Controlling sodium chloride concentration modulates the supramolecular structure and sol features of wheat...

The sol performance of wheat starch (WS) matrix incorporating acetylated starch (AS) is crucial for the processing and quality features of wheat products. From a supramolecular structure view, how regulating salt (sodium chloride) concentration modulates the sol features, e.g., pasting, zero-shear viscosity (ZSV) and thixotropy of WS-AS binary matrix was explored. Compared to the salt-free counterpart, the saline matrices exhibited a delayed pasting profile and a decreased viscoelasticity. Thereinto, the sol at 0.02 M NaCl exhibited the smallest ZSV (23,710 Pa·s) and the greatest in-shear recovery ratio (33.7 %). Such variations could be attributed to the weakened coil-helix, nematic-smectic and isotropy-anisotropy transitions from a side-chain liquid-crystalline perspective. Meanwhile, the correlation length (ξ) and radius of gyration (R_g) obtained from small angle X-ray scattering analysis were increased by 5.2 and 9.6 Å respectively, which disclosed a restrained entanglement and an enhanced chain mobility. These results would provide a reference for the design of fluid/semisolid products with optimized qualities.