Physicochemical properties of sonicated mung bean, potato, and rice starches

Mung bean, potato, and rice starch solutions (5%, w/w) were sonicated for up to 5 min after heating, and their physicochemical properties were investigated. Alkaline viscosities, including the apparent and inherent viscosities of starches, decreased. The residues of the swollen starch granules after pasting and centrifugation were also reduced prominently by sonication. Average degree of polymerization did not change with sonication. The starch paste became more transparent, and the hot paste viscosity measured at 70degreesC decreased remarkably. Results indicate that changes in the physicochemical properties of starch were induced by the disruption of swollen granules rather than the breakage of glucosidic linkages with sonication.