Scientific Study

The purpose of investigation was to assess the effect of lycopene on the peroxide value, acid value, fatty acids, total phenolic content and ferric-reducing antioxidant power of walnut oil. Walnut oil was extracted from Xinjiang walnut variety using cold pressing method. Our study reported that after 45 days of accelerated oxidation at 60 °C (Schaal oven test), 0.005% lycopene exhibited the greatest antioxidant effect than other addition levels of lycopene. Therefore, under ambient storage conditions, the shelf-life of walnut oil could be extended up to 16 months by 0.005% lycopene. Moreover, 0.005% lycopene added to walnut oil had a significantly higher content of saturated fatty acid, unsaturated fatty acid, total phenol, reducing ability of the polar and non-polar components than the blank sample (walnut oil without any addition of lycopene). In conclusion, lycopene improved the quality of walnut oil because of its antioxidant effect against lipid oxidation.