Oro-sensory Exposure Research Articles

The heat is on: Consumers modify their oral processing behavior when eating spicy foods

Food texture properties and consumer characteristics influence oral processing behaviors. Little is known about oral processing behavior of pungent spicy foods. In two experiments, we investigated how adding ground dried chilies to tomato soup or beef patties and curried rice altered oral processing behaviors. In Experiment One, tomato soups differing in concentration of added ground dried chilies (0.01, 0.03, 0.20 or 0.40% w/w) were consumed (n = 23). In Experiment Two, lunch meals that differed in added ground dried chilies consisting of beef patties (0.0, 0.6 or 1.2% w/w) and curried rice (0.0, 0.4 or 1.0% w/w) were consumed (n = 49). Sip/bite sizes were determined using hidden balances. Oral processing behavior was quantified using video recordings followed by post hoc annotations of specific behaviors. When eating tomato soup, increasing oral burn was associated with increasing number of water sips, water intake and total time between sips. For the solid meals (beef patties and curried rice), increasing oral burn was associated with increased time between bites and total sips of water; conversely, total oral exposure time, total number of chews and number of chews per bite all decreased with greater burn. Saliva content and rate of saliva incorporation into the solid food bolus increased with added ground dried chilies while oral exposure time decreased. We conclude consumers adapt their oral processing behaviors to oral burn of solid foods by reducing oro-sensory exposure time, chewing bites less, increasing time between bites, and consuming more water, potentially to mitigate the discomfort associated with the burn imparted by ground dried chilies.

Do Behaviors Such As Eating Faster or Taking Larger Bites Moderate the Portion Size Effect?

ObjectivesIndividuals eat more when served larger portions, and this may be influenced by eating-related microstructural behaviors. In a controlled study, we explored whether microstructural components of eating such as eating rate, bite size, bite count, and meal duration influenced the portion size effect. MethodsIn a randomized crossover design, 44 adults aged 18 to 68 y (66% women; 45% with overweight or obesity) ate lunch in the laboratory once a week for four weeks. The meal consisted of a single dish of pasta (1.4 kcal/g) that was varied in portion size (400,500, 600, or 700 g) along with ∼700 g of water. Intake was assessed by weighing items before and after the meal. To characterize eating microstructure, meals were video-recorded to assess bite counts and meal duration, which were used to calculate mean eating rate (g/min) and mean bite size (g/bite). The influence of eating microstructure on the portion size effect was analyzed by random coefficients models. ResultsAs larger portions were served, meal intake increased in a curvilinear manner (P < 0.0001). Compared to the smallest portion, intake of the largest portion increased by a mean (±SEM) of 123 ± 16 g (43%). As portions were increased, there were similar increases in bite count (35%) and meal duration (38%; both P < 0.0001), but only small increases in mean bite size (8%; P = 0.019) and no significant change in eating rate (P = 0.92). Measures of eating microstructure did not moderate the portion size effect but did have main effects on intake across all portions. Individuals ate more at the meal when they ate faster, took larger bites, took more bites, or ate for longer (all P < 0.0001). Body mass index did not influence eating microstructure or the strength of the portion size effect but had a modest negative effect on intake across all meals (–5.9 ± 2.7 g/unit increase in BMI; P = 0.046). ConclusionsEating-related microstructural behaviors influenced meal intake across portions, but did not moderate the effect of portion size on intake. Individuals who ate faster and took larger bites ate more across all portions, possibly as a result of reduced oro-sensory exposure, which can delay meal termination. Targeted interventions to alter components of eating microstructure have the potential as strategies to reduce overconsumption. Funding SourcesNIDDK, Jenny Craig.

Effects of Oro-Sensory Exposure on Satiation and Underlying Neurophysiological Mechanisms-What Do We Know So Far?

The mouth is the first part of the gastrointestinal tract. During mastication sensory signals from the mouth, so-called oro-sensory exposure, elicit physiological signals that affect satiation and food intake. It has been established that a longer duration of oro-sensory exposure leads to earlier satiation. In addition, foods with more intense sweet or salty taste induce earlier satiation compared to foods that are equally palatable, but with lower taste intensity. Oro-sensory exposure to food affects satiation by direct signaling via the brainstem to higher cortical regions involved in taste and reward, including the nucleus accumbens and the insula. There is little evidence that oro-sensory exposure affects satiation indirectly through either hormone responses or gastric signals. Critical brain areas for satiation, such as the brainstem, should be studied more intensively to better understand the neurophysiological mechanisms underlying the process of satiation. Furthermore, it is essential to increase the understanding of how of highly automated eating behaviors, such as oral processing and eating rate, are formed during early childhood. A better understanding of the aforementioned mechanisms provides fundamental insight in relation to strategies to prevent overconsumption and the development of obesity in future generations.

Increased oral processing and a slower eating rate increase glycaemic, insulin and satiety responses to a mixed meal tolerance test.

Variations in specific oral processing behaviours may contribute to differences in glucose, insulin and satiety responses to a standardised test meal. This study tested how natural variations in oral processing between slower and faster eaters contribute to differences in post-prandial glucose (PP glucose), insulin response (PP insulin) and post-meal satiety for a standardised test meal. Thirty-three participants with higher risk for type 2 diabetes consumed a standardised test-meal while being video recorded to derive specific oral processing behaviours. Plasma glucose, insulin and satiety measures were collected at baseline, during and post meal. Participants were split into slower and faster eaters using median split based on their eating rates and individual bolus properties were analysed at the point of swallow. There were large variations in eating rate (p < 0.001). While there was no significant difference in PP glucose response (p >0.05), slower eaters showed significantly higher PP insulin between 45 and 60 min (p < 0.001). Slower eaters had longer oro-sensory exposure and increased bolus saliva uptake which was associated with higher PP glucose iAUC. Faster eating rate and larger bolus particle size at swallow correlated with lower PP glucose iAUC. A slower eating rate with greater chews per bite significantly increased insulin iAUC. Faster eaters also consistently rated their hunger and desire to eat higher than slower eaters (p < 0.05). Natural variations in eating rate and the associated oral processing contributed to differences in PP glucose, PP insulin and satiety responses. Encouraging increased chewing and longer oral-exposure time during consumption, may promote early glucose absorption and greater insulin and satiety responses, and help support euglycaemia. ClinicalTrials.gov identifier: NCT04522063.

Impact of food texture modifications on oral processing behaviour, bolus properties and postprandial glucose responses

Several studies have demonstrated food texture manipulation on oral processing behaviour (OPB). We explored the effect of texture-differences of equivalent carbohydrate load on OPB, bolus properties and postprandial glycaemic responses (PPG). In a randomised cross-over, within-subjects, non-blinded design, healthy male participants (N = 39) consumed fixed portions of white rice (WR) and rice cake (RC) while being video recorded to measure microstructural eating behaviours. PPG was compared between test foods over a period of 120-min, and the bolus properties and saliva uptake at swallow were measured for both test foods. RC displayed higher instrumental hardness, chewiness and Young's modulus than WR (p = 0.01), and participants perceived RC as more springy and sticky than WR (p < 0.001). The RC meal was chewed more per bite (p < 0.001) and consumed at a faster eating rate (p = 0.033) than WR. WR bolus particles were smaller at swallow (p < 0.001) with a larger total surface area (p < 0.001), compared to RC. The glucose response for RC was significantly higher during the first 30-min postprandial period (p = 0.010), and lower in the later (30–120 min) postprandial period (p = 0.031) compared to WR. Total blood glucose iAUC did not differ significantly between WR and RC meals despite their large differences in texture, OPB and bolus properties. Oro-sensory exposure time was a significant predictor of glucose iAUC30min for both test meals (RC, p = 0.003; WR, p = 0.029). Saliva uptake in the bolus was significantly positively associated with blood glucose during the first 30-min postprandial period for the RC meal (p = 0.008), but not for WR. We conclude that food texture modifications can influence OPB and bolus properties which are key contributors to the dynamic evolution of the glycaemic response. Total blood glucose responses were the same for both test foods, though differences in oral processing and bolus properties influenced temporal changes in PPG.

How oro-sensory exposure and eating rate affect satiation and associated endocrine responses—a randomized trial

BackgroundLonger oral processing decreases food intake. This can be attributed to greater oro-sensory exposure (OSE) and a lower eating rate (ER). How these factors contribute to food intake, and the underlying physiological mechanisms, remain unclear.ObjectivesWe aimed to determine the independent and simultaneous effects of OSE and ER on satiation and associated endocrine responses.MethodsForty participants in study 1 [mean ± SD age: 24 ± 4 y; BMI (in kg/m2): 22 ± 2] and 20 in study 2 (mean ± SD age: 23 ± 3 y; BMI: 23 ± 2) participated in a 2 × 2 randomized trial. In both studies, participants ate chocolate custard with added caramel sauce (low OSE) or caramel fudge (high OSE) and with short (fast ER) or long breaks (slow ER) in between bites, until fullness. In study 2, endocrine responses were measured during the meal.ResultsIn study 1, participants ate (mean ± SEM) 42 ± 15 g less in the slow- than in the fast-ER condition, only within the high-OSE condition (P = 0.04). In study 2, participants ate 66 ± 21 g less in the high- than in the low-OSE condition and there were no intake differences between slow and fast ER (P = 0.35). Eight minutes after starting to eat, insulin concentrations increased by 42%–65% in all treatments compared with the control. At the end of the meal, insulin concentrations were 81% higher in the high-OSE, slow-ER than in the low-OSE, fast-ER condition (P = 0.049). Pancreatic polypeptide (PP) increased by 62%, 5 min after meal onset in the low-OSE, fast-ER condition (P = 0.005). Ghrelin concentrations did not change.ConclusionsGreater OSE increases insulin responsiveness. In contrast, PP responses are stronger when OSE is reduced and ER is fast. Insulin and PP responses may mediate the independent effects of OSE and ER on food intake. These may be beneficial eating strategies, particularly for type 2 diabetic patients, to control food intake and maintain glucose homeostasis.This trial was registered at trialregister.nl as NL6544.

Can eating harder textured foods slowly influence appetite?

AbstractIntroductionChewing a greater number of chews per bite has been shown to increase fullness, lower hunger levels and lead to a lower energy intake, when compared to chewing each bite fewer times. Increased levels of fullness and decreased levels of hunger have also been observed after consuming harder textured foods which require more chewing activity and have a longer oro-sensory exposure time. The aim of this study was to investigate whether consumption of foods differing in texture, classified as ‘fast’ or ‘slow’ foods, combined with differences in oral processing behaviours (chewing normally or more slowly), has an impact on self-reported hunger, fullness and satiety outcomes.Materials and MethodsThis is an interim analysis of a randomised crossover experiment designed to test the impact of both oral processing behaviours and food texture on self-reported hunger, fullness and satiety. Participants consumed two breakfasts of different texture (a ‘fast’ yoghurt and fruit compote option, and a ‘slow’ granola option) twice; once at their normal rate of eating and once after being instructed to eat slowly. Measures of self-reported appetite (hunger, fullness, satiety, desire to eat and prospective food consumption) were assessed using a visual analogue scale at three time points; baseline (minimum 20 minutes before consumption), immediately pre-consumption and post-consumption. Statistical analysis was conducted in SPSS; paired sample t tests and one-way analysis of variance was conducted to measure whether change in appetite ratings between the time points differed between the four breakfast options.ResultsData were collected from 16 healthy volunteers (study aiming to recruit n = 21; mean age 32.1 y, female n = 13, 81.3%). For all four breakfast options, levels of hunger, desire to eat and prospective food consumption significantly decreased, and levels of fullness and satiety significantly increased between both baseline and post-consumption, (p &lt; 0.05) and between pre-consumption and post-consumption (p &lt; 0.05). However, amongst the four breakfast options, no significant differences were observed in change in these appetite measures between baseline and post-consumption and pre- and post-consumption (p &gt; 0.05).DiscussionThis interim analysis demonstrates no differences in mean change in appetite measures for breakfast options of different texture chewed normally or more slowly. Analysis of the full study will determine the effect of oral processing behaviours and food texture on self-reported hunger, fullness and satiety outcomes.

Unaware of the amount consumed: Systematic error in estimating food- and drink intake

BackgroundOur current food environment promotes overconsumption due to the overrepresentation of foods that have a high calorie density and can be easily consumed. These food characteristics lead to limited oro-sensory exposure, which may lead to overconsumption due to insufficient perception of the amount consumed. Better perception of the amount eaten and thus a better ability to estimate intake may help control actual food intake through prolonged inter-meal interval and smaller meal sizes. ObjectiveThe aim of this study was to determine whether food form, flavor and portion size influence the error in estimated intake (EiE). MethodParticipants (n = 72) were recruited at a science festival where the study was also performed. The experiment had a 2 × 2 × 3 design with a reference condition. Experimental conditions differed in food form (liquid vs. solid stimuli), taste category (savory vs. sweet) and portion size (small, medium, large). Water was used as a reference condition. ResultsParticipants overestimated the amount consumed of all stimuli. The overestimation was ten times greater for solid compared to liquid products (104 ± 12 vs 12 ± 9% overestimation) and was more pronounced for sweet (75 ± 9%) than for savory products (41 ± 12%). There was a trend for larger EiE% of smaller portions. No differences were found among the differently flavored liquids including the water reference. ConclusionPeople overestimate the amount they consume of solid and sweet products more than that of liquid and savory products. This overestimation may be due to overvaluation of the oro-sensory stimulation when visual cues and intake effort are controlled for or because of learned associations. However, the uncontrolled setting of the experiment should be taken into account when drawing conclusions. Future research may replicate the study in a more controlled setting and should determine whether the overestimation of sweet solid product intake also leads to lower intake at a subsequent meal.

Extrusion cooking of cassava-soy flour with 200 g/kg wheat bran promotes slower oral processing during consumption of the instant porridge and higher derived satiety

In this study, the descriptive sensory attributes, oral processing characteristics of and subjective satiety responses for extrusion cooked cassava-soy porridge with wheat bran at 0, 100 and 200 g/kg addition levels were determined. Fifteen subjects (23–47 years, mean BMI 22.6 kg/m2) consumed 250 g of each porridge type over 8 breakfast meals while being video recorded. Oral exposure time and number of bites, and eating and bite rates were determined. Subjects rated hunger, fullness and desire to eat before meal, post meal and periodically over 3 h post consumption. A separate panel profiled the descriptive sensory attributes of the porridges. The addition of wheat bran increased visually perceived viscosity and presence of visible particles. The porridge with 200 g/kg wheat bran was eaten with more bites and at a slower rate thus, having longer oro-sensory exposure. Also, the porridge with 200 g/kg wheat bran led to greater reduction in subjective reported hunger compared to the other porridges. Wheat bran as a source of dietary fibre has the potential to be incorporated as a component of extruded starch-rich foods to produce instant products which can promote satiety.

Exacting Responses: Lack of Endocrine Cephalic Phase Responses Upon Oro-Sensory Exposure.

Oro-sensory exposure (OSE) to food plays an important role in the regulation of food intake. One proposed underlying mechanism is the occurrence of cephalic phase responses (CPRs). CPRs include the pre-digestive endocrine responses induced by food-related sensory input. Yet, whether OSE duration or sweetness intensity affects CPRs is unknown. The objective of this study was to determine the independent and interactive effects of oro-sensory duration (chewing) and stimulation intensity (sweetness) on endocrine CPRs and satiation. Eighteen males (22 ± 2 years, BMI 22 ± 2 kg/m2) participated in a 2 × 2 randomized study with a control condition. Each session participants performed modified sham feeding (MSF) with one of the four gel-based model foods. During the control session no MSF was performed. Model foods differed in chewing duration (hard or soft texture) and sweetness (low or high intensity). During each session, eight blood samples were collected up till 25 min after MSF onset. Subsequently, food intake from an ad libitum lunch was measured. No typical CPR was found for insulin, pancreatic polypeptide (PP), and ghrelin. However, the overall PP response was 1.1 times greater for the hard sweet MSF condition compared to control (p = 0.02). Overall ghrelin responses were 1.1 times greater for the hard model food compared to the soft model food conditions (p = 0.003). These differences in endocrine response were not associated with differences in food intake at the subsequent meal. Exploratory sub-analysis of the responsive insulin curves showed that after 2.5 min of MSF the hard texture model foods insulin concentrations were 1.2 greater compared to the soft texture. These findings indicate that texture hardness and sweetness increase the overall PP response and that MSF on hard texture increases the overall ghrelin response compared to soft texture model foods. However, MSF on model foods does not lead to a typical CPR. This study, among others, shows that there are major dissimilarities in the endocrine responses to food stimulation between individuals. This emphasizes the importance of considering cephalic responders and non-responders. More research is needed to understand CPRs in relation to food texture and taste properties.

Effect of oro-sensory exposure on cephalic phase responses and satiation

Effect of oro-sensory exposure on cephalic phase responses and satiation

Comparison of oro-sensory exposure duration and intensity manipulations on satiation

Oro-sensory exposure (OSE) is an important factor in the regulation of food intake with increasing OSE leading to lower food intake. Oral processing time and taste intensity both play an important role in OSE but their individual contribution to satiation is unknown. We aimed to determine the independent and combined effects of oral processing time and taste intensity on satiation.Fifty eight participants (23±9y, BMI 22±2kg/m2) participated in a 2×2 factorial randomized crossover study in which they consumed one of four gel-based model foods until satiation during four sessions. Model foods were offered ad libitum and differed in texture (soft or hard texture, yielding shorter and longer oral processing time) and sweetness (low or high intensity). Model foods were isocaloric and were matched for flavor and palatability. Outcome measures were intake of the model food and the microstructure of eating behavior, such as number of chews and eating rate.There was an overall significant effect of texture (p<0.001) but not sweetness (p=0.33) on intake with a 29.2% higher intake of the soft model foods compared to the hard model foods. After correction for palatability the difference in intake between the soft and hard model foods was 21.5% (p<0.001).The number of chews was significantly lower for the soft (10.1±6.2) than for the hard (26.9±6.2) model foods (p<0.001), which resulted in a significantly lower eating rate (soft, 26.3±10.2 and hard, 15.3±7.1g/min, p<0.001).These results show that increasing texture hardness of gel model foods decreases food intake independent of sweet taste intensity. The higher number of chews and faster eating rate may cause this effect. In conclusion, oro-sensory exposure duration rather than taste intensity appears to be the main determinant of food intake.

Comparison of partial and global projective mapping with consumers: A case study with satiating cheese pies

In the present work the performance of global projective mapping and partial projective mapping based on texture and flavor for sensory characterization of a novel food category (satiating food product) was compared. Eight different fresh-cheese pie formulations were designed to obtain different sensory (principally texture) characteristics which could affect expected satiating perception. Three groups of consumers evaluated the samples using one of the following methodologies: global projective mapping (G-PM) (n=47), partial projective mapping based on flavor (F-PM) (n=53), and partial projective mapping based on texture (T-PM) (n=61). In addition, the expected satiating capacity of each cheese pie sample was scored on a nine-point scale. Results showed that the vocabulary used by consumers for describing the sensory characteristics of samples did not largely differ between global and partial projective mapping tasks. However, T-PM and F-PM tasks provided more detailed information than G-PM in each specific modality. Results suggested that when consumers performed the global projective mapping task they mainly took into account flavor characteristics for evaluating global similarities and differences among samples. In addition, hedonic attributes were more frequently mentioned in G-PM. Fresh cheese, sugar, corn starch and egg were the basic ingredients that conferred the fresh-cheese pies their typical, characteristic flavor and texture. The addition of whey or soy proteins, wheat bran or glucomannan increased expected satiating capacity which could be related to changes in texture (harder, more compact) leading to longer orosensory exposure. The addition of glucomannan caused the largest changes in the sensory characteristics of the cheese pies which in turn would be related to a decrease in perceived flavor intensity. Studying the interplay between formulations, sensory characteristics, expected satiating capacity and consumer liking could largely contribute to the development of this novel food category.

Relating HPMC concentration to elicited expected satiation in milk-based desserts

Previous research has shown that multiple factors influence perceptions of the satiating capacity of a food. Sensory properties, especially texture, play a role in eliciting expected satiation/satiety. The present work analysed some rheological and texture-related cues to the expected satiation that nine milk-based desserts prepared with three different levels of hydroxypropylmethylcellulose, HPMC (1.5, 2.0 and 2.5 g) elicited in consumers (n = 113). Two variations were introduced in order to obtain different textures: adding diary cream and extra skimmed milk powder. The temporality (appearance and duration) of sensory perceptions was assessed by the temporal dominance of sensations method and was related to the expected satiating capacity elicited by the desserts. Relative expected satiation (RES) was measured on four nine-point picture scales showing nine increasingly larger standardized portions of the comparison food. The participants were also asked to score their liking for the samples on hedonic scales.In the low HPMC concentration samples, the first sensations to appear were thin and creamy, while fondant and a little mouth-coating sensation emerged close to swallowing. In the high HPMC concentration samples, with longer consumption times, thick, gummy and creamy appeared in the first stages, and adhesive and mouth-coating when close to swallowing.The RES results depended greatly on the HPMC concentration, but also on the addition of cream or extra milk powder which elicited significantly higher RES values than for the samples without additions. The HPMC concentration in the system and the temporality of the sensations it elicited (orosensory exposure) seemed to modulate the desserts' satiating ability.

Hydrocolloids for enhancing satiety: Relating oral digestion to rheology, structure and sensory perception

Satiety expectations can be closely related to the structural changes that take place in the mouth. An important role of hydrocolloids is to impart viscosity, which has a key effect on the feelings of richness, mouthcoating and fullness. In this study, native and modified corn starch, λ-carrageenan and guar gum were used to formulate milkshakes. Expected satiety was rated (106 consumers) and the perception of various attributes was studied. The rheological properties of the milkshakes without and with added saliva were analysed and observed with a light microscope during in vitro oral digestion.Disintegration of the swollen starch granules by saliva was observed mainly in the modified starch sample. The structure of the milkshakes prepared with λ-carrageenan and guar gum was preserved better. It could be hypothesized that the starch would provide lower expected satiety due to the extensive in-mouth disintegration. However, the sensory analysis showed that the modified starch milkshakes obtained the highest expected satiety scores, with consumers finding them homogeneous, thick in the mouth and very creamy. These results suggested that consumers related satiety more with the thick and creamy characteristics at the very start of the consumption than with the loss of structure in mouth. Sensory properties affect the assessment of the satiating capacity, especially texture, which is directly related to the orosensory exposure and, therefore, to the feeling of fullness that the milkshakes elicit. The present study casts light on the factors affecting in-mouth perception of different hydrocolloids used to design foods with enhanced satiety.

Influence of meal texture on eating rate and food intake. Results from three ad-libitum trials

Foods that can be eaten quickly with large bite sizes and little chewing are believed to produce a poorer satiety response due to reduced oro-sensory exposure and faster eating rates (Forde et al. 2013a). Few studies have examined whether it is possible to reduce eating rate and food intake by increasing the texture of realistic meal components. Three sequential studies investigated whether eating rate (g/min) and energy intake for a lunchtime meal could be reduced by manipulating the texture of the meal components. The studies compared eating rate and ad-libitum food intake for whole and pureed versions of three realistic lunchtime meals using (i) a between groups comparison (N = 160), (ii) a cross-over comparison (N = 23) and (iii) cross-over comparison with a measure of compensatory eating (N = 50). Findings showed that eating rate and intake were influenced by the texture of some meal components, and that it was possible to reduce overall food consumed by combining meal textures that required smaller bite sizes, more chews per bite and longer oro-sensory exposure within the meal. The compensatory eating measure showed that reductions in energy intake were not compensated for at the next meal, highlighting that these texture interventions could be used to reduce overall daily energy intake. These findings may be applied to the design of foods that could be used to slow eating rate, decrease food intake and produce sustainable reductions in overall energy intake.

Both a higher number of sips and a longer oral transit time reduce ad libitum intake

BackgroundA higher eating rate leads to a higher food intake, possibly through shorter orosensory exposure to food. The transit time in the oral cavity and the number of bites or sips per gram (inversely related to bite or sip size) are main contributors that affect eating rate. The separate role of these two aspects on satiation and on orosensory exposure needs further clarification. ObjectiveThe objective of the first study was to investigate contributions of the number of sips per gram (sips/g) and oral transit time per gram (s/g) on ad libitum intake. The objective of the second study was to investigate both aspects on the total magnitude of orosensory exposure per gram food. MethodsIn study 1, 56 healthy male subjects consumed soup where the number of sips and oral transit time differed by a factor three respectively: 6.7 vs. 20sips/100g, and 20 vs. 60s/100g (2×2 cross-over design). Eating rate of 60g/min was kept constant. In study 2, the effects of number of sips and oral transit time (equal as in study 1) on the total magnitude of orosensory exposure per gram soup were measured by time intensity functions by 22 different healthy subjects. ResultsHigher number of sips and longer oral transit time reduced ad libitum intake by respectively ∼22% (F(1, 157)=55.9, P<0.001) and ∼8% (F(1, 157)=7.4, P=0.007). Higher number of sips led to faster increase in fullness per gram food (F(1, 157)=24.1, P<0.001) (study 1). Higher number of sips and longer oral transit time both increased the orosensory exposure per gram food (F(1, 63)=23.8, P<0.001) and (F(1, 63)=19.0, P<0.001), respectively (study 2). ConclusionHigher number of sips and longer oral transit time reduced food intake, possibly through the increased the orosensory exposure per gram food. Designing foods that will be consumed with small sips or bites and long oral transit time may be effective in reducing energy intake.

Oral processing characteristics of solid meal components, and relations with food composition, sensory attributes & expected-satiation

The current obesogenic food environment is characterized by energy dense, softly textured foods that can be eaten quickly. Previous studies suggest that oral processing characteristics such as large bite size, low number of chews and low orosensory exposure contribute to the low satiating efficiency of these foods. The current study investigated the oral processing characteristics of 35-solid meal components and examined associations between oral processing characteristics, food composition, sensory properties and expected satiation. A panel of 15 subjects consumed 50 g of 35-foods representing various staples (potatoes, rice, pasta), vegetables (broccoli, carrot), and protein rich foods such as meat and fish. Subjects were video-recorded during consumption of each food and their eating behaviours were coded for the number of bites, chews and swallows and derived measures such as chewing-rate, eating-rate, bite-size, and orosensory residence time. Subjects rated expected fullness for the 35-foods and the sensory differences were quantified using a separate trained sensory panel. Oro-sensory residence time was highly correlated with the number of chews (R2 = 0.98) and chew-rate was relatively constant at approximately 1 chew/s. Expected fullness was positively correlated with energy density (R2 = 0.40), protein (R2 = 0.33) and the sensory attributes chewiness (R2 = 0.15) and saltiness (R2 = 0.12). Foods that were consumed in smaller bites, were chewed for longer and were expected to impart a higher satiation. This information may be used to design foods/meals lower in energy and higher in satiating efficiency per kcal consumed.

Texture and satiation: The role of oro-sensory exposure time

One of the characteristics of the current obesogenic food supply is the large availability of foods that can be ingested quickly. Controlled nutrition intervention studies have shown that the ingestion of simple energy containing beverages, which are consumed very quickly, do not lead to a lower compensatory intake of other foods. One of the theories behind this observation is that calories that are ingested quickly are not well sensed by the sense of taste, and do not lead to an adequate satiety response. This idea is confirmed by the results of a series of studies, where we have shown that the low satiation/satiety response of beverages can be largely attributed to their short oral residence time. Prolonging the oro-sensory exposure time to foods leads to earlier meal termination and/or a higher satiety response. The low satiation/satiety response to simple energy containing beverages is congruent with the observation from studies on the cephalic phase response to foods, i.e. the physiological response to sensory signals. Energy containing beverages do not lead to an adequate cephalic phase response. Various recent studies showed that slower eating leads to higher levels of satiety hormones. These results are in line with the idea that the sense of taste is a nutrient sensor which informs the brain and the gut about the inflow of nutrients. The sense of taste has an important contribution to the satiating effect of foods. One of the challenges in future research is to see whether or not these proofs of principles can be applied in longer term studies with regular commercial foods. This may make our obesogenic food supply more satiating, and may lead to a lower energy intake.

Both Longer Oral Sensory Exposure to and Higher Intensity of Saltiness Decrease Ad Libitum Food Intake in Healthy Normal-Weight Men

Orosensory exposure to sweetness has been shown to be important in satiation, whereas the effect of exposure to a salty taste on satiation is not known. The primary objective was to investigate the effect of orosensory exposure time to and intensity of saltiness in soup on ad libitum intake. The secondary objective was to investigate the effect of intensity on bite size. Fifty-five healthy men consumed ad libitum from both a low-salt (LS) and a high-salt (HS) creamy tomato soup in 2 exposure time conditions (“long” and “short”) and a free condition (“free”). Bites were administered and controlled via a pump. In the long condition, bites of 5 g were administered in 2 s at intervals of 5 s (exposure time: 24 s/min). In the short condition, bites of 15 g were administered in 3 s at intervals of 15 s (exposure time: 12 s/min). The eating rate was equal in the long and short conditions (60 g/min). In the free condition, participants adjusted their bite sizes at intervals of 15 s. The short condition resulted in ~34% higher ad libitum intake compared to the long condition (P < 0.001); there was no interaction with intensity. Ad libitum intake of HS soup was ~9% lower than LS soup (P < 0.001). The free condition showed that HS soup was consumed with smaller bite sizes during the first half of the intake period (P < 0.05). Longer orosensory exposure and higher saltiness intensity both decreased food intake, although orosensory exposure had more impact than intensity. Prolonging the orosensory exposure per food unit may be helpful to reduce food intake.