Résumé
The aim of the study was to evaluate the degradation kinetics of carotenoids (CTs) in vacuum-fried papaya (Carica papaya L.) chips (PCs) during storage at four temperatures (15, 25, 35 and 45 °C) for 52 and 94 days for the two highest and lowest temperatures, respectively. Three treatments were applied to obtain the chips: chips with soy oil (24% lipids) and chips with palm oil (24% and 29% lipids). All the chips were packaged under air or nitrogen conditions. The CTs analyzed by HPLC-DAD were per order of content all-E-lycopene (LYC), Z-lycopene (Z-LYC), all-E-β-carotene (BC), all-E-β-cryptoxanthin (BCX) and Z-β-carotene (Z-BC). The all-E-forms represented 80% of carotenoids in PCs. No significant carotenoid degradation was observed in the PCs packaged under nitrogen conditions during storage. For chips stored under air conditions, a second-order kinetic model best fitted the experimental data. Rate constants for LYC degradation were the lowest, while BCX and BC presented similar rate constants 4–23-fold higher depending on lipid composition. All Z-isomers degraded faster than all-E-forms, but Z-BC degraded only 2–4-fold faster than Z-LYC. All CTs followed Arrhenius temperaturedependency pattern and LYC showed the lowest activation energies (5–21 kJ/mol). A higher lipid content in the chips with palm oil enhanced the carotenoid retention in PCs. Moreover, a greater retention (p < 0.05) of CTs was observed in PCs with soy oil. The use of soy oil instead of palm oil increased the theoretical half-life (at 25 °C) by 2.2, 1.3 and 5.9-fold for BCX, BC and LYC, respectively. Packaging under nitrogen conditions and lipid composition may be considered to optimize the shelf life and carotenoid retention in PCs during storage.