Ortho‐ and Retronasal stimulations with specific food odours: Hedonic and familiarity ratings are related to chemosensory pleasure scale (CPS) scores

Abstract

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.

Variability in odor hedonic perception: A challenge for neurosensory and behavioral research.

“…Furthermore, some authors show no significant difference between the two pathways for lavender, chocolate, farnesol, and butanol odors (Hummel & Heilmann, 2008; Small et al, 2005). Recently, no difference in odor hedonic ratings was found between ortho- and retronasal routes for nine food odors (Bontempi et al, 2023). However, the results of this study showed differences when considering the total score of the Chemosensory Pleasure Scale (Zhao et al, 2019): Participants with a high total score on the Chemosensory Pleasure Scale rated food odors as more pleasant than those with a low total score, and this difference was significant for retronasal stimulation.…”

Enhancing Odor Analysis with Gas Chromatography–Olfactometry (GC-O): Recent Breakthroughs and Challenges

“…Both orthonasal and retronasal olfaction are essential for human sensory experience, as they enable the perception of a wide range of aromatic compounds that influence the hedonic and cognitive evaluation of the sensory qualities of various substances. 32,33 The human olfactory system has an impressive ability to detect and recognize odors at extremely low concentrations. Certain potent odorants may be easily identified by the human nose even at parts per billion (ppb) or parts per trillion (ppt) levels.…”

“…Factors such as age, gender, genetics, exposure history, and personal experiences can influence an individual's sensory threshold. 32,33 Understanding human perception of odors provides the foundation for advanced analytical techniques such as GC-O analysis.…”

“…This pathway contributes to the flavor perception of the ingested substances. Both orthonasal and retronasal olfaction are essential for human sensory experience, as they enable the perception of a wide range of aromatic compounds that influence the hedonic and cognitive evaluation of the sensory qualities of various substances. , …”

“…Sensory thresholds, which represent the lowest concentration at which an odor becomes perceptible, vary significantly among individuals. Factors such as age, gender, genetics, exposure history, and personal experiences can influence an individual’s sensory threshold. , Understanding human perception of odors provides the foundation for advanced analytical techniques such as GC-O analysis.…”