Rheological characterization of vegetable oil blends: Effect of shear rate, temperature, and short‐term heating

Abstract

AbstractRheological characterization of canola–olive and canola–sesame blends was carried out. The canola–olive and canola–sesame blends were prepared in the vol/vol ratios of 90:10, 70:30, and 50:50. The rheology was studied at shear rates 1–132 s−1 and temperatures 15–65°C (288.15–338.15 K) before and after heating for 5, 10, and 15 min. Viscosity varied linearly with percentage composition of blend. Power law, Sisko, Cross, and Carreau equations for viscosity‐shear relation, and Arrhenius and Williams–Landel–Ferry (WLF) equations for viscosity‐temperature relation were evaluated. The reduced χ2 values for the 70:30 canola–olive blend at 25°C were 7.84 × 10−5, 2.28 × 10−5, 1.26 × 10−6, and 1.23 × 10−6 for Power law, Sisko, Cross, and Carreau equations, respectively. Best fits were produced by Cross and Carreau for viscosity‐shear relation and by WLF equation for viscosity‐temperature relation. Short‐term heating was had no significant effect on the rheological profiles of the pure oils and their blends.Practical ApplicationsRheological characterization of vegetable oil blends could be helpful to engineers and scientists in formulation of vegetable oil blends for edible purposes and in designing the required process equipment. Curve fitting studies in rheology are especially helpful because the fitted equations can be used to solve complex flow problems encountered in engineering. The study could also be of interest to researchers and formulators in the field of biolubricants as well as medicinal oil formulations.