Structure-dependent modulation of potato and corn starch gelatinization and retrogradation by Salecan

Starch retrogradation is a critical technological challenge requiring effective mitigation. This study aimed to systematically compare how Salecan, a novel food-grade linear anionic glucan, differentially modulates gelatinization and retrogradation of potato starch (PS) and corn starch (CS) based on structural differences. Salecan reduced pasting viscosity, swelling power, and viscoelasticity of PS but increased these properties for CS, indicating structure-dependent gelatinization regulation driven by electrostatic repulsion and hydrogen bonding, respectively. During retrogradation, LF-NMR, XRD, and FTIR analyses revealed that Salecan significantly decreased gel hardness, retarded water migration, lowered relative crystallinity, and reduced short-range order in both starches; SEM revealed distinct microstructural changes. In vitro digestion indicated Salecan inhibited hydrolysis of gelatinized starch but promoted that of retrograded starch. These divergent effects appear associated with inherent starch structural properties (granule size, surface charge, and amylose content), offering potential insights for targeted tailoring of starch-based foods through polysaccharide modification.