyptol, galangin). The medicinal, slightly pine-adjacent character of galangal is fundamental to tom kha — ginger cannot replace it without changing the dish's identity. Young galangal is milder and used for curries; old galangal is more intense and used for medicinal preparations. **ใบมะกรูด (Bai Makrut — Kaffir Lime Leaves):** The double-leaf structure (two leaves joined tip to stem) releases a specific compound (citronellal) that is the most volatile of Thai aromatics — destroyed by heat almost instantly. Used in soups (added at the very end, sometimes raw); torn rather than cut (tearing releases more volatile compounds from the leaf's oil glands); never cooked in curry paste (where the peel, not the leaf, is used). **กระชาย (Krachai — Fingerroot):** The most distinctly Southeast Asian aromatic — rhizomes with a specific musty-camphor-ginger compound profile used in fish curries and stir-fries. No equivalent in any other culinary tradition — fingerroot with fish is a specifically Thai aromatic combination.
THAI CULINARY TRADITION — DEEP EXTRACTION