Rheology of selected Polish honeys

The rheological properties of seven varieties of Polish honeys, among them five nectar varieties (acacia, buckwheat, linden, multifloral and rape), a nectar-honeydew and a honeydew variety, were investigated over a temperature range of 10–40 °C. The honeys had a water content of 14.7–18.0 g/100 g. The viscosity curves of the samples were obtained using a rotational rheometer. All the honeys exhibited Newtonian behaviour. Their viscosity varied between 1.76 and 252.6 Pa s according to the kind of honey and the temperature of measurement. The temperature dependence of viscosity was described using the Arrhenius equation and the Williams–Landel–Ferry (WLF) equation. The values of flow activation energy varied between 92.34 and 105.25 kJ/mol, those of glass viscosity (ηG) ranged from 1.88 × 1011 to 2.86 × 1011, and the values of glass transition temperature (TG) were of 220.34–228.39 K.