High-pressure supercritical carbon dioxide extraction of Idesia polycarpa oil: Evaluation the influence of process parameters on the extraction yield and oil quality

High-pressure supercritical carbon dioxide extraction (HPSE) was used for extraction oil from Idesia polycarpa (I. polycarpa) at extraction pressure up to 65 MPa. A series of important process parameters were investigated by response surface methodology (RSM) to obtain high extraction yield. Under the optimum conditions, the highest extraction yield was 21.42 +/- 0.31 %. The quality of oil was evaluated in terms of extraction yield, nutritional ingredients such as gamma-tocopherol, DL-alpha-tocopherol, beta-sitosterol and squalene, fatty acids profile, antioxidant activity and physicochemical indices of oil and compared to the oil obtained by lower extraction pressures at 35 MPa and 50 MPa, respectively. The results proved that HPSE could increase the I. polycarpa oil extraction recovery and improve the quality of oil with higher nutritional ingredients content, lower acid value and better antioxidant activity. Furthermore, it could not change the fatty acids composition and have no harmful ingredients under the high extraction pressure.