Synthesis and properties of erucic acid triacylglycerols

The chemical synthesis of high-erucic acid triacylglycerols by a direct esterification approach was investigated in this study. A two-stage process was adopted in which reactants (without any catalyst) were heated at 160±5°C for 4 h, followed by heating at 250±10°C for 8 h. Purification of the esterified product was achieved by alkali refining, followed by alumina column chromatography. A greater than 85% yield of pure triacylglycerols was obtained, which contained 90% erucic acid, by using a 5% molar excess of erucic acid in the reaction. Oils containing erucic acid ranging from 45 to 91% were prepared by chemically interesterifying native high-erucic acid rapeseed (HEAR) oil and synthetic high-erucic arid triacylglycerols. The melting point, cloud point, pour point, titter and viscosity of all oils exhibited positive correlations with the erucic acid content, whereas saponification value, iodine value and refractive index showed negative correlations. Randomization of native HEAR oil resulted in an increase in the melting point, cloud point and pour point.