Effect of Different Rotational Speeds of the Extruder on the Structure of Corn Starch

In this study, corn starch samples that are treated at different rotational speeds (native corn starch, 5, 15, 25, 35, and 45 Hz) are prepared by twin-screw extrusion, and the structure of corn starch is evaluated. The results show that the crystallinity, degree of order, and degree of the double helix of corn starch decrease with increasing screw speed. In addition, in the gelatinization performance test, the rotational speed is found to have a substantial effect on the peak viscosity, breakdown viscosity, final viscosity, and rebound viscosity. With increasing screw speed, the long-branched chain of the corn starch sample changes into short branched chains, and the molecular weight distribution width index increases continuously. This study provides a theoretical basis for the large-scale extrusion of corn starch.

Automated summary

This study investigates the structure and properties of corn starch treated at different rotational speeds using twin-screw extrusion. The results show that increasing screw speed decreases the crystallinity, degree of order, and double helix of corn starch. Moreover, the rotational speed significantly affects the gelatinization performance of corn starch. The findings provide a theoretical basis for large-scale extrusion of corn starch.