Identification and quantification of impact odorants of aged red wines from Rioja. GC-olfactometry, quantitative GC-MS, and odor evaluation of HPLC fractions.
An XAD-4 extract from a 5-year-old wine from Rioja (Spain) was analyzed by aroma extract dilution analysis. Most of the odorants were quantified by GC-MS. A second extract was fractionated in an HPLC system with a C-18 semipreparative column. Fifty fractions were recovered, their alcoholic degree and pH were further adjusted to those of the wine, and those fractions that showed strong odor characteristics were further re-extracted and analyzed by GC-O and GC-MS. Reconstitution experiments were carried out to confirm the role of the odorants detected in the fractions. Fifty-eight odorants were found in the Rioja wine, 52 of which could be identified. Methyl benzoate was found to be a wine aroma constituent for the first time. The most important odorants are 4-ethylguaiacol, (E)-whiskey lactone, 4-ethylphenol, beta-damascenone, fusel alcohols, isovaleric and hexanoic acids, eugenol, fatty acid ethyl esters, and ethyl esters of isoacids, Furaneol, phenylacetic acid, and (E)-2-hexenal. Comparison among the three techniques shows good agreement and demonstrates that they are complementary.
Aznar
M
M
Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50.009 Zaragoza, Spain.
López
R
R
Cacho
J F
JF
Ferreira
V
V
D002849:Chromatography, Gas / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D009812:Odorants / Q000032:analysis*; D019685:Rosales / Q000737:chemistry*; D013030:Spain; D013649:Taste; D014920:Wine / Q000032:analysis*