# Influence of Region on Sensory and Chemical Profiles of Pennsylvania Gruner Veltliner Wines
## 2 Materials and Methods
### Viiiification  
An average of 91.0 kg of fruit was hand harvested at each site and transported to the Department of Food Science at The Pennsylvania State University (University Park, PA, USA) where it was stored for less than 48 h at 4 \({}^{\circ}\)C before processing. After crushing and destemming, must was pressed to a yield of 50.08 L of juice per 100.0 kg of grapes using a bladder press. Juice was treated with Cinn Free (Scott Laboratories, Petaluma, CA, USA), a pectinolytic enzyme, at a rate of 15 mL/L. Juice was also treated with SO2 in the form of potassium metabsulfite (KMBS; Presque Isle Wine Cellars, North East, PA, USA) prior to cold settling; adjustment rates were dependent on cluster rot assessment and ranged from 30 to 50 ppm in Year 1 and 30 to 40 ppm in Year 2. After cold settling overnight, juices were racked and chaptalized with sucrose to achieve a final total soluble solids (TSS) level of 22 \({}^{\circ}\)Brix across all treatments. If a given juice was above pH 3.4, its pH was adjusted to 3.4 using tartaric acid (Presque Isle Wine Cellars, North East, PA, USA). Similar adjustments have been made in prior wine regionality work [11; 17; 18]. In this study, we based the winemaking protocol on common PA winemaking practices for Gruner Veltliner, where chaptalization and pH adjustment are common. In addition, several studies on wine regionality also standardized final ethanol content through juice chaptalization (e.g., [11]), and some also acid adjusted (e.g., [17]). As demonstrated by [PERSON] et al. [18], juice chaptalization of Sauvignon blanc wines did not significantly affect wine aroma attributes across three harvest dates (except for stonefruit aroma in harvest 1, sweetness, acid balance, body, and length) compared to non-chaptalized wines. Furthermore, wine typicality ratings were mainly affected by grape ripeness rather  
Figure 1: Location of vineyard sites within recognized regions of the Pennsylvania Wingry Association (PWA; pennsylvanian-awine.com, accessed on 10 April 2020). Vineyards with the same color belong to the same region. than sugar adjustment in that study. We therefore decided to chaptalize juices as from experience we knew that the different sites differed in grape soluble sugar content. As ethanol is a significant factor in sensory perception of wines (e.g., [19]), we aimed to target equivalent final ethanol contents in all wines across both years. The adjusted juices were racked into two 5 gallon (18.93 L) glass carboys prior to inoculation with yeast. Due to low juice yields for some sites in Year 1, two experimental sites were fermented in 1 gallon (3.79 L) glass jars and one site was fermented in 3 gallon (11.36 L) carboys. In Year 2, one of the 7 sites was fermented in 3 gallon carboys. Each fermentation replicate was inoculated with _Saccharomyces cerevisiae_ EC-1118 yeast (Lallemand, Petaluma, CA, USA) at a rate of 0.25 g/L with an addition of 0.30 g/L Go-Ferm nutrient (Lallemand). Fermentations were temperature controlled in Year 1 using glycol jackets (Gotta Brew, Sacramento, CA, USA) maintained at 15 \({}^{\circ}\)C and in Year 2 using a chilled water bath system with a glycol chiller set to 12.8 \({}^{\circ}\)C. In both years, fermentation temperatures were both typical of white wine fermentation [20; 21] and in alignment with Gruner Veltliner fermentation practices in PA [22]. Yeast assimilable nitrogen (YAN) adjustments were performed 24 h post-inoculation and at one-third sugar depletion using Fermaid K nutrient (Lallemand) to achieve a final concentration of 0.25 g/L. Alcoholic fermentation was monitored daily by TSS readings via hydrometry. When TSS values measured below 0 \({}^{\circ}\)Brix, AimTab Reducing Substance tablets (Germaine Laboratories, San Antonio, TX, USA) were used to confirm dryness of wines, defined as \(\leq\)1% residual sugar. Fermentations were held at 4 \({}^{\circ}\)C for cold settling, subsequently racked off lees, and treated with the enzyme blend Scottzyme KS (Scott Laboratories) at a rate of 79.25 \(\upmu\)L/L.