|Chang, Tungsun - JOHN HOPKINS UNIVERSITY|
|Tseng, Yiider - JOHN HOPKINS UNIVERSITY|
|Wirtz, Denis - JOHN HOPKINS UNIVERSITY|
Submitted to: American Association of Cereal Chemists Meetings
Publication Type: Abstract Only
Publication Acceptance Date: September 18, 2006
Publication Date: September 18, 2006
Citation: Xu, J., Chang, T., Inglett, G.E., Kim, S., Tseng, Y., Wirtz, D. 2006. Micro-heterogeneity and micro-rheological properties of high-viscosity oat beta-glucan solutions [abstract]. American Association of Cereal Chemists Meetings. p. 91. Technical Abstract: Soluble fiber beta-glucan is one of the key dietary materials in the healthy food products known for reducing serum cholesterol levels. However, the physical properties of beta-glucan are rarely known. In this work, the micro-structural heterogeneity and micro-rheology of high-viscosity oat beta-glucan solutions were investigated using the technique of multiple-particle tracking (MPT). By monitoring the thermally driven displacements of well-dispersed micro-spheres via video fluorescence microscopy, the beads' displacement distributions are statistically analyzed. By comparing the distribution of the time-dependent mean-square displacement (MSD) and ensemble-averaged MSD of polystyrene micro-spheres imbedded in four concentrations of high-viscosity oat beta-glucan solutions, we found that the solutions exhibited perfectly homogeneous behavior at <1%, but the material showed a certain degree of heterogeneity at 2%. Micro-rheology investigation revealed that high-viscosity oat beta-glucan solutions displayed nearly perfect viscous behavior at <1%, but the property changed into viscoelastic one at 2%. Both micro-structural heterogeneity and micro-rheological property shifts occurred in a small concentration range, between 1% and 2% of high-viscosity oat beta-glucan.