Impact of non-volatile compounds on volatiles perception: How proanthocyanidic tannins affect red wine fruity aroma?

Previous research on the fruity character of red wines highlighted that the perception of a “fruity pool” of esters was modified by the presence of fruity or non-fruity compounds with synergistic and/or masking effects. Moreover, some works described that non-volatile compounds may have an important impact on wine perception, but also on odorant compounds volatility. The goal of this work was to assess the olfactory consequences of a mixture between esters and proanthocyanidic tannins, through sensory and physico-chemical approaches. Sensory analyses including triangle tests, detection thresholds, and sensory profiles, were conducted in order to evaluate the sensory impact of pure tannins on red wines “fruity pool” perception. Then, the impact of these non-volatile molecules on esters volatility, and thus taster stimulation, was evaluated thanks to the determination of partition coefficients. Triangular test revealed a significant difference on global perception between the fruity pool containing esters and the same fruity pool in mixture with proanthocyanidic tannins. Sensory profiles evaluation showed fruity notes perception were significantly lower for the fruity pool supplemented with tannins compared to the fruity pool alone in dilute alcohol solution. These results confirmed the sensory importance of some non-volatile compounds on odour perception. Finally, esters partition coefficient evaluation revealed a decrease of the volatility of esters when tannins were present in the matrix, thus corroborating sensory evaluation results. Proanthocyanidic tannins decrease esters volatility when they are added in the matrix, thus reducing orthonasal taster stimulation and consequently reducing red wine fruity notes perception. Such a study should be extended to other wine tannins and anthocyanins, including their concentration ranges, to assess the impact of the phenolic matrix on red wines aroma perception