Turmeric is a bright yellow spice powder that is made from the root of a plant in the ginger family (Zingiberaceae), Curcuma longa. It has been used in Asia for thousands for years as a dye, food coloring, and in Indian traditional medicine. Dried turmeric is prepared by boiling the rhizomes, drying them in a hot oven, and then grinding the dried roots. Like many dried spices, it will lose its potency in about six months, so you should think of rotating your stock.