Odor hedonic evaluation (pleasant/unpleasant) is considered as the first and one of the most prominent dimension in odor perception. While sex differences in human olfaction have been extensively explored, gender effect in hedonic perception appears to be less considered. However, a number of studies have included comparisons between men and women, using different types of measurements (psychophysical, psychophysiological,…). This overview presents experimental works with non-specific and body odors separately presented as well as experimental studies comparing healthy participants vs patients with psychiatric disorders. Contrary to sensitivity, identification or discrimination, the overall literature tends to prove that no so clear differences occur in odor hedonic judgment between men and women. On the whole, gender effect appears more marked for body than non-specific odors and is almost never reported in psychiatric diseases. These findings are discussed in relation to the processes classically implied in pleasantness rating and emotional processes.

Volatile compounds can reach olfactory epithelium though the nose (orthonasal olfaction) or the mouth (retronasal olfaction). Although differences have been found between these two pathways in terms of odour sensitivity and identification, few studies have examined ortho‐ and retronasal differences taking into consideration the three main dimensions of olfactory perception (i.e. hedonicity, intensity and familiarity). Olfactory perception, and particularly odour hedonic perception, is influenced by several factors such as sex or age. Another variability factor worth considering, especially regarding food‐related odours, is the ability to experience pleasure simulated by smell or taste, which can be measured with the Chemosensory Pleasure Scale (CPS). Thus, the aims of this study were (1) to compare odour sensory ratings in response to ortho‐ and retronasal presentation and (2) to examine the relationship between CPS scores and odour sensory ratings in ortho‐ and retronasal pathways. Participants rated ten food odours in ortho‐ and retronasal conditions using visual analogue scales and were divided into two subgroups based on the median CPS score (CPS+ and CPS− groups). Results revealed similar sensory responses to food odours between ortho‐ and retronasal pathways for the three main dimensions of olfactory perception. Interestingly, when CPS scores were considered, clear differences in odour familiarity and hedonicity were shown, particularly for the retronasal pathway (i.e. odours were perceived as more pleasant and more familiar in CPS+ group than in CPS− group). Overall, these findings suggest that differences in odour perception between ortho‐and retronasal pathways may be related to specific individual characteristics such as chemosensory hedonic capacity.

Odor hedonic perception (pleasant/unpleasant character) is considered as the first and one of the most prominent dimensions in olfaction and is known to depend on several parameters. Among them, the relation between the odorant concentration and the hedonic estimation has been widely studied. However, few studies have considered odor hedonic ratings (OHR) in relation to individual detection thresholds (IDT). Thus, the aim of this study was to determine olfactory detection thresholds and to describe hedonic rating variations from individual thresholds to higher concentrations. IDT were performed for two pleasant (apple and jasmine) and two unpleasant (durian and trimethylamine) odorant stimuli. The experimenter presented one by one in a randomized order, the different odorant concentrations above IDT. Participants rated odor hedonic valence of these stimuli on a visual analog scale. Results showed, except for trimethylamine, the same relationship between hedonic ratings and stimulus concentration, i.e., an increase of pleasantness (apple and jasmine)/unpleasantness (durian) ratings at low and middle concentrations followed by a plateau at high concentrations. Correlations between OHR and concentrations as well as between OHR and threshold steps were always significant. Moreover, comparisons between both conditions showed that the correlation coefficient was significantly higher for trimethylamine (and a trend for apple) when IDTs were considered, while no difference was found for jasmine and durian. Overall, results suggested that the relationship between OHR and IDT is odor specific. These findings contribute to explain the large variability of the hedonic tone (i.e., weakly vs. very pleasant, weakly vs. very unpleasant) at specific concentration in the general population and could serve future research in this field (e.g., olfactory preferences in nutrition studies, anhedonia in psychiatric disorders…).

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Odor hedonic estimation (pleasant/unpleasant) is considered the first and one of the most important dimensions in odor perception. Although there are several published scales that rate odor hedonicity, most of them use odorants that induce biases related to stimulus properties or test conditions and make difficult clinical or industrial applications. Thus, this study aimed to propose a model of odor hedonic profile (OHP) based on 14 items related to everyday odors without stimulus. The OHP is a self-rating tool based on the hedonic estimate representation and allows the determination of specific profiles, i.e., “conservative,” “neutral,” “liberal,” “negative olfactory alliesthesia,” and “positive olfactory alliesthesia.” It can be useful in different contexts (e.g., food studies) and general pathologies (e.g., eating disorders) or pathologies with mood/emotional disturbances (e.g., depression).