Comparison Among the Analytical Methods

By HS-SPME using a PDMS coated fiber, a rather low adsorption for 2-phenylethanol and also, perhaps tenfold more, for 1-hexanol, is 

3-methylbutanols (isoamyl alcohols) 2. ethyl hexanoate 3. hexyl acetate 4. linalyl ethylether 5. 1-hexanol 7. ethyl octanoate 8. neryl ethylether 9. ethyl 7-octenoate 10. geranyl ethylether 11. vitispiranes 12. a diol ethylether 13. linalool 14. ho-trienol 15. ethyl decanoate 16. citronellyl acetate+isoamyl octanoate 17. a-terpineol 18. ethyl 9-decenoate 19. citronellol 20. 2-phenethyl acetate 21. (3-damascenone 22. hexanoic acid 23. geraniol 24. ethyl dodecanoate 25. 2-phenylethanol 26. octanoic acid 27. decanoic acid 

As a consequence of the sensitivity of the method, higher values of the slope are reported for the hexanoate, octanoate and decanoate ethyl esters, and secondly for the isoamyl and 2-phenethyl acetates. On the contrary, 2-phenylethanol and ethyl acetate showed the smallest enrich- 

Applications of the Kaltron method and GC-MS in wine aroma analysis were reported by Rapp et al. (1996). The study of the data repeatability in the analysis performed using both Kaltron (Rapp et al., 1994) and polystyrene XAD-2 resin (Gunata et al., 1985 Versini et al., 1988 Voirin et al., 1992) extraction, has already been performed in the cited papers. Besides this, a test with eight repetitions of the whole analytical process using XAD-2 resin has been performed both on a non-floral (Pinot blanc) and a floral (Morio-Muskat) varietal wine for the quantification of 25 varietal and fermentation compounds (Carlin, 1998) for each wine sample the mean CV % values ranged from about 7.0 to 7.5 with a standard deviation from about 3 to 4.7 %, respectively, depending on the different level of some compounds, mostly monoter-penes, in each wine type. 

Among esters, compounds relevant in the characterization of the fruity aroma of wine are isoamyl acetate, hexyl acetate, 2-phenylethyl acetate and the ethyl esters of the hexanoic, octanoic and decanoic acids. Diethyl succinate is considered as an index of wine ageing and bacterial activity. For all these compounds and the corresponding fatty acids, there is a good linear correlation between XAD-2 enrichment and Kaltron liquid-liquid extraction. A little higher extraction, related to the internal standard, of Kaltron with respect to XAD-2 resin is obtained for most esters and acids, but not for the diethyl succinate and the 

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