Effect of extrusion on gelatinization degree and protein digestibility of rice flour

Rice flour was chosen as raw material to study the effect of extrusion on gelatinization degree and protein digestility.The effect of material moisture content, screw rotation speed and the fifth area temperature on gelatinization degree and protein digestility of rice flour were investigated through single factor experiment and orthogonal experiment.Based on these above, the results showed the best parameters of rice expansion food was material moisture content of 18%, screw rotation speed of190 r/min, the fifth area temperature of 190 ℃.Under this experiment conditions, gelatinization degree was 90.72%, protein digestility was 82.80%, which was improved by 10.31% in comparison with the protein digestility without extrusion.The study offered certain reference for deep processing of rice.