Study on optimization of the extrusion processing of resistant starch by response surface methodology

Response surface methodology(RSM)was applied to optimize the extrusion process of resistant starch(RS). A central-composite design(CCD)was used for experimental design and result analysis to obtain the optimal conditions of the productivity of RS. Based on the RSM analysis,the optimum conditions were:water amount 7.5%,rotational speed of screw 592r/min and temperature of die top 150℃. Under the optimized conditions,the productivity of RS was 17.945%±0.523%,which was in good agreement with the value predicted by the model.