Assessing the influences of β-glucan on highland barley starch: Insights into gelatinization and molecular interactions

Developing highland barley products is complex, possibly due to the presence of β-glucan in highland barley. This study aims to investigate the impact of β-glucan on the physicochemical properties, microstructure, and molecular interactions of highland barley starch (HBS) during gelatinization and aging. Increasing the β-glucan content significantly reduced peak viscosity, setback viscosity, and breakdown viscosity, indicating altered gelatinization behavior. The β-glucan content increase caused a significant drop in peak viscosity. With 20% β-glucan addition, it reduced by 883 mPa·s, nearly 38%. Rheological analysis showed a transition from a solid-like to a liquid-like texture or quality, ultimately leading to a shear-thinning behavior. Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the interaction between HBS and β-glucan via intermolecular hydrogen bonding, promoting the formation of double helical structures in starch. These findings provide a deeper understanding of the role of β-glucan in the processing of highland barley, highlighting its influence on the starch's properties.