A domestic-like carrot cooking methodology for multiple research applications.

Domestic-oriented research focusing on food requires methodologies that closely mimic practices occurring in home kitchens while meeting scientific standards. Currently however, there is a lack of methodologies that can be implemented in both laboratory and home environments. This paper proposes a method that fulfills the scientific requirements of repeatability and reproducibility, while utilizing commonly available materials and processes found in the average household. The method is applied to the preparation, boiling, and seasoning of roots of Daucus carota L. ("carrots"), which can be employed in various scientific fields with only minor adjustments. Three scientific experiments utilizing this methodology are presented, namely sensory evaluation, ionic chromatography measurements, and NMR experiments. In the existing literature, numerous protocols have been used for carrot sample preparation, hindering direct comparisons between studies. In this paper we would like to highlight the ability of the methodology to enhance comparability, as well as its potential utilization in other research applications. The main principles underlying the proposed methodology can also be extrapolated to prepare samples of several other vegetables or cereals.•Comprehensive guidelines for standardizing the shapes, lengths, and widths of carrots are outlined, ensuring minimal variability while preserving the integrity of the raw material.•The cooking method for carrots is tailored to utilize commonly available household materials, while meeting scientific standards required for research purposes.•Seasoning practices involving readily available domestic materials, like commercial salt, are suggested.

Predicting odor profile of food from its chemical composition: Towards an approach based on artificial intelligence and flavorists expertise.

Odor is central to food quality. Still, a major challenge is to understand how the odorants present in a given food contribute to its specific odor profile, and how to predict this olfactory outcome from the chemical composition. In this proof-of-concept study, we seek to develop an integrative model that combines expert knowledge, fuzzy logic, and machine learning to predict the quantitative odor description of complex mixtures of odorants. The model output is the intensity of relevant odor sensory attributes calculated on the basis of the content in odor-active comounds. The core of the model is the mathematically formalized knowledge of four senior flavorists, which provided a set of optimized rules describing the sensory-relevant combinations of odor qualities the experts have in mind to elaborate the target odor sensory attributes. The model first queries analytical and sensory databases in order to standardize, homogenize, and quantitatively code the odor descriptors of the odorants. Then the standardized odor descriptors are translated into a limited number of odor qualities used by the experts thanks to an ontology. A third step consists of aggregating all the information in terms of odor qualities across all the odorants found in a given product. The final step is a set of knowledge-based fuzzy membership functions representing the flavorist expertise and ensuring the prediction of the intensity of the target odor sensory descriptors on the basis of the products' aggregated odor qualities; several methods of optimization of the fuzzy membership functions have been tested. Finally, the model was applied to predict the odor profile of 16 red wines from two grape varieties for which the content in odorants was available. The results showed that the model can predict the perceptual outcome of food odor with a certain level of accuracy, and may also provide insights into combinations of odorants not mentioned by the experts.

Perspectives on Nasal Odorant Metabolism Research.

Olfaction is a multi-step process. At a peripheral level, nasal odorant metabolism contributes to olfaction via signal termination, variation, and regulation. We summarize current techniques used to investigate nasal odorant metabolism and give an outlook on future approaches, such as nasal tissue models and their potential contributions in future research directions.

Exploring the effects of mixture composition factors and perceptual interactions on the perception of icewine odor: An olfactometer-based study.

The perception of food odor, derived from complex mixtures of odorants, remains poorly understood. This study investigated how key odorants of icewine influence odor mixture perception and mixture-induced perceptual interactions. A multichannel olfactometer was used to deliver 90 mixtures to 36 trained participants who used a Rate-All-That-Apply method to rate the odor samples. Results showed that adding odorants to a mixture affected both the characteristic odor of the individual component and other odor characteristics, revealing specific perceptual interactions. Combining up to six odorants with icewine odor influenced a maximum of two odor characteristics in the mixture, regardless of the specific combination. Interestingly, adding odorants had a stronger impact on the overall mixture odor profile than omitting them, particularly when manipulating fewer than three odorants. These findings emphasize the complexity of odor mixture perception and provide new insights into the influence of key odorants on the aroma of wine.

Covid-19 affects taste independent of taste-smell confusions: results from a combined chemosensory home test and online survey from a large global cohort.

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with 10 household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 5,225 self-reported a respiratory illness and were grouped based on their reported COVID test results: COVID-positive (COVID+, N = 3,356), COVID-negative (COVID-, N = 602), and COVID unknown for those waiting for a test result (COVID?, N = 1,267). The participants who reported no respiratory illness were grouped by symptoms: sudden smell/taste changes (STC, N = 4,445), other symptoms excluding smell or taste changes (OthS, N = 832), and no symptoms (NoS, N = 416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% confidence interval (CI): 15-28%), 47% in smell (95% CI: 37-56%), and 17% in oral irritation (95% CI: 10-25%) intensity. There were medium to strong correlations between perceived intensities and self-reported abilities (r = 0.84 for smell, r = 0.68 for taste, and r = 0.37 for oral irritation). Our study demonstrates that COVID-19-positive individuals report taste dysfunction when self-tested with stimuli that have little to none olfactory components. Assessing the smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and may help to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.

Dedicated odor-taste stimulation design for fMRI flavor studies.

BACKGROUND: Flavor is a mental representation that results from the brain's integration of at least odor and taste, and fMRI can highlight brain-related areas. However, delivering stimuli during fMRI can be challenging especially when administrating liquid stimuli in supine position. It remains unclear how and when odorants are released in the nose and how to improve odorant release. NEW METHOD: We used a proton transfer reaction mass spectrometer (PTR-MS) to monitor the in vivo release of odorants via the retronasal pathway during retronasal odor-taste stimulation in a supine position. We tested techniques to improve odorant release, including avoiding or delaying swallowing and velum open training (VOT). RESULTS: Odorant release was observed during retronasal stimulation, before swallowing, and in a supine position. VOT did not improve odorant release. Odorant release during stimulation had a latency more optimal for fitting with BOLD timing than after swallowing. COMPARISON WITH EXISTING METHOD(S): Previous in vivo measurements of odorant release under fMRI-like conditions showed that odorant release occurred only after swallowing. On the contrary, a second study found that aroma release could occur before swallowing, but participants were sitting. CONCLUSION: Our method shows optimal odorant release during the stimulation phase, meeting the criteria for high-quality brain imaging of flavor processing without swallowing-related motion artifacts. These findings provide an important advancement in understanding the mechanisms underlying flavor processing in the brain.

Eater-oriented knowledge framework for reducing salt and dietary sodium intake (scoping review).

Salt and dietary sodium are ubiquitously present in daily food practices and, at the same time, reducing salt intake presents an important public health issue. Given such an ambivalent position of salt in human diet, we argue that public health guidelines toward dietary sodium reduction require an eater-oriented knowledge framework. In this article we are making the first steps toward a flexible interdisciplinary database which would include nutritional, socio-economic, cultural, material, and socio-psychological determinants of salt consumption for comprehensive public health campaigns. We employ an explorative scoping review of academic articles and reports, limiting our review to the original data on salt or sodium consumption published in English or French between 2000 and 2022. We describe salt consumption as research object, identifying its representation in different research fields, data sources, methodologies, samples, and links with nutritional recommendations. We synthesize existing approaches via four eater-oriented categories: Socio-demographic and cultural descriptors of salt consumers; Knowledge, attitudes, and beliefs on nutritional norms; Salt practices associated with dietary or medical regimes; Salt materialities: interactions and contexts. In each category, we identify the dominant relational features, i.e., what kind of 'eater-salt' relation is being put forward. We thus build an interdisciplinary documentary base of dietary sodium consumption factors. We discuss the results, suggesting that comprehensive nutritional policies for global salt reduction require interdisciplinary eater-oriented data frameworks.

Covid-19 affects taste independently of smell: results from a combined chemosensory home test and online survey from a global cohort (N=10,953).

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with ten household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 3,356 self-reported a positive and 602 a negative COVID-19 diagnosis (COVID+ and COVID-, respectively); 1,267 were awaiting test results (COVID?). The rest reported no respiratory illness and were grouped by symptoms: sudden smell/taste changes (STC, N=4,445), other symptoms excluding smell or taste loss (OthS, N=832), and no symptoms (NoS, N=416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% Confidence Interval (CI): 15-28%), 47% in smell (95%-CI: 37-56%), and 17% in oral irritation (95%-CI: 10-25%) intensity. In all groups, perceived intensity of smell (r=0.84), taste (r=0.68), and oral irritation (r=0.37) was correlated. Our findings suggest most reports of taste dysfunction with COVID-19 were genuine and not due to misinterpreting smell loss as taste loss (i.e., a classical taste-flavor confusion). Assessing smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and helps to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.

OOPS, the Ontology for Odor Perceptual Space: From Molecular Composition to Sensory Attributes of Odor Objects.

When creating a flavor to elicit a specific odor object characterized by odor sensory attributes (OSA), expert perfumers or flavorists use mental combinations of odor qualities (OQ) such as Fruity, Green, and Smoky. However, OSA and OQ are not directly related to the molecular composition in terms of odorants that constitute the chemical stimuli supporting odor object perception because of the complex non-linear integration of odor mixtures within the olfactory system. Indeed, single odorants are described with odor descriptors (OD), which can be found in various databases. Although classifications and aroma wheels studied the relationships between OD and OQ, the results were highly dependent on the studied products. Nevertheless, ontologies have proven to be very useful in sharing concepts across applications in a generic way and to allow experts' knowledge integration, implying non-linear cognitive processes. In this paper, we constructed the Ontology for Odor Perceptual Space (OOPS) to merge OD into a set of OQ best characterizing the odor, further translated into a set of OSA thanks to expert knowledge integration. Results showed that OOPS can help bridge molecular composition to odor perception and description, as demonstrated in the case of wines.

Nasal Odorant Competitive Metabolism Is Involved in the Human Olfactory Process.

Within the peripheral olfactory process, odorant metabolizing enzymes are involved in the active biotransformation of odorants, thus influencing the intensity and quality of the signal, but little evidence exists in humans. Here, we characterized the fast nasal metabolism of the food aroma pentane-2,3-dione in vivo and identified two resulting metabolites in the nasal-exhaled air, supporting the metabolizing role of the dicarbonyl/l-xylulose reductase. We showed in vitro, using the recombinant enzyme, that pentane-2,3-dione metabolism was inhibited by a second odorant (e.g., butanoic acid) according to an odorant-odorant competitive metabolic mechanism. Hypothesizing that such mechanism exists in vivo, pentane-2,3-dione, presented with a competitive odorant, both at subthreshold concentrations, was actually significantly perceived, suggesting an increase in its nasal availability. Our results, suggesting that odorant metabolizing enzymes can balance the relative detection of odorants in a mixture, in turn influencing the intensity of the signal, should be considered to better manage flavor perception in food.

Reducing Sodium Content in Cheeses While Increasing Salty Taste and Fat Perception Using Aroma.

Excess salt (NaCl) and fat intake are major causes of chronic diseases, but reducing such components without affecting acceptability is a major challenge. Here, we set out to examine whether added aroma in lower salt cheese can enhance saltiness and fat perception. Low-salt cheese samples were grated through a homogenizer, and then aroma solution, sardine aroma (salt-associated), butter aroma (fat-associated) and a mix of sardine and butter aromas were added. The results confirmed that grating changes cheese texture, leading to induced taste perception. In addition, a significant saltiness enhancement was induced by sardine aroma and to a lesser extent by butter aroma, while significant fat perception enhancement was only induced by blended aroma. These findings show that aroma addition can be a strategy to compensate for sodium reduction in commercial cheese. Concerning fat perception, the addition of aroma can be a good strategy to compensate for low-fat in commercial cheeses. However, the mechanisms involved seem complex and need to be elucidated.

Assessing the contribution of odor-active compounds in icewine considering odor mixture-induced interactions through gas chromatography-olfactometry and Olfactoscan.

The sensory impact of odor-active compounds on icewine aroma could be influenced by perceptual interactions with other odor-active compounds. The aim of this study was to establish an approach to evaluate the contribution of odor-active compounds found in icewine considering mixture-induced perceptual interactions. By comparing the impact of key odorants detected in icewine following a gas chromatography-olfactometry approach with an Olfactoscan-based methodology using a background odor of icewine, 69 odor zones were detected, and their related compounds were further identified. The results revealed that icewine background odor could exert odor masking or enhancement on key odorants when they are considered in the complex wine aroma buffer. Several compounds can induce qualitative changes in the overall wine aroma. This study underlined the efficiency of Olfactoscan-like approaches to screen for the real impact of key odorants and to pinpoint specific compounds that could be highly influential once embedded in the aroma buffer.

Biological constraints on configural odour mixture perception.

Animals, including humans, detect odours and use this information to behave efficiently in the environment. Frequently, odours consist of complex mixtures of odorants rather than single odorants, and mixtures are often perceived as configural wholes, i.e. as odour objects (e.g. food, partners). The biological rules governing this 'configural perception' (as opposed to the elemental perception of mixtures through their components) remain weakly understood. Here, we first review examples of configural mixture processing in diverse species involving species-specific biological signals. Then, we present the original hypothesis that at least certain mixtures can be processed configurally across species. Indeed, experiments conducted in human adults, newborn rabbits and, more recently, in rodents and honeybees show that these species process some mixtures in a remarkably similar fashion. Strikingly, a mixture AB (A, ethyl isobutyrate; B, ethyl maltol) induces configural processing in humans, who perceive a mixture odour quality (pineapple) distinct from the component qualities (A, strawberry; B, caramel). The same mixture is weakly configurally processed in rabbit neonates, which perceive a particular odour for the mixture in addition to the component odours. Mice and honeybees also perceive the AB mixture configurally, as they respond differently to the mixture compared with its components. Based on these results and others, including neurophysiological approaches, we propose that certain mixtures are convergently perceived across various species of vertebrates/invertebrates, possibly as a result of a similar anatomical organization of their olfactory systems and the common necessity to simplify the environment's chemical complexity in order to display adaptive behaviours.

Metallic taste prevalence in patients treated for cancer: a systematic literature review and meta-analysis.

BACKGROUND: Metallic taste (MT) is a taste abnormality often reported by cancer patients. The aim of this systematic review was to exhaustively report MT incidences in cancer patients and to evaluate the risk of bias in the pertinent studies in accordance with a meta-analysis approach. METHODS: The research objective was to determine the prevalence of MT in patients treated for cancer. A literature search was conducted using PubMed, Web of Science, and Embase. The authors each screened articles and evaluated the eligibility and individual risk of bias for each article. Then, all of the results were compared. A meta-analysis was conducted on studies that specifically focused on MT evaluation. RESULTS: Very few articles have been published on the incidence of MT among taste and smell abnormalities in cancerology (22 of 1674, 1.3%), and the quality of the reports on MT was often low. The most common bias was the methodology used for MT evaluation. Pooling the results of the 22 studies led to an estimated MT incidence in the cancer patient population of 29% (95% CI [0.21; 0.39]) with high and significant heterogeneity observed among the studies. A heterogeneity analysis was performed to identify the causal factors of this heterogeneity. The specific impact of MT on nutritional status (two) and quality of life (five) studies were reported, respectively, and without a specific evaluation of MT. There was no mention of oral health in any of the studies. CONCLUSION: Although in clinical practice cancer patients often report MT, its incidence has only been reported in 22 studies, most of which have a moderate to severe risk of bias. Considering the rather high prevalence of MT, more research should be conducted in this field to better identify its causes and mechanisms.

Lipidomic profile of human nasal mucosa and associations with circulating fatty acids and olfactory deficiency.

The nasal mucosa (NM) contains olfactory mucosa which contributes to the detection of odorant molecules and the transmission of olfactory information to the brain. To date, the lipid composition of the human NM has not been adequately characterized. Using gas chromatography, liquid chromatography coupled to mass spectrometry and thin layer chromatography, we analyzed the fatty acids and the phospholipid and ceramide molecular species in adult human nasal and blood biopsies. Saturated and polyunsaturated fatty acids (PUFAs) accounted for 45% and 29% of the nasal total fatty acids, respectively. Fatty acids of the n-6 family were predominant in the PUFA subgroup. Linoleic acid and arachidonic acid (AA) were incorporated in the main nasal phospholipid classes. Correlation analysis revealed that the nasal AA level might be positively associated with olfactory deficiency. In addition, a strong positive association between the AA levels in the NM and in plasma cholesteryl esters suggested that this blood fraction might be used as an indicator of the nasal AA level. The most abundant species of ceramides and their glycosylated derivatives detected in NM contained palmitic acid and long-chain fatty acids. Overall, this study provides new insight into lipid species that potentially contribute to the maintenance of NM homeostasis and demonstrates that circulating biomarkers might be used to predict nasal fatty acid content.

Compilation of data on model cheeses composition, rheological and sensory properties, from six research projects exported from the BaGaTel database.

This paper presents data on model cheeses extracted from the BaGaTel database. The data are issued from 6 different research projects in which data on composition, rheological and sensory properties were collected. The manufacturing of the 68 different samples is described. For each model cheese, data are available on final composition (lipid, protein, water, sodium), rheological properties (uniaxial compression), sensory profile analysis (texture, taste, aroma) and for some cheeses chewing activity and in vivo sodium release were also measured. The material and methods used are detailed. Scatter plots of representation of the values for each variable and each project are plotted. Pearson correlations between variables are given for specific subsets of data. The dataset is hosted in an open access data repository. This dataset will allow a comparison of sensory properties of cheeses varying in lipid, protein water and salt content and can be used for the reformulation of cheeses made with a low salt and fat content to follow food-related health recommendations, whilst fulfilling good sensory qualities.

A dataset on odor intensity and odor pleasantness of 222 binary mixtures of 72 key food odorants rated by a sensory panel of 30 trained assessors.

This paper describes data collected on a set of 222 binary mixtures, based on a set of 72 odorants chiefly found in food, rated by 30 selected and trained assessors for odor intensity and pleasantness. The data included odor intensity (IAB) and pleasantness (PAB) of the mixtures, the intensity (IA, IB) and the pleasantness (PA, PB) of the two components. Moreover, the intensity (IAmix, IBmix) of the two components' odor perceived within the mixture are included. The quality of the dataset was evaluated by checking subjects' performance and by testing repeatability using the 24 duplicated trials for each attribute. This set of experimental data would be especially valuable to investigate theories of odor mixture perception in human and to test new models to predict odor perception of odor mixtures.

Perceptual interactions among food odors: Major influences on odor intensity evidenced with a set of 222 binary mixtures of key odorants.

This study explored the impact of perceptual interactions on the odor intensity of 222 binary mixtures designed from 72 odorants found in food products. Odor intensity was rated by 30 trained subjects. The results showed that in most cases, the components' odor was perceived within the mixture and their intensity remained the same as in the unmixed situation in 54.3% of cases. Masking was the second major effect (44.8%) and occurred more frequently when components' pleasantness was significantly different. Synergy occurred in a small number of cases (0.9%) and only for four compounds. The overall odor intensity of the mixture was determined to be equal to the strongest component in most cases (73.9%), while partial addition was observed as the second most frequent effect (21.7%), especially when the components had equal intensity. Overall, this work provides general rules about the outcome to expect when mixing key components of food aromas.

Salt and Aroma Compound Distributions Influence Flavour Release and Temporal Perception While Eating Hot-Served Flans.

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.