Mechanistic review of binary to ternary starch-biomolecule assemblies: Integrated insights into resistant starch formation and structure-function relationships.

This review establishes a progressive analytical framework for starch-biomolecule interactions ranging from binary to ternary systems, focusing on the formation mechanisms of resistant starch (RS) and the relationship between its structure and function. Starch-protein, starch-lipid, starch-polyphenol, and starch-non-starch polysaccharide (NPS) interactions lead to digestion resistance primarily through single dominant mechanisms such as physical barriers, molecular ordering, or enzyme inhibition. Starch-lipid-protein, starch-non-starch polysaccharide-protein, and starch-polyphenol-protein assemblies enhance molecular ordering via cross-linked protein networks and prolong enzyme inhibition through the sustained release of proteolytic peptides. Meanwhile, starch-lipid-polyphenol assemblies achieve synergistic resistance through ligand-complementary V-type ordering and slow release of polyphenols. Based on this mechanistic framework, this review further summarizes its potential applications in postprandial blood glucose control, gut microbiota regulation, and the field of rheology for dysphagia. Structure-function-based design strategies for RS are proposed for type 2 diabetes, obesity, dysphagia and endurance athletes, whilst challenges such as the immaturity of quantitative structure-function modelling are discussed and addressed. It is hoped that this will provide a systematic mechanistic basis for the rational design of ternary RS and open up new avenues for the development of structure-directed functional starches.