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Mung bean starch suspension (9%) was annealed at 55℃ for 0.25-5 hr using Brabender amyloviscograph. Amylose content, swelling power, and solubility decreased as annealing time increased, which was prominent in the first 0.5 hr. They continuously decreased up to 1 hr, but the prolonged annealing time after 1 hr caused only a slight decrease. Annealing resulted in a decrease in park viscosity, breakdown, and final viscosity and an increase in setback and pasting temperature, which was measured with a Rapid Visco Analyser (RVA). Differential scanning calorimetry demonstrated that onset and peak temperatures increased as annealing time increased, resulting in narrower gelatinization temperature range. Gelatinization enthalpy also increased upon annealing. At 55% deformation, the hardness of annealed starch gel (9% solid) was equal to or greater compared with the native starch gel up to annealing time of 3 hr and positively correlated with RVA setback. Although amylose content, swelling power, and solubility were inversely related with various properties of the annealed starches, swelling power was a better index in explaining the change in properties of mung bean starch upon annealing.
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