Bean Flour under Pressure: Probing the Techno-Functionality Through Processing-Structure-function Analysis.

High pressure processing (HPP) was employed to modify the structural make-up of starch and protein in bean flour to ultimately alter the techno-functionality of the flour. Aqueous bean flour dispersions (20 % solid content (w/w)) were processed at pressures ranging from 250 to 600 MPa for 3 min. The results indicated that HPP modified the morphology of starch granules with a decrease in relative crystallinity as a function of pressure. Pressure-induced changes in the secondary structure of bean flour protein were indicative of protein denaturation. The effect of HPP on bean flour techno-functionality was noted in the Rapid Visco-Analyzer test, where a significant decrease in the peak viscosity was observed for flour processed at 600 MPa. The water absorption index of HPP (600 MPa) flour was higher than the one recorded for all other pressure processed flours. Conversely, pressure processing did not alter the water solubility index of the flours.