Zingiberaceae Curcuma longa L.
Source: Magness et al. 1971
The plant is a large-leaved herb, closely related to ginger. It is cultivated in tropical countries for the thick, rounded, underground stems or rhizomes, which constitute the spice, turmeric. Turmeric contains an oil, which consists in part of curcumin, which on oxidation is changed into vanillin, the active principle in vanilla. The rootstocks of turmeric, both fresh and dried, are also used as flavoring in curries and other cookery.