Comparison of properties of indica and japonica amorphous rice flours produced by shear and heat milling machine

In this study, the shear and heat milling machine (SHMM), which was developed to produce amorphous rice flour, was applied to indica and japonica rice varieties. The grain shape of indica rice differs from that of japonica rice. We examined the effect of shape differences of rice grains on amorphization by SHMM. Pre-crushed samples were also used alongside the rice grain samples to control for differences in grain shape between indica and japonica rice varieties. Rice flour was produced from indica and japonica rices, and the effect of milling temperature at 80, 100, 120, and 140 °C on amorphization was examined. Crystallinity, moisture content, and particle size distribution were compared between the rice varieties. The effect of milling temperature on indica rice was qualitatively similar to that of japonica rice. The longer grain shape of indica had a negative effect on amorphization by SHMM.