Departamento de Engenharia Química, Universidade de Coimbra, Pólo II, Rua Sílvio Lima, 3030-790 Coimbra, Portugal.
Anal Chim Acta. 2010 Feb 5;659(1-2):93-101. doi: 10.1016/j.aca.2009.11.060. Epub 2009 Dec 2.
Madeira wine has been studied with the main goal of acquiring a better understanding about the evolution of its properties over time. For that purpose, flexible and reliable data analysis tools were employed to characterize wines at different ageing stages, using flavour chromatography measurements. In this paper we present the results from such a study, where the main differences in the aroma profiles and their development in different types of aged Madeira wines are analyzed and evaluated according to their discriminating power. An exploratory multivariate data analysis was conducted using two different tools, namely biplots and contributions plots obtained through principal component analysis (PCA). In order to take advantage of the maximum amount of information provided by the chromatography data sets, a new approach that incorporates samples variability in the analysis of the statistical significance of contributions estimates, was developed and tested. In this way, it was possible to analyze which volatile compounds have statistically significant and/or similar contributions regarding the observed separation of wine samples from different groups. Furthermore, since several chemical compounds are expected to change together as a result of the ageing-related chemical reactions, they were clustered according to a similarity criterion relative to their importance in the trends observed in the scores space. Results obtained provide a sound basis for the differentiation and characterization of the ageing process followed by Madeira wines.
马德拉酒的研究主要目的是为了更好地了解其性质随时间的演变。为此，采用灵活可靠的数据分析工具，使用风味色谱测量来描述不同陈酿阶段的葡萄酒。本文介绍了此类研究的结果，根据区分能力分析和评估了不同类型陈年马德拉葡萄酒的香气特征及其在不同类型陈年马德拉葡萄酒中的发展差异。使用两种不同的工具，即双标图和通过主成分分析（PCA）获得的贡献图，进行了探索性多变量数据分析。为了充分利用色谱数据集提供的最大信息量，开发并测试了一种新方法，即将样品变化纳入贡献估计的统计显著性分析中。通过这种方式，可以分析哪些挥发性化合物在观察到的不同组别的葡萄酒样品的分离方面具有统计学意义和/或相似的贡献。此外，由于几种化学化合物预计会由于与老化相关的化学反应而一起变化，因此根据它们在分数空间中观察到的趋势的重要性，按照相似性标准对它们进行了聚类。所得到的结果为区分和表征马德拉葡萄酒的老化过程提供了可靠的基础。
