Effect of high hydrostatic pressure on physicochemical, thermal and morphological properties of mung bean (Vigna radiata L.) starch

Mung bean starch-water suspension was subjected to high pressure treatment at 120, 240, 360, 480 and 600 MPa for 30 min, and changes in the structure, morphology and some physicochemical properties were investigated. Light transmittance, swelling power and solubility decreased after the high hydrostatic pressure treatment. A significant increase in the peak viscosity, trough viscosity, final viscosity, pasting temperature and setback, and decrease in breakdown viscosity with increase in pressure treatment was observed. The differential scanning calorimeter (DSC) analysis showed a decrease in gelatinization temperatures and gelatinization enthalpy upon high pressure treatments. The X-ray analysis showed that high hydrostatic pressure (HHP) treatment converted starch that displayed the C-type X-ray pattern to the B-type-like pattern. The HHP treatments altered the shape of starch granules and changed their surface appearance according to SEM analysis. HHP treatment (600 MPa, 30 min) caused a completely gelatinize of mung bean starch.