Flour Properties of Milky-white Rice Mutants in Relation to Specific Loaf Volume of Rice Bread

Abstract

Starch content, starch damage, particle size distribution, pasting properties measured using a rapid visco analyser (RVA properties) of rice flour, and their relation to specific loaf volume (SLV) of rice bread with gluten were examined in rice cultivar Koshihikari and its milky-white mutant lines. Two different milling methods were used: jet-milling under semidry condition after pectinase treatment and pin-milling under dry condition. Jet-milled and pin-milled milky-white mutants and jet-milled Koshihikari produced flour with low starch damage, fine particle size, low pasting temperature, high final viscosity, large setback, high trough, and long peak time. Such flour resulted in high SLV rice bread. SLV of rice bread from pin-milled milky-white mutant was equivalent to that from jet-milled Koshihikari. Using milky-white mutants, rice flour suitable for bread-making would be produced by dry pin-milling.