Different interaction behaviors of rice glutelin with amylose and amylopectin within starch under the extrusion...

Effects of rice glutelin (RG) on structural properties of amylose (AM) and amylopectin (AP) within rice starch and their interaction mechanism were revealed. At the same RG addition, AP had a greater binding capacity than AM. Adding RG increased the thermal stability and short-range orders of extruded amylose (EAM) and extruded amylopectin (EAP), as well as changed their surface morphologies. Extrusion destroyed the crystalline structure of AM and AP, while the relative crystalline of EAM and EAP increased with the increasing of RG. When RG content was 6 % and 8 %, RG mainly interacted with AM and AP via hydrogen bonds. The main driving force between RG and AP changed into hydrophobic interaction when RG content was 10 % and 12 %. These results contributed to a deep understanding of structural evolution of AM and AP within rice starch caused by the interaction with RG under the extrusion environment.