Phase behavior of a binary mixture of rapeseed and soybean oils

The phase behavior of a mixture of rapeseed and soybean oils during cooling and heating was observed through differential scanning colorimetry (DSC). The mixture was cooled from 50 to −80 °C at 4 °C/min and heated from −80 to 50 °C at 2 °C/min. A polymorphic transition was observed during heating when the mixture contained soybean oil at a weight fraction of ≥ 0.7. Comparing the results presented herein with those for a binary mixture of high-purity triacylglycerols (TAGs) indicated that some peaks could be ascribed to the formation and melting of crystals rich in triolein and trilinolein. The total released or absorbed energies during cooling or heating were calculated from the DSC curves and were affected by the polymorphic transition and TAG interactions.