Dried turmeric is made by peeling, boiling, and drying the rhizomes, which are then sold whole or ground. Turmeric loses some of its essential oils and pungency in the drying process but it can still provide warmth and color. For the best flavor use whole fingers and grind them as needed using a microplane or spice grinder.
When purchasing dried turmeric look to ethnic and specialty spice shops that often have fresher stock and faster turnover than regular grocery stores. Aroma is often a better indicator of quality than color, which can vary from yellow to orange. Store turmeric in an airtight container in a cool, dark place for up to a year.