The mechanism of purple sweet potato anthocyanin extract to reduce the digestion rate and improve the starch digestion characteristics based on dough system

Current studies have predominantly focused on the in vitro interactions between starch and anthocyanins, neglecting the complexity of actual food composition systems. In this study, purple sweet potato anthocyanin extract (PSPAE)-dough mixture was constructed with the aim of refining the mechanism by which anthocyanins improved starch digestive properties. Animal experiments demonstrated that the dough containing PSPAE (250 mg/kg) significantly reduced peak blood glucose levels in mice by 39.69 %. Further analysis of the dough mixture properties-including texture, particle size, pasting characteristics, microstructure, infrared spectrum, and crystallinity-helped elucidate how PSPAE impedes starch digestion. The incorporation of 600 mg of PSPAE into the dough led to a 40.45 % reduction in the volume mean diameter compared to the blank dough. Textural and microstructural examinations suggested that PSPAE obstruct the interaction forces between starch molecules by filling gluten protein pores or wrapping starch molecules. This denser microstructure likely contributes to enhanced starch resistance. Additionally, alterations in dough crystallinity revealed that PSPAE encourages the reorganization of linear starch molecules, boosting the content of resistant starch and thereby reducing starch digestibility. This study enriches the mechanism of PSPAE in ameliorating diabetes symptoms and provides theoretical insights for the development of functional foods aimed at diabetes management.