Chardonnay is a neutral grape variety offering a diversity of wine styles that are popular amongst consumers. The links between wine production methods and Chardonnay wine volatile composition, as determinants of quality, require further elucidation. Over 80 commercial Australian Chardonnay wines were assessed by expert panelists who were asked to define four distinct levels of quality in a blind tasting. Wine aroma volatiles in each wine were analyzed by SPME-GC-MS and multivariate statistical techniques were used to examine the relationship between volatile composition and quality as defined by the experts. Of 39 aroma compounds quantified, 9 volatiles (including cis- and trans-oak lactones, furfural and diethyl succinate) were significantly and positively correlated with Chardonnay wine quality, whereas 11 volatiles (including fruity esters and monoterpenoids) were negatively correlated. Compounds related to contact with oak and malolactic fermentation were present at highest concentrations in higher quality wines as perceived by wine experts. Lower scores were attributed to younger but less complex wines, which were richer in fruity esters and other grape-derived compounds. A model was developed using partial least squares regression based on these results, which permitted the classification of the Chardonnay wines into high, medium and low quality brackets depending on their relative concentrations of cis- and trans-lactone, ethyl lactate and 2-methyl-1-propanol (positive), and of 1-propanol and 1-hexanol (negative). A significant and positive correlation (r = 0.469, p <0.0001) was found between retail price and quality score, underlying the usefulness of price as an indicator of quality, although it failed to entirely explain quality (as judged by experts) and should therefore be used in conjunction with other quality cues.
- ©2016 by the American Society for Enology and Viticulture