GC-MS STUDY OF VOLATILES OF NORMAL AND MICROBIOLOGICALLY ATTACKED CORK FROM QUERCUS-SUBER L

The volatile compounds of cork were studied by gas chromatography and combined gas chromatography-high-resolution mass spectrometry using si multaneous distillation-extraction to prepare the samples. To assess t he origin of the volatiles, three different types of samples were anal yzed: ''normal'', attacked by Armillaria mellea, and infested by molds . The study of the volatiles of these different types of corks allowed the identification of the chemical modifications rich may occur in co rk polymers. The cork attacked by A, mellea showed higher amounts of p henols, vanillin, benzaldehyde, benzyl alcohol, and chlorinated compou nds than normal cork; this may indicate lignin degradation. The cork i nfested by molds contained higher levels of 3-methyl-1-butanol, 1-octe n-3-ol, l-octanol, 2-methylisoborneol, chlorinated compounds, and meth ylketones. These components resulting from microbial metabolism were a lso present in cork attacked by A. mellea. The use of cork attacked by A. mellea is not recommended in the manufacture of cork stoppers, sin ce these types of cork have volatile compounds likely to cause off-fla vors in wine. For the same reason it is important to reduce the likeli hood of mold development during the standing period.