Title: Pectin
CAS Registry Number: 9000-69-5
Literature References: Polysaccharide substance present in cell walls of all plant tissues which functions as an intercellular cementing material. One of the richest sources of pectin is lemon or orange rind which contains about 30% of this polysaccharide. Occurs naturally as the partial methyl ester of a-(1?4) linked D-polygalacturonate sequences interrupted with (1?2)-L-rhamnose residues. Neutral sugars: D-galactose, L-arabinose, D-xylose and L-fucose form side chains on the pectin molecule. Structure studies: D. A. Rees, A. W. Wight,
J. Chem. Soc. B 1971, 1366. Secondary and tertiary structure in solution and in gels: D. A. Rees, E. J. Welsh,
Angew. Chem. Int. Ed. 16, 214 (1977). Review and bibliography: Towle, Christensen, in
Industrial Gums, R. L. Whistler, Ed. (Academic Press, New York, 2nd ed., 1973) p 429-461. Book: Z. I. Kertesz,
The Pectic Substances (Interscience, New York, 1951).
Properties: Occurs as a coarse or fine powder, yellowish-white in color, practically odorless, and with a mucilaginous taste. Almost completely sol in 20 parts water, forming a viscous soln contg negatively charged, very much hydrated particles. Acid to litmus. Insol in alcohol or in diluted alcohol, and in other organic solvents. Dissolves more readily in water, if first moistened with alcohol, glycerol or sugar syrup, or if first mixed with 3 or more parts of sucrose. Stable under mildly acidic conditions; more strongly acidic or basic conditions cause depolymerization.
Use: In the preparation of jellies and similar food products: Owens
et al., "Factors Influencing Gelation with Pectin" in
Natural Plant Hydrocolloids, Advances in Chemistry Series (ACS, Washington, 1954) pp 10-15.
Therap-Cat-Vet: Antidiarrheal.
