Supercritical CO2 extraction of β-carotene and lycopene from tomato paste waste

Lycopene and beta -carotene were extracted from tomato paste waste using supercritical carbon dioxide (SC-CO2). To optimize supercritical fluid extraction (SFE) results for the isolation of lycopene and beta -carotene, a factorial designed experiment was conducted. The factors assessed were the temperature of the extractor (35, 45, 55, and 65 degreesC), the pressure of the extraction fluid (200, 250, and 300 bar), addition of cosolvent (5, 10, and 15% ethanol), extraction time (1, 2, and 3 h), and CO2 flow rate (2, 4, and 8 kg/h). The total amounts of lycopene and beta -carotene in the tomato paste waste, extracts, and residues were determined by HPLC. A maximum of 53.93% of lycopene was extracted by SC-CO2 in 2 h (CO2 now rate = 4 kg/h) at 55 degreesC and 300 bar, with the addition of 5% ethanol as a cosolvent. Half of the initially present beta -carotene was extracted in 2 h (flow rate = 4 kg/h), at 65 degreesC and 300 bar, also with the addition of 5% ethanol.