## 3 Results and Discussion
### Wine Sensory Attributes of Taste and Mouthfel  
The most prominent taste attribute in the control wines was sourness, which showed the highest average score (5.7), followed by bitterness (2.6), sweetness (1.2), and saltiness (0.3) on a 15 cm line scale (Figure 2). The high intensity of sourness perceived in the Marquette wines could be related to their high tittatable acidity (averaged at 8.3 g/L), as it was noted in an earlier part of this study (Supplementary Table S2) [22]. Wines made from cold-hardy grape varieties, compared to those from _Vitis vinifera_, are generally characterized by greater tittatable acidity [36]. As for the mouthfel properties, astringency (3.0) and hotness (3.1) were the two primary attributes, followed by viscosity (2.7) and tingly (1.2). No significant difference was observed among the treatment groups for these attributes. The hotness was associated with the high alcohol concentration (14.9 vol%) in Marquette wines, as the value reported in Supplementary Table S2. The perception of bitterness and astringency in wines is mainly attributed to the presence of phenolic compounds, notably monomeric or polymeric flavon-3-ols. Our previous study revealed that Marquette red wines treated with ACE-PEC and ACE-RCE exhibited significantly higher concentrations of (+)-catechin, (-)-epicatechin, and condensed tannins. Furthermore, the mean degree of polymerization of condensed tannins, as determined in our previous analysis, averaged at 2.6, implying that these compounds were primarily present as dimers or trimers. These compounds tend to impart more bitterness than astringency [16]. Despite the differences in phenolic compound concentrations resulting from the various treatments, no significant effects were observed on the taste or mouthfel attributes. In contrast, ACE treatment of Pinot noir grapes during winemaking led to a nearly 7-fold increase in the concentration of condensed tannins compared to the control after aging, which in turn led to an increased intensity of both astringency and bitterness during sensory evaluation [17]. A similar improvement in tannin concentrations and astringency intensity was also observed in ACE-treated Shiraz red wines [18]. In addition to bitterness and astringency, ACE treatment did not significantly affect the perception of other taste and mouthfel attributes, including sourness, sweetness, hotness, and viscosity in studies conducted on both Pinot noir [17] and Shiraz wines [18]. Figure 2: Sensory analysis: taste and mouthfel attributes of Marquette red wines after nine months of aging. Moreover, previous studies have indicated that using macerating enzymes, which mainly contain endo-polygalacturonase, can improve Cabernet Sauvignon wine quality by promoting the extraction of condensed tannins, resulting in a 13% increase in astringency intensity [20]. However, the same prior study also noted that enzyme treatment shifted the descriptors of astringency from positive (velvety and soft) to negative (grippy and chalky) [20]. It is worth noting that the concentrations of condensed tannins in these previous studies under control conditions (310 mg/L in Shiraz and 800-1200 mg/L in Cabernet Sauvignon red wines) were significantly higher than the concentration found in Marquette red wines (70 mg/L). In comparison, the use of ACE treatment only triggered a slight modification in the composition of soluble polysaccharides in Marquette red wines, whereas macerating enzymes significantly degraded the structure of Polysaccharides Rich in Arabinose and Galactose (PRAG), by removing the arabinose side chains and promoting the release of rhamnocaluronan (RG)-II. These trends have been observed from our prior measurements of this study and are consistent with previously published studies in enzyme-treated Carignan red wines [13] and Merlot red wines [37].