Age related impairments in ingestion from a large population based-sample.

OBJECTIVES: Epidemiological data regarding the evolution of problems related to mastication and swallowing with age are lacking. This study aims to (i) describe changes in oral function with age, using data from a large French population, (ii) validate online, self-report uses of an ICF questionnaire in older persons, and (iii) assess whether impairment is related to avoidance of certain foods, xerostomia, body mass index (BMI) and oral health related quality of life (OHRQoL). METHODS: Volunteers aged ≥18 years with internet access completed a series of questionnaires on sociodemographic, anthropometric and oral health characteristics (oral function, Xerostomia Index (XI), OHRQoL, reasons for avoidance of certain food). Oral function was assessed using items derived from the International Classification of Functioning (ICF). Five ICF items related to ingestion function and six items related to activities and participation were used. A validation study was undertaken to identify those with poor chewing ability and low salivary flow amongst older participants reporting impairment. FINDINGS: 39 597 individuals were included. The prevalence of individuals with impairment for ICF items related to ingestion function and oral activity (eating, drinking and speaking), and the percentage of participants with poor OHRQoL increased significantly with age (p < 0.001). Each ICF item was significantly associated with OHRQoL (p < 0.001), XI (p < 0.001), BMI (p < 0.001) and avoidance of certain food due to chewing or swallowing difficulties. CONCLUSION: Overall, 21.5% and 13.5% of the study population had chewing and/or biting impairments respectively, which might affect food selection and consumption. These findings raise individual and population-based issues. Further studies are needed to assess whether impairment in oral function might increase frailty in older individuals, and also to compare data with those from other countries.

Astringency sensitivity to tannic acid: Effect of ageing and salivary proline-rich protein levels.

The link between salivary composition and sensitivity to astringency as a function of age has still not been established. In this work, we propose the hypothesis that ageing leads to changes in the concentration of salivary proline-rich proteins (PRPs), which alters the astringency perception threshold with age. To test this hypothesis, astringency sensitivity to tannic acid and saliva was assessed in 30 elderly people and 24 young people. Basic PRPs (bPRPs) and glycosylated PRPs (gPRPs) were quantified immunochemically via western blot analysis. The results showed that the amounts of bPRPs and gPRPs were similar between the young and elderly groups. However, a positive correlation between the gPRP amount and astringency threshold was observed only in the young group, while a negative correlation between the bPRP amount and astringency threshold was observed only in the elderly group. This finding suggests differences in the contribution of PRP type to astringency perception as a function of age.

A scoping review of emotion regulation and inhibition in emotional eating and binge-eating disorder: what about a continuum?

BACKGROUND: Emotional eating is defined as a nonpathological eating behavior, whereas binge-eating disorder (BED) is defined as a pathological eating behavior. While different, both share some striking similarities, such as deficits in emotion regulation and inhibition. Previous research has suggested the existence of an "eating continuum" that might reflect the increased severity of overeating behaviors, that is, from nonpathological overeating to BED. The main aims of this scoping review were to explore in the literature the idea of a continuum between emotional eating and BED and to observe whether deficits in emotion regulation and inhibition follow this continuum in terms of severity. The other aims were to hopefully clarify the ill-defined concept of overeating, to question the potential role of positive emotions and to identify potential knowledge gaps. METHOD: A systematic scoping review was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. Two databases (PubMed/Medline and PsycINFO) were examined in complete accordance with the beforehand sharply defined eligibility and exclusion criteria. The main criteria included adults (≥ 18) with emotional eating, BED or overeating and emotion regulation and inhibition as exposure criteria. RESULTS: Thirty-two studies were included in this scoping review. If the results showed a link between emotional eating and BED, with the presence of inhibition and emotion regulation deficits in both eating behaviors, no mention of a continuum between emotional eating and BED was found. CONCLUSION: In the absence of research directly comparing emotional eating and BED in the same studies and testing the potential increase in severity of emotion regulation and inhibition deficits along this continuum, there is currently no certainty that a continuum exists between emotional eating and BED. In the end, the idea of a continuum in terms of increased severity of overeating and in terms of emotion regulation and inhibition deficits between emotional eating and BED appears to be a gap in knowledge in the literature. This scoping review highlights the need for further research to identify knowledge gaps.

Emotional eating (EE) is defined as a nonpathological eating behavior, whereas binge-eating disorder (BED) is defined as a pathological eating behavior. While different, both share some striking similarities, such as deficits in emotion regulation (ER) and inhibition. Previous research has suggested the existence of an "eating continuum" that might reflect the increased severity of overeating behaviors, that is, from nonpathological overeating to BED. The main aims of this scoping review were to explore in the literature the idea of a continuum between EE and BED and to observe whether deficits in ER and inhibition follow this continuum in terms of severity. A systematic scoping review was conducted, and thirty-two studies were included in this review. If the results showed a link between EE and BED, with the presence of inhibition and ER deficits in both eating behaviors, no mention of a continuum between EE and BED, or in relation to a continuum, was found. Thus, in the absence of research directly comparing EE and BED in the same studies and testing the potential increase in severity of ER and inhibition deficits along this continuum, there is currently no certainty about the existence or absence of such a continuum.

Guiding the formulation of soft cereal foods for the elderly population through food oral processing: Challenges and opportunities.

As the elderly population is growing steadily, more age-friendly food products that allow them to cover their nutritional needs and are enjoyable need to be designed. Since their oral physiology is considerably altered, the study of Food Oral Processing has become an essential discipline in food development, as it takes into consideration the complex interactions between food structure, oral processing, physiology and perception. Cereals are staple foods in many countries, and their consumption as bakery products is popular among the elderly population. In addition, when fortified with pulse proteins, they can help meet the protein needs of seniors and help fight against sarcopenia. For these reasons, this chapter presents an overview of the various aspects involved in the oral processing and formulation of soft cereal foods, translating them into challenges and opportunities that are of relevance to the design of realistic soft cereal foods targeted for the elderly that are nutritious and sensory appealing. This review focuses on the healthy elderly population and does not intend to cover the needs of the dependent elderly suffering from chronical diseases.

Astringency Sensitivity to Tannic Acid: Effect of Ageing and Saliva.

Astringency is an important sensory characteristic of food and beverages containing polyphenols. However, astringency perception in elderly people has not been previously documented. The aim of the present work was to evaluate sensitivity to astringency as a function of age, salivary flow and protein amount. Fifty-four panellists, including 30 elderly people (age = 75 ± 4.2 years) and 24 young people (age = 29.4 ± 3.8 years), participated in this study. Astringency sensitivity was evaluated by the 2-alternative forced choice (2-AFC) procedure using tannic acid solutions. Whole saliva was collected for 5 min before and after the sensory tests. The results showed that the astringency threshold was significantly higher in the elderly group than the young group. No correlation was observed between the salivary protein amount and threshold value. However, a negative correlation between salivary flow and threshold was observed in the young group only. These results showed a difference in oral astringency perception as a function of age. This difference can be linked to salivary properties that differ as a function of age.

Role of human salivary enzymes in bitter taste perception.

The molecules that elicit taste sensation are perceived by interacting with the taste receptors located in the taste buds. Enzymes involved in the detoxification processes are found in saliva as well as in type II cells, where taste receptors, including bitter taste receptors, are located. These enzymes are known to interact with a large panel of molecules. To explore a possible link between these enzymes and bitter taste perception, we demonstrate that salivary glutathione transferases (GSTA1 and GSTP1) can metabolize bitter molecules. To support these abilities, we solve three X-ray structures of these enzymes in complexes with isothiocyanates. Salivary GSTA1 and GSTP1 are expressed in a large panel of subjects. Additionally, GSTA1 levels in the saliva of people suffering from taste disorders are significantly lower than those in the saliva of the control group.

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.

Molecular mechanisms of aroma persistence: From noncovalent interactions between aroma compounds and the oral mucosa to metabolization of aroma compounds by saliva and oral cells.

The present study aims to reveal the molecular mechanisms underlying aroma persistence, as it plays a major role in food appreciation and quality. A multidisciplinary approach including ex vivo experiments using a novel model of oral mucosa and saliva as well as in vivo dynamic instrumental and sensory experiments was applied. Ex vivo results showed a reduction in aroma release between 7 and 86% in the presence of the thin layer of salivary proteins covering the oral mucosa (mucosal pellicle). This reduction was explained by hydrophobic interactions involving the mucosal pellicle and by the ability of oral cells and saliva to metabolize specific aroma compounds. The in vivo evaluation of exhaled air and perception confirmed the ex vivo findings. In conclusion, this work reveals the need to consider physiological reactions occurring during food oral processing to better understand aroma persistence and open new avenues of research.

Effects of oenological tannins on aroma release and perception of oxidized and non-oxidized red wine: A dynamic real-time in-vivo study coupling sensory evaluation and analytical chemistry.

Addition of oenological tannins claims to have a positive impact on wine stability, protection from oxidation and likely sensory persistence. However, their role on red wine aroma during oxidation is controversial. The present study aims at investigating the effect of addition of oenological tannins on wine flavour (mainly aroma) before and after air exposure. Temporal Dominance of Sensations, a dynamic sensory evaluation, was coupled with a dynamic chemical measurement (nosespace analysis) using a Proton-Transfer-Reaction Mass-Spectrometer connected to the nasal cavity of 17 assessors. Results showed that the oxidation of a non-oaked Pinot Noir red wine decreases the fruity aroma dominance and increases the maderised and prune one. A contextual decrease of the fruity ethyl decanoate and increase of oxidative Strecker aldehydes are observed. Ellagitannins but not proanthocyanidins preserved perception of fruitiness and prevented increase of maderised notes. Moreover, ellagitannins increase the aroma persistence mainly in the non-oxidized wine.

Oral enzymatic detoxification system: Insights obtained from proteome analysis to understand its potential impact on aroma metabolization.

The oral cavity is an entry path into the body, enabling the intake of nutrients but also leading to the ingestion of harmful substances. Thus, saliva and oral tissues contain enzyme systems that enable the early neutralization of xenobiotics as soon as they enter the body. Based on recently published oral proteomic data from several research groups, this review identifies and compiles the primary detoxification enzymes (also known as xenobiotic-metabolizing enzymes) present in saliva and the oral epithelium. The functions and the metabolic activity of these enzymes are presented. Then, the activity of these enzymes in saliva, which is an extracellular fluid, is discussed with regard to the salivary parameters. The next part of the review presents research evidencing oral metabolization of aroma compounds and the putative involved enzymes. The last part discusses the potential role of these enzymatic reactions on the perception of aroma compounds in light of recent pieces of evidence of in vivo oral metabolization of aroma compounds affecting their release in mouth and their perception. Thus, this review highlights different enzymes appearing as relevant to explain aroma metabolism in the oral cavity. It also points out that further works are needed to unravel the effect of the oral enzymatic detoxification system on the perception of food flavor in the context of the consumption of complex food matrices, while considering the impact of food oral processing. Thus, it constitutes a basis to explore these biochemical mechanisms and their impact on flavor perception.

Impact of Oral Microbiota on Flavor Perception: From Food Processing to In-Mouth Metabolization.

Flavor perception during food intake is one of the main drivers of food acceptability and consumption. Recent studies have pointed to the oral microbiota as an important factor modulating flavor perception. This review introduces general characteristics of the oral microbiota, factors potentially influencing its composition, as well as known relationships between oral microbiota and chemosensory perception. We also review diverse evidenced mechanisms enabling the modulation of chemosensory perception by the microbiota. They include modulation of the chemosensory receptors activation by microbial metabolites but also modification of receptors expression. Specific enzymatic reactions catalyzed by oral microorganisms generate fragrant molecules from aroma precursors in the mouth. Interestingly, these reactions also occur during the processing of fermented beverages, such as wine and beer. In this context, two groups of aroma precursors are presented and discussed, namely, glycoside conjugates and cysteine conjugates, which can generate aroma compounds both in fermented beverages and in the mouth. The two entailed families of enzymes, i.e., glycosidases and carbon-sulfur lyases, appear to be promising targets to understand the complexity of flavor perception in the mouth as well as potential biotechnological tools for flavor enhancement or production of specific flavor compounds.

Influence of Prebiotic Fructans on Retronasal Aroma from Elderly Individuals.

This study investigates for the first time the role of fructans with prebiotic effects (oligofructose and inulin) on retronasal aroma among elderly individuals. The impact of oligofructose (20% w/w) on retronasal aroma release was investigated using proton transfer reaction-mass spectrometry (PTR-MS) after 73 elderly individuals consumed aqueous solutions aromatized with five aroma compounds (pentan-2-one, nonan-2-one, hexan-2,3-dione, octanal and linalool). The influence of oligofructose and inulin (10% w/w) on the perceived intensity (n = 26) of two aroma descriptors (butter and floral) was also studied together with the possibility of a dumping effect on aroma evaluation due to the sweetness provided by the fructans. The results showed that the presence of oligofructose produced a significant reduction in retronasal aroma release, which could be generally explained by the physicochemical properties of aroma compounds. The presence of prebiotic fructans did not significantly affect the perceived intensity of butter and floral notes, although a dumping effect for the butter descriptor in the presence of oligofructose was observed. To conclude, these findings suggest that although fructans can exert an impact on retronasal aroma, they can be used at precise concentrations to increase the prebiotic fibre content of food products without affecting the aroma profile of foods.

Perspectives on Astringency Sensation: An Alternative Hypothesis on the Molecular Origin of Astringency.

Flavor is one of the main drivers of food consumption and acceptability. It is associated with pleasure feels during eating. Flavor is a multimodal perception corresponding to the functional integration of information from the chemical senses: olfaction, gustation, and nasal and oral somatosensory inputs. As a result, astringency, as a sensation mediated by the trigeminal nerves, influences food flavor. Despite the importance of astringency in food consumer acceptance, the exact chemosensory mechanism of its detection and the nature of the receptors activated remain unknown. Herein, after reviewing the current hypotheses on the molecular origin of astringency, we proposed a ground-breaking hypothesis on the molecular mechanisms underpinning this sensation as a perspective for future research.

Physiological and oral parameters contribute prediction of retronasal aroma release in an elderly cohort.

Malnutrition is a serious problem in the elderly while understanding flavour perception could be a tool for controlling appetite or food choices. To increase our knowledge, we characterised the health and oral physiology (oral volume, swallowing tongue force, number of teeth and salivary flow rate, protein content and antioxidant capacity) of a cohort of 54 community-dwelling French elderly as well as their individual retronasal release of five aroma compounds (2-pentanone, 2-nonanone, 2,3-hexanedione, octanal and linalool) by proton-transfer-reaction mass spectrometry (PTR-MS). In general, large variability across participants was observed in both oral physiological (>40%) and retronasal aroma release (>56%) parameters. Multivariate analyses revealed a relationship between physiological parameters (mostly salivary antioxidant capacity) and retronasal aroma release that explained up to 46% of the variability observed. This study provides new insights to understand retronasal aroma release in the elderly that could contribute to the development of personalised nutrition strategies.

The association between changes of gustatory function and changes of salivary parameters: A pilot study.

OBJECTIVE: The aim of the pilot study was to explore which of the salivary parameters best reflects improvement or deterioration of taste function. METHODS: A total of 14 patients were included. Taste ability was measured using taste strips and patients rated their symptom strength using visual analogue scales. Salivary parameters (flow rate, total proteins, proteolysis, catalase, total anti-oxidative capacity [TAC], carbonic anhydrase VI [caVI], and pH) were determined and the Beck Depression Inventory (BDI) was administered. All these parameters were measured twice with a one-year interval to acquire the changes of data. RESULTS: Patients with decreased taste function exhibited a decrease in salivary proteolysis and caVI, and an increase in salivary total protein. Patients with increased taste function also showed an increase in salivary total protein. Δ Salivary flow rate was negatively correlated with Δ taste strip scores. Δ Salivary pH was significantly lower in patients with increased taste function compared to patients with decreased taste function. Δ BDI was positively correlated with both Δ symptoms ratings. Across all patients, symptom ratings decreased while salivary total protein increased; salivary flow rate, proteolysis and caVI decreased significantly compared with baseline. CONCLUSIONS: The present longitudinal results suggest that changes of both taste function and taste complaints were accompanied by changes in salivary parameters, indicating that salivary parameters have the potential to be useful in the diagnosis of patients with qualitative taste disorders.

Role of the bolus degree of structure on the protein digestibility during in vitro digestion of a pea protein-fortified sponge cake chewed by elderly.

This study investigated the digestibility of proteins in a pea protein-fortified sponge cake, as well as the impact of the degree of structure of the bolus produced by elderly subjects on the digestibility of proteins by combining ex vivo and in vitro approaches via the standardized protocol INFOGEST. The sponge cakes were consumed by a group of 20 elderly subjects with contrasting physiology, their boli were recovered just before swallowing, and their apparent viscosity was measured to delineate the bolus degree of structure. According to this criterion, two pools were formed with boli from subjects selected at the extremes: low viscosity and high viscosity, with apparent viscosity values (at 120 s-1 ) of 124 ± 18 and 208 ± 19 Pa s, respectively. The sponge cakes and the two pools underwent in vitro digestion. Protein hydrolysis kinetics was followed by measuring the released primary amino groups (NH2 ) and by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis at different time points. For all samples, the representative bands of pea proteins disappear gradually during digestion, accompanied by the appearance of bands indicating the presence of proteins with MW < 15 kDa. In addition, the NH2 concentrations increase over time and do not differ between sponge cake and pea protein isolate. Moreover, the degree of structure of the food bolus has no significant effect on the concentration of NH2 released. These results showed that pea proteins in a fortified sponge cake are bioaccessible under standardized conditions and that the degree of structure of the bolus did not influence protein digestibility for these foods.

The Relationship Between Salivary Redox, Diet, and Food Flavor Perception.

The mouth is the gateway for entrance of food and microorganisms into the organism. The oral cavity is bathed by saliva, which is thus the first fluid that food and microorganisms will face after their entrance. As a result, saliva plays different functions, including lubrication, predigestion, protection, detoxification, and even transport of taste compounds to chemoreceptors located in the taste buds. To ensure its function of protection, saliva contains reactive harmful compounds such as reactive oxygen species that are controlled and neutralized by the antioxidant activity of saliva. Several antioxidant molecules control the production of molecules such as reactive oxygen compounds, neutralize them and/or repair the damage they have caused. Therefore, a balance between reactive oxidant species and antioxidant compounds exists. At the same time, food can also contain antioxidant compounds, which can participate in the equilibrium of this balance. Numerous studies have investigated the effects of different food components on the antioxidant capacity of saliva that correspond to the ability of saliva to neutralize reactive oxygen species. Contradictory results have sometimes been obtained. Moreover, some antioxidant compounds are also cofactors of enzymatic reactions that affect flavor compounds. Recent studies have considered the salivary antioxidant capacity to explain the release of flavor compounds ex vivo or in vivo. This article aims to review the effect of food on the antioxidant capacity of saliva and the impact of salivary antioxidant capacity on flavor perception after a brief presentation of the different molecules involved.

Oral lipolysis and its association with diet and the perception and digestion of lipids: A systematic literature review.

OBJECTIVES: This systematic literature review aims to summarize the existing scientific evidence on the association of oral lipolysis with diet and with the perception and digestion of lipids in humans and rodents. METHODS: A validated search strategy of two databases (PubMed and ISI Web of Knowledge) was carried out and the contents were screened by two independent reviewers. The quality of the included studies was critically evaluated on the basis of the Quality Assessment Criteria for Evaluating Primary Research Papers. RESULTS: From the originally identified studies (n = 2295), 17 articles met the eligibility criteria for inclusion in the analysis. Among them, only 6 articles received the maximum assessment score. The main reason for this finding was the absence of a control for the confounding bias between lipases and esterases. In rodents, oral lipolysis was principally due to the activity of lingual lipase, which was associated with the 3 selected parameters. In humans, the association parameters were principally established through indirect evidence without a clear demonstration of cause. Moreover, no specific lipase, such as lingual lipase in the case of rodents, was identified at the oral level. CONCLUSIONS: Future research efforts should focus on (i) establishing a standard procedure for oral lipolytic activity evaluation and, in particular, a methodological control to address the lipase vs esterase confounding bias and (ii) identifying the main lipases that contribute to the lipolytic activity in humans at the oral level and their respective contribution to the association parameters defined in this review.

Association of the Dietary Index Underpinning the Nutri-Score Label with Oral Health: Preliminary Evidence from a Large, Population-Based Sample.

The 2017 implementation in France of the front-of-package nutrition label known as 'Nutri-Score' was intended as a public health strategy to help individuals make healthier food choices at the point of purchase and thus help reduce chronic disease on the population level. Nutri-Score and the associated individual-level dietary index are based on the British Food Standards Agency Nutrient Profiling System (FSAm-NPS-DI). Prior research has shed light on the relation between the dietary index and various physical health outcomes, yet no studies have explored the link with oral health. We analyzed the cross-sectional association of the dietary index with oral health in a population-based sample of 33,231 adults from the French NutriNet-Santé cohort. Oral health (main dependent variable) was assessed in 2016 with the General Oral Health Assessment Index; FSAm-NPS-DI (main independent variable) was calculated using ≥3 non-consecutive 24-h dietary records, following established methodology; lower scores corresponded to better diet quality. Age-specific associations were explored via multivariable linear regression. Fully-adjusted models showed modest yet significant associations between the dietary index and oral health in younger (18-59 years) and older (60+ years) participants, with the strength of the model being more pronounced in the former compared with the latter age group (F value: 28.5 versus 6.3, both p < 0.0001). Higher diet quality was associated with a somewhat lower risk of oral health problems. Albeit preliminary, the findings support the relevance of dietary indices underpinning nutrition labels such as the Nutri-Score. Future research is needed to confirm the associations.

Assessment Wine Aroma Persistence by Using an in Vivo PTR-ToF-MS Approach and Its Relationship with Salivary Parameters.

To better understand wine aroma persistence, the nasal cavity of nine volunteers was monitored by Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) after they rinsed their mouths with three rosé wines (one control and the same wine supplemented with two tannin extracts) during four minutes. Wines were aromatised with a mixture of five target aroma compounds. Results showed that wine aroma persistence was highly compound-dependent: while esters disappeared very fast, other compounds such as linalool remained in the oral cavity for longer times after wine expectoration. A low effect of tannins (at 50 mg/L) on nasal cavity parameters was observed, with the exception for the compound ethyl decanoate that was significantly higher released in the presence of tannins. Strong interindividual differences on aroma persistence were also found. Significant positive correlations with the salivary total protein content and negative with the salivary flow were observed for specific compounds. This work has studied for the first time in vivo wine aroma persistence in real time from an analytical perspective.