Abstract: 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%.

Key words: extrusion, green tea dregs, crude fiber