Extraction of resveratrol from the pomace of Palomino fino grapes by supercritical carbon dioxide

Resveratrol is a phenolic compound that is present in grapes and has significant benefits for human health. The development of methods to obtain concentrates of this compound is currently a major challenge in the food industry. In the work described here, resveratrol from grape seeds, stems, skin and pomace of the Palomino fino grape variety was extracted by supercritical carbon dioxide extraction. The effect of pressure (100, 400 bar), temperature (35, 55 degrees C) and the addition of modifier (5% v/v of ethanol) was evaluated to identify optimal resveratrol extraction from this by-product. Extraction yields and concentrations of resveratrol in the extracts were determined. The best results were obtained on working at high pressure and low temperature using 5% v/v ethanol as a co-solvent. (C) 2009 Elsevier Ltd. All rights reserved.