Investigating Fruitiness Perception in Red and White Wines

This report details activities that occurred from February 2017 – January 2018. We have had a very exciting accomplishment with the adaptation of a chemometric method that can calculate chemical interactions resulting in specific sensory perceptions. This method, fuzzy set qualitative comparative analysis (fsQCA), overcomes the issues with traditional correlation analysis that made determining aroma chemical interactions very difficult. To date we have investigated 43 different compound combinations and their impact to fruit aroma in Pinot noir wine. By applying fsQCA we have found 15 compound sets that result in red fruit aroma in Pinot noir wine and 2 compound sets that result in dark fruit aroma in Pinot noir wine. The necessary and sufficient conditions found in these sets are supported by other work, but our results are the first to show the multiple combinations of compounds that can result in specific fruity aromas. We have also investigated 20 compound combinations for fruitiness in white wine. We have yet to apply fsQCA to this data but in using more traditional correlation analysis (canonical variate analysis) we find that terpenes and certain esters are important for “stonefruit” and “citrus” aromas and thiols are the drivers of more “grapefruit” aromas. In our last year we aim to continue investigating different compounds in both red and white. We are also incorporating nonvolatile factors into the analysis. In red wine we are investigating the effect of phenolic composition on fruitiness perception and in white
wine we are changing the residual sugar concentration to determine its impact on fruity perception in white wines. We will also apply fsQCA analysis to the data from our white wine sensory panels, determining the necessary and sufficient conditions for specific fruitiness in white wines.