Temporal check-all-that-apply characterization of wine finish
Wine finish, a temporal wine property, is composed of the flavours, tastes, and mouthfeels that linger after swallowing wine and is used an indicator of wine quality. To investigate the impact of ethanol on wine finish evolution, wines with different matrix composition were created, then evaluated using Temporal Check-All-That-Apply (TCATA) methodology. Wines were produced from musts adjusted to varying initial sugar content (21 and 27 °Brix) to create wines varying in ethanol content, Low and High (10 and 15.5% v/v, respectively). Post-fermentation, a portion of the low ethanol wine was used to create a third treatment, Low-to-high, by increasing the alcohol content to match that of the wine fermented from the high sugar must. Trained TCATA panelists (n=13) evaluated these treatments, with raw data were standardized using total evaluation duration for each evaluation to create a percentage of finish duration. Evaluation percentages were then segmented into thirds (beginning, middle, and end) so as to glean temporal information while maintaining large enough segments to capture what the panel as a whole perceived over the course of the finish. Results indicated that the finish of the high ethanol treatments (High and Low-to-high) lasted longer (~12 sec) than that of the low ethanol treatment (p 0.05). Cochran’s Q test was run on each term in each segment of the finish duration; differences amongst treatments were detected within each segment (p 0.05) Pairwise tests showed the High and Low-to-high was more described by astringency, heat/ethanol burn, bitterness, dark fruit, and spices while the Low was more characterized by sourness, red fruit, and green flavours (p 0.05). Principal Component Analysis on the data covariance matrix supported these results. This study demonstrates clearly the impact of ethanol on wine finish, and by extension wine quality, with obvious implications to winemakers responsible for wine processing decisions involving alcohol management.
Baker, A. K., Castura, J. C., & Ross, C. F. (2015). Temporal check-all-that-apply characterization of wine finish. 11th Pangborn Sensory Science Symposium. 23-27 August. Gothenburg, Sweden.