Composition, physicochemical property and stability of canola seed oil: Impact of different pretreatment

This study aimed to investigate the effects of roasting, microwave, ultrasound and enzymolysis pretreatments on the composition, physicochemical properties, lipid oxidation and antioxidant activities of canola seed oils (CSOs). The results showed that all the pretreatments significantly increased the contents of total phenolic compounds, alpha-tocopherol, gamma-tocopherol and polyunsaturated fatty acids in CSOs relative to control. Moreover, the peroxide value, acid value, saponification value and iodine value of CSOs were improved by different pre- treatments. The oils extracted from the pretreated canola seeds exhibited the stronger DPPH and ABTS radicals scavenging activities than control, with the DPPH and ABTS radical scavenging rates up to 90% respectively at the concentration of 80 mg/L and 40 mg/mL. Furthermore, the pretreated CSOs possessed the excellent beta-carotene bleaching inhibitory abilities, and could inhibit the lipid oxidation during storage. Among four kinds of pretreatments, microwave and enzymolysis presented the better impacts on nutritional and functional properties of CSOs. This study demonstrated that the pretreatment prior to extraction could improve the nutritional values of canola seed oil and prolong its shelf life.