CAS Registry Number: 9000-21-9
Additional Names: Furcellaria gum; Danish agar
Trademarks: Burtonite 44
Literature References: A gum obtained from a seaweed of the Rhodophyceae, the red alga Furcellaria fastigiata, fam. Furcellariaceae, order Gigartinales. The weed is found primarily in Northern European waters, especially in the Kattegat (between Sweden and Denmark). The gum is the potassium salt of the sulfuric acid ester of a high molecular weight polysaccharide. Consists mainly of D-galactose, 3,6-anhydro-D-galactose, and the half-ester sulfates of these sugars; one sulfate group occurs for each three or four monomeric units, which are arranged in an alternating sequence of (1®3) and (1®4)-linked units. Review: Bjerre-Petersen et al. in Industrial Gums, R. L. Whistler, Ed. (Academic Press, New York, 2nd ed., 1973) pp 123-136.
Properties: The processed gum is a white, odorless powder. Sol in hot or warm water. Easily dispersed in cold water to a homogeneous suspension without lumps; the furcellaran particles hydrate, swell and become almost invisible but do not dissolve unless heated. Forms agar-like gels at low concns. The strength of the gel can be increased by adding salts, esp potassium salts. Highly viscous. Solns in neutral medium are not adversely affected by prolonged exposure to high heat. However, exposure to heat in acidic media results in rapid hydrolysis and loss of gelling power.
Use: Natural colloid, gelling agent, viscosity control agent used primarily in food products but also in pharmaceuticals. Also in products for diabetics, proprietaries for reducing excess body wt, toothpastes. As carrier for food preservatives, bactericides. In bacteriological culture media.