Herein, some physicochemical, rheological, and textural properties, as well as retrogradation kinetics of native wheat starch (NWS) gel in the presence of sage seed gum (SSG) and whey protein concentrate (WPC) were investigated. The substitution of NWS with SSG increased the swelling power of starch granules, viscosity, and pseudoplasticity of NWS gel, while the NWS replacement with WPC decreased the swelling power and viscosity of NWS gel. SSG had an outstanding effect on reducing the syneresis of NWS gel during storage at 4 °C and −18 °C, indicating the improvement of cold storage stability of starch gel. From the back-extrusion test, it was found that substitution of NWS with SSG enhanced hardness, cohesiveness, adhesive force, and adhesiveness of starch gel, while these textural attributes were weakened by substitution of NWS with WPC. The SSG effect on retrogradation behavior of NWS gel was concentration-dependent and it retarded the retrogradation of NWS gel at the 5% substitution level. The NWS substitution with WPC reduced the retrogradation kinetics rate, which was more pronounced at the 10% substitution level. However, it was proved that the interactions of SSG and WPC led to a noticeable decrease of retrogradation kinetics rate, indicating the significant retarding effect of these blends on the NWS retrogradation rate. These results show that although WPC weakened the starch network, it had a positive effect on restricting the retrogradation process of NWS gel. As a result, a suitable mixture of NWS-WPC-SSG could effectively improve the functional properties of the starch gel.

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