Can a certain concentration of rotundone be undesirable in Duras red wine? A study to estimate a consumer rejection threshold for the pepper aroma compound

Background and Aims Rotundone is responsible for peppery aroma in wine. This note is not appreciated by all consumers, which indicates that rotundone might be considered as a taint above a certain concentration. The current study aimed at determining a consumer rejection threshold for rotundone in Duras red wine. Methods and Results Consumers (n = 62) received pairs of samples consisting of a base wine and the base wine spiked with an ascending concentration of rotundone and were asked to indicate which sample they preferred. Anosmic respondents detected through triangle tests represented 31% of the panellists. For these panellists, the wine spiked at the lowest concentration was significantly rejected suggesting that rotundone might induce a trigeminal sensation and/or is involved in molecular mechanisms of flavour reduction. For remaining panellists, we were not able to determine any consumer rejection threshold. We identified three clusters of consumer profiles. The first cluster preferred a moderate concentration of rotundone and rejected a high concentration. The second cluster, mainly composed of young consumers, preferred the Control. The last group appreciated peppery wines especially at high concentration. Conclusions The response of consumers to rotundone is complex, and peppery notes are perceived positively or in a neutral manner by most consumers with the exception of young panellists. Significance of the Study Our results may assist grape growers producing Duras and other cultivars, where rotundone makes a sensory contribution, to adapt their products to consumer profiles. They also open new fields of investigation into mechanisms involved in specific anosmia to rotundone.