Kinetics of lycopene degradation in sunflower and grape seed oils
The stability of lycopene in two vegetable oils, sunflower seed oil (SSO) and grape seed oil (GSO), was investigated by analyzing the carotenoid degradation kinetics in the temperature range of 10–40°C. A tomato oleoresin containing 6% (w/w) of lycopene was used to prepare lycopene-enriched oil samples. Analysis of kinetic data showed that lycopene degradation follows first-order kinetics, with an apparent activation energy of 70.7 kJ mol–1 in SSO and 69 kJ mol–1 in GSO. The estimated half-life of lycopene was found to depend on oil type and storage temperature. At 20°C, it varied between 59 and 122 days, while at 4°C it was comprised between 302 and 650 days. At all temperatures, lycopene was more stable in SSO than in GSO, which is likely due to the higher content of antioxidant compounds in SSO.