Hydroxyl number-dependent polyphenol interactions in purified starch and whole potato flour systems

This study comparatively investigated the divergent structure-activity relationships of polyphenols in potato starch (PS) versus whole potato flour (WPF) matrices. Rheology indicated polyphenols enhanced storage (G') and loss (G″) modulus in WPF but reduced them in PS, with myricetin having the strongest effect. Polarized light microscopy showed that the complexity of the matrix transforms the crystallization of myricetin from dense aggregates in PS to dispersed microcrystals in the WPF. Fourier transform infrared, X-ray diffraction, and ¹³C solid-state nuclear magnetic resonance further demonstrated that the interaction between multi-component and polyphenols changed helical conformation proportions, increasing amorphous regions while decreasing double helices, with myricetin having the most significant effect. Finally, molecular dynamics simulations confirmed myricetin exhibited the lowest interaction energy, confirming hydroxyl-driven enhancement of hydrogen-bond and Van der Waals interactions. This work advances the understanding of hydroxyl-driven polyphenol interactions in whole potato flour systems.