Study On The Extrusion Of Wheat Bran And The Influence On The Main Ingredient Of Wheat Bran

A high dietary fiber convenience food, based on wheat bran and flour as raw material, was developed by SLG32-II twin-screw extruder. Through the extrusion, the wheat bran have do away with its bad odor, to become nutrition and convenient produce that is good flavor and stored up. Also it raises the economic value of wheat bran.Through the main ingredients of wheat bran assaying before-and-after extruding, it shows that extrusion treat reduces the content of phytic acid, starch, crude fat, crude fiber, reducing sugar and free amino nitrogen in wheat bran, and also raises the content of total sugar and water-solution total sugar in wheat bran, but not effect the content of crude protein and ash. After reseaching the effects of varying extruding parameters on the content of reducing sugar, free amino nitrogen, water solubility total sugar and the degradability of phytic acid. It shows that the degradability of phytic acid is great influenced by screw speed, moisture content, barrel die temperature; water solubility total sugar is great influenced by screw speed, barrel die temperature, content of flour; reducing sugar and free amino nitrogen is great influenced by screw speed, content of flour, moisture content. Through the vitrodigestbility and composition determination of starch and protein in wheat bran before-and-after extruding, it shows that extrusion treat not only make raise the content of glutnin and alcohlyso protein but also reduce the content of albumin, globulin and insoluble protein. And it also shows that both the vitrodigestbility of starch and protein is improved.Use response surface methodology to study the effects of process parameters on the degree of puff, water solution index, water absorption index of the extrude product. Parameters examined are: screw speed, content of flour, moisture content, barrel die temperature. The most proper technology is that screw speed is 200rpm, content of flour is 20 %, moisture content is 40%, barrel temperature in the last zone is 140℃.