利用双螺杆挤压膨化机对绿茶茶渣进行挤压膨化加工,采用响应面设计方法建立物料含水量、喂料速度、螺杆转速以及套筒温度与绿茶茶渣中粗纤维含量之间的回归模型。结果表明,各参数对绿茶茶渣中粗纤维含量影响由大到小依次为：螺杆转速>套筒温度>喂料速度>物料含水量,获得低粗纤维含量的最佳挤压膨化参数为物料含水量70%,喂料速度90r/min,螺杆转速90r/min,套筒温度50℃。在此条件下,茶渣中粗纤维含量为15%,与膨化前原料相比,粗纤维含量下降了3%。

Extruded green tea leave processed with a twin screw extruder, using response surface design method to establish the regression model between the moisture content of material, feeding speed, rotational speed of screw, temperature of barrel and the content of crude fiber in the green tea leaves. The results showed that the significance of parameters on the content of crude fiber in the green tea dregs was decreased according to the order of rotational speed of screw>temperature of barrel>feeding speed>moisture content of material. The optimal parameters of low content of crude fiber in the green tea dregs were as follows: moisture content of material 70%, feeding speed rotational 90r/min, speed of screw 90r/min and temperature of barrel 50℃. At this point, the content of crude fiber in the tea dregs was around 15%, compared with the raw materials before extrusion, the content of crude fiber decreased 3%.