Modified carbon paste screen printed electrodes forrapid fingerprinting of white wine oxidizable fractions
Oxidative reactions occurring upon accidental or deliberate exposure of wine to oxygen are common during wine production and storage, resulting in either beneficial or detrimental effects mainly depending on oxygen quantities and wine type.Wine typically contains a complex pool of oxidizable compounds, including phenolics, ascorbic acid, SO2, different thiols and so on.Initial reaction with oxygen involves oxidation of ortho-diphenols to form quinones, which can in turn react with the other oxidizable compounds.Types and extents of these reactions occurring may depend on some individual species and/or their relative proportions, such as the presence of catalysts, pH, temperature, and probably other hitherto unidentified factors.Voltammetric techniques have been successfully applied to the analysis of different oxidizable compounds, including phenolics which are the primary target of wine oxidation.Recent progresses in this field have led to the development of disposable electrodes, allowing to bypassing the tedious electrode cleaning procedures associated with voltammetric analyses of phenol-rich matrices.Applications of such electrodes for white wine analysis have been reported but still remained limited so far.In this study, the electrochemical response of modified carbon paste disposable electrodes towards major white wine oxidizable compounds (catechin, caffeic, gallic, coutaric, ferulic and ascorbic acids, quercetin, SO2 and glutathione), either alone or in mixtures, were studied.Voltammograms were acquired in the 0-1200 mV region, allowing to defining the characteristic voltammetric features of the different compounds, alone or in binary mixtures.A set of 15 commercial French wines, consisting of Muscadet (6), Chardonnay (3), Riesling (4) and Viognier (2), were then analyzed under the same conditions to obtain voltammetric fingerprints of the oxidizable compound pool of each wine.Major differences in the voltammetric profiles obtained were observed, in particular in the region around 500 mV, corresponding to ortho-diphenols and other easily oxidizable compounds.The ability of the electrodes to discriminate the different wines was evaluated by a chemometric approach involving different pre-treatment strategies in conjunction with PCA and PLS-DA multivariate methods.Discrimination of the four wine types could be obtained, indicating that this analytical approach can provide a useful tool in the characterization of the oxidizable substrate pool of different white wines.
Oxidation Foot-printing White wine Voltammetry
Asael Gonzalez Zavala Jeremie Wirth Jean-Baptiste Dieval Stephane Vidal Maurizio Ugliano
Nomacorc France, Domaine de Donadille, Av.Yves Cazeaux, 30230, Rodilhan, France;ESA Angers, 55 rue R Nomacorc France, Domaine de Donadille, Av.Yves Cazeaux, 30230, Rodilhan, France
国内会议
赣州
英文
219-220
2015-04-20（万方平台首次上网日期，不代表论文的发表时间）