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.
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机译：分析了使用加压绿色溶剂对红葡萄，赤霞珠，梅洛，小维多，西拉，坦普拉尼洛和丁子菊等不同品种的葡萄提取物的提取率，酚含量，花色苷含量和抗氧化活性。研究和比较了两种技术：使用CO2 + 20％乙醇的超临界流体萃取（SFE）和使用乙醇，水或乙醇/水混合物作为萃取溶剂的加压液体萃取（PLE）。 Petit Verdot品种具有最高的总酚产量和抗氧化活性。通过实验设计和动力学研究获得的PLE的最佳条件是在90 bar，120°C，5 g / min的流速和90 min的萃取时间下使用50％乙醇/水作为加压溶剂。已经进行了方差的统计分析，并且发现温度是唯一对提取产率具有统计影响的变量。提取物的抗氧化剂活性水平非常有前途，与使用抗氧化剂生育酚获得的水平相似。
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