Effect of debranching and heat-moisture treatment on the properties of Thai rice flours

High and low amylose Thai rice flours (KC and ML, respectively) were used in this work, to increase the resistant starch (RS) content in the flour. Pullulanase debranching followed by heat-moisture treatment (DHMT) altered the pasting properties, which increased the shear stability to the flours. The gelatinisation temperature determined by DSC was increased and the more retrogradation occurred in treated flour compared to the native flour. The SEM observation showed that the treatment did not change the morphology of the granules in both flours. The slowly digestible starch (SDS) content in DHMT KC was higher than in the native KC. The RS content in the treated ML flour was increased to 18.31% from 11.59% in native flour. These concluded that the treatment affected the digestibility, while maintaining the granular structure.