Effect of heat moisture treatment on physicochemical characteristics of brown rice flour (<i>Oryza nivara</i>) of local cultivars <i>Paeuwamomea</i>

Abstract This study was aimed to improve the physicochemical properties of the brown rice flour ( Oryza nivara ) of a local cultivars Paeuwamomea through a heat moisture treatment (HMT). The analysis was performed by testing the swelling power, solubility, viscosity, pasting properties, functional groups, pattern analysis of crystalline starch, and the morphology of the starch granules before and after the modification process. The results showed that HMT modification at the heating of 70°C for 5 hours had a relatively better characteristic, that was a swelling power of 14.54 g/g, water solubility index of 14.81 %, and viscosity of 17.74 cP. With HMT modification, pasting temperature increased; but peak, breakdown, final and setback viscosities decreased significantly. X ray diffraction and scanning electron micrograph analysis indicated that HMT treatment may have altered the starch’s crystalline and morphology structures. These results demonstrated the improvement of the characteristics of brown rice flour through HMT modification.