Mustard is the ground seed of two species of the Brassica. Brassica alba yields white mustard seeds; Brassica nigra, black mustard seeds. Both species are grown in Europe and America.

• 芥茉是两种芸苔植物的籽研磨品。白质芸苔生产白色芥茉籽，黑质芸苔生产黑色芥茉籽。两种都生长在欧洲和美洲。