Influence of extrusion system parameters on resistant starch in barley for beer brewing process

To reduce the content of resistant starch,laboratory researches were carried out on the parameters of extrusion system,for example,diameter of die nozzle,barrel temperature,material moisture,screw speed and the distance between screw end and template inner surface.To acquire the best parameters,the method of five-factor and five-level quadratic orthogonal rotating combination design was applied,and 36 extrusion barley samples were acquired.By application of the American Cereals Association measuring method,the content of re-sistant starch in barley extrusion expansion was measured to find out the rules that how extrusion system para-meters had influenced the resistant starch in barley.Researches indicated that appropriate extrusion parameter could greatly decrease the resistant starch in barley.