Material such as soyabean to be processed, is first passed through magnetic separator and cracker before feeding it into screw hopper, from screw hopper its fed to driven element of extruder via variable speed screw. In extruder, properties of soyabean are changed due to mixing, kneading and cooking action of extruder. There are many variables such as speed, feed, double fly & single fly worm, steam lock sizes etc. to control properties of materials.