Stability and degradation kinetics of lycopene in vegetable oils

The stability of lycopene in sunflower seed oil (SSO), grape seed oil (GSO) and rice bran oil (RBO) was investigated in the temperature range of 10-40 °C. Kinetic analysis of lycopene degradation showed that the process is first-order with respect to the carotenoid concentration, with apparent activation energies between 50.8 kJ mol-1 (RBO) and 70.0 kJ mol-1 (GSO). The half-life of lycopene in the oils was dependent on the storage temperature and varied from 303 to 530 days, at 4 °C, and from 86 to 104 days, at 20 °C. Below 15-20 °C, stability increased in the order: RBO < GSO < SSO, while at higher temperatures such differences tended to disappear. This is likely due to the combined effects of endogenous antioxidants and unsaturated triacylglycerols in the oils on the degradation pathway of lycopene. 2011 Praise Worthy Prize S.r.l. - All rights reserved