## 3 Results and Discussion
### Sensory Impact of Intrspecific Diversity  
At the end of the alcoholic fermentation, the wines from the organic replicates of each yeast modality were pooled, sulfited, filtered, bottled, and stored for one month. Frequency citations of each attribute were computed for each sample. The resulting contingency matrix was subjected to a correspondence analysis (CA), shown in Figure 5. The first two principal components of this CA, Dim1 and Dim2, explained 50.32% of the variance. The distribution of wine samples displayed a considerable separation between wines made with distinct yeast strains. Hierarchical cluster analysis (HCA) was carried out on wine coordinates on the two first dimensions of the CA. The samples were separated into three main groups, represented in various colors (Figure 5). The first group (in blue), located in the positive values of the first dimension, included samples S1, S7, S10, S11, and S3, which can be described by the attributes: \"grapefruit\", \"wet mop\", \"rancid\", \"vegetal\". The second cluster (in green) was composed of wines from fermentations conducted with the S5, S9, S2, and S12 strains and were located on the negative side of the first dimension. Within this cluster, S2 and S12 were characterized as \"banana\" and \"English candy\", while S5 and S9 were \"chemical\" and \"fruity\". The last group (in pink), composed of strains S4, S6, and S8, was characterized by oxidation terms as \"quince paste\", \"honey\", \"butter\". Our results showed quite distinctive aroma profiles among the strains studied, demonstrating intraspecific diversity at the sensory level [52; 53]. It was even possible to discriminate finished wines fermented by certain related strains. The S2 strain, resulting from the evolutionary adaptation of the S1 strain, belonged to different sensory classes, and hence, led to distinct sensorial profiles. Nevertheless, this was not the case for the S7 hybrid and the parental S10 strains. Despite the significant role of volatile compounds, their presence could not simply explain the sensory differences [54; 55]. Moreover, despite a complex matrix, interactions between volatile compounds, and important differences in the perception threshold between the different aromatic volatile compounds, some descriptors could be related to volatile organic compounds. A high concentration of isoamyl acetate for strains S2 and S12 was significantly associated with very fruity terms, including \"banana\" and \"English candy\", as mentioned in previous studies [44; 56]. Concerning the vegetal term, we found a significant correlation with 1-hexanol, 1-heptanol, which has also been reported by other authors [57; 58]. Moreover, 1-propanol was significantly linked to the term \"rancial\", which had already been related to pungent flavors [20]. As for the two other approaches, it was possible to distinguish the finished wines produced thanks to the different strains of _Saccharomyces cerevisiae_ used. The metabolic differences were, in fact, expressed in distinct phenotypes with regard to volatilome and sensory properties. We could see that the groups established based on the volatile composition analysis of the metabolome did not correspond exactly to the classes established from the sensory analysis. Furthermore, we observed that only a few sensory descriptors could be correlated to volatile compounds, as previously stated. Thus, this confirms previous studies, which revealed the difficulty of correlating the sensory aspect and the dosage of volatile compounds. Synergetic phenomena were observed between volatile compounds [59]. Conversely, the masking of a volatile compound by another was demonstrated [57; 60; 61]. Thus, the interactions between volatile compounds lead to diverse aromatic profiles. Moreover, in this study, the dosage of volatile compounds remained non-exhaustive and therefore not representative of the aromatic profile of wine at the sensory level. To our knowledge, this was the first time that these three complementary approaches were combined for a comparative study.