Turmeric

Turmeric, the rhizomes of Curcuma longa, a perenial herbaceous plant, belonging to the Ginger family, native to Southern Asia. The ovate tubers are the central portion of the first year's growth, and are known as "bulbs:" the long cylindrical "fingers" are lateral growths. Madras tumeric consists of large round pieces; that from Bengal is darker in colour; and that from Java duller. It is always hard and tough, breaks with a resinous fracture, and ranges in colour from orange to brown. It is cultivated in rich, well-watered soil, an acre yielding 2,000 lbs.; but the exports from India have declined from over 8,000 tons, of which England took half, to 1,400 tons, England taking 226. It has long been used as a condiment, and as a medicine in India, and is an ingredient in curry powder. It is used as an adulterant of mustard; but its employmet as a dye has come to an end. It has an aromatic taste due to an essential oil containing the alcohol turmerol, C₁₉H₂₈O, and its colour is produced by curcumin, C₁₄H₁₄O₄. This substance, when pure, forms yellow acid crystals, and paper dyed yellow by a tincture of turmeric turns brown on being moistened with an alkali, drying violet. It is, therefore, a common laboratory test for an alkali.