Rheological Properties and Processing Applicability of Physically and Enzymatically Modified Non-Waxy Barley Flour

This study analyzed the rheological properties of barley flour obtained from two non-waxy barley cultivars (Sogang and Huknuri) subjected to heat-moisture treatment (HM), enzymatic treatment (EZ), and combined treatment (HM-EZ), and evaluated the changes in texture and processing applicability according to modification methods.The transparency of non-waxy barley flour suspensions treated with HM and HM-EZ remained low during storage, suggesting the formation of dense gel structures.Texture analysis showed that HM and HM-EZ decreased the hardness, stress, and gel strength in the Sogang cultivar, whereas Huknuri tended to maintain higher structural stability.In steady shear flow analysis, all samples exhibited shear-thinning behavior with decreasing viscosity as the shear rate increased, and the HM and HM-EZ-treated flours showed higher shear resistance and viscosity stability.Dynamic rheological analysis showed that the storage modulus (G) was higher than the loss modulus (G) in all samples, indicating weak gel characteristics, and HM and HM-EZ maintained higher viscoelasticity and strengthened gel networks.In contrast, EZ had a moderate effect on the flow behavior because of partial starch chain degradation.Unlike previous studies focusing on single modification methods or limited rheological parameters, this study comparatively evaluated the combined effects of physical and enzymatic modifications on non-waxy barley flour.The results show that targeted modification strategies can effectively tailor the flow behavior and viscoelastic properties for starch-based food processing applications.Nevertheless, the limited number of cultivars and the laboratory-scale nature of the rheological evaluation highlight the need for further studies under practical processing conditions.