## 1 Introduction
Generally, red wines contain between 12% and 14% of ethanol and commercial strains of _S. cerevisiae_ have been reported to be able to tolerate up to 13% ethanol [18]. However, depending on the yeast strain, cell growth and viability can be inhibited by high ethanol concentrations, and thus limit fermentation productivity and ethanol yield [19; 20; 21; 22]. Therefore, physiological properties of yeast strains such as SO\({}_{2}\) and ethanol tolerance is important to support the use of non-_Saccharomyces_ yeasts in winemaking applications. Wine flavor is a complex interaction of nonvolatile and volatile chemical constituents that contribute to taste and smell. Certain core compounds such as ethanol, glycerol, organic acids, and residual sugars contribute to the primary taste of wine. Sensory panelists perceive these core nonvolatile compounds as a mouth-warming effect, viscosity, sourness, and sweetness. These core compounds are fundamental components of wine which an individual experiences via sense [23]. On the other hand, volatile compounds in wine are composed of hundreds of different compounds with concentrations ranging from 10\({}^{-1}\) to 10\({}^{-10}\) g/kg typically perceived as wine aroma [24]. Wine associated volatile metabolites are a result of three processes, (1) metabolism of grape-derived compounds into active aroma compounds, (2) biosynthesis of fermentation-derived metabolites, and (3) post-fermentation practice-derived metabolites such as barrel aging [25]. Previous literature have identified methoxyprazines, C13-norisoprenoids, volatile sulfur compounds, and terpenes as the major contribution to primary aroma, and volatile fatty acids, higher alcohols, esters, and aldehydes as contribution to secondary aroma [26; 27]. However, the balance and interaction of these chemical compounds determine the wine quality. The biosynthesis of these compounds depends on the microorganism present in winemaking. Therefore, in order to isolate and identify novel non-_Saccharomyces_ yeast strains for applications in winemaking, it is critical to analyze core volatile and nonvolatile metabolites of individual strains. The annual economic impact of the wine industry in the State of Pennsylvania is approximately USD 2.5 billion with more than 300 wineries across the State. Pennsylvania is ranked fifth for wine production in the USA [28; 29]. The overall objective of this study is to determine the potential contribution of hybrid grapes-associated non-_Saccharomyces_ yeasts for use in winemaking to enhance regionality of local wines. Cultured-based methods coupled with ITS sequencing were used to isolate and identify Chambourcin-associated non-_Saccharomyces_ yeasts from three regional vineyards in Pennsylvania. UHPLC-RI and GC-MS were used to measure volatile and nonvolatile compounds within inoculated fermentation using five candidate non-_Saccharomyces_ yeast in a sterile Chambourcin grape juice system. Here, we focus on volatile metabolite changes that drive differentiation between candidate non-_Saccharomyces_ yeasts compared to the commercial benchmark strain, _S. cerevisiae_. We hypothesize that non-_Saccharomyces_ yeasts isolated from hybrid grapes like Chambourcin can enhance regional characteristics of hybrid grapes and potentially increase the quality and appreciation of hybrid wines.