Relationship between physicochemical properties and molecular structure of barley starch with different size distributions

Barley is primarily used in animal feed and malt production, and the structure-property relationship of barley starch (BS) remains understudied. This study examined the physicochemical and structural properties of BS from 25 genotypes and explored the structure-property relationship in the model system. For the first time, the structures and properties of BSs of unimodal and bimodal size distributions were systematically compared. Key factors such as amylose content, granule size, and the weight-based ratio of short to long chains of amylopectin (APS:APL) affected the BS functionality. Strong correlations were observed between thermal, rheological, pasting and granular size properties. Compared to maize and potato starches, BS had lower gelatinization temperatures, swelling power, and water solubility but higher amylose content, elasticity, and gel strength. These comparisons and structure-property relationship provide valuable insights to optimize the BS applications in the food and other industry.