Turmeric finger

Production involves a boiling process, which is followed by exposure of the rhizomes to sunlight for five to seven days to dry. Then they are polished by hand rubbing or by rotation in a mounted drum. Dried rhizomes vary from about 2.5 to 7.5 cm (1 to 3 inches) in length. The spice is usually sold in ground form. Distillation yields 1.3 to 5.5 percent essential oil, the main components of which are turmerone and ar-turmerone. The colouring matter is curcumin, which is also an antioxidant.