From Biosun FFI Wiki

Turmeric, also called “Curcuma” and sometimes spelled "Tumeric", is the dried, ground rhizomes of several species of Curcuma longa, a perennial herb of the Zingiberaceae family. It is a bright yellow powder with a characteristic odor and taste. It is produced by the extraction of dried rhizomes with one or a combination of alcoholic solvents or by extraction of other solvents, and suspension of the residue in vegetable oil. Turmeric in powder form consists of the powdered rhizome or the oleoresin standardized with maltodextrin, usually containing 8 to 9% curcumin.

Turmeric and turmeric oleoresin are unstable in light and in alkaline conditions. Both powder and liquid are susceptible to degradation by oxidation. Turmeric will develop bright yellow to greenish yellow shades and it is used as a replacement for FD&C yellow No. 5.

The major applications for Turmeric are to color pickles, and as an ingredient in mustard and other sauces. It is also used in combination with other colorants such as annatto in cheeses, yogurts, ice creams, salad dressings, confectionery and others.