Extraction and modeling of flaxseed (Linnum usitatissimum) oil using subcritical propane

This study aimed at investigating flaxseed (Linnum usitatissimum) oil extraction using subcritical propane. Extractions were performed in a laboratory scale unit at temperature (20-60 °C) and pressure (80-120 bar) experimental conditions. Subcritical extraction process kinetic aspects evaluation was performed using four mathematical models found in the literature. The subcritical propane process successfully extracted Omega 3-6-9 fatty acids presenting good yielding in the experimental conditions studied. Physical characterization for commercial and subcritical propane extraction oils presented 1.477 and 1.473 refractive indexes at 40 °C, respectively. The oil extracted using subcritical propane presented free fatty acid contents lower than commercial oil (0.95% wt vs 1.37% wt). The adjusted parameters models presented good fitting with the experimental data under the investigated conditions.