%0 Journal Article %A J. M. Ricardo-da-Silva %A V. Cheynier %A A. Samsom %A M. Bourzeix %T Effect of Pomace Contact, Carbonic Maceration, and Hyperoxidation on the Procyanidin Composition of Grenache blanc Wines %D 1993 %R 10.5344/ajev.1993.44.2.168 %J American Journal of Enology and Viticulture %P 168-172 %V 44 %N 2 %X Lots of Grenache blanc grapes (Vitis vinifera) were submitted to a pomace contact or carbonic maceration and/ or hyperoxidation prior to clarification and fermentation. Changes in several classical wine analytical parameters and wine phenolic composition, including the procyanidin composition, are reported. Wines were purified on a polyamide chromatographic column. A procyanidin fraction was thus obtained and further analyzed by reversed-phase HPLC. To our knowledge, procyanidins trimer C1, trimer 2 [epicatechine-(4β -> 8)-epicatechin-(4β -> 8)-catechin], B1 3-0-gallate, B2 3-0-gallate, and B2 3'-0-gallate were quantified for the first time in white wines. Carbonic maceration wines contained larger amounts of procyanidins, followed by the pomace-contact wines. Hyperoxidation induced important losses of all phenolic compounds analyzed. When its quantification was possible, procyanidin B1 was the major procyanidin in Grenache blanc white wines, although trimeric procyanidins were also present in important amounts. The galloylated-dimeric procyanidins were minor components in white wines. %U https://www.ajevonline.org/content/ajev/44/2/168.full.pdf