Response Surface Methodology for Optimizing Twin‐Screw Prepared Cistanche deserticola‐Potato Composite Rice

Abstract In order to find the best extrusion conditions which can not only satisfy the taste of the public, but also retain echinacoside to the greatest extent, response surface methodology is used to design the reported experiment. Broken rice, potato flakes, and Cistanche deserticola are used as main raw materials to prepare C. deserticola ‐potato composite rice by twin‐screw extruder in this study. Hardness, springiness, content of echinacoside, and sensory score are determined for optimization. The optimum extrusion conditions are obtained as follows: the screw speed is 139 rpm, barrel temperature is 115 °C, and the moisture content is 29%. It is found that C. deserticola ‐potato composite rice with 0.7% of C. deserticola has the most acceptable quality and there are 93.45 mg of echinacoside in every 100 g of rice. The development strategy of potato staple food can be realized better by using potato flakes instead of some rice flour (30%) to recombine rice grains. With the improvement of utilization rate of broken rice, sustainable development can be achieved.