Oxidation of Cabernet Sauvignon wines during secondary shelf life was studied by headspace solid-phase microextraction (HS-SPME) coupled to GC-quadrupole MS (GC-qMS) and sensory tests, with the support of multivariate statistical analyses such as OPLS-DA loading plot and PCA score plot. 4 different oxidation conditions were established during a 1 wk secondary shelf life. Samples collected on a regular basis were analysed to determine the changes of volatile chemicals, with sensory characteristics evaluated through pattern recognition models. During secondary shelf life the separation among collected samples depended on the degree of oxidation in wine. Isoamyl acetate, ethyl decanoate, nonanoic acid, n-decanoic acid, undecanoic acid, 2-furancarboxylic acid, dodecanoic acid and phenylacetaldehyde were determined to be associated with the oxidation of the wine. PCA sensory evaluation revealed that least oxidized wine and fresh wine was well-separated from more oxidized wines, demonstrating that sensory characteristics of less oxidized wines tend toward “fruity”, “citrous” and “sweetness”, while those of more oxidized wines are positively correlated with “animal”, “bitterness” and “dairy”. It was also demonstrated that OPLS-DA and PCA are very useful statistical tools for the understanding of wine oxidation. (We recommend that you consult the full text of this article)

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