Effect of High Pressure Treatment on Structural, Functional, and In‐Vitro Digestibility of Starches from Tubers, Cereals, and Beans

Abstract

AbstractStarch from different sources (wheat, rice, corn, waxy corn, potato, sweet potato, and kidney bean) are subjected to high pressure treatment (HPT) at 300 and 600 MPa and are evaluated for changes in digestibility, structural, thermal, and pasting properties. HPT alters the surface of starch granules and significantly disrupts morphology of granules. Increase in average granule size and decrease in relative crystallinity is observed in high pressure treated starches. However, a significant decrease average granule size is observed at 600 MPa. High pressure treated starches show progressive reduction in both swelling power and solubility with increase in pressure. HPT results in reduction in gelatinization temperatures and enthalpy of gelatinization (ΔHgel) while starches except potato starch treated at 600 MPa do not show any endothermic peak indicating complete destruction of crystalline structure. Peak and final viscosity of native starches is higher than those of their counterpart high pressure treated starches except waxy corn starch. Increase in gel firmness and destruction of internal structure of starches especially that of tuber starches treated at high pressures is observed. HPT lowered rapidly digestible starch fraction and increased slowly digestible starch and resistant starch fraction.