| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1242586 | Talanta | 2016 | 7 Pages |
•3D front face fluorescence spectroscopy used to acquire spectral fingerprints of wine polyphenols.•pH modification introduced as a supplementary parameter to increase the information content of fluorescence spectra through its effect on the structure of the polyphenols.•Independent Components Analysis (ICA) used to extract information from the resulting multi-way (samples/pH/excitation/emission) fluorescence fingerprints.•Signals extracted from the spectra at pH7 and pH8 discriminate wines belonging to three grape varieties.
Wine composition in polyphenols is related to the variety of grape that it contains. These polyphenols play an essential role in its quality as well as a possible protective effect on human health. Their conjugated aromatic structure renders them fluorescent, which means that 3D front-face fluorescence spectroscopy could be a useful tool to differentiate among the grape varieties that characterize each wine. However, fluorescence spectra acquired simply at the natural pH of wine are not always sufficient to discriminate the wines. The structural changes in the polyphenols resulting from modifications in the pH induce significant changes in their fluorescence spectra, making it possible to more clearly separate different wines.9 wines belonging to three different grape varieties (Shiraz, Cabernet Sauvignon and Pinot Noir) and from 9 different producers, were analyzed over a range of pHs. Independent Components Analysis (ICA) was used to extract characteristic signals from the matrix of unfolded 3D front-face fluorescence spectra and showed that the introduction of pH as an additional parameter in the study of wine fluorescence improved the discrimination of wines.
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