PHYSICOCHEMICAL PROPERTIES OF MUNGBEAN STARCH ISOLATED BY USING DIFFERENT CHEMICALS FOR PURIFICATION

Abstract

The objective of this study was to determine changes in starch recovery efficiency, chemical composition, shape, and physicochemical properties of mungbean starch when using different chemicals for purification. The mungbean variety named DX044 grown in Vietnam was used for isolating its starch using wet milling method with addition of soaking solution of 0.2% Na₂SO₃, 0.1% NaOH or 0.15% NaHSO₃ before rinsing with distilled water 3 times, drying, grinding, and sifting…The results show that the ability to remove protein and fat of samples using NaOH and NaHSO₃ was much better than using distilled water and Na₂SO₃ resulting in higher starch recovery efficiency. In while, the color of starch was markedly improved for the sample with NaHSO₃ assistance as compared to the others. Shape, size, swelling power and gelatinization properties were inconsiderably changed for the samples using NaHSO₃, water and Na₂SO₃, while the sample with NaOH assistance noticeably changed these properties (p<0.05). Thus, the recovery efficency, chemical composition, morphology, and physicochemical properties of mungbean starch were found to be significantly affected by using NaOH và Na₂SO₃. The using of NaHSO₃ for isolation is the best way which did not affect the physicochemical properties of mungbean starch compared with distilled water.