ABSTRACT
Curdlan is a polysaccharide produced by microbial fermentation having thermal gelling properties. The use of curdlan has been studied in areas other than food, e.g., pharmaceutical and industrial chemical applications. Curdlan is insoluble in water, alcohol, and most organic solvents. Curdlan is soluble in aqueous systems having a pH of 12 and higher due to dissociation of hydroxyl groups within the molecule. Stable aqueous suspensions of curdlan can be obtained by suspending curdlan in water followed by vigorous mechanical mixing with high shear. The low-set curdlan gel has been reported to be a result of hydrogen bonds between curdlan micelles, while the ultra structure of the high-set gel results from water entrapment within a three-dimensional network consisting of curdlan micelles linked by hydrophobic bonds. The strength and structure of the curdlan gel is maintained even after the freeze-thaw cycle, even though some syneresis is observed.
