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Heat treatments were applied to examine the effects on the physicochemical properties of defatted rice bran. The applied heat treatments were general heating at 100℃ for 1 h, autoclaving at 121℃ for 1 h, toasting at 150℃ for 1 h, and extrusion at 110℃ and 350 rpm. Heat treatments increased soluble dietary fiber (SDF) content and decreased insoluble dietary fiber (IDF) content of defatted rice bran. The particle sizes of dry heat treatment sample (toasting) were larger than those of wet heat treatment samples (general heating, autoclaving, and extrusion). The wet heat treatments increased the water solubility index, water absorption index, and water holding capacity but decreased the oil holding capacity of defatted rice bran. The wet heat treatments caused the increase of the bulk density, hydration time, and swelling of defatted rice bran. The heat treatments reduced the lightness, and increased the redness and yellowness of defatted rice bran. The wet heat treatments reduced the yellowness. SEM showed the irregular and collapsed surface of defatted rice bran after heat treatments. The starch granules within the bran seemed to be gelatinized, and the cell wall structure seemed to be modified by the heat treatments.
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