Physicochemical model to interpret the kinetics of aroma extraction during wine aging in wood. Model limitations suggest the necessary existence of biochemical processes.
A model based on physicochemical parameters has been developed and applied to the study of the kinetics of extraction of aroma compounds from oak casks having been used a variable number of times. Two major deviations from the model can be observed: a strong seasonal dependence of extraction (unexpected in a thermostated cellar); and higher yields with a smaller number of longer extractions. 4-Propylguaiacol follows both behaviors, and its levels have been found to be closely related to those of 4-ethylguaiacol and to the number of uses of the barrel, which suggests that this compound may be formed by the same microorganisms forming ethylphenols from a precursor found in wood. Although the extraction kinetics of all aroma compounds appear to be more or less mediated by the action of microorganisms, those of whiskeylactones, eugenol, and 4-allyl-2,6-dimethoxyphenol are more in accordance with the physicochemical model, whereas those of vanillin, syringaldehyde, furfuryl alcohol, and, of course, 4-propylguaiacol are much more coherent with a microbiological extraction/formation.
Ferreira
Vicente
V
Laboratory for Flavor Analysis and Enology, Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza, Spain. vferre@unizar.es
Jarauta
Idoia
I
Cacho
Juan
J
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005511:Food Handling / Q000379:methods; D005662:Furaldehyde / Q000032:analysis; D006139:Guaiacol / Q000031:analogs & derivatives / Q000032:analysis; D007700:Kinetics; D007783:Lactones / Q000032:analysis; D009812:Odorants / Q000032:analysis*; D029963:Quercus; D012621:Seasons; D013997:Time Factors; D014920:Wine / Q000032:analysis*; D014934:Wood
D007783:Lactones; D006139:Guaiacol; C511024:4-propylguaiacol; D005662:Furaldehyde