SC-CO₂ extraction of lycopene from red papaya using rice bran oil as a co-solvent lessens its degradation during storage

Lycopene was extracted from freeze-dried papaya using supercritical carbon dioxide and rice bran oil (RBO) as a co-solvent. Central composite design (Response surface methodology) with five levels of each process variable, i.e. pressure (25–50 MPa), temperature (55–85°C), and extraction time (60–210 min), was used for conducting the experiments. The single optimal point for various response variables was realized at 35.4 MPa, 67°C, and 130 min. Under these conditions, a lycopene extraction efficiency of 79.27 ± 1.69% and a γ-oryzanol content of 11,079 ± 146 mg/L were predicted. The combination of extraction temperature and time beyond 80°C and 180 minutes showed a detrimental effect on lycopene. Furthermore, the storage of extract under no-light conditions showed first-order degradation kinetics with half-life values of lycopene of 42, 24, and 9 days at 3, 10, and 25°C, respectively. Results show that the use of RBO as a co-solvent improved the extraction efficiency and prevented lycopene degradation during extraction and storage.