Impact Damage on Rough Rice
‘Lemont’ and ‘Rico’ rice were harvested at 17-19% moisture content and then dried to 10.7-11.5% for storage. Impact damage on rough rice was evaluated as a function of variety, cylinder peripheral speed, grain moisture, and number of passes through the thresher. Grains broke more rapidly at higher than at lower moisture levels. Dehusking of the grain increased with an increase in cylinder peripheral speed and the number of passes through the thresher. The highest percentage of unfissured brown rice was obtained at the lower moisture levels. At the intermediate speeds, fissured rough rice grains generally contributed more to breakage than the unfissured rough rice. Some impacts are sufficient to fissure a good grain without rupturing its hull to give brown rice.