Rheology study of supercritically extracted tea-oil

Abstract

The rheological analysis on dynamic shear rate-viscosity relationship of tea-oil extracted from tea-oil tree seeds by supercritical extraction method was carried out at gradient temperatures and constant shear rate, respectively. The results show that at 20, 40, 60 and 80°C, once the shear rate increases gradually, the torque enlarges correspondingly, while the viscosity shows little difference. However, at the constant shear rate, the rising temperature results in a steady downtrend on tea-oil viscosity. This results reveal that tea-oil viscosity is not closely correlated with shear rate at constant temperature, yet negatively correlated with temperature at constant shear rate.

Keywords

tea-oil / rheology / dynamic shear rate / viscosity / supercritical extraction