Pyrolysis and thermally assisted hydrolysis-methylation gas chromatography mass spectrometry of sound and degraded wine bottle cork

The present paper reports on the utilization of pyrolysis/gas chromatagraphy/mass spectrometry (PY/GC/MS) and thermally assisted hydrolysis-methylation/gas chromatography/mass spectrometry (THM/GC/MS) to characterize cork (Quercus suber L.) of wine bottle stoppers, Sound and degraded cork samples were analysed to verify whether structural differences between the two samples are present, A series of p-hydroxyphenyl, guaiacyl and syringyl phenolic compounds, ascribed to cork polyphenols (suberin and lignin), were identified in the pyrograms. Furan-based derivatives were also detected as the dehydration products of structural polysaccharides (cellulose and hemicellulose). A homologous series of saturated and unsaturated hydrocarbons from C9 to C22 was evident, Finally, pyrolysis in presence of a methylating agent, the technique TRM/GC/MS, allowed the determination of saturated and unsaturated fatty acids which probably originated from thermal degradation of suberin aliphatic fraction, Compared to sound cork, the degraded sample showed relatively more odd-chain hydrocarbons and relatively less even-chain fatty acids contents.