The Impact of Adding Viognier Skins to Petit Verdot Fermentations (2017)

This study examines whether adding Viognier skins to Petit Verdot fermentations alters the chemical and sensory qualities of the wine. The goal of adding Viognier skins was to mellow out some of the harsher characteristics of Petit Verdot. Petit Verdot grapes were crushed and split into two separate T Bins. To one bin, 10% w/w of Viognier skins were added (the skins were received a couple of days before processing Petit Verdot and were refrigerated prior to addition). An attempt was made to sort stems out of the Viognier skins. The other bin did not receive Viognier skins. All other treatments between wines were identical. Volatile acidity was slightly higher in the wine with Viognier skins. Color, and several phenolic parameters, were reduced in the Viognier skins treatment. For the triangle test, of 7 people who answered, 2 people chose the correct wine (29%), suggesting that the wines were not significantly different. No preference trends were discernible. For the descriptive analysis, there were no strong trends for the descriptors used in this study. The wines with Viognier skins had a slight tendency towards higher Bitterness, and perhaps higher Astringency. Although the chemistry suggests that the Viognier would reduce the tannic character of the wine, the sensory results suggest otherwise. More studies are needed in order to more fully evaluate the impact of adding white grape skins to red wine fermentations on chemical and sensory qualities.

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