Turmeric is the rhizome or underground stem of a ginger-like plant. It is usually available ground, as a bright yellow, fine powder. The whole turmeric is a tuberous rhizome, with a rough, segmented skin. The rhizome is yellowish-brown with a dull orange interior that looks bright yellow when powdered. It is routinely added to mustard blends and relishes. It also is used in place of saffron to provide color and flavor.