The role of Amomum tsao-ko in seasoning is to enhance fragrance, remove fishy smell and deodorize. Alpinia katsumadai, also known as Alpinia hainanensis, is a perennial herb with a height of 3 meters, banded leaves, a tapering top, a curled tail, a tapering base and no hair on both sides. The fruit is spherical, about 3 cm in diameter, and golden yellow at maturity.