| Rice bran was separately stored in ventilated environment at room temperature (18±2）℃ and high temperature with high humidity environment（temperature 50℃, humidity 70%）,and the contents of crude fat, crude protein of the two kinds of rice bran and the acid values, peroxide values and color of the solvent extracted crude rice bran oils were detected to study the effect of storage conditions on the qualities of rice bran and crude rice bran oil.In addition, the impact of storage conditions on the bleaching effect of crude rice bran oil was studied through adsorption bleaching experiment. The results showed that the content of crude fat in rice bran decreased while the content of crude protein increased under the two types of storage conditions; with storage time prolonging,the color of solvent extracted crude rice bran oil changed a bit in the ventilated environment at room temperature, the peroxide value increased slightly, and the color of bleached rice bran oil was close to the second grade rice bran oil of the national standard after ten days’storage of rice bran. After six days’ storage at high temperature with high humidity, the acid value of the solvent extracted crude rice bran oil increased greatly for the moldy and rancidity of rice bran, in the same time, its peroxide value reduced, its color became dark brown with unpleasant mildew,the pigments were hard to be removed from the oil and its color could not reach the requirement of the fourth grade rice bran oil of national standard even if the dosage of activated clay was 13% in the process of adsorption bleaching. |
