PROCESS OF EXTRACTION OF CAROTENOIDS FROM CO2 UNDER LIQUID-VAPOR EQUILIBRIUM CONDITIONS

In this study, the extractability of lycopene and β-carotene from tomato skin and pulp using as solvent the liquid CO2 under its liquid-vapor equilibrium conditions was studied. The temperature effect (281K and 299K, corresponding to CO2 equilibrium pressures of 54 bar and 64 bar respectively) and the use of non-toxic modifiers (ethanol, olive oil) in the lycopene and β-carotene content of the liquid CO2 extracts from tomato skin and pulp are observed. The liquid CO2 extraction of tomato pulp at 299K yielded a higher content of β-carotene (18.2 µg/g tomato) than at 281 K. The best results regarding the amount of lycopene were obtained at a temperature of 299K in presence of olive oil (6.84 μg/g tomato) whereas the optimal extraction process parameters of β-carotene are at 299K temperature and 64 bar in presence of ethanol (19.8 μg/g tomato). The addition of 2% ethanol as CO2 co-solvent at 299 K increased the amount of lycopene and β-carotene extracted from tomato skin and pulp whereas the addition of 2% olive oil at 299 K increased slightly the extracted amounts of lycopene but decreased drastically the extracted β-carotene from both tomato skin and pulp.