Crossed approaches to experimental economics and sensory analysis regarding noble rot sweet wines perception

Abstract

Noble rot sweet wines are reputed wines, traditionally elaborated according to a singular vinification process involving the harvesting of overripe grapes under the action of the ascomycete fungus Botrytis cinerea. These exceptional wines for the richness of their aromatic palette, evoking honey, dried fruits and citrus nuances often present a strong aging potential. Thus, several research works have contributed for the past 10 years to characterize their typical aromas and identify key volatile compounds as well as the parameters of their formation. However, although having high reputation and still being considered as high quality wines, they are facing a consumer crisis for the past 15 years.

Experiments have also been conducted to deepen the links between their composition (aromatic component, sugar content) and their sensory perception by an expert panel and a panel consumers (130 persons) in a context of experimental economics studies. In details, sixteen wines from various Bordeaux sweet wines denominations of appellation origin from 2015 vintage were initially submitted to a panel of professionals, oenologists and researchers to assess their typicality level (aromatic component, complexity, balance sweetness / acidity). This preliminary study has allowed to retain 4 wines representing 2 models of Bordeaux sweet wines, i.e. those considered with the best exemplary notes, in terms of aromatic profile and taste equilibrium, having a sugar content close to one hundred g/L and those considered as less typical, although fruity and having a sugar content close to 70 g/L. Chromatographic analysis on the main volatile markers of the aromatic component of the noble rot sweet wines confirmed a generally higher level of abundance of these compounds (lactones, furanones) in the wines with the best exemplary ratings. These 4 wines were then submitted to a panel of consumers. Among the highlights of this study, it is clear that consumers did not use as the first criterion the level of sugar concentration of wines but they recognized the originality of their aromatic component, including among other criteria naming information of controlled origin as well as on noble rot. This study encourage to involve consumers in order to refine the choices of winemakers in the definition of wine profiles.