Rapid tool for distinction of wines based on the global volatile signature.

This work describes a novel methodology for the rapid distinction of wines by headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry, followed by principal component analysis of the data (HS-SPME-GC-MS-PCA). Headspace SPME is used to extract and concentrate the volatile and semi-volatile fractions. A DB-FFAP fused silica GC capillary column of 30 m at 220 degrees C was used acting as a transfer line of the components sorbed by the Carbowax-divinylbenzene coating fibre to the mass spectrometer, which acts as a sensor (30<m/z<300). In this methodology, which does not require any pre-treatment of the sample, the global volatile signature of the wine headspace (chromatographic profile and m/z pattern of fragmentation in each scan) is evaluated without complete chromatographic separation of its components. In order to retrieve from the data as much chemical information as possible and to extract m/z fragments (markers) for the characterisation and distinction of the wines varieties, a PCA was applied to the data resultant from the unresolved volatile fraction. In the present study, two different monovarietal white wines (Vitis vinifera L. var. Fernão-Pires and Arinto) were tested. Associated to the fast character of the proposed methodology and robustness taking into account the extraction time, it is also important to focus the higher sensibility and the lower effect of the sample moisture of the MS sensor response when compared to the conventional e-noses.