Agro-industrial tomato by-products and extraction of functional food ingredients

Agro-industrial by-products are important sources of functional food ingredients with commercial interest to decrease the volume of by-products and also to improve the economic viability of processes, by producing added value ingredients. For this purpose, application of the supercritical carbon dioxide (SC-CO2) technology to add value to tomato (cultivar 'Admiro' F1) by-products (peel, seeds and small amount of pulp) was tested. Optimisation of extraction parameters of high value-added ingredients (oleoresin with 60% cis-lycopene isomers concentration) was carried out and antioxidant effect of extract in cell culture was analysed. The extract obtained at optimised conditions (52 degrees C temperature, a 55 MPa pressure and a 180 min extraction time), was characterized for total lycopene and lycopene different isomers (15-cis-lycopene, 13-cis-lycopene, 9-cis-lycopene, 7-cis-lycopene, trans-lycopene and 5-cis-lycopene) and the antioxidant effect of extracts was evaluated by assessing the production of the reactive oxygen species (ROS) by murine macrophage J774 cell culture. Results showed that the SC-CO2 extracts of tomato by-products (peel, seeds and small amount of pulp) is a potential source of cis-lycopene isomers (the total content of cis-lycopene isomers in the SC-CO2 extract was 60%) oleoresin with promising applications in food and pharmaceutical industries.