Gum Karaya

Gum Karaya is a vegetable gum produced as an exudate by trees of the genus Sterculia. Chemically, gum Karaya is an acid polysaccharide composed of the sugars galactose, rhamnose and galacturonic acid. Gum Karaya also known as Indian tragacanth is obtained mostly from Indian plantations of Sterculia urens and smaller plantations of Sterculia villosa. In Sudan, and elsewhere in Africa, Gum Karaya can be obtained from Sterculia setigera.

Karaya trees have a white, papery bark. Flowering period is between December-February, producing an oblong - dark brown seed.

All parts of the tree exude a soft gum when injured. Karaya gum is produced by charring or scarring the tree trunk and removing a piece of bark or by drilling holes into the trunk. The gum seeps from the scars and is collected, washed, and dried. The gum is then graded. A mature tree may yield 1 to 5 kg of gum per season. The Karaya season is throughout the year, although the best time to collect quality material is January to June.

World production of gum Karaya is currently estimated at about 5,500 tonnes per annum and is on a declining trend. India is the only regular producer, overwhelmingly dominating international trade in this gum.