Supercritical fluid extraction of fig leaf gourd seeds oil: Fatty acids composition and extraction kinetics

Fig leaf gourd (Cucurbita ficifolia, Bouché) seeds oil was extracted in a Soxhlet apparatus (oil content of 43.5%) and by supercritical fluid extraction (SFE) in the temperature and pressure ranges of 308–318 K and 18–20 MPa, respectively.Both oil batches showed similar fatty acids compositions. Main fatty acids were ω6-linoleic acid (about 60%), palmitic acid (about 15%) and oleic acid (about 14%). The induction time was used to determine the oxidative stability, 4.2 and 8.3 h being obtained for SFE extracted oil and n-hexane extracted oil, respectively.Regarding the kinetics of supercritical fluid extraction, the Sovová’s model was selected and successfully applied to the description of the oil extraction curves. The fitted parameters, the overall mass transfer coefficient for the fluid phase, Kf, and the overall mass transfer coefficient for the solid phase, Ks, vary in the ranges 2.34–4.57 × 10−2 s−1 and 1.73–4.34 × 10−4 s−1, respectively. The free oil content for milled seeds, fk, was calculated as 61%. These parameters are consistent with those published for several other oils.

Graphical abstractFig leaf gourd seeds oil was extracted (oil content, 43.5%) by supercritical fluid extraction (SFE) in temperatures 308–318 K and pressures 18–20 MPa. Main fatty acids were linoleic (∼60%), palmitic (∼15%) and oleic (∼14%). The induction time was used to determine the oxidative stability, 4.2 and 8.3 h being obtained for SFE extracted oil and n-hexane extracted oil, respectively.The Sovová’s model was successfully applied. The fitted parameters, overall mass transfer coefficient for the fluid phase, Kf, and overall mass transfer coefficient for the solid phase, Ks, vary in 2.34–4.57 × 10−2 s−1 and 1.73–4.34 × 10−4 s−1. The free oil content for milled seeds, fk, was 61%.Figure optionsDownload full-size imageDownload as PowerPoint slide