Gra chai is a Thai term which means chinese keys
Gra-chai as the Thai people know it, has a misleading name that makes it sound like it originated from China . As far as I know, gra-chai is not used in Chinese cooking. Gra-chai roots are used to tame fishiness or meat odor. It also enhances the flavor of fish dishes. The brown skin is scraped away before use. Gra-chai can be bought frozen, dried and powder. Frozen gra-chai is as good as fresh.
List of books: Gra,chai