| Abstract
| - This paper reports the possibilities of on-line reversed-phase HPLC withphotodiode array detection(PDAD) and derivatization with o-phthaldialdehyde (OPA) foridentification of small peptides. Themethodology was initially applied to a wide range of standard peptides.Spectral parameters(wavelengths of the spectrum maxima,convexity interval, and wavelengths of thesecond-derivativespectrum maxima) obtained by PDAD allow identification of thearomatic amino acid residues(tyrosine, tryptophan, and phenylalanine) contained in the peptides aswell as identification of othercompounds from wine that can coelute with peptides (i.e. phenoliccompounds). Postcolumn OPAderivatization allows confirmation of the peptidic nature ofchromatographic peaks. The methodologyhas been successfully applied to peptide fractions (<700 Da) fromcavas (Spanish sparkling wines).Peptides not containing aromatic amino acids and peptidescontaining only phenylalanine,tryptophan, or tyrosine as aromatic amino acids, as well as twocoeluted cinnamic derivatives, weredetected. To the authors' knowledge, these are the most detaileddata reported to date about thecomposition of individual peptides from wine. Keywords: Wine; peptide; HPLC; UV spectra; OPA derivatization
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