Technology Optimization for the Extrusion Rice Bran with Topsis and Z-points Evaluation Method

Using Topsis and Z-points comprehensive evaluation analysis method, this paper analyzes the qualities of rice bran by extrusion processing and study the optimize technology conditions of the extrusion process. The results showed that the extrusion temperature, extrusion speed and raw material humidity have significantly influence to the rice bran fat quality(P 0.05), The effect of difference extrusion conditions showed the decreasing order: material moisture extrusion temperature extrusion speed. The best extrusion conditions is extrusion temperature 160 ℃, material moisture 22 %, extrusion speed of 700 r/min. Compared with the glucose group,the fatty acid value, peroxide value, lipase activity and bacterial count decresed 89.1 %, 60.9 %, 95.2 % and 88.3 %, and the crude protein, γ-oryzanol, vitamin E compared increased 3.8 %, 18.9 %, 17.1 %. Extrusion processing improved the fat stability, nutrition and health safety of rice bran, and effective improve its use value.