Journal of Food Engineering, Vol.77, No.1, 126-134, 2006
Modeling temperature dependence of honey viscosity and of related supersaturated model carbohydrate systems
The viscosities of a unifloral honey and supersaturated sugar solutions were measured between -5 and 70 degrees C. All systems exhibited Newtonian behavior with reducing viscosity as increasing temperature. Four models (Arrhenius, VTF, WLF and Power Law) were investigated to describe the temperature dependence of viscosity. Among the different ways of using the WLF model, the method of reduced variables was the most suitable way to calculate coefficients. Oppositely, the WLF with "universal coefficients" badly predicted the temperature dependence of viscosity. When the calculated and experimental points were plotted as a function of (T-T-g), WLF (with coefficients calculated by the reduced variables method), VTF and power law models fitted the experimental data in a better trend than the Arrhenius equation. Also, the extrapolation of fitted curves into the glass transition region, showed that the Arrhenius model predicts the lowest viscosity values, while the WLF model (with coefficients calculated by the reduced model method) predicts the highest viscosity values in that region. VTF and Power Law models provided curves with intermediate solutions between Arrhenius and WLF model. (c) 2005 Elsevier Ltd. All rights reserved.