# Influence of Region on Sensory and Chemical Profiles of Pennsylvania Gruner Veltliner Wines
## 3 Results and Discussion
### Descriptive Analysis
Wines are shown with 95% confidence ellipses and colored by region. Attributes ending in \(A\) indicate orthonasal aroma, F indicate in-mouth flavor, MF indicate mouthfeel, and T indicate taste attributes. SE region, located along the negative PC 1 axis, were lowest in yellow color. Conversely, thiol aroma and flavor, ethanol flavor, and warm/hot mouthfeel as opposed to sour taste drove separation along the second dimension; the three samples which were rated highest in these attributes (SE1, 3, and 4), were positively loaded on PC 2, while the NC wine was rated highest in sour taste, and thus, located on the negative PC 2 axis. Sour taste showed a negative correlation to warm/hot mouthfeel, which was significantly loaded onto PC2, and ethanol flavor. In Year 2 (wines made in 2019), the trained panel found the wines to differ significantly in both appearance attributes, three aroma attributes (canned vegetable, thiol, floral), four taste and mouthfeel attributes (sour, sweet, and salty taste, asringent mouthfeel) and three flavor attributes (thiol, citrus, and green apple; data not shown). There was a significant fermentation replicate effect for green apple flavor. Multiple attributes were significantly different in both years, namely yellow color, haziness, thiol aroma and flavor, and sour taste (data not shown). All of the significantly different wine attributes, with the exception of floral and canned vegetable aromas, also showed significant differences by region for Year 2 (Table S4). Wines from the NW region (n = 6) were again the highest in yellow color ratings and were rated significantly higher than wines from the NC and SE regions. NW wines were also rated as significantly less hazy than SE wines, which was consistent with Year 1 results. In Year 1, haziness and yellow color were negatively correlated to each other; however, these attributes were independent of each other in Year 2. NW wines were also rated highest in sour taste, asringent mouthfeel, citrus flavor, and green apple flavor, and differed significantly in sour taste, sweet taste, and citrus flavor attributes from the NC and SE regions. While grape maturity likely contributed to higher yellow color ratings for NW wines in Year 1, fruit harvested from two of the three NW sites were least mature in Year 2 (see Table S3). However, since these wines had higher acidity, less SO\({}_{2}\) was added to these wines after fermentation, as less sulfur dioxide was needed to achieve 0.8 g/L molecular SO\({}_{2}\) at lower pH. Since there was less sulfur in these wines to act as an antioxidant, it is possible oxidation reactions caused a darker, more yellow color to form in these wines, resulting in panelists rating NW wines highest in yellow color for Year 2 despite the fruit being less mature. The NC sample was highest in sweet taste and differed significantly from wines from the NW and SE regions. These ratings were expected, as the NW1 wine, followed by NW2 and NW3, had the highest TA values among the samples, while both fermentation replicates of the NC region wine had the highest RS values (Table S5). It is possible that panelists rated NW samples highest in citrus and green apple flavors due to the association of sourness with these attributes, which is supported by a significant correlation (\(r\)(13) = 0.59, \(p\) = 2.79 \(\times\) 10\({}^{-2}\) for green apple flavor and sour taste; \(r\)(13) = 0.87, \(p\) = 5.82 \(\times\) 10\({}^{-5}\) for citrus flavor and sour taste). The three SE wines were rated significantly higher in thiol aroma and flavor than wines from other regions. This was again similar to the results from Year 1. When examining the PCA biplot for Year 2 results (Figure 2B), similar sample separation trends were found compared to Year 1. All significant attributes were used in the PCA, and 71.67% of variation was captured within the first two dimensions. The three NW wines again grouped together in the bottom right quadrant.