A. Molero Gómez

Recovery of grape seed oil by liquid and supercritical carbon dioxide extraction: a comparison with conventional solvent extraction

Abstract In this work the extraction of grape seed oil by means of liquid and supercritical carbon dioxide as solvent is described. The operating conditions to determine the maximum extraction yield were studied. The efficiency of supercritical fluid extraction (SFE) was similar to that obtained by conventional liquid extraction, but the quality of the supercritically extracted oil was higher, equivalent to a degummed, liquid- extracted oil. It is considered that SFE is competitive with conventional liquid extraction, because the solvent distillation and oil refining stages can be omitted.

Characterisation and Process Development of Supercritical Fluid Extraction of Soybean Oil

This work describes and analyses the extraction of soybean oil using supercritical carbon dioxide as a solvent from the point of view of both operative method and pre-treatment of the raw material. The best conditions for soybean oil extraction were obtained at a pressure of 300 bar, a temperature of 40 C and a solvent flow rate of 1.8 L/min at STP. The yields obtained using the supercritical fluid under the best operating conditions were similar to those obtained by conventional extraction methods using hexane as the solvent (19.9%w/w.); furthermore, the quality of oil extracted by the supercritical fluid was higher (acidity, 0.8). The fatty acid composition of the soybean seed oil extracted by supercritical fluid was particularly rich in unsaturated fatty acids, particularly linoleic acid (51.8%). For these reasons, the soybean seed oil extracted using supercritical carbon dioxide could compete with that obtained by the conventional process, since the oil refinement stages are simplified significantly and the solvent distillation stage is completely removed, which are the two most costly processing stages in terms of energy consumption.This work describes and analyses the extraction of soybean oil using supercritical carbon dioxide as a solvent from the point of view of both operative method and pre-treatment of the raw material. The best conditions for soybean oil extraction were obtained at a pressure of 300 bar, a temperature of 40 � C and a solvent flow rate of 1.8 L/min at STP. The yields obtained using the supercritical fluid under the best operating conditions were similar to those obtained byconventional extraction methods using hexane as the solvent (19.9 %w/w.); furthermore, the qualityof oil extracted bythe supercritical fluid was higher (acidity, 0.8). The fatty acid composition of the soybean seed oil extracted by supercritical fluid was particularlyrich in unsaturated fattyacids, particularlylinoleic acid (51.8%). For these reasons, the soy bean seed oil extracted using supercritical carbon dioxide could compete with that obtained bythe conventional process, since the oil refinement stages are simplified significantlyand the solvent distillation stage is completelyremoved, which are the two most costlyprocessing stages in terms of energyconsumption.

Caracterización del aceite de semilla de borraja extraído con dióxido de carbono supercrítico

The present work is based on a comparative study of the borage seeds oil obtained with supercritical carbon dioxide by means of the conventional extraction using hexane as a solvent. In the optimal working conditions, the results obtained in the extraction with carbon dioxide are comparable to those obtained in the extraction with hexane, although the oils quality is higher. Therefore, the process of supercritical extraction with carbon dioxide could be more effective than conventional extraction because the solvent removal is not necessary and several steps of the oil refining process can be reduced notably.