Synergistic modification of multi-frequency power ultrasound and rose polyphenols on physicochemical, structural and...

This study investigated the synergistic modification of high amylose corn starch (HACS) using multi-frequency power ultrasound (MFPU) combined with edible rose polyphenols (ERP). The structural modulation mechanisms and digestibility improvement effects were systematically examined. The results demonstrated that MFPU significantly enhanced the binding efficiency between ERP and HACS, with optimal binding observed at 40/60 kHz (dual-frequency) and 20/40/60 kHz (tri-frequency) in the sequential working modes. Notably, MFPU treatment markedly altered the starch digestibility profile. Under optimized conditions, the complexes exhibited a 19.05 % reduction in rapidly digestible starch (RDS) and 4.44 % decrease in slowly digestible starch (SDS), accompanied by a 23.49 % increase in resistant starch (RS) content. Structural characterization revealed that the MFPU-ERP treatment enhanced the double-helical content and short-range molecular order of HACS, leading to improved structural organization. Crucially, X-ray diffraction analysis confirmed a crystalline transformation from native B-type to a B + V-type polymorph, with the formation of stable V-type inclusion complexes contributing to enhanced enzymatic resistance. These findings collectively demonstrate that MFPU represents an effective physical modification technology for facilitating polyphenol-starch interactions and developing functional starch-based materials with improved nutritional properties.