earticle

영어

Rheological properties of acorn flour-guar gum mixtures (4% w/w) at different guar gum concentrations (0, 0.2, 0.4, 0.6, and 0.8% w/w) were evaluated in steady and dynamic shear. The acorn flour-guar gum mixtures at 25℃ showed high shear-thinning flow behavior (n= 0.20-0.27). Consistency index (K), apparent viscosity (,100), and Casson yield stress (oc) increased with the increase in guar gum concentration. Within the temperature range of 25-70℃, the ,100$ of mixtures obeyed the Arrhenius relationship with high determination coefficient (R2 = 0.974-0.994). Activation energy values (5.37-6.77 kJ/mole) of acorn flour dispersions in the mixtures with guar gum (0.2-0.8%) were much lower than that (12.5 kJ/mole) of acorn flour dispersion (0% guar gum). Storage modulus (G'), loss modulus (G"), and complex viscosity () increased with the increase in guar gum concentration. Dynamic rheological data of 1n (G', G") versus ln frequency (w) of guar gum-acorn flour mixtures had positive slopes with G' greater than G" over most of the frequency range, indicating that they exhibited weak gel-like behavior.