title: Green extraction of antioxidants from different varieties of red grape pomace.
abstract: The extraction yield, phenolic content, anthocyanin content and antioxidant activity of extracts from different varieties of red grapes, Cabernet Sauvignon, Merlot, Petit Verdot, Syrah, Tempranillo and Tintilla, using pressurized green solvents have been analyzed. Two techniques were studied and compared: supercritical fluid extraction (SFE) with CO2 + 20% ethanol and pressurized liquid extraction (PLE) with either ethanol, water or an ethanol/water mixture as the extraction solvents. The Petit Verdot variety allowed the highest global and phenolic yield, and antioxidant activity. The best conditios for PLE obtained from the experimental design and kinetic study were 50% ethanol/water as the pressurized solvent at 90 bar, 120 °C, a flow rate of 5 g/min and, an extraction time of 90 min. A statistical analysis of variance has been performed and it was found that temperature is the only variable that has a statistical influence on the extraction yield. The antioxidant activity levels of the extracts are very promising and they are similar to those obtained with the antioxidant tocopherol.
authors.affiliation: Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cadiz, International Agri-food Campus of Excellence, ceiA3, Box 40, 11510 Puerto Real, Cadiz, Spain. mariajose.otero@uca.es.
authors.forename: María José
authors.initials: MJ
authors.lastname: Otero-Pareja
authors.affiliation: Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cadiz, International Agri-food Campus of Excellence, ceiA3, Box 40, 11510 Puerto Real, Cadiz, Spain. lourdes.casas@uca.es.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Casas
authors.affiliation: Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cadiz, International Agri-food Campus of Excellence, ceiA3, Box 40, 11510 Puerto Real, Cadiz, Spain. teresafernandez.ponce@uca.es.
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Fernández-Ponce
authors.affiliation: Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cadiz, International Agri-food Campus of Excellence, ceiA3, Box 40, 11510 Puerto Real, Cadiz, Spain. casimiro.mantell@uca.es.
authors.forename: Casimiro
authors.initials: C
authors.lastname: Mantell
authors.affiliation: Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cadiz, International Agri-food Campus of Excellence, ceiA3, Box 40, 11510 Puerto Real, Cadiz, Spain. enrique.martinezdelaossa@uca.es.
authors.forename: Enrique J
authors.initials: EJ
authors.lastname: Martínez de la Ossa
mesh_terms: D000872:Anthocyanins / Q000737:chemistry / Q000302:isolation & purification*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors; D025924:Chromatography, Supercritical Fluid; D000431:Ethanol; D005638:Fruit / Q000737:chemistry*; D055772:Green Chemistry Technology; D059625:Liquid-Liquid Extraction; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification*; D010851:Picrates / Q000037:antagonists & inhibitors; D010936:Plant Extracts / Q000737:chemistry*; D011312:Pressure; D012997:Solvents; D013696:Temperature; D027843:Vitis / Q000737:chemistry* / Q000145:classification; D014867:Water
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D001713:Biphenyl Compounds; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D012997:Solvents; D014867:Water; D000431:Ethanol; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: anthocyanins; antioxidant activity; grape pomace; high pressure extraction; phenolic compounds; pressurized liquid extraction