Apparent solubility of lycopene and β-carotene in supercritical CO2, CO2 + ethanol and CO2 + canola oil using dynamic extraction of tomatoes

Lycopene and beta-carotene were extracted from freeze-dried tomatoes (skin + pulp) with pure SC CO2 and SC CO2 + 5% w/w co-solvent at 40 degrees C, 400 bar and flow rates of 0.5 and 1.2 L/min. The apparent solubility of lycopene and beta-carotene in the multicomponent complex system was determined from dynamic extraction experiments using a laboratory-scale supercritical extraction system. Solubility of pure lycopene and beta-carotene in SC CO2 (binary system) was reported in the literature to be of the order of 10(-6) mole fraction. The apparent solubility of lycopene extracted from tomatoes with SC CO2 (multicomponent complex system) under the same conditions was almost one order of magnitude smaller. The apparent solubility obtained using oil as a co-solvent was higher than that obtained with ethanol as a co-solvent or pure SC CO2. The differences in solubility are mainly due to the polarity of the co-solvent and the impact of the tomato matrix in the multicomponent complex system. (C) 2010 Elsevier Ltd. All rights reserved.