Brain representation of food in obese and normal-weight populations – AROMA

Multiple disciplines are involved in this project, including food science, sensory evaluation, and neuroscience.

The sensory evaluation approach is utilized to characterize perceptual differences between the two populations of interest, allowing us to target simple food models that can be tested in brain exploration experiments.

Regarding brain exploration techniques, we employ electroencephalography (EEG), which enables real-time recording of brain activity with a resolution on the order of milliseconds during beverage tasting. Analysis of these data helps us understand the organization of brain processing of flavor and compare sensory and cognitive processes between the two populations of interest.

Another technique utilized is structural and functional magnetic resonance imaging (MRI). Structural MRI allows mapping of different brain regions in each participant and measuring gray matter density. Functional MRI, on the other hand, measures the activity of these brain regions during the consumption of sweet or salty beverages, with or without a reinforcing aroma.

By combining these three approaches, we will gain a better understanding of the brain mechanisms involved in flavor processing, as well as the relative importance of different brain structures in taste enhancement by aroma.

We have developed a sensory evaluation method based on the ranking task, specifically adapted to characterize taste enhancement by aroma in our two groups of interest. This approach enables us to analyze, with precision and comparability, how odor influences taste perception in both populations.

We have performed data recordings using MRI and EEG, and we are currently in the process of analyzing this data. However, due to the simultaneous nature of recording two types of sensory modalities (olfaction and gustation), which involve distinct receptor networks and brain regions, EEG recordings may exhibit some level of noise, although they remain interpretable. Therefore, we intend to develop specific methods to increase the signal-to-noise ratio and improve the quality of EEG recordings specifically for experiments on flavor perception.

Aveline C, Thomas-Danguin T, Sinding C. 2023. Ranking task vs. intensity scales, what is the best method to evaluate odor-induced taste enhancement? Journal of Sensory Studies

The formulation of healthy food acceptable by the consumer is penalized because flavor perception, which is built in our brain through integratory processes and which mainly drives food acceptability, is so far still unpredictable. In AROMA project I will investigate one strategy of sugar/salt reduction using aroma (OITE) -with a focus on a specific population (obese vs normal-weight), to unravel the key brain mechanisms of mental representation of food (flavor perception). This system will be investigated with a set of complementary brain imaging technics and a multidisciplinary approach: from food model formulation to brain imaging, including sensory evaluation. AROMA will provide valuable insights and new results: (1) on the key mechanisms of flavor perception through the prism of obesity and (2) on the validation of OITE as a strategy to reduce salt and sugar in food for a variety of consumers and (3) on proofed method in Neurosciences to study OITE.