Quality Parameters, Empirical and Kinetic Models of Lycopene and Beta-carotene Bioformation in Tomatoes (Solanum lycopersicum)

This study examines a kinetic model estimating the geranyl geranyl pyrophosphate (GGPP) concentration in the carotenoid pathway in tomatoes (Solanum lycopersicun). Kinetics of bioformation of carotenoids in tomatoes of different cultivars (Cherry-Nasmata, VAR-10, and 4-lobes) at different ripening stages and conditions was used to evaluate the GGPP concentration in the kinetic model. Physicochemical parameters, lycopene and beta-carotene contents were assessed and compared under the two ripening conditions using standard laboratory procedures. The solid contents in the three cultivars of tomato were in the range of 5.61% to 6.85% and 5.83% to 7.16% at field and ambient temperature ripening, respectively; the pH values were all in the acidic region. Highest lycopene and beta-carotene concentrations were observed in 4-lobes cultivar at field ripening. The obtained data from the empirical and kinetic modeling showed the exponential models as first-order kinetics for both lycopene and beta-carotene bioformation in Cherry-Nasmata and 4-lobes cultivars. This suggests that beta-carotene bioformation depends on the pathway of lycopene in the tomato cultivars. The quality parameters of the tomato cultivars showed that ripening conditions influenced the quality of tomato contents. Also the GGPP concentrations of some of the tomatoes were successfully estimated using the kinetic model.