Analysis of volatile odor compounds and aroma properties of European vinegar by the ultra-fast gas chromatographic electronic nose

Vinegar is a very popular condiment with different species and aroma profiles. Eighty-three volatile odor compounds (VOCs) were identified from European vinegar using ultra-fast gas chromatographic electronic nose (UFGC E-nose), of which there were 61 VOCs with odor activity value (OAV) ≥ 1. Among the 61 VOCs, acetic acid, ethyl isovalerate, propionaldehyde, butanoic acid, ethyl cinnamate, and guaiacol contributed significantly to the aroma property and type of European vinegar. There were obvious clustering trends of apple vinegar, wine vinegar, and balsamic vinegar in principal component analysis (PCA). The clustering of the vinegar-like groups was more obvious in orthogonal partial least squares discriminant analysis (OPLS-DA). The volatile markers discriminating vinegar, including acetic acid, propionic acid, pyrazine, furfural, isopropyl alcohol, and so on, were screened out by variable importance for the projection (VIP). These results demonstrated that UFGC E-nose is a novel, rapid and non-destructive analytical tool and can also be used for identifying aroma compounds and tracing the food species.