Individual Differences in Thresholds and Consumer Preferences for Rotundone Added to Red Wine.

Rotundone is an aromatic compound found in the skin of some grapes (e.g., Shiraz, Noiret) that contributes peppery notes to wines made with these varieties. There may be a specific anosmia for rotundone, as some individuals are unable to detect it even at high concentrations, despite otherwise normal olfaction. This may affect perception of and preference for rotundone-containing wines. Here, we report rotundone detection thresholds (orthonasal n = 56; retronasal n = 53) and rejection thresholds (n = 86) in red wine for a convenience sample of non-expert consumers in Pennsylvania. Focus groups were conducted to better understand consumer attitudes and preferences for rotundone. Ortho- and retronasal detection thresholds were nearly identical (140 v. 146 ng/L). Roughly 40% of our sample was anosmic to rotundone, extending evidence for a specific anosmia to a North American cohort. As ortho- and retronasal thresholds were extremely similar, future work on rotundone can rely on orthonasal assessment. In our participants, added rotundone was generally disliked, and in focus groups, the concept of a 'peppery' wine was not appealing. Winemakers need to carefully consider biological and attitudinal segmentation when making and marketing peppery wines. Further work is needed to identify the genetic basis for this anosmia.

Vanillin modifies affective responses to but not burning sensations from ethanol in mixtures.

Vanillin may modulate perception of noxious oral stimuli via TRP receptor interactions; separately, vanillin has also been shown to have top-down influences on flavor perception. Here, we ask whether added vanillin decreases the perceived burn of ethanol either via peripheral or cognitive mechanisms. Participants rated the burn of ethanol with 0, 16, and 160 ppm vanillin. In studies 1 (n = 102) and 2 (n = 82), participants wore nose clips and rated the burn of 8% and 16% ethanol (study 1) or 32% and 48% ethanol (study 2). In study 3 (n = 65), participants were able to breathe freely and rated liking and perceptual qualities of 8% and 32% ethanol at each vanillin level. Vanillin showed no significant effect on ratings of burn or smoothness, but did increase perceived sweetness (p < .001) and liking (p = .004) in study 3. These data suggest vanillin does not modulate ethanol burn via TRP receptor mediated interactions, but may shift hedonic responses to ethanol via top-down processes.

Smelling is Telling: Human Olfactory Cues Influence Social Judgments in Semi-Realistic Interactions.

How does a person's smell affect others' impressions of them? Most body odor research asks perceivers to make social judgments based on armpit sweat without perfume or deodorant, presented on t-shirts. Yet, in real life, perceivers encounter fragranced body odor, on whole bodies. Our "raters" wore blindfolds and earplugs and repeatedly smelled same-sex "donors" in live interactions. In one condition, donors wore their normal deodorant and perfume ("diplomatic" odor) while in the other condition, donors were asked to avoid all outside fragrance influences ("natural" odor). We assessed the reliability of social judgments based on such live interactions, and the relationships between live judgments and traditional t-shirt based judgments, and between natural- and diplomatic odor-based judgments. Raters' repeated live social judgments (e.g., friendliness, likeability) were highly consistent for both diplomatic and natural odor, and converged with judgments based on t-shirts. However, social judgments based on natural odor did not consistently predict social judgments based on diplomatic odor, suggesting that natural and diplomatic body odor may convey different types of social information. Our results provide evidence that individuals can perceive reliable, meaningful social olfactory signals from whole bodies, at social distances, regardless of the presence or absence of perfume. Importantly, however, the social value of these signals is modified by the addition of exogenous fragrances. Further, our focus on judgments in same-sex dyads suggests that these olfactory cues hold social value in non-mating contexts. We suggest that future research employ more ecologically relevant methods.