Search

Odors and aromas perceived in food and in the environment result from the processing of complex chemical mixtures of volatile compounds that should be efficiently processed by the olfactory system. It is known for decades that this processing generates perceptual interactions, such as masking, synergy, or perceptual blending, which contribute to elaborating a synthetic brain representation of the chemical information. Nevertheless, the perceptual processes underlying these interactions are still poorly known. In this project, we set out a multidisciplinary approach to identify the characteristics of odorants and olfactory receptors (ORs) that could support perceptual interactions. We hypothesized that odorants involved in interactions at the peripheral level should share common structural characteristics to allow the activation of a common set of ORs. First, using an RNA-seq approach in mice, we identified the ORs responding to either single odorants or mixtures exhibiting specific perceptual interactions. Then, we confirmed that the target ORs responded to odorants in an in vitro cellular system and that the expected perceptual interactions occurred between the odorants at the olfactory periphery, through EOG recordings on mice’s olfactory mucosa, but also through sensory evaluation in humans. Additionally, a computational study revealed common molecular features between the odorants involved in interactions. When combined, all the results highlight that perceptual interactions such as masking could rise from competition between odorants at the OR level, but that other interactions such as perceptual blending most likely originate from more central integrative brain processing.

The Odour-Induced Taste Enhancement (OITE) phenomenon allows, by addition of odorants in food or beverages, to enhance the perception of taste. To the best of our knowledge, only Proserpio et al. [1] studied OITE in obese people. Interestingly, in this study, the addition of butter aroma in custard dessert produced OITE only in obese and not in normal-weight people. Here we extended this result by comparing Odour-Induced Sweetness and Saltiness Enhancement in normal-weight and obese peoples using a ranking task on beverages. Forty-three normal weight (NW: 20< BMI< 25kg/m²) and 28 obese participants (OB: BMI> 30kg/m²) took part in the sensory evaluation of 2 sweet solutions and 2 salty solutions. The sweet base solutions were apple juice (Aj) and water and the added odorant was vanillin. The salty base solutions were a green-pea soup and water and the added odorant was a bacon aroma. For the ranking task, three additional solutions with increasing concentrations of either sucrose or sodium chloride (S1 to S3) were prepared for each base. Each solution was tested in a dedicated ranking trial. Subjects received four bottles in a given trial, the three sweet or salty concentrations of the base solution (e.g. AjS1, AjS2, and AjS3) and one of the odorant-added solutions (e.g. AjS1+vanillin). Participants had to rank the 4 bottles according to sweetness or saltiness intensity. The results showed that OITE occurred for all the solutions but differently according to the group and the complexity of the beverage base. In the sweet complex beverage (Aj), only OB perceived a sweet taste enhancement whereas in the green-pea soup OB and NW perceived a salty taste enhancement. OB and NW participants ranked the water-based solutions in a similar way, independently of taste, but with a lower effect size compared with the complex solutions. The highest OITE was observed for the sweet Aj+vanillin and the salty Wsa+bacon samples (sweetness and saltiness increased by at least 50% and 75%, respectively) in OB. To conclude, we showed that the OITE phenomenon significantly differed between NW and OB. Only OB experienced OITE in the sweet complex beverage, while OB and NW experienced OITE in the salty soup. Both groups experienced OITE in the sweet water solutions but with a lower effect size compared with the complex solution (Aj). Our results also demonstrated that the ranking task is efficient to assess OITE and to highlight OITE differences between groups and solutions.

International audience; The cerebral activity associated with attentional processes may differ between individuals with different weight statuses in the presence of food stimuli (e.g. odours, pictures). The objective of the present study was to test the influence of non-attentively perceived food odours on the cerebral activity underlying the processing of food pictures, in normal-weight, overweight, and obese adults. To do so, we used an implicit olfactory priming paradigm with a pear odour and a pound cake odour as primes, respectively priming sweet low-energy-density foods and sweet high-energy-density foods. Event-related potentials were recorded while the participants passively watched pictures of sweet low- and high-energy-density foods, under the two priming conditions plus an odourless control condition. The amplitude of the P100 and the P200 peaks were measured. The results suggest that the cerebral activity underlying the processing of food cues differs depending on weight status, from early and non-conscious stages of attentional processing.

National audience

La nécessité de disposer d’une offre alimentaire qui permette aux consommateurs de suivre les recommandations nutritionnelles des organisations de santé publique est toujours aussi pressante. Pour cela il est nécessaire de développer des stratégies permettant de compenser les pertes organoleptiques associées à la réduction des teneurs en matières grasses et en sel et/ou sucre. Plusieurs stratégies sont déjà mises en oeuvre et/ou encore à l’étude. Notre laboratoire concentre ses travaux sur les stratégies s’appuyant sur les interactions multimodales, notamment entre les saveurs et les arômes. Dans cet article, nous présentons des études récentes qui nous ont permis de démontrer que certains arômes ont la capacité de renforcer la perception des saveurs salée et sucrée, mais aussi la perception de la matière grasse. Nous avons développé des méthodologies permettant de sélectionner, parmi les arômes naturellement présents dans un aliment, ceux qui sont associés à ces saveurs ; puis de tester ceux qui ont la capacité de compenser des réductions en gras, sel ou sucre pouvant aller jusqu’à 30%. Des réductions plus importantes peuvent être compensées sensoriellement en combinant cette stratégie avec d’autres stratégies comme la substitution partielle ou la distribution optimisée des composés gustatifs., The need for food supply that helps consumers to follow nutritional recommendations of public health organizations is still pressing. Therefore, it is required to develop strategies to compensate sensory losses associated with the decrease in the levels of fat and salt and/or sugar. Several strategies are already implemented and/or are still under study within research projects. Our laboratory focuses on strategies that aim leveraging multisensory interactions such as aroma-taste interactions. In this paper, we present recent studies that have allowed us to show that certain aromas can enhance the perception of salty and sweet taste, and the perception of fat content. We have developed methodologies which help selecting the aromas, naturally present in a food, that are associated to these tastes; then to test those aromas that have the ability to compensate for reductions in fat, salt or sugar up to 30%. Higher reductions can be targeted by combining this aroma-based strategy with others such as the partial substitution or the distribution optimisation of flavor-active compounds.

National audience; The need for food supply that helps consumers to follow nutritional recommendations of public health organizations is still pressing. Therefore, it is required to develop strategies to compensate sensory losses associated with the decrease in the levels of fat and salt and/or sugar. Several strategies are already implemented and/or are still under study within research projects. Our laboratory focuses on strategies that aim leveraging multisensory interactions such as aroma-taste interactions. In this paper, we present recent studies that have allowed us to show that certain aromas can enhance the perception of salty and sweet taste, and the perception of fat content. We have developed methodologies which help selecting the aromas, naturally present in a food, that are associated to these tastes; then to test those aromas that have the ability to compensate for reductions in fat, salt or sugar up to 30%. Higher reductions can be targeted by combining this aroma-based strategy with others such as the partial substitution or the distribution optimisation of flavor-active compounds.; La nécessité de disposer d’une offre alimentaire qui permette aux consommateurs de suivre les recommandations nutritionnelles des organisations de santé publique est toujours aussi pressante. Pour cela il est nécessaire de développer des stratégies permettant de compenser les pertes organoleptiques associées à la réduction des teneurs en matières grasses et en sel et/ou sucre. Plusieurs stratégies sont déjà mises en oeuvre et/ou encore à l’étude. Notre laboratoire concentre ses travaux sur les stratégies s’appuyant sur les interactions multimodales, notamment entre les saveurs et les arômes. Dans cet article, nous présentons des études récentes qui nous ont permis de démontrer que certains arômes ont la capacité de renforcer la perception des saveurs salée et sucrée, mais aussi la perception de la matière grasse. Nous avons développé des méthodologies permettant de sélectionner, parmi les arômes naturellement présents dans un aliment, ceux qui sont associés à ces saveurs ; puis de tester ceux qui ont la capacité de compenser des réductions en gras, sel ou sucre pouvant aller jusqu’à 30%. Des réductions plus importantes peuvent être compensées sensoriellement en combinant cette stratégie avec d’autres stratégies comme la substitution partielle ou la distribution optimisée des composés gustatifs.

Le Centre des Sciences du Goût et de l'Alimentation (CSGA) célèbre la Semaine du Goût en ouvrant ses portes au grand public dijonnais. Plusieurs animations sont prévues : dégustation, parcours sensoriel, stands, exposition, vidéos... En collaboration avec la Mission Culture Scientifique de l’uB et l’association EveilOGoût, les activités suivantes seront proposées :[br/] Atelier 1 : Nouveaux produits adaptés à l’alimentation des seniors. Dégustation de produits développés pour les seniors dans le cadre de projets de recherche. Discussion avec les chercheurs impliqués dans ces études.[br/] Atelier 2 : Parcours sensoriel dans une région de France. Dégustations de produits. L’objectif de cet atelier est de prendre conscience de l’importance de nos 5 sens lorsque nous dégustons un produit. Cet atelier sera animé par l’association EveilOGoût.[br/] Des stands « objets de recherche » : plusieurs chercheurs du CSGA présenteront leurs travaux et échangeront avec le public. Un espace d’exposition où seront présentés des résultats de recherche marquants obtenus ces dernières années au CSGA.[br/] Projections de vidéos.

Short paper dans conférence.; International audience; The olfactory dimension of food flavour is critical to the food identity and typicality. Food odour and aroma result from the processing of complex mixtures of volatile compounds activating the sense of smell. The perceptual properties of odour mixtures have been explored from both the aroma analysis point of view and the psychophysical point of view, thus revealing perceptual effects such as masking, synergy, or perceptual blending. However, considering odorants separately, the classical aroma analysis approach misses the central role of perceptual integration in odour mixture processing. Therefore, the challenge of food flavour analysis is now to integrate the mechanisms of complex odorant mixtures perception. Here, we briefly review recombination strategies and tools that are already available to go one step forward and consider not only keyodorants but also key-associations involved in overall flavour perception.

The olfactory dimension of food flavour is critical to the food identity and typicality. Food odour and aroma result from the processing of complex mixtures of volatile compounds activating the sense of smell. The perceptual properties of odour mixtures have been explored from both the aroma analysis point of view and the psychophysical point of view, thus revealing perceptual effects such as masking, synergy, or perceptual blending. However, considering odorants separately, the classical aroma analysis approach misses the central role of perceptual integration in odour mixture processing. Therefore, the challenge of food flavour analysis is now to integrate the mechanisms of complex odorant mixtures perception. Here, we briefly review recombination strategies and tools that are already available to go one step forward and consider not only keyodorants but also key-associations involved in overall flavour perception.

Le Centre des Sciences du Goût et de l'Alimentation (CSGA) célèbre la Semaine du Goût avec le grand public dijonnais ! Au programme : la projection au Jardin des Sciences d'un film suivi d'un débat avec les chercheurs, puis une journée porte ouverte dans les locaux du CSGA sur le campus.

absent

Evidence of peripheral olfactory adaptation: Electrophysiological recordings of the human olfactory epithelium. 17. international symposium on Olfaction and taste (ISOT)

The first step of odor perception is an interaction between odorants and olfactory receptors [1]. The corresponding transduced olfactory signals, conveyed by olfactory sensory neurons, are then processed by the brain [2]. It is now accepted that the main strategy used to discriminate thousands of odors results from a combinatorial coding [3]. Moreover, odors perceived in our environment are mainly the result of mixtures of odorants; however, the specific mechanisms involved in their processing remain poorly understood [4]. In previous studies performed in the CSGA of Dijon [5-7], we investigated the perception of a mixture of 6 components: vanillin, oxanone (4-(4-hydroxyphenyl)butan-2-one), isoamyl acetate, beta-ionone, ethyl acetate, and beta-damascenone. We have shown that, at specific proportions, this mixture is configurally processed and perceived as different from its components and carries the specific odor of red cordial (blending RC mixture). Assuming that combinations of activated ORs encode odor qualities [8, 9], we used Common Feature Pharmacophore Generation protocol (Discovery Studio 4.1, Biovia) to generate pharmacophore hypotheses [10]. The purpose is to identify whether molecular characteristics may be common to the molecules of the mixture, which would highlight that configural perception is linked to overlapping patterns of OR. In our study, the pharmacophoric features considered are hydrogen bond acceptors (HBA) and hydrophobic regions (HY); the maximum number of generated hypothesis for each run was set to 10. The pharmacophores obtained by using the six molecules are built up of one HY and one HBA; this seems not very meaningful despite a satisfactory alignment of the molecular structures. Besides, we generated the pharmacophores for each molecule using its conformers as individual molecules (maximum 250 conformers in energy range 20kcal/mol). By comparing the pharmacophores two by two, we identified a pair of molecules, vanillin and oxanone, whose pharmacophores possess some common characteristics 2 HBA located 8 Å from each other and 1 HY between those two. Interestingly, the basis of RC consists of a mixture of vanilla and red berries, while vanillin and oxanone carry respectively the notes “vanilla” and “raspberry”. These results suggest that a similar binding site could exist for at least the two molecules likely sharing key odor notes of the blending mixture. It thus supports the hypothesis that molecules involved in a mixture that elicits an emergent odor recognize a c ommon set of ORs. Bibliography [1] L. Buck, R. Axel Cell 65 (1991) 175-187. [2] D.A. Wilson, R.M. Sullivan Neuron 72 (2011) 506-519. [3] B. Malnic, J. Hirono, et al. Cell 96 (1999) 713-723. [4] T. Thomas-Danguin, C. Sinding, et al. Front. Psychol. 5 (2014) 504. [5] E. Le Berre, E. Jarmuzek, et al. Chemosens. Percept. 3 (2010) 156-166. [6] C. Sinding, T. Thomas-Danguin, et al. PLoS One 8 (2013) e53534. [7] S. Romagny, T. Thomas-Danguin, et al. Physiol. Behav. 142 (2015) 161-169. [8] Y. Furudono, Y. Sone, et al. Chem. Senses 34 (2009) 151-158. [9] H. Saito, Q. Chi, et al. Sci. Signal. 2 (2009) 1-14. [10] O.O. Clement, A. Mehl, HipHop: Pharmacophore Based on Multiple Common-Feature Alignments, in: O.F. Güner (Ed.) Pharmacophore perception, Development and Use in Drug Design, International University Line, La Jolla, 2000, pp. 69-84.