Abstract: The effects of curdlan gum (CG), konjac gum (KGM), sodium alginate (SA) and xanthan gum (XG) on physicochemical properties, eating quality and digestibility of extruded reconstituted rice were compared in this study. The results showed that reconstituted rice with CG was regular and glossy in appearance, and had lower gelatinization viscosity and digestibility, the lowest short-range order and crystallinity and better retrogradation resistance as well as moderate hardness, non-sticking to teeth and the highest sensory score after cooking. Reconstituted rice with KGM had a smooth surface, the best digestion resistance and moderate retrogradation resistance, gelatinization viscosity not significantly different from that of the control without added hydrophilic colloid, soft texture and the second highest sensory score after cooking. The gelatinization viscosity of reconstituted rice with SA was slightly increased and the digestibility was decreased, but the resistance to retrogradation was moderate and the surface was rough, and the rice was soft and sticky after cooking, with the worst taste. The addition of XG provided reconstituted rice with the highest elasticity and gelatinization viscosity, but reconstituted rice with XG was irregular in appearance, with a rough surface, poor resistance to digestion and retrogradation, and was sticky scored low in sensory evaluation after cooking. In addition, the addition of hydrophilic colloids effectively improved the water stability of reconstituted rice and reduced the cooking loss and water absorption and expansion rate after cooking, and the color of reconstituted rice with hydrophilic colloids was white with a tingle of yellow. The results of this study provide a theoretical reference for the development of high-quality extruded reconstituted rice.

Key words: extruded reconstituted rice; hydrophilic colloid; eating quality; digestibility; physicochemical properties