... , crispy rice, breakfast cereal and the denaturalization starch. 1. Suitable model for snacks food: double-screw extruder65-III, 70-II, 85-II2 ... .Suitable model for pet food:double screw 65—III,70-II,85—I3 ... .Suitable model for tissue protein:double screw 65—IV,double screw 85—III ...