Ethanethiol and diethyl disulfide (DEDS) most often occurred at levels above their olfactive threshold in wines with nauseous sulfur-linked smells. As ethanethiol is very oxidizable and chemically reactive, a stable isotopic dilution analysis of both ethanethiol and its disulfide in wines using solid phase microextraction and GC-MS was developed. The latter involved the determination of the proportion of DEDS formed by oxidation of the thiol during the analysis conditions, which was obtained by the use of two differently labeled disulfide standards. An original synthesis of labeled ethanethiol standards in conditions minimizing oxidation was developed, and the corresponding labeled diethyl disulfides were obtained from these thiols. This analytical method was used to follow the levels of these sulfur compounds during aging in a young red wine spiked with ethanethiol and added with enological tannins, with or without oxygen addition. The total levels of these two sulfur compounds were shown to decrease steadily after 60 days of aging, up to 83%. The effect of oxygen sped this decrease, but the effect of enological tannins was very slight. Residual ethanethiol was detected in its disulfide form from approximately 36% in the nonoxygenated wines to 69% in the oxygenated samples.

<p style="text-align: justify;"><strong>Aim</strong>: Within the protected designation of origin (PDO) Côtes d’Auvergne, Gamay N wines express unique peppery notes that may reflect high levels of rotundone. We investigated the typicality of these wines by determining their sensory, chemical and consumer profiles.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Twenty-one Gamay N wines from the 2013 vintage from four French wine-growing areas were assessed by a trained sensory panel (n = 8). Principal component analysis and hierarchical clustering of olfactory data were used to describe differences among regions and to select four wines for a consumer study (n = 87). Gamay N wines from Auvergne had more intense peppery notes and higher rotundone concentrations, two characteristics that showed a significant positive correlation. The large variability in rotundone among the 12 wines from Auvergne was attributed to ethanol content, which was correlated to the rotundone levels in the wines. Those who appreciate wines with a peppery sensory profile were generally managers and professionals who are willing to pay more for a bottle of wine.</p><p style="text-align: justify;"><strong>Conclusion</strong>: There were differences in sensory profile and rotundone concentrations in Gamay N wines from cool-climate vineyards. We also identified the consumption profile of those who appreciate peppery wines.</p><p style="text-align: justify;"><strong>Significance and impact of the study</strong>: Our results provide a scientific foundation for Auvergne grape growers to promote the typicality of their wines. This research also identifies the key elements for developing the Côtes d’Auvergne wine range and adapting products to consumer profiles.</p>

The issue of endocrine disruptors is a subject of debate in the agri-food sector and questioning for consumers through the media. Among these compounds, some of the family of phthalates, are used in the composition of some materials used in wineries. This makes it a worrying issue in terms of image and safety. The objective ok this work was to identify the sources of phthalates and the factors favoring their diffusion in wines to propose preventive and curative solutions to the wine makers. The modalities were therefore selected in different French wine regions to represent the diversity of oenological practices. This survey also led to examine more thoroughly the parameters involved in the situations that favored migration of the highest levels. Additional experiments were performed specifically on certain sources or contributing factors. The first identified sources include epoxy resin, fiberglass reinforced polyester as well as PVC materials (pipes …). Favorable factors include alcohol content, temperature, duration and contact area.

Résumé. Deux groupes de 15 sujets ontété sélectionnés selon leur niveau d'expertise en dégustation de vin. Le premier groupeétait constitué de professionnels du vin du Beaujolais habituésà réaliser du profil sensoriel, le secondétait constitué de consommateurs amateurs de vins rouges. Aucun n'avait expérimenté la méthode DTS (Dominance Temporelle des Sensations) auparavant. Six vins rouges ontété sélectionnés pour leur diversité sensorielle : trois vins du Beaujolais et trois de Bourgogne. Durant deux séances d'entraînement, 10 descripteurs (sucré-gras, amer, acide, astringent, fruits confits-cuits, fruits rouges, floral, végétal,épicé, et boisé) ontété définis et expliqués aux deux panels, qui ont aussi pu se familiariser avec le principe du DTS. A chacune des quatre séances suivantes, chaque panel a réalisé un profil DTS de chacun des six vins de l'étude. Les résultats montrent que les séquences de dominances des experts sont différentes de celles des consommateurs, soulignant l'importance de faire appelà des consommateurs pour la description de leur perception lorsque l'on souhaite comprendre leurs préférences. Les experts sont toutefois plus consensuels entre eux, ce qui se traduit par une meilleure discrimination des six vins. Cependant, la répétabilité individuelle, estimée grâce aux quatre répétitions, est légèrement meilleure pour les consommateurs que pour les experts, ce qui laisse envisager une utilisation prometteuse du DTS avec les consommateurs.