Guar gum
Description
Gum guar is obtained from the seed of the guar plant Cyamopsis tetragonoloba grown commercially in India and the United States. Guar is a yellowish-white powder which is dispersible in hot or cold water. The water-soluble portion (approx. 85% by wt.) is called guaran and consists of polysaccharides of mannose (63%) and galactose (35%) and about 5-7% wt. of protein. While guar gum has been locally used for centuries in India and Pakistan, it has only been marketed commercially in the past 30 years. It has eight times the thickening power of Starch. Aqueous solutions of guar have a neutral pH and may be turn into a gel by the addition of small amounts of Borax. Guar gum is used as dye solution thickeners in textile printing, for texture and stabilization in food products and as a strengthener in paper.
Synonyms and Related Terms
Cyamopsis tetragonoloba; goma guar (Esp.); guar flour; gum guar; gum cyamopsis; guaran; cyamopsis gum; Burtonite V-7; Jaguar; Guarem; Indalca AG
Risks
- Nontoxic.
- Fisher Scientific: MSDS
Physical and Chemical Properties
- Soluble in water (pH of 1.0% solution = 5.5-6.2).
- Insoluble in oils, greases, hydrocarbons, ketones, esters.
- CAS = 9000-30-0
Resources and Citations
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 4602
- The Dictionary of Paper, American Paper Institute, New York, Fourth Edition, 1980
- John S. Mills, Raymond White, The Organic Chemistry of Museum Objects, Butterworth Heineman, London, 2nd ed., 1994
- I.W. Cottrell, J.K. Baird, gums chapter