Specific contribution of lycopene to the antioxidant activity of the fat-soluble fraction of tomato products

摘要

The results are reported of experiments performed to evaluate lycopene specific contribution to the antioxidant activity of the tomato fat-soluble fraction. This contribution, expressed as TEAC, was found to be 3.40 mM/kg of dry matter and, on average, amounts to 81 percent of total TEAC of the fat-soluble fraction. The possibility was also evaluated of identifying in lycopene a quality marker for the shelf-life of commercial tomato products. Unlike other classical parameters such as sugar content,the formation of 2.5-hydroxymethyl-2-furfuraldehyde (HMF), Gardner colour and serum absorbance measurements, lycopene showed a total insensitivity to storage conditions and remains unaltered over time even under light exposure conditions (18 deg Brix tomato paste in glass jar about ten years old). Even on the one hand, lycopene could not be used as a quality marker, on the other hand the total stability of this precious antioxidant in tomato commercial products was confirmed even beyond their shelf-lif