Optimization of supercritical fluid extraction of lycopene from tomato skin with central composite rotatable design model

Response surface methodology using the central composite rotatetable design (CCRD) model was used to optimize parameters for supercritical carbon dioxide extraction of lycopene (C40H56) from dried tomato skin. The CCRD consisting of three-factored factorial design with two levels was used in this study. The factors used were temperature of the extraction chamber (40 and 70 °C), pressure of the extraction fluid (25 and 45 MPa), and modifier concentration (5 and 15%). Judged by the lack-of-fit-test, coefficient of determination and the standard errors results from the analysis of variance have shown the model to be adequate. The linear, quadratic and cross-effects were 0.58, 0.28 and 0.05, respectively. The independent variables have significantly (p < 0.05) influenced the extraction of all trans-lycopene from tomato skin. Although, no significant (p > 0.05) individual effect of modifier concentration shown, a synergetic effect was observed. A second-degree polynomial equation was developed from a response surface analysis for all trans-lycopene yield and the highest yield was predicted at 62 °C, 45 MPa (450 bar) and 14% temperature, pressure and modifier concentration, respectively and the recovery of all trans-lycopene was 33%.