Organic Yellow Mustard Seeds (Brassica Juncea) is called Pilli Sarson in Hindi. It is harvested from mid February to mid April and has a warm, earthy and pungent taste. They are tiny black seeds in appearance and have a warm, earthy and pungent taste. Powdered mustard is simply finely ground mustard seed. In powdered form, mustard has no smell when dry, but it has a hot flavor when mixed with water.