Krachai — Boesenbergia rotunda, known as Chinese keys or fingerroot — is a rhizome of the ginger family with a distinctive medicinal, camphor-fresh aromatic profile. It is less widely known than galangal and ginger outside Southeast Asia but is essential to several specific Thai preparations: jungle curry (Entry TH-37), nam ya sauce (Entry TH-44), and certain fish preparations where its camphor-clean note is intended to cut through the fish's stronger aromatic.
**Aromatic compounds:** Pinocembrin and pinostrobin (flavonoids), cineole (camphor-eucalyptus), and several other sesquiterpenes — producing a fresh, medicinal, camphor-adjacent note with a slight peppery bite. **Comparison to galangal:** Both have a medicinal-resinous quality. Krachai is sharper, more camphor-fresh and slightly more bitter. Galangal is deeper and more resinous. They are not substitutable — their flavour contributions differ significantly. **Preparation:** - Peel (the skin is thin and rough — scrape rather than peeling with a vegetable peeler). - Slice thin or pound with other paste ingredients. - Used either in the paste (jungle curry) or as thin slices added to the dish during cooking (certain fish soups and steamed fish preparations). **Availability:** Fresh krachai is found in Asian grocery stores. Frozen krachai is increasingly available and retains more of the fresh aromatic character than dried.
David Thompson, *Thai Food* (2002); *Thai Street Food* (2010)