Alternative oil extraction methods from Echium plantagineum L. seeds using advanced techniques and green solvents

Abstract

The edible oil processing industry involves large losses of organic solvent into the atmosphere and long ex-traction times. In this work, fast and environmentally friendly alternatives for the production of echium oil usinggreen solvents are proposed. Advanced extraction techniques such as Pressurized Liquid Extraction (PLE),Microwave Assisted Extraction (MAE) and Ultrasound Assisted Extraction (UAE) were evaluated to efficientlyextract omega-3 rich oil fromEchium plantagineumseeds. Extractions were performed with ethyl acetate, ethanol,water and ethanol:water to develop a hexane-free processing method. Optimal PLE conditions with ethanol at150 °C during 10 min produced a very similar oil yield (31.2%) to Soxhlet using hexane for 8 h (31.3%). UAEoptimized method with ethanol at mild conditions (55 °C) produced a high oil yield (29.1%). Consequently,advanced extraction techniques showed good lipid yields and furthermore, the produced echium oil had thesame omega-3 fatty acid composition than traditionally extracted oil.