## 1 Introduction
Therefore, the balance and concentration of these compounds are important factors in determining the quality and sensory characteristics of the wine [10]. In addition to volatile aroma compounds, phenolic compounds extracted from grape berries and distributed in red wines have been widely related to complex sensory perceptions including appearance and mouthfeel. Anthocyanins and their derivatives are pigments that contribute to red wine color attributes [11]. The initial assessment of a wine, even before aroma and taste, begins with the visual evaluation of appearance and color characteristics, such as hue and color intensity. Hue refers to the color tone of the wine when observed visually from red-tawny to red-purple, indicating the progression of monomeric anthocyanins, copigmentation, and the formation of polymeric pigments during wine aging [12]. Color intensity, on the other hand, assesses the depth or saturation of wine color, influenced by grape variety, winemaking techniques, and the development of stable pigments during aging [13; 14]. Both hue and color intensity provide valuable insights into the age of wines and contribute to the overall sensory impression. Hence, the stability of these color attributes in red wine is critical to a consumer's sensory experience [3]. Condensed tannin is another crucial phenolic compound responsible for the development of stable pigments and wine mouthfeel, which depends on their structural composition and size. They provide balance in the wine's matrix composition, which includes residual sugars, acids, and polysaccharides, among others [3; 15]. Specifically, tannins extracted from grape skins are associated with pleasant and velvety astringency descriptors, positively impacting the overall quality of red wine. In contrast, the extraction of seed tannins may be viewed negatively from a sensory perspective, as seed tannins tend to elicit a more intense bitterness rather than astringency due to their relatively short structure or low degree of polymerization [16]. Given the significant impact of phenolic compounds on red wine quality in terms of mouthfeel and color characteristics, advanced winemaking techniques are focused on improving the extraction of anthocyanin-derived pigments and condensed tannin from grape skin tissues during the fermentation process. Among these techniques, Accentuated Cut Edges (ACE) and the use of macerating enzymes like pectinases are notable examples. ACE mechanically breaks down grape skin structure, while pectinases enzymatically facilitate the cell wall breakdown, both aiming to promote the extraction of phenolic compound extraction during winemaking. For red wines made from _Vitis vinifera_ grapes, ACE treatments significantly improved color density by 68% in cv. Pinot noir red wines, and this was associated with intensified astringency and dark fruit aroma, as perceived by trained panelists [17]. However, while ACE treatment enhanced the perception of astringency in cv. Shiraz red wines, it resulted in an increase in the flavors of earthy and dusty notes and a lesser enhancement in color density of only 17% [18]. These inconsistencies show that the impact of winemaking techniques on red wine quality strongly depends on the grape cultivar and necessitates comprehensive evaluation. The enhancement of color intensity and astringency perception, leading to a better-balanced wine structure, has been widely observed when applying macerating enzymes to _V. vinifera_ wines, including cv. Monastrell wine [12], Shiraz wine [19], and Cabernet Sauvignon wines [20]. In contrast, interspecific cold-hardy grapes (e.g., cv. Marquette and Frontenac), which are extensively grown in the Upper Midwest regions, exhibit unique chemical properties, including high acidity and low astringency sensory properties. There has been limited investigation into the aroma [2; 5], color, and sensory characteristics [21] of red wines made from cold-hardy grapes, particularly after the application of winemaking techniques aimed at improving tannin.