Physicochemical characteristics of rice flour gelatinized by drum-drying

Gelatinized rice flours were prepared by drum drying at different moisture contents of slurry made from dry milled and wet milled rice flours. Milled rice samples were prepared from the Chuchung and the Samgang varieties. Degree of gelatinization of drum-dried rice flours revealed over 92% at 60% moisture content of wet milled rice flours and 80% moisture content of dry milled ones. With regards to amylogram and rheological properties, drum-dried rice flours prepared from wet milled raw materials showed higher viscosity than from dry milled ones. Increasing water contents in the slurry increased water absorption index(WAI) and decreased water solubility index(WSI). Hunter's color values of drum-dried rice flour at high moisture contents showed higher L values and lower b values. For the preparation of gelatinized rice flours by drum drying process, the higher water content caused more gelatinized network structure of rice starch in scanning electron micrographs. With regards to farinogram properties of dough with drum-dried rice flours and wheat flours in mixing ratio of 1 to 9 by weight, drum-dried rice flours made from wet milled raw rice flours revealed higher MTI than from dry milled ones.