Recent Advances in Barley Starch: Structural Insights, Functional Properties, Modification Strategies, and Food Applications: A Review

ABSTRACT

Barley starch is a functionally distinct cereal starch characterized by complex structural heterogeneity and intrinsic properties that strongly influence its physicochemical behavior and digestion kinetics. Compared with other conventional cereal starches, barley starch exhibits a broad genetic variation in amylose content, a characteristic bimodal granule size distribution, and amylopectin enriched in intermediate‐ to long‐chain branches. These hierarchical structural features interact across molecular, crystalline, and granular scales to influence starch organization and functionality, resulting in restricted granule swelling, enhanced gel elasticity, high paste stability, and a greater propensity for resistant starch (RS) formation. Although numerous studies have investigated individual aspects of barley starch structure and functionality, an integrated framework linking multiscale structural organization to physicochemical properties, processing behavior, and food applications remains limited. This review critically synthesizes recent advances (2020–2026) in the hierarchical structure–function relationships of barley starch, linking molecular fine structure, granular organization, physicochemical functionality, processing‐induced structural changes, and digestibility. Structural organization can be examined across hierarchical levels, from molecular fine structure to granule morphology, and systematically linked to its thermal, pasting, rheological, and digestibility characteristics. Advances in multiscale structural characterization have increasingly enabled structure‐guided modification of barley starch through physical, chemical, enzymatic, and biological approaches, offering greater control over its techno‐functional and nutritional properties. Leveraging these structural attributes enables optimized processing and nutritional functionality across diverse food applications, including low‐glycemic‐index products, gluten‐free formulations, plant‐based meat analogues, edible films, fermented foods, and 3D‐printed systems. Future research should prioritize an integrated multiscale structural analysis, sustainable modification strategies, and predictive structure–function modelling to achieve precise control of barley starch functionality within complex food matrices.