Study on physicochemical properties and anti-aging mechanism of wheat starch by anionic polysaccharides

The anti-aging effects of two anionic polysaccharides AG (sodium alginate)/SSPS (soluble soybean polysaccharide) and WS (wheat starch) were evaluated, and their different mechanisms were explored. The rheological properties, gelatinization properties and aging properties were characterized. The addition of AG and SSPS changed the gelatinization parameters of WS, decreased the peak viscosity, breakdown viscosity and setback viscosity, and enhanced the fluidity of the gel system. Additionally, the starch molecular orderliness experiment showed that the relative crystallinity of starch gels decreased with the increase in AG and SSPS concentrations, indicating that the rearrangement of amylopectin was disturbed, which inhibited the cross-linking of starch molecules. The water state analysis showed that the hydrophilicity of AG and SSPS and their interactions with starch molecules influenced the relaxation behavior of water protons in the gel system in a concentration-dependent manner. In conclusion, the addition of AG and SSPS could significantly inhibit the aging of WS gels, probably due to the competition effect of AG and SSPS on water and the interaction with starch molecules. The present study results would provide new theoretical insights into WS-based food research.