Microrheological investigation of low-viscosity barley ß-glucan solutions by diffusion wave spectroscopy (DWS)

Authors: Xu, Jingyuan - James; Boddu, Veera; Liu, Sean

Submitted to: American Journal of Food Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/12/2022
Publication Date: 1/10/2023
Citation: Xu, J., Boddu, V.M., Liu, S.X. 2023. Microrheological investigation of low-viscosity barley ß-glucan solutions by diffusion wave spectroscopy (DWS). American Journal of Food Technology. 18(1), 8-15. https://doi.org/10.3923/ajft.2023.8.15.
DOI: https://doi.org/10.3923/ajft.2023.8.15

Interpretive Summary: Heart disease is the leading cause of death in the United States. Many scientific research reports suggest that reducing total and LDL cholesterol concentrations can decrease the risk of heart attack. Soluble fiber ß-glucan is one of the key dietary materials in healthy food products known for reducing serum cholesterol levels. Many new food products containing high amounts of ß-glucan have been invented and much research has been done on ß-glucan. However, the properties and the structure-function relationship of ß-glucan are still not clearly understood. This paper examines some of the physical properties of low-viscosity barley ß-glucan. Using a technology named Diffusion Wave Spectroscopy (DWS), we studied the flow behavior and micro-rheology of low-viscosity barley ß-glucan solutions. The results of this research give us much more insight into the physical properties of low-viscosity barley ß-glucan. It is also shown that the technique of DWS is powerful for studying the properties of food systems.

Technical Abstract: The microrheology of low-viscosity barley ß-glucan solutions was investigated by diffusion wave spectroscopy (DWS) technology. Mean-square displacement (MSD) of the microspheres imbedded at five concentrations of barley ß-glucan aqueous solutions were compared. The solutions exhibited nearly homogeneous behavior at less than or equal to 0.1% (wt.%) with very little heterogeneity, but the material displayed heterogeneity at concentrations above or equal to 0.5% (wt.%). The investigation also revealed that low-viscosity barley ß-glucan solutions showed nearly perfect viscous behavior at less than or equal to 0.1% (wt.%), but the property shifted into viscoelastic behavior at greater than or equal to 0.5% (wt.%). The magnitude of high-frequency viscoelastic moduli for the 0.5% - 1.5% (wt.%) low-viscosity barley ß-glucan solutions is proportional to the 3/4 power law of frequency, which is the semi-flexible polymer behavior. The identified properties of the low-viscosity barley ß-glucan solutions provided us new insights into ß-glucan behavior.