Electronic Nose Evaluation of the Effects of Canopy Side on Cabernet franc (Vitis vinifera L.) Grape and Wine Volatiles

The effect of grapevine canopy side (north versus south and east versus west) on grape and wine volatiles of Cabernet franc was evaluated during two growing seasons using two electronic nose systems based on conducting polymers and surface acoustic waves. Data from three sampling dates per season from both electronic noses were compared with physicochemistry and wine aroma sensory evaluations. Univariate and multivariate statistical analyses generally indicated grape physicochemistry indices could not differentiate consistently (p > 0.05) between canopy sides across growing seasons and sampling dates. Both electronic nose (ENose) systems provided complete discrimination of canopy sides for grapes and wine using canonical discriminant analysis. On average, the surface acoustic wave-based ENose explained <50% of variation for grapes and <60% for wine using the first principal component, compared to >80% for the conducting polymer-based ENose. Wine aroma sensory evaluation differentiated canopy sides in three of four evaluations.