in this study, the efficacy of thyme (thymus vulgaris l.), sage (salvia officinalis l.), rosemary (rosmarinus officinalis l.) and bay (laurus nobilis) essential oils in stabilizing canola oil and its purified triacylglycerols (tags) during accelerated storage was investigated. -carotene bleaching test, 2,2'-diphenyl-1-picrylhydrazyl (dpph) radical scavenging test and conjugated diene tests indicated the antioxidant activity of thyme to be comparable with that of synthetic antioxidants. in oven test, thyme was most effective in decreasing the conjugated diene (cd) content, peroxide value (pv) and the p-anisidine value (av) of canola oil, being followed by rosemary and sage. the lowest specific extinction (k232 and k270) values during oxidation of essential oils supplemented tags were also obtained for thyme. the induction periods of canola oil increased slightly with essential oils. protection factors were in the range of 1.10-1.19 at 110^0c, while the protection factors were high (1.01-4.08) in triacylglycerols at 80^0c. based on the results, thyme was found to be suitable for the stabilization of vegetable oils.