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The Republic of Djibouti is a small country in the Horn of Africa and, as in most developing countries, rain gauges are sparse and data are scarce. This study aims to report on the reliability of gridded precipitation datasets (P datasets) across the Republic of Djibouti through direct comparisons with rain gauge measurements from the annual to the daily time scales. Our specific objective is to be able to use such products in the context of hydrological modeling at a daily time step. Given the scarcity of available data in the Republic of Djibouti, our study was carried out on two time windows (1980–1990 and 2008–2013) and two gauge networks with different spatial resolutions: the southeast of the Republic of Djibouti (5000 km2) and the Ambouli catchment (794 km2), which drains the city of Djibouti. The reliability of these products is analyzed with quantitative metrics and categorical metrics, exclusively at a daily time step for the latter. The performance of the P datasets degrades from the annual time scale to the daily time scale. Even though the same products exhibit the best performance at the various time scales, the performance of most of the products differs from one spatial scale to another. Our results demonstrate the importance of the temporal and spatial windows, as the same products can perform differently according to the scale. For all the spatiotemporal scales, the most reliable product is MSWEP v.2.2. This P dataset is derived from a combination of satellite products (multiple sensors such as infrared and passive microwave), reanalysis products, and rain gauge observations. A strong discrepancy between rain gauge observations and P datasets is revealed according to the categorical metric at a daily time step. The analysis of rainfall events triggering runoff, using a 10 mm rainfall threshold, showed that the most efficient products were unable to accurately detect such events at a daily time step, with a significant underestimation of rainfall events higher than 10 mm. None of these products, even the most reliable, can be used for a calibration/validation of a hydrological model at a daily time step.

The Republic of Djibouti is a small country in the Horn of Africa and, as in most developing countries, rain gauges are sparse and data are scarce. This study aims to report on the reliability of gridded precipitation datasets (P datasets) across the Republic of Djibouti through direct comparisons with rain gauge measurements from the annual to the daily time scales. Our specific objective is to be able to use such products in the context of hydrological modeling at a daily time step. Given the scarcity of available data in the Republic of Djibouti, our study was carried out on two time windows (1980-1990 and 2008-2013) and two gauge networks with different spatial resolutions: the southeast of the Republic of Djibouti (5000 km2) and the Ambouli catchment (794 km2), which drains the city of Djibouti. The reliability of these products is analyzed with quantitative metrics and categorical metrics, exclusively at a daily time step for the latter. The performance of the P datasets degrades from the annual time scale to the daily time scale. Even though the same products exhibit the best performance at the various time scales, the performance of most of the products differs from one spatial scale to another. Our results demonstrate the importance of the temporal and spatial windows, as the same products can perform differently according to the scale. For all the spatiotemporal scales, the most reliable product is MSWEP v.2.2. This P dataset is derived from a combination of satellite products (multiple sensors such as infrared and passive microwave), reanalysis products, and rain gauge observations. A strong discrepancy between rain gauge observations and P datasets is revealed according to the categorical metric at a daily time step. The analysis of rainfall events triggering runoff, using a 10 mm rainfall threshold showed that the most efficient products were unable to accurately detect such events at a daily time step, with a significant underestimation of rainfall events higher than 10 mm. None of these products, even the most reliable, can be used for a calibration/validation of a hydrological model at a daily time step.

The wadi Ambouli is at the origin of rare and severe flash floods with increasing frequency in recent years. These floods are responsible for a lot of damage including human lives and good losses. Moreover, the aquifer located in the south-eastern part of the wadi Ambouli watershed (794 km²) is essential as the main source of drinking water for the city of Djibouti. Therefore, knowledge and prevention of flows events are of primary relevance for the development and flood prevention of the city of Djibouti neasted downstream to the wadi Ambouli.Within the framework of the management of the urban expansion of the city, it is necessary, in the long term, to set up a hydrological model in order to model the flow and flood processes and to better understand the groundwater/surface water dynamics. A special focus is needed toward the extreme events.To overcome the few rainfall available data, remote sensing techniques have been used to provide more representative information on rainfall spatio-temporal distributions. We present here a comparative study of rainfall data from 15 satellite products with those from rain gauge stations located in the wadi Ambouli watershed.The analysis is conducted on various time steps, annual, monthly and daily, at the spatial scale from the Ambouli watershed (794 km²) to the point scale (comparison of point rainfall station and satellite grid). The comparisons of time series are based on the correlation coefficient r with the corresponding p-value and the Kling Gupta Efficiency (KGE) criterion.The first results at annual and monthly time steps show that 5 satellite products present a high correlation coefficient and KGE with ground rainfall data (EWEMBI, GPCC, JRA_55_Adj, MSWEP and WFDEI_GPCC). For the Djibouti Aerodrome station, which is the one with the longest temporal data, the satellite products EWEMBI, JRA_55_Adj, and WFDEI_GPCC provide the best estimates of rainfall depth (annual scale). The MSWEP product (with r = 0.76) underestimates the annual rainfall over almost the entire study period.

In recent decades, floods are recurrent and intensifying in African major cities. Every year, rains cause material damage and human losses, in Abidjan (Ivory Coast). This study contributes to the characterization of the rain hazard in the District of Abidjan. The available data are made up of daily rainfall from a historical station "Abidjan airport" (1961-2014) and an academic network of 21 rain gauges progressively implemented in Abidjan since 2016. The annual rainfall observed from 2016 to 2021 on the sites of this network are representative of the interannual variability of the historical station. An analysis (date of occurrence, rainfall depth, mean intensity of wet days and number of rainy days) on the Highest Cumulative Rainfall Periods (HCRP:15, 30 and 60 days) is conducted on the long-term station, in order to characterize the periods of highest risk of flooding occurrence during the long and short rainy seasons. Date of HCRP occurrence during long rainy season is relatively stable over time. It tends to occur later in the short rainy season. In recent years, the mean intensity of wet days remains steady despite intensifying flooding.The current network of rain gauges permits to discuss the spatial variability of the date of HCRP over Abidjan. It can be seen that the date of HCRP occurrence in the long rainy season is uniform across the area of Abidjan, whereas it appears more variable during the short rainy season. At the daily scale and for 60 days- HCRP of the two rainy seasons, the extreme quantiles are determined and their evolution analysed over the historical period. With the current network, the experimental variograms of extreme rainfalls allows to evaluate their spatial extensions according to the rainy season.Beyond this analysis of daily rainfall, the next step will consist in the characterisation of rainfall events at the sub-daily scale in order to update the intensity-duration-frequency curves and the design storm, which is a prerequisite for a better estimation of floods and sizing of structures.

Faba bean (Vicia faba L. minor) has many interests but is characterised by off-notes (negative odours/aromas) due to volatile compounds that are promoted during seed processing. Little is known about the volatile compounds of faba bean and their contribution to its odour. The purpose of this study was to determine the volatile compound origins of air-classified fractions (flour (F), starch (S) and protein (P)) from 3 faba bean cultivars and identify the odour-active compounds. Firstly, the volatile content of the fractions was extracted by solvent-assisted flavour evaporation (SAFE) and analysed by gas chromatography-mass spectrometry (GC-MS). A total of 147 volatile compounds were detected and categorised into 12 chemical classes. The P fractions had many volatile compounds from free fatty acid (FFA) oxidation and a higher lipoxygenase (LOX) activity. The volatile content suggested that cultivar 1 (C1) was confronted with a biotic stress at field whereas cultivar 2 (C2), richer in molecules from amino acid (AA) degradation, was contaminated by microorganisms in the field. Secondly, 35 odour-active compounds (OACs) were identified by GC-olfactometry (GC-O) and 12 odour-classes were used to describe the faba bean odours. The P fractions had higher detection frequency (DF) than the S and F fractions. P2 had a more complex odour profile due to important FFA and AA degradation. This work provides a better understanding of the impact of cultivar and processing steps on the faba bean volatile content. Selection of pulse-based ingredients with low volatile compounds could improve their flavour and increase their consumption.

Les zones côtières sont sous l'influence des rejets des espaces urbains de proximité, lors d'épisodes pluvieux. Une approche pluridisciplinaire qui combine hydrologie et sociologie, s'avère indispensable pour prendre en compte les stratégies de gestion de l'espace urbain dans la modélisation physique des rejets de temps de pluie. Des entretiens semi-directifs ont été réalisés sur le territoire de Montpellier, auprès d’interlocuteurs choisis pour être représentatifs des acteurs locaux de la gestion de l’eau (élus, services techniques, services de l’état, associations, scientifiques), suivis d'un focus groupe. Les 24 entretiens ont été orientées vers la perception et les représentations de la pollution engendrée par les eaux pluviales urbaines et l'intérêt des mesures de désimperméabilisation du milieu urbain. Ils visaient à comprendre comment les acteurs locaux s’emparent de ces questions et à mesurer l’acceptation du recours aux techniques alternatives d'aménagement de l'espace urbain. La persistance de pratiques techniques lourdes -bassin de retenue- face à des pratiques douces -jardin de pluie- a été mise en évidence et comparées aux pratiques développées sur d’autres territoires. Les effets de cultures locales ou d’idées reçues ont été identifiés : la question de la qualité des eaux pluviales lors de tous les épisodes pluvieux émerge difficilement face au risque d’inondation dû au climat méditerranéen. Les entretiens plus ciblés et le groupe de discussion ont permis de mettre en évidence les blocages à la mise en place des techniques alternatives dans la zone urbaine de Montpellier. Les résultats ont permis de proposer quelques scénarii de gestion des eaux de ruissellement pluvial très classiques : mise en place de revêtements perméables sur les surfaces de type voies de circulation ou connexion des ruissellements des toitures vers des zones perméables., Coastal areas are under the influence of discharges from nearby urban spaces during rainfall events. A multidisciplinary approach that combines hydrology and sociology is essential to take into account the strategies of urban planning in the physical modeling of rainfall-runoff modeling.Semi-structured interviews were carried out in the Montpellier area, with interlocutors chosen to be representative of local stakeholders in water management (elected officials, technical services, state services, associations, scientists), followed a focus group. The 24 interviews were oriented towards the perception and representations of the pollution generated by urban runoff and the interest of measures to reduce the imperviousness of the urban environment. They aimed to understand how local stakeholders seize on these questions and to measure the acceptance of the use of alternative techniques of urban planning. The persistence of heavy technical practices - stormwater basin - against gentle practices – rain garden - has been highlighted and compared to the practices developed in other territories. The effects of local cultures or preconceived ideas have been identified: the question of the quality of rainwater during all rainfall events emerges with difficulty against of the flooding risk in Mediterranean areas. The more targeted interviews and the focus group made it possible to point out the obstacles to the implementation of alternative techniques in the urban area of Montpellier.The results made it possible to propose very conventional urban planning scenarios: installation of pervious coverings on traffic routes (or park lots) or connection of runoff from roofs to permeable areas.

Vitamins are known to generate bitterness, which may contribute to an off-taste or aftertaste for some nutritional supplements. This negative sensation can lead to a reduction in their consumption. Little is known about the bitter taste threshold and taste sensing system for the bitter taste detection of vitamins. To better understand the mechanisms involved in bitterness perception, we combined taste receptor functional assays and sensory analysis. In humans, bitter taste detection is mediated by 25 G-protein-coupled receptors belonging to the TAS2R family. First, we studied the bitterness of thirteen vitamins using a cellular-based functional taste receptor assay. We found four vitamins that can stimulate one or more TAS2Rs. For each positive molecule–receptor combination, we tested seven increasing concentrations to determine the half-maximal effective concentration (EC50) and the cellular bitter taste threshold. Second, we measured the bitter taste detection threshold for four vitamins that exhibit a strong bitter taste using a combination of ascending series and sensory difference tests. A combination of sensory and biological data can provide useful results that explain the perception of vitamin bitterness and its real contribution to the off-taste of nutritional supplements.

Aquatic ecosystems subjected to anthropic pressures are likely hotspots for emergence or dissemination of antimicrobial resistant bacteria. The city of Montpellier is located on a Mediterranean climate watershed that undergoes strong demographic pressures. The aim of the study is to explore antimicrobial resistance, particularly those of clinical concern, in urban rivers flowing in this urban area. The method developed herein to explore antimicrobial resistance is based on cultural and molecular approaches completed by hydrological, hydrogeological, climatic, and physico-chemical data. Hospital vicinity and urbanization density significantly increase cultivable bacterial community, fecal bacteria from human origin, and prevalence of β-lactamases and extended-spectrum β-lactamases encoding-genes without an increase in 16S rDNA gene abundance. A total of 22 multidrug Enterobacterales have been isolated. All Escherichia coli (n = 10) and Klebsiella pneumoniae (n = 6) isolated on a made-house media carried β-lactamases genes, blaCTX-M being the most prevalent (87%), followed by blaTEM (56%) and blaSHV (37%), 56% of these strains carrying two or three of these genes. In urban settings, water quality and infectious risk are generally linked to wastewater treatment plants effluents. This study shows that running waters in urbanized area contribute to the dissemination of antimicrobial resistance, making these environments a reservoir for resistant bacteria with important consideration.

International audience; This chapter presents the main food characteristics impacted by both the nature and the content of mineral ions through a few selected examples. It provides on the involvement of mineral ions on taste perception of different food systems, on the colour of foods, and on the texture and structure of foods. The chapter focuses on the taste influence of minerals in model dairy products. Meat is recognized as an important source of protein in the human diet, but it also provides a large variety of minerals, which are involved in many physiological functions and are thus essential for good health. Along with aroma, taste and texture perception, colour is one of the key factors for food appreciation by consumers. It provides symbolic and associative information about the food. The Maillard reaction plays an important role in the appearance and flavour of food subjected to cooking or roasting.

International audience; Sourness is mainly caused by the detection of protons. This perception may act as a warning signalling the presence of a high concentration of acid dangerous for the body, of unripe fruits, or of spoiled foods contaminated by microorganisms. Numerous organic and mineral acids are responsible for sourness. A low level of sour taste is attractive to humans and animals in some foods such as citruses, while it is aversive when present at a high level. The release of acids in the mouth during eating and the perception of sourness may be influenced by the food matrix composition and structure. The perception of particular aromas can modulate acid perception through perceptual interactions. Overall, there is less work on sour perception than on bitter, salty, and sweet perceptions. Saliva has been suggested to act as a buffering system affecting the way we perceive the sourness of acids. Sourness also influenced the overall acceptability of imitation fruit beverages prepared with these acids.

This study presents a new high density rain gauges network installed in urban area to study spatio-temporal structure and variability of precipitation at small scales. The preliminary results concerning gauges calibration and characterization of the rainfall spatial variability at fine scale are discussed.In urban areas, the impervious surfaces connected to the drainage system leads to highly dynamic flows. The flood and runoff risk characterization requires fine spatiotemporal scale to describe hydrological model input data :rainfall within spatial scale of less than 1km and temporal scale close to 1minis necessary for urban hydrological applications and risk assessment. In order to characterize small-scale rainfall spatiotemporal variability, a dense rain gauges network is deployed at Montpellier (France) with inter-gauges distances from 100m to 1km. Currently, 9 tipping bucket rain gauges associated with 9 anemometers are acquiring rainfall and wind norm intensity every minutes. The network density and extension will be increased soon.The first year measurements highlight a spatial variability of the 1-minute rainfall at the subkilometer scale. This observed variability is analyzed in view of the measurement uncertainty (gauge calibration, gauge error, bias due to the gauge location) to identify the natural rainfall variability.This contribution presents the new densely extensive rainfall network measurement, the typing bucket raingauge calibration and highlights that the observed 1-minute rainfall intensity variability is significant and cannot be only explained by the measurement uncertainties.

This study focus on the catchment of Ambouli wadi which is one of the country’s largest watersheds covering 794 km² (3.5 % of the total area of the Republic of Djibouti). Because of its groundwater resources, this exoreic watershed is of major importance. Indeed, the aquifer is the main source of drinking water supply for the city of Djibouti-city. In addition, this wadi is also responsible for floods causing human suffering and severe economic damages. Despite the importance of the catchment for the development of Djibouti-city, Ambouli wadi has been the subject of few scientific studies. This partly explains the scarcity of rainfall stations and therefore data in this area. Analysis of the spatio-temporal variability of rainfall is required to assess the risk of flooding. In an arid country like the Republic of Djibouti flash floods are an important concern for the management of water resources systems and risk prevention and protection. The desertic climate of the country is characterized by high levels of temperature and evaporation, and also by very weak and irregular annual rainfall, distributed in two major seasons : a cooler season (from October to March) with high relative humidity and low temperatures comprised between 22°C and 30°C, and a hot and dry season (from June to September). Rain data were collected from a network of 9 raingauge stations at different time scales, from monthly to hourly. These data are provided by the national meteorological agency (4 stations) and the early warning system of CERD National Research Center (5 stations). The spatio-temporal variability of rainfall, is characterized using the Standardized Precipitation Index (SPI) and the analysis of rainfall normals over 30 years (1951-1980 and 1961-1990). Long time series data were available from 4 of the 9 stations: (Djibouti-serpent, Djibouti-aeorodrome, Oueah and Arta). At annual scale, the variability is clearly described by a succession of dry and humid years. Also, the monthly rainfall clearly demonstrates the well-known bimodal precipitation regime of east Africa. It shows, two peaks corresponding to the « long rain » and the « short rain » rainy seasons, which correspond to the period of March-April-May and of October-November-December, respectively. On the other hand, we also observe a dry period which is characterized by a rainfall deficit (negative rainfall index for almost all the stations) corresponding to the boreal summer (June to September). Daily data is currently collecting from the Djibouti-aerodrome station (1981-2017) for a better understanding of the precipitation regime. Rainy days are computed from daily data (rainfall > 1 mm) and we find an annual average of 11 wet days with a minimum in 1988 (1 rainy day) and a maximum in 1993 (23 rainy days).

International audience; The structure of extruded pea flour can affect chewing performances. Our objective was to relate the bolus properties (fragmentation, moisture content and viscosity) of chewed extruded pea snacks to their structure. In order to have control over oral physiological parameters, we opted for an in vitro approach using a chewing simulator, the variables of which were the flow rate of artificial salivary fluid and chewing time. The structure of the extruded pea snacks was characterized by its density and protein solubility in dithioerythritol (DTE), which reflected the amount of protein aggregates cross-linked by disulphide bonds. The particle size distribution and median width (D-50) of the bolus fragments were determined by imaging technique. Bolus viscosity and saliva uptake (Delta WC) were respectively determined by capillary rheometry and gravimetric method. Extruded snacks were persistently reduced to small particles (similar to 2 mm) during chewing process following a unique curve of D-50 = f (chewing time) fitted by a power function. Delta WC evolution during chewing process was expressed as a function of the structure index, defined as the product of the snacks' relative density by protein solubility in DTE. The boluses' viscosity exhibited a shear thinning behaviour the consistency index of which was negatively correlated to the saliva uptake (Delta WC) through a plasticization coefficient (alpha). alpha values (< 2) were much smaller than those reported for cereal products (15-30) and depended on protein solubility in DTE.

Today, urban stormwater management is moving towards Stormwater Control Measures (SCMs) that encourage water storage and infiltration to reduce urban runoff and contaminant transfer. Modelling tool...

International audience; To counteract the negative effect of salt overconsumption on health, strategies have been developed to reduce the salt content in food products. Among them, two promising strategies based on odour-induced saltiness enhancement and the heterogeneous distribution of flavour compounds were combined and assessed in four-layer cream-based snacks. To investigate the relationship between saltiness enhancement, temporal release and perception of flavour compounds in hot snacks with heterogeneous distribution of salt and aroma compounds, complementary techniques were used: nose space PTR-Tof-MS (Proton Transfer Reaction-Time of Flight–Mass Spectrometry) to assess the release of aroma compounds in vivo, and ATI (Alternate Time-Intensity) and TDS Temporal Dominance of Sensations) to evaluate perception as a function of time. The obtained results confirmed that the strategy of concentrating salt in the outer layer of a multilayer product was the optimal solution with respect to taste intensity. Heterogeneous salt distribution decreased aroma compound release and consequently aroma intensity but in different ways according to both salt and added aroma distribution in the food matrix. The salty taste enhancement could be due to the initial strong dominance of the salty sensation at the very beginning of the eating process. The involved mechanisms rely on a combination of physico-chemical and perceptual effects which are not clear yet.

International audience; During rainfall events, a wide range of contaminants generated by urban areas are transferred into rivers. Modelling tools are increasingly required by decision makers to assess the effects of urban development and mitigation measures on urban runoff quality. However, representing the spatial heterogeneity of urban land cover in water quality modelling is a real challenge. This study presents a methodology to analyze and characterize the land cover of an urban catchment within a water quality model. The application site is the urban river Verdanson located in Montpellier city (France), where the climate is Mediterranean. Firstly, a time effective original method of identifying homogeneous urban surfaces in terms of build-up/wash-off processes from an existing land-use map and aerial photo interpretation is presented. Secondly, the sensitivity of model outputs to the discretization of a catchment into homogeneous land cover types, called Water quality Response Units (WQRUs), is tested. The results reveal that discretizing the catchment into WQRUs enhances the relevance of hydrological outputs and provide more flexibility for a calibration of Total Suspended Solids wash-off parameters. The findings open interesting opportunities to integrate catchment-scale land cover data into the modelling of wash-off processes and allow urban runoff managers to assess the influence of urban land use planning scenarios on water quality.

Dans beaucoup de regions, le contexte physique et la severite des etiages que les cours d'eau connaissent ont conduit les hydrometres a utiliser de nombreux seuils comme controles hydrauliques afin...

International audience; The BaGaTel database, guided by an ontology of dairy gels, has been developed to organise and integrate data on dairy products (process, composition, structure, nutritional, sensory and environmental quality), using a common vocabulary and metadata organisation. BaGaTel was queried to explore relationships between composition, rheological properties and sensory perception in 68 model cheeses from six different projects. Principal component analyses were performed on the total set of 68 samples and on sample subsets. Sensory hardness was well explained by the low moisture-in-non-fat-substances ratio. As expected, salty taste was correlated with salt content but, interestingly, in cheese with a low amount of salt, salty taste was less intense at low water content and was perceived better with increased chewing activity. In cheeses with a high amount of salt, salty test was less intense at high protein content. Salty taste was also influenced by lipid content and correlated with fat perception.

International audience; Decreasing obesity or cardiovascular disease can be achieved by eating healthier foods with reduced contents of fat, salt and sugar. However, these ingredients have a significant impact on the sensory quality of the food products that contain these ingredients, especially cooked sausage, chorizo, dry sausage, cheese and muffins. In this study, consumer appreciation of these five commercialized products (non reformulated versions) and their respective reformulated versions with reduced contents of salt, fat and sugar was tested. An original home experiment was performed to assess consumer appreciation in natural consumption conditions. The experiment was divided into two steps that correspond to a pleasantness rating and a willingness to pay task. The two measurements were expected to yield comparable results with two aspects of consumer appreciation. Non-reformulated and reformulated versions were compared with a store brand and a trademark in a ranking task to evaluate their pleasantness positioning on the market. This latter experiment, which was conducted in a laboratory, enabled the validation of the home experiment. The results indicated that the cooked sausage reformulation did not maintain consumer appreciation and reduced its positioning on the market. For cheese and muffins, the reformulation did not affect the product pleasantness. The reformulation of dry sausage and chorizo not only maintained consumer appreciation but also increased pleasantness, which was consistent with a higher reservation price of approximately 12% compared to the other samples. For most products in this experiment, new technologies contributed to significant reduction in fat, salt or sugar whilst maintaining consumer appreciation.

Densely urbanized areas generate a wide range of contaminants exerting pressures on the quality of downstream rivers. As urban areas are in permanent extension, assessing the potential evolution of water quality and the effects of mitigation measures is a real challenge. Modelling tools could be helpful in decision making but require sound field data for calibration steps. The present study focuses on the urban river Lez that crosses the area of Montpellier city. Due to the Mediterranean climate, extreme precipitations intensify the transfer of contaminants by generating land runoff and significant sewer overflow. The spatiotemporal variability in microbiological and chemical contamination of the Lez river and its tributaries is characterized through field campaigns. Three low flow campaigns and a flood event are presented here, with a focus on the most urbanized sub-catchment: Verdanson. Hydrological conditions are shown to have a strong impact on the water quality in terms of concentrations of fecal indicator bacteria, organotins, trace metals and polycyclic aromatic hydrocarbons. As a first step towards the modelling of the water quality during a flood event, a sensitivity analysis was performed to test how land cover could be properly be taken into account in the modelling process. The analysis reveals that discretizing the catchment into land cover-homogeneous subcatchments enhances the suitability of water quality model outputs, keeping good outputs of the hydrological model. Consequently, a rigorous description of land cover is required to properly assess the impacts of territorial dynamics on water quality.

Salt reduction in foods is becoming an important challenge to preserve population health from severe diseases as recommended by different health agencies worldwide. Among the reduction strategies already evaluated in order to lower sodium salt content in foods, the use of cross-modal interactions between taste and odour, regardless of saltiness, was revealed to be a very promising method to improve saltiness perception. Cross-modal odour-taste interaction, as means to enhance salty taste in foods, is reviewed. Salt-related odours can enhance salty taste in water solutions containing a low level of sodium chloride through odour-induced changes in taste perception. Odour-induced saltiness perception enhancement (OISE) depends on salt concentration (intensity). OISE was also found to be effective in low salt content solid model cheese but was texture- and composition-dependent. A significant enhancement in saltiness perception induced by Comté cheese and sardine odours was observed only in model foods with soft textures. In ternary odour-sour-salty solutions, sourness additively enhanced saltiness perception with salt-related odours. Finally, in cream-based food systems, a strategy combining OISE and heterogeneous distribution of stimuli was found to compensate for a greater than 35% decrease in salt content without significant loss of acceptability. However, variation in the composition of the food matrix influenced aroma and salt release and consequently the overall saltiness perception. A better knowledge of the mechanisms involved in cross-modal perceptual interactions at the central level should allow for the optimization of their use as salt reduction strategies for healthier food design.

International audience; To provide answers to sustainability challenges, a database called BaGaTel, guided by the PO2 ontology, has been built to integrate data to reformulate dairy products taking into account nutritional and sensory properties together with environmental concerns. In this paper, BaGaTel was queried to address questions dealing with the eco-design of hard cheese processing, in relation to composition, sensory quality and rheological properties. For the formulation of hard cheese, BaGaTel made it possible to estimate missing data in a dataset supposing that samples have common characteristics. For environmental concerns, BaGaTel gave hints about relevant data that need to be acquired and made possible the estimation of missing data. The common vocabulary and structure provided by the PO2 ontology allowed combining and integrating into BaGaTel data from different projects, giving relevant answers to different questions, and therefore proving its suitability as a support tool for multi-criteria assessment of food systems.

Temporal aroma compound release during eating is a function of the physicochemical properties of the food matrix, aroma compounds, and oral physiology of individuals. However, the influence of each parameter on the release of each aroma component should be clarified. Two flavored lipoprotein matrices varying in composition were chewed in a chewing simulator that reproduced most of the physiological functions of the mouth. Aroma compound releases (butanoic acid, 2-heptanone, ethyl butyrate, 3-octanone, and 2-nonanone) were followed in real time by direct connection of the device to APCI-MS (atmospheric pressure chemical ionization mass spectrometry). Each oral parameter was controlled and decoupled using the in vitro device. The food matrix composition had only a low impact on aroma compound release, but the controlled oral parameters had significantly different influences on the release of aroma compounds according to their physicochemical characteristics. The release of certain compounds seemed more sensitive to bite force, while others seemed more sensitive to the shearing angle. The salivary flow rate primarily influenced the more hydrophobic compounds. Significant interactions were also observed between shear angle, salivary flow rate, and lipoprotein matrix composition, mainly for the release of the more hydrophobic volatile compounds; this needs further investigations to be clarified., This research was funded by INRA (Internal); the Conseil Régional de Bourgogne (France) and European Regional Development Fund (ERDF) funded the equipment used in this project (development of chewing simulator, mass spectrometer), We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)

International audience; Orally Disintegrating Tablets (ODTs) are used to restore the nutritional status of people suffering from swallowing pathologies such as dysphagia. ODTs are consumed without water intake and are easily swallowed. The main active compounds of ODTs are vitamins and minerals. These nutrients can have a bad taste or aftertaste, which can be masked by sweetening or flavoring. To ensure the effectiveness of masking strategies and to prescribe a product to patients with acceptable sensory qualities, it is essential to perform a precise and complete sensory characterization of these ODTs. Temporal dominance of sensations (TDS) and temporal check-allthat- apply (TCATA) methods were chosen to characterize the temporal sensory perceptions during the consumption of four ODTs varying in galenic forms and flavoring because of their particularly acute temporality in flavor perception. The ODTs presented common and individual sensory properties, mainly related to their galenic form and to the nature of the active ingredients. The use of a nose-clip to stop retro-nasal airflow showed that flavoring had a minimal impact on the sensory taste qualities of the ODTs. A comparison between the TDS and TCATA results indicates that these tests are capable of providing complementary information on the dynamic sensory qualities of the products studied. Although results were generally similar for both methods, TDS showed a greater number of differences in sensory taste attribute, whereas TCATA was more discriminating. These methods allowed for a better understanding of the evolution of sensory perceptions of these ODTs during their consumption, which could help to optimize masking strategies and develop new products with acceptable sensory properties.

International audience; In humans, food oral processing (FOP) is the first step in the digestive process. It prepares the food for swallowing and to undergo the process of digestion. During chewing, the food is comminuted by the combined action of chewing and saliva to form a bolus. The particle size of the bolus is reduced due to the action of the tongue and the teeth, and the saliva is continuously produced by the salivary glands to humidify and impregnate the food. Saliva lubricates the bolus and enables the cohesion of particles to prepare for swallowing. During food oral processing, the compounds responsible for food avour and taste are released, leading to the perception of food organoleptic properties and significantly contributing to the consumer's acceptability of the product. Understanding this process of food breakdown and bolus formation thus appears to be a way to revisit food functional properties. However, this process is extremely complex, and as such, its description necessitates a combination of many quantities from different disciplines, i.e., physics, chemistry, physiology, psychology, behavioural science and food science. It depends, on one hand, on food properties and on the other hand, it depends on oral physiology. However, large inter-individual variability is commonly observed, which has important consequences on avour release and perception. The challenge for the food industry is to be able to develop food considering this large variability, and sensory and nutritional constraints. This challenge is particularly relevant when specific populations (i.e., elderly, infants or obese subjects) are considered.

Water quality indexes (WQI) are a practical way to evaluate and compare the level of chemical contamination of different water bodies and to spatially and temporally compare levels of pollution. The purpose of this study was to check if these indexes are appropriate for intermittent rivers under arid and semi-arid climates. A literature review enabled the comparison of 25 water quality indexes to discern their capability to evaluate spatial (inter and intra catchment) and temporal (high and low water flow conditions) variations in water quality in three Mediterranean intermittent rivers: the River Vene (France) and the Oued Fez and the River Sebou (Morocco). Hierarchical cluster analysis identified groups of WQI with similar behavior and brought to light the 6 most distinguishing indexes. Whatever the hydrological conditions at the two sites, both the ME-MCATUHE and NCS indexes, which were developed for Morocco and Greece, and the CCMEWQI and BCWQI indexes, which were developed for non-arid or semi-arid zones, gave appropriate water quality evaluations.