Defatted rice bran was prepared by solvent extraction in a Soxhlet apparatus using hexane (rice bran: hexane ratio = 1:5w/v), followed by air-drying in a fume hood. The defatted rice bran was mixed thoroughly with five volumes of distilled water. The mixture was adjusted to pH 9 with 1 N NaOH, stirred for 1 h at 30 °C, and centrifuged at 5000g for 20 min. Then, the supernatant was adjusted to pH 4 with 1 N HCl, maintained at 30 °C for 30 min for protein precipitation, and centrifuged at 5000g for 20 min. The solid residues were washed with five volumes of distilled water and neutralized with 1 N NaOH. The neutralized protein solution was spray-dried.