Polyphenolic Profile of Orange Wines

Abstract

ObjectivesThe objective of this study is to describe the polyphenolic profile of orange wine and compare it with red wine, additionally this study explores the potential effect of iron content in the orange wine characteristic color. MethodsNine orange wines and 1 red wine were analyzed in triplicate. The skin-contact maceration of the orange wines ranged from 3 days to 6 months. Three orange wines were made following the Georgian traditional method (using Quevri and 6 months skin-contact maceration), one orange wine went through 6 months of skin-contact maceration in oak barrels. Analysis consisted of color density (CD) and hue tint (HT) by measuring absorbance at 420,520, and 700 nm; identification and quantification of the polyphenols gallic acid, vanillic acid, caffeic acid, caftaric acid, 4-caffeoylquinic acid, r-coumaric acid, myricetin, catechin, epicatechin, kaempferol, b-carotene using LC-MS/MS; and iron content using ICP-OES. PCA of polyphenols was also performed. ResultsAccording to the PCA score plot of polyphenols, the three orange wines made following the Georgian traditional method were grouped together with the orange wine that went through 6 months skin-contact maceration in oak barrels closely located in the plot. While orange wines with skin-maceration times of 7 and 3 days were grouped together and clearly separated from those with a 6 months skin-contact maceration. The red wine sample was clearly separated from all the orange wine samples in the score plot. No correlation between color density, hue tint and iron content was observed since iron was not detected in any sample. ConclusionsIt seems to be a correlation between the length of the skin-contact maceration and the polyphenolic profile of orange wine. Funding SourcesCSUN.