Polysaccharide gums, distribution

Table I. Distribution of Polysaccharide Gums by Commercial Usage...

Food-grade CMC is a cellulose carboxylic acid ether with an optimum DS = 0.4-0.7. The higher the DS within this range, the more hydrophilic is the polyanion. Uniformity of substitution makes CMC more compatible with dissolved salts and less inclined to thixotropy than uneven distribution (Feddersen and Thorp, 1993). This gum does not precipitate from a 50% ethanol solution. Below approximately pH 4 in water, the polyanions revert to the un-ionized, water-insoluble acid. CMC viscosity-hysteresis has already been described (Fig. 2 in Chapter 3). CMC dispersions and films have the extra advantage of transparency relative to many other polysaccharide dispersions. The films are resistant to oils, grease, and organic solvents (Hercules, Inc., 1980). 

Another Cassia seed gum which has been modified is Cassia occidentalis (CO) Linn. Kasondi is a common herbaceous annual weed that grows throughout India up to an altitude of 1500 m (101). Every part of the plant is used in different applications in the Indian Ayurvedic system of medicine. The pods are 10-13 cm long and up to 0.8 cm in diameter and contain dark olive green seeds. The C. occidentalis seeds are a rich source of galactomannan (w 30% endosperm) [102]. The structure of the backbone of the seed polysaccharide has (3(1—>4) linked D-mannopyranose with random distribution of a(l—>6) linked D-galactopyranose units as side chain (M/G 3.1) (103-105). C. occidentalis seed gum has potential use because of its wide availability. The modification of the C. occidentalis gum chemically via carbamoylethylation under a variety of conditions has been attempted in order to improve its solubility. 

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