Gas chromatographic determination of synthetic antioxidants in liquid frying oil samples

Natural and synthetic antioxidants play a significant role in retarding the lipid oxidation           reactions in food products. Prevention of lipid peroxidation has long become an important            issue, since oils and fats, essential to our diets, tend to encounter problems of oxidation and rancidity, which affect food quality and also may threat human health. A gas chromatography system equipped by CP sil 8 CB capillary column (50m×0.53mm i.d×1.5µm film thickness) was used to determine the antioxidants tert-butyl-hydroquinone, tert-butylhydroxyanisole, and 3,5-di-tert-butylhydroxytoluene simultaneously in Iranian commercial liquid frying oils. The recoveries of BHA, BHT and TBHQ were 95.44-105.04, 96.03-105.47 and 95.62–108.89%, respectively. 53 commercial liquid frying oils were analysed using the chromatographic method. The contents of BHA, BHT and TBHQ were found to be 0.00, 0.00 and 40.18±0.21 ‎mg.kg-1 respectively.The levels of synthetic antioxidants in studied samples were all below the legal limits of Iran (200 ‎mg.kg-1).