Percepcija teksture namirnica u ovisnosti o sadržaju ulja, te debljini lipidnog sloja na površini usne šupljine

Lipid content in food strongly influences food perception on the level of textural properties. Lipids in contact with the tongue and palate are substantially responsible for the sensory impact of a product. The aim of this study is to investigate the impact of oil content on the thickness of lipid deposition on oral surface as well as on the mouthfeel perception. The fluorescent probe method was used to study the thickness of lipid deposition on oral surface. We observed an increase in the thickness of lipid deposition depending on the increase of oil content in oil/water dispersions. Clear correlation was shown between the thickness of lipid deposition on oral surfaces and the perception of mouthfeel. A direct measure of undisrupted deposition of food components on oral surface contributes to the understanding of the behaviour of food components in the mouth and their influence on mouthfeel perception.Sadržaj lipida u hrani snažno utječe na percepciju teksture namirnica. Lipidi u kontaktu s jezikom i nepcem u najvećoj su mjeri odgovorni za senzorska svojstva hrane. Svrha je ovoga rada bila istražiti utjecaj udjela ulja u hrani na debljinu lipidnog sloja na površini usne šupljine, kao i na percepciju teksture namirnica. Za mjerenje debljine lipidnog sloja na površini usne šupljine upotrijebljena je fluorescentna proba. Uočili smo da je debljina lipidnog sloja na površini usne šupljine proporcionalna udjelu ulja u disperzijama ulja i vode. Dokazana je izrazita korelacija između debljine lipidnog sloja na površini usne šupljine i njegove percepcije u ustima. Direktno mjerenje debljine lipidnog sloja na površini usne šupljine pridonosi razumijevanju promjene sastojaka hrane u ustima i njihovog utjecaja na percepciju teksture namirnice

Effects of eating rate on satiety:A role for episodic memory?

AbstractEating slowly is associated with a lower body mass index. However, the underlying mechanism is poorly understood. Here, our objective was to determine whether eating a meal at a slow rate improves episodic memory for the meal and promotes satiety. Participants (N=40) consumed a 400ml portion of tomato soup at either a fast (1.97ml/s) or a slow (0.50ml/s) rate. Appetite ratings were elicited at baseline and at the end of the meal (satiation). Satiety was assessed using; i) an ad libitum biscuit ‘taste test’ (3h after the meal) and ii) appetite ratings (collected 2h after the meal and after the ad libitum snack). Finally, to evaluate episodic memory for the meal, participants self-served the volume of soup that they believed they had consumed earlier (portion size memory) and completed a rating of memory ‘vividness’. Participants who consumed the soup slowly reported a greater increase in fullness, both at the end of the meal and during the inter-meal interval. However, we found little effect of eating rate on subsequent ad libitum snack intake. Importantly, after 3h, participants who ate the soup slowly remembered eating a larger portion. These findings show that eating slowly promotes self-reported satiation and satiety. For the first time, they also suggest that eating rate influences portion size memory. However, eating slowly did not affect ratings of memory vividness and we found little evidence for a relationship between episodic memory and satiety. Therefore, we are unable to conclude that episodic memory mediates effects of eating rate on satiety

Sensitivity of Genome-Wide-Association Signals to Phenotyping Strategy: The PROP-TAS2R38 Taste Association as a Benchmark

Natural genetic variation can have a pronounced influence on human taste perception, which in turn may influence food preference and dietary choice. Genome-wide association studies represent a powerful tool to understand this influence. To help optimize the design of future genome-wide-association studies on human taste perception we have used the well-known TAS2R38-PROP association as a tool to determine the relative power and efficiency of different phenotyping and data-analysis strategies. The results show that the choice of both data collection and data processing schemes can have a very substantial impact on the power to detect genotypic variation that affects chemosensory perception. Based on these results we provide practical guidelines for the design of future GWAS studies on chemosensory phenotypes. Moreover, in addition to the TAS2R38 gene past studies have implicated a number of other genetic loci to affect taste sensitivity to PROP and the related bitter compound PTC. None of these other locations showed genome-wide significant associations in our study. To facilitate further, target-gene driven, studies on PROP taste perception we provide the genome-wide list of p-values for all SNPs genotyped in the current study

Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans

Abstract Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two 'congruent' conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional 'incongruent' conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation

Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans

Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two ‘congruent’ conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional ‘incongruent’ conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulatio

Des représentations de l'espace olfactif : des récepteurs à la perception

Representations of olfactory space : from receptors to perception. Non expert subjects have acquired the ability to describe precisely their visual or auditory perceptions but their description of smells are usually short. In some case they name the odour source (lemon) but they often limit their comments to the pleasant/unpleasant feelings evoked by their olfactory sensations. This makes difficult to obtain a good representation of the human perceptual olfactory space. In order to overpass this difficulty, we asked subjects to put odorant samples in groups according to their "family resemblance". One of the major results of the study was that every subject proposed his own arrangement. From 40 subjects faced to this grouping task of 20 odorants, it was possible to extract the most common clusters used by subjects. The same series of odorant chemicals can be regarded with other points of view or at other levels of coding in the olfactory system. Chemists can use a number of different physico-chemical parameters to describe the odorant molecules and determine those playing a role in the olfactory space. Physiologists obtained consistent data on structure and function of the nervous system which support the olfactory information processing from studies in the vertebrates. For instance, we have shown images of the activities evoked by odours in the olfactory mucosa of frogs. Thus, we can compare these different representations of odours despite the inherent limitations of such a generalization.Alors que les sujets humains sans expertise professionnelle qui voient ou qui entendent ont appris à décrire avec détails plusieurs caractéristiques de leurs perceptions, les descriptions que font le plus généralement les mêmes sujets de leurs sensations olfactives sont extrêmement frustes. Dans quelques cas, ils sont capables d'énoncer le nom de la source (odeur de citron) mais le plus communément ils se contentent de décréter que cela sent bon ou mauvais ! Il est alors difficile de se représenter des propriétés de l'espace humain de perception olfactive. Pour contourner cette difficulté, on peut demander aux sujets de constituer des classes ou groupes d'échantillons odorants fondés sur leurs "airs de famille". Le premier constat est que chaque sujet propose une classification qui lui est propre. Toutefois, de l'ensemble des réponses de 40 sujets qui ont classé 20 odorants, nous avons extrait les regroupements les plus courants. Les mêmes molécules peuvent être étudiées avec d'autres points de vue ou à d'autres niveaux du système d'encodage de l'odeur. Le chimiste peut y chercher des caractéristiques physico-chimiques, et tenter de préciser celles qui influent sur la représentation de l'odorant dans un système chimio-sensoriel. Le physiologiste, en étudiant le système olfactif des vertébrés, a réuni un corpus de données cohérentes sur l'organisation et le fonctionnement du système nerveux qui traitent les informations apportées par les signaux chimiques. Nous avons, en particulier, pu recueillir une image de la représentation nerveuse de l'odeur à la périphérie du système olfactif. Nous disposons donc de plusieurs représentations de l'odeur dont nous tentons le rapprochement ici, tout en constatant les limites de ce procédé.Sicard Gilles, Chastrette Maurice, Godinot Nicolas. Des représentations de l'espace olfactif : des récepteurs à la perception. In: Intellectica. Revue de l'Association pour la Recherche Cognitive, n°24, 1997/1. Olfaction : du linguistique au neurone. pp. 85-107

Thickness of Lipid Deposition on Oral Surfaces Depending on Oil Content and Its Influence on Mouthfeel Perception

Lipid content in food strongly influences food perception on the level of textural properties. Lipids in contact with the tongue and palate are substantially responsible for the sensory impact of a product. The aim of this study is to investigate the impact of oil content on the thickness of lipid deposition on oral surface as well as on the mouthfeel perception. The fluorescent probe method was used to study the thickness of lipid deposition on oral surface. We observed an increase in the thickness of lipid deposition depending on the increase of oil content in oil/water dispersions. Clear correlation was shown between the thickness of lipid deposition on oral surfaces and the perception of mouthfeel. A direct measure of undisrupted deposition of food components on oral surface contributes to the understanding of the behaviour of food components in the mouth and their influence on mouthfeel perception

Influence of emulsion composition on lubrication capacity and texture perception

P>The role of fat content and type of surfactant for oral friction processes and texture perception of oil-in-water emulsions was assessed. Emulsions at 22% and 33% fat content containing either sodium caseinate or a sucrose ester as emulsifier were compared with viscosity-adapted aqueous solutions of dextran using both sensory evaluation and friction coefficient measurements on a tongue-palate contact model. The impact of saliva on the emulsion droplet size distribution was studied using tribology, differential interference contrast microscopy and light diffraction measurements. Emulsions at 33% and the corresponding iso-viscous aqueous solutions were discriminated in the sensory experiment whereas emulsions at 22% were not. Friction was significantly different for emulsions at 33% and the corresponding iso-viscous aqueous solutions. The difference was not significant for emulsions with 22% fat level when compared with the iso-viscous aqueous solutions. Saliva significantly decreased the friction coefficient of emulsions depending on the surfactant and amount of fat used

Fairness-Based Tasks for Assessing Children’s Perceptions of Food Quantities and Associations with Portion Selection

It is critical to develop ecologically valid experimental methods to assess consumers’ food-related behaviors. Ad libitum approaches are often used but may not be appropriate for studies with children or with products that are not typically consumed until the individual feels full. The current study presents novel methods to assess children’s size perception and portion preference for gummy candies. In the first study, 62 children (30 boys, 32 girls) aged 6 to 9 years completed two matching tasks: one using pictures on a computer screen, and a similar task where the products were physically manipulated. Results of the two matching tasks were correlated, demonstrating that a computer-based approach could be used to predict the factors influencing children’s perception of food amount: the number, size, and shape of pieces. In the second study, a portioning measure was developed to investigate whether the factors identified in the matching tasks were confirmed in a task that more closely represented portion selection in the real world. The effects observed in the matching tasks could not be replicated in the portioning task. The size of each item had no significant impact on the portion selection, suggesting that it may be possible to reduce the size of pieces in snacks where multiple pieces are typically consumed without negatively impacting perceived quantity in children, thus offering a promising strategy to nudge children toward choosing smaller portions