TY - JOUR T1 - Effect of Ethanol on Grape Seed Proanthocyanidin Extraction JF - American Journal of Enology and Viticulture JO - Am. J. Enol. Vitic. DO - 10.5344/ajev.2011.11053 SP - ajev.2011.11053 AU - Alberto Hernández-Jiménez AU - James A. Kennedy AU - Ana B. Bautista-Ortín AU - Encarna Gómez-Plaza Y1 - 2011/10/12 UR - http://www.ajevonline.org/content/early/2011/10/11/ajev.2011.11053.abstract N2 - Proanthocyanidins are found in the seeds and skins of wine grapes, and are extracted into the must-wine during maceration. In the case of seed proanthocyanidins, extraction is generally thought to be possible only in the presence of ethanol. This study examined the extraction of seed proanthocyanidins in model solutions with increasing concentrations of ethanol, from 0 to 15% v/v. The spectrophotometric and chromatographic results showed that ethanol was not required for proanthocyanidin extraction although its presence increased the rate of extraction. The extraction dynamics indicated that alcohol increased the rate of proanthocyanidin extraction for the first six days of maceration, after which, even in the absence of ethanol, extraction rate was nearly identical for all treatments. These findings suggest that extraction time is an important consideration when managing techniques such as cold soak which are thought not to affect seed proanthocyanidin extraction. ER -