| dc.description.abstract | Blanc Du Bois accounts for a significant growth segment of the Texas Wine In-dustry as it thrives in the terroir and is disease resistant. Variability in the sensory pro-files of Blanc Du Bois wines have been observed. This study examined pre-fermentation methods influencing sensory characteristics and volatile composition of Blanc Du Bois wines. The must was treated with PVPP, and hyper oxygenation prior to alcoholic fer-mentation. They were then rated by a descriptive analysis sensory panel. Panelists devel-oped a lexicon of 24 aromas and 26 flavors. The wines were analyzed for the intensity of each attribute once panelists were trained with references for each attribute on a 16-point scale calibration. Gas chromatography mass spectrometry with dual sniff ports (GC-MSO) was used to assess the volatile composition. Data were analyzed with analysis of variance (ANOVA), principal component analysis (PCA), and partial least squares (PLS) regression.
Significant differences were observed in the wines by treatments and vintage, and correlations between attributes, volatiles, and wines were observed in PCA and PLS models. The first vintage was associated with floral, apricot, green, alcohol/fermented, buttery and sour attributes; and esters, organic acids, alcohols, and a hydrocarbon vola-tiles. The second vintage was associated with the fruity, citrusy, sweet, vinegar, and malty attributes, and hyper oxygenated and control wines associated with esters, and one alcohol, while the PVPP wine correlated mostly with alcohols and esters, two organic ac-ids, miscellaneous sulfur compounds, and one hydrocarbon.
Results indicate that pre-fermentation treatments had minimal impact on the wines, both sensorily and chemically. Although pre-fermentation treatments were effec-tive in improving overripe tropical fruit aroma and alcohol flavor and a reduction in ace-tic acid was observed, it did not have a large impact on sensory and chemical characteris-tics and may have little impact on wine quality and style. | en |
