Supercritical Fluid Extraction of Lycopene from Tomato Processing Byproducts

Tomato seeds and skins acquired from the byproduct of a local tomato processing facility were studied for supercritical fluid extraction (SFE) of phytochemicals. The extracts were analyzed for lycopene, β-carotene, α-carotene, α-tocopherol, γ-tocopherol, and δ-tocopherol content using high-performance liquid chromatography−electrochemical detection and compared to a chemically extracted control. SFEs were carried out using CO2 at seven temperatures (32−86 °C) and six pressures (13.78−48.26 MPa). The effect of CO2 flow rate and volume also was investigated. The results indicated that the percentage of lycopene extracted increased with elevated temperature and pressure until a maximum recovery of 38.8% was reached at 86 °C and 34.47 MPa, after which the amount of lycopene extracted decreased. Conditions for the optimum extraction of lycopene from 3 g of raw material were determined to be 86 °C, 34.47 MPa, and 500 mL of CO2 at a flow rate of 2.5 mL/min. These conditions resulted in the extraction of 61.0% of the lycopene (7.19 μg lycopene/g). Keywords: Lycopene; supercritical fluid extraction; carotenoids; tocopherols; chromatography