Juliana Pazos, Danielle Fox, Thomas Collins, and James Harbertson*
*Washington State University, 2710 Crimson Way, Richland, WA, 99354-1671 (jfharbertson@wsu.edu)

Cabernet Sauvignon grapes were harvested in 2019 from a Columbia Valley vineyard at three different maturities. At each harvest, musts were adjusted to three different alcohol concentrations (20, 24, 28 Brix). For each maturity-alcohol concentration combination, an eight-month maceration was carried out along with the respective controls (10 days). Descriptive analysis was carried out using 11 trained panelists. Sixteen aroma, three taste, and three mouthfeel attributes were evaluated. Significant differences were found for all taste and mouthfeel attributes (hotness, viscosity, astringency, sourness, bitterness, and sweetness). Seven aroma attributes were found to be significant (light fruit, dry fruit, vegetables, chemical, cheesy/yeast, alcohol aroma, and overall aroma). Analysis of variance (ANOVA) and principal component analysis (PCA) were performed on the data. PCA explained 69.51% of the variation on the first two components. Both the first component (47.66% of variation) and the ANOVAs showed that the lower alcohol concentration was related to higher sourness and light fruit aromas, while high alcohol content was related to higher viscosity, hotness, sweetness, chemical, alcohol, and overall aroma. The second component (21.85%) separated the samples according to maceration treatment and showed that extended maceration was related to increased astringency, bitterness, and dry fruit. Three-way ANOVA showed a significant interaction between the three variables for astringency and a significant alcohol-harvest interaction on bitterness, with higher alcohol content increasing the intensity of both descriptors, but the impact of harvest was inconsistent. Veggie aroma was significantly highest in the first harvest, low alcohol control wine than in all other treatments, which were not different from each other, suggesting that both chaptalization and long-term, extended maceration were effective at reducing vegetal aromas in wine. Overall, the results suggest that harvest time was less important than alcohol concentration and maceration on the sensory results.

Funding Support: Washington State University, Auction of Washington Wines and all Washington State winegrape growers and wineries through the Washington State Wine Commission.