Behavioral measures of risk tasking, sensation seeking and sensitivity to reward may reflect different motivations for spicy food liking and consumption

Arousal and the modulation of sensory experience: evidence from food-related emotions

Across sensory systems, several stimulus collative characteristics, including intensity, novelty, complexity and perceived dangerousness, are known to elicit high levels of physiological and psychological arousal. It has become apparent that food rejections by both children and adults are frequently linked to such arousal-inducing characteristics. This paper examines how arousal and arousability are important elements in responding to stimuli generally, but specifically to foods, ultimately influencing food preferences and choices. It is clear that responses to sensory properties are subject not just to variations in perceptual sensitivity due to genetics or experience-as in the case of widely rejected qualities such as bitterness or pungency-but also to the arousal potential of those stimuli. Moreover, this is linked to various enduring aspects of personality, suggesting that the impact of arousal on food choices is merely one aspect of a more general sensory sensitivity. The impact of diet on various health outcomes underlines the importance of understanding the relationship of arousal to food choices. This article is part of the theme issue 'Sensing and feeling: an integrative approach to sensory processing and emotional experience'.

A matter of personality and point of view: How the interplay of reinforcement sensitivity and general attitudes towards pain impacts the responsivity to acute pain

BACKGROUND

The relatively stable individual differences reflected in Grey's revised reinforcement sensitivity theory (rRST), with foundations in neurophysiology and learning theory, appear particularly applicable to the study of pain. However, remarkably little research has been conducted in this area. In acute pain, activation of the behavioural approach system (BAS), the behavioural inhibition system (BIS) and the fight, flight, freezing system might depend on an individual's evaluation of pain. It was thus hypothesised that higher-order interactions of rRST traits and pain attitudes affect pain responsiveness.

METHODS

To investigate relationships between rRST traits and pain attitudes and to identify patterns between clusters of participants, we conducted a study in which N = 275 healthy participants filled in Reuter and Montag's rRST-Q and the General Attitudes Towards Pain Inventory (GATPI). Experimental (pressure, electrical, thermal) and self-report data of pain responsiveness were collected in a subsample (N = 113).

RESULTS

We found significant correlations between rRST-Q and GATPI subscales of up to r = 0.34. Two clusters were identified, significantly differing in rRST-Q and GATPI scores. Pain avoiders, characterized by high BIS, flight, freezing and negative pain attitudes, were found to be significantly more pain sensitive than pain approachers, characterized by high BAS, fight and positive pain attitudes. Moderate effects (d = 0.56 to d = 0.70) were demonstrated in subjective and objective measures and across pain modalities.

CONCLUSIONS

The present study expands the scientific knowledge on factors influencing pain responsiveness. Future research is needed to confirm implications for chronic pain prevention and therapy, particularly concerning pain avoiders.

SIGNIFICANCE

We have identified two clusters of participants, pain avoiders and pain approachers, that not only present differential patterns of revised reinforcement theory traits and general attitudes towards pain but also differ in their pain responsiveness. Pain avoiders appeared more pain sensitive compared to pain approachers, both in objective and subjective measurements, with implications for the improvement of chronic pain prevention and therapy.

Uncontrolled eating is associated with higher impulsiveness, risk taking and novelty-seeking

Previous studies suggest that trait disinhibition as measured by the Three Factor eating Questionnaire (TFEQ) is related to selected measures of impulsivity and risk taking. However, the factor validity of the original trait disinhibition measure has been questioned, and a revised scale of uncontrolled eating consequently developed. To date few studies have revisited the relationship between impulsivity and the uncontrolled and emotional eating scales of the revised TFEQ. In the present study, 283 participants (208 women) completed the revised TFEQ alongside a battery of measures of impulsivity and risk taking in an online study. The total and all subscale scores on the Barratt Impulsiveness Scale were significantly associated with scores on the uncontrolled, but not emotional or restrained, TFEQ scale. Likewise, risky behaviour indexed by the average number of pumps per trial on the Balloon Analogue Risk Task were also associated with uncontrolled, but not emotional or restrained, eating, and the same pattern of associations were also found for the novelty, but not intensity, subscales of the Arnetts Inventory of Sensation Seeking. Overall these data suggest that uncontrolled eating is related to wider personality traits of risky decision making, novelty seeking and wider cognitive impulsivity, which may in turn increase of future weight gain.

Spice up the moment: The influence of spicy taste on people's metaphorical perspectives on time

Embodied cognition contends that sensorimotor experiences undergird cognitive processes. Three embodied cross-domain metaphorical mappings constitute quintessential illustrations: spatial navigation and orientation underpin the conceptualization of time and emotion and gustatory sensation underlies the formulation of emotion. Threading together these strands of insights, the present research consisted of three studies explored the potential influence of spicy taste on people's metaphorical perspectives on time. The results revealed a positive correlation between spicy taste and the ego-moving metaphor for time such that individuals who enjoyed spicy taste (Study 1) and who consumed spicy (vs. salty) snack (Study 2) exhibited a predilection for the ego-moving perspective when cognizing a temporally ambiguous event. Because both spicy taste and the ego-moving metaphor are associated with anger and approach motivation, the latter two were postulated to be related to the novel taste-time relationship. Corroborative evidence for the hypothesis was found, which indicated that spicy (vs. salty) intake elicited significantly stronger anger toward and significantly greater approach-motivated perception of a rescheduled temporal event (Study 3). Taken together, the current findings demonstrate that spicy taste may play a role in people's perspectives on the movement of events in time and highlight the involved embodied interrelation between language, emotion, and cognition.

Sensory Perception and Food-Evoked Emotions of Older Adults Assessing Microwave-Processed Meals with Different Salt Concentrations

This study employed a home-use test to explore the sensory perception and evoked emotions of older adults in the assessment of chicken pasta meals with different salt concentrations. Ready-to-eat (RTE) meals with three salt levels (100%, 75%, and 50%) and two treatments-with and without added herbs-were tested. Multiple sensory attributes and overall meal liking were evaluated by participants (n = 54; 60-86 years of age) with hedonic and just-about-right scores. Twenty-five food-evoked emotions were also tested. Sensory results suggested a 50% salt reduction is possible with minimal impact on the overall liking, while a 25% salt reduction did not affect the saltiness and flavor liking of the meals. Herb addition positively impacted the aroma, flavor, and spiciness liking of the meals. The emotions that differed (p < 0.05) among meals were active, aggressive, bored, calm, happy, and wild, with the meals with herbs added eliciting more positive emotions. A questionnaire elicited information about participants' interest in healthy eating, food technology neophobia, and picky behaviors to determine the influence of these factors on participants' salt consumption habits. Sensory acceptance data combined with questionnaires explored what influenced this group of older adults in their acceptance of and interest in RTE meals.

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.

Cultural inclusion and corporate sustainability: evidence from food culture and corporate total factor productivity in China

This article constructed a food taste deviation index using text analysis based on food culture as a measure of cultural inclusion. Cultural inclusion was related to corporate total factor productivity, aiming to investigate whether the cultural inclusion affects corporate sustainability. The findings showed uneven distribution of cultural inclusion in various areas of China, contributing to the unbalanced sustainable development of firms in different regions, as reflected by the higher total factor productivity of firms located in regions with higher cultural inclusion. A test using mountainous undulation as an instrumental variable verified the causal relationship between cultural inclusion and firm sustainability. Besides, a regression discontinuity design was employed to mitigate the impacts of the bidirectional causality. Moreover, a high level of cultural inclusion in top managers' hometown significantly improved corporate sustainability, suggesting that executives can transmit cultural inclusion in society. In addition, firms in more inclusive regions are more motivated to increase their social responsibility to staff as a way to promote their total factor productivity, suggesting that cultural inclusion promotes firm sustainability by increasing firms' care for staff. This article also found that cultural inclusion has heterogeneous effects across firms of different levels of industry competition, and different levels of analyst attention. The research reveals the impact of cultural inclusion on the real economy and help academics dissect the informal institutional reasons behind the sustainable development of firms in different geographies from a new perspective, contributing to the promotion of economic sustainability at the regional level and related policy formulation.

The contribution of subliminal perceptions, dietary habits, and psychological traits to the perception of oral tingling and burning sensations

The tingling evoked by Sichuan pepper and the burning elicited by chili pepper constitutes the typical flavor of Sichuan cuisine and is a component of leisure food. Although factors affecting the burning sensation have extensively been studied, few studies have examined the factors of individual sensitivity, personality traits, and dietary habits that contribute to the perception of oral tingling sensation, which hinders the formulation of tingling products and the development of new products. In contrast, many studies have examined the factors influencing the burning sensation. In this web-based survey, 68 participants disclosed their dietary habits, liking for tingling and hot foods, and psychological traits. Individual sensitivity to the tingling and burning sensation produced by a range of Sichuan pepper oleoresin and capsaicin solutions was determined using rated differences from control, generalized labeled magnitude scale method and ranking test. The consistency score indicated the accuracy of individual ranking results while also providing an indirect response to the sensitivity of the participant to supra-threshold for burning or tingling. Individual ratings for medium Sichuan pepper oleoresin concentrations significantly correlated with the just noticeable difference (p < 0.01), and ratings for medium and high capsaicin concentrations correlated significantly with 6-n-propylthiouracil ratings (p < 0.01). Notably, the power exponent of burning was significantly correlated with the burning recognition threshold (p < 0.01), and the power exponent of tingling and burning were significantly correlated (r = 0.340, p < 0.05). There was a negative correlation between supra-threshold tingling and burning sensation perceptions and life satisfaction ratings. Further, intensity ratings for oral tingling and burning sensation did not always correspond with individual sensitivity indicators (e.g., recognition threshold, 6-n-propylthiouracil, just noticeable difference, and consistency score). Thus, this study provides new insight into establishing a sensory selection method for chemesthetic sensation panelists and theoretical guidelines for formulation design and in-depth analysis of popular tingling dishes and foods.

Sourness impacts envy and jealousy in Chinese culture

In the present study, five experiments (N = 233) were designed to explore whether sourness as a sensory experience could implicitly impact social emotions of envy and jealousy in Chinese culture. Experiment 1 (n = 63) explored the implicit conceptual association between sourness words (vs. bitterness words) and envy/jealousy words. Experiment 2 (n = 70) and 3 (n = 20) examined the priming effects of imagined and tasted sourness (vs. bitterness and sweetness) on self-rated emotional intensity in envy- and jealousy-arousing situations, respectively. Experiment 4 (n = 40) and 5 (n = 40) further testified the priming effects of imagined and tasted sourness (vs. bitterness and sweetness) on self-rated emotional intensity in four types of social situations (i.e., envy, jealousy, sad and happy events), respectively. In the results, sourness was found as the only taste that not only conceptually associated with envy/jealousy, but also significantly primed envy/jealousy feelings. The possible mechanism underlying the association of sourness-envy/jealousy was discussed.

Effect of Piperine on Saltiness Perception

Chemical irritants, like piperine, have the potential to increase human perception of tastes and odours, including saltiness. This cross-modal interaction could help the food industry develop new salt-reduced food products that maintain their salty taste. The objective of this study was: firstly, to determine the detection threshold of piperine (n = 72), secondly to evaluate piperine's influence on saltiness perception in model solutions (n = 78), and lastly to identify piperine's effect on sensory perception of low sodium soup using temporal check-all-that-apply (TCATA; n = 75). The group mean of the individual threshold was 0.55 ± 0.15 ppm. Piperine increased the saltiness perception of the model solutions, but it also increased the bitterness and decreased the sweetness of the solutions. The piperine significantly increased the saltiness intensity of the soups (evaluated using a generalized labelled magnitude), but during the TCATA task, the salty attribute was selected less for the soup with piperine than the control (based on the average proportion of selection). The TCATA indicated that the peppery attribute dominated the participants' perception of the soup with piperine. More studies are needed to assess piperine's cross-modal interactions.

Getting hot: Effect of chili pepper addition on sensory perception of liquid and solid foods

The impact of trigeminal oral burn and pungency on taste, flavor, and mouth-feel perception of commercially available foods is underexplored. This study aimed to determine the effect of oral burn sensations evoked by the addition of chili powder to tomato soup, beef burger patties, and curried rice on taste, flavor, and mouth-feel perception. Chili powder was added to tomato soups, beef burger patties, and curried rice at four concentrations. A consumer panel comprising n = 66 participants (49 women, 25.5 ± 5.8 years, BMI 22.9 ± 2.8 kg/m² ) assessed taste, flavor, trigeminal, and mouth-feel intensity of all samples using Rate-All-That-Apply methodology. Food matrix consistency strongly impacted oral burn sensations with solid food matrices (beef burger patties and curried rice) suppressing oral burn intensity compared to liquid food matrices (tomato soup). With increasing oral burn intensity, perceived intensity of beef flavor decreased significantly for beef burger patties. Tomato flavor, sweetness, and sourness intensity decreased significantly with increasing oral burn intensity for tomato soups. Perceived burn intensity of all food matrices and beef flavor intensity of beef burger patties differed between infrequent and frequent chili pepper consumers. We conclude that increasing oral burn intensity by the addition of chili pepper powder led to only small reductions in taste and flavor intensity of tomato soups and to little or no changes in flavor and mouth-feel perception of beef burger patties and curried rice. We suggest that reductions in taste, flavor, and mouth-feel intensity caused by oral burn might be more pronounced in liquid (tomato soup) than solid foods (beef burger patties and curried rice). PRACTICAL APPLICATION: There is a growing public and scientific interest in the development of strategies to increase the sensory appeal of healthy foods and beverages. Incorporation of trigeminal stimuli, such as chili peppers or capsaicin (pungent component of chili peppers), can be a strategy to increase sensory appeal of foods and beverages. Little is known about how trigeminal oral burn and pungency influence taste, flavor, and mouth-feel perception of commercially available foods, although it has been well established that taste, flavor, mouth-feel, and trigeminal sensations contribute to product acceptance. By investigating the sensory impact of oral burn on flavor and mouth-feel perception of foods, this study may help to better understand how trigeminal stimuli can be applied to moderate flavor and mouth-feel perception of foods to optimize sensory appeal.

Chili pepper preference development and its impact on dietary intake: A narrative review

A preference for chili pepper can be an acquired taste. The contrast between a chili lover and a hater illustrates the complexities involved in forming an appreciation for food that evokes a fiery pain sensation. This narrative review aims to understand the factors behind chili pepper preference formation across the life course and how individual chili pepper preferences can impact eating behaviors and dietary intake. This review was conducted using three databases, yielding 38 included articles. Results suggest five determinants of chili pepper preferences: culture, exposure, gender, genetics, and personality. Collective findings indicate that the strongest influences on preference acquisition include the individual environment from childhood to adulthood and repeated exposure to spicy flavors. With frequent exposure to spicy food, the perceived burn becomes less intense. Culture also influences exposure to chili peppers, with the highest consumption patterns seen within Mexico and some Asia countries. Additionally, males reported having a stronger preference for spicy foods than females. Twin studies illustrated that genetics influenced spicy taste preferences, underscoring the complexity of developing individual taste preferences. As for the impact of capsaicin-containing food on individual eating behaviors and dietary behaviors, appetite effects depend on the dose of capsaicin consumed, but three studies found a change in sensory desires for sweet and fatty foods after finishing a capsaicin-containing dish. Inconsistent results were reported for chili pepper's effects on hunger and satiety after consumption, but changes in specific food desires were observed. The impact of chili pepper on appetite and calories consumed was inconsistent, but the greater amount of capsaicin ingested, the greater the effect. Capsaicin's potential to be used for weight control needs to be further reviewed. In conclusion, evidence suggests that chili pepper preferences may be linked to innate and environmental aspects such as an individual's culture, gender, and genetics. Extrinsic factors like repeated exposure may increase the liking for spicy foods.

The effect of dairy proteins on the oral burn of capsaicin

This study focused on the effect of binding of capsaicin by milk proteins on oral burn. The concentration of free, unbound capsaicin in 5 ppm capsaicin solution containing 0-5% (w/w) micellar casein or whey protein isolate was measured by extraction into hexadecane. The concentration of free capsaicin decreased linearly with protein concentration and the decrease was greater for casein than for whey protein. The intensity of the capsaicin burn in similar solutions was assessed by a large cohort (n = 89) of untrained participants in a time-intensity study. The maximum burn intensity decreased with protein concentration and was lower for samples containing casein than for samples containing whey protein isolate. The maximum burn was linearly related to the free, unbound capsaicin concentration. When protein solutions (1-5% w/w) were used as rinses following exposure to a 5 ppm aqueous capsaicin solution, only the 5% (w/w) micellar casein solution was significantly more effective than the water rinse in reducing oral burn.

Dietary Capsaicin: A Spicy Way to Improve Cardio-Metabolic Health?

Today's sedentary lifestyle with too much food and too little exercise has made metabolic syndrome a pandemic. Metabolic syndrome is a major risk factor for type-2 diabetes and cardiovascular disease. New knowledge of medical and nutraceutical intervention in the early stages of metabolic syndrome is central to prevent these deadly complications. People who eat chili pepper on a regular basis seem to stay healthier and live longer than those who do not. Animal experiments suggest a therapeutic potential for dietary capsaicin, the active principle in hot chili pepper, to reduce the risk of developing metabolic syndrome. This is an attractive theory since capsaicin has been a culinary staple for thousands of years, and is generally deemed safe when consumed in hedonically acceptable doses. The broad expression of the capsaicin receptor TRPV1 in metabolically active tissues lends experimental support to this theory. This review critically evaluates the available experimental and clinical evidence for and against dietary capsaicin being an effective dietary means to improve cardio-metabolic health. It comes to the conclusion that although a chili pepper-rich diet is associated with a reduced risk of dying due to cardiovascular disease, dietary capsaicin has no clear effect on blood glucose or lipid profiles. Therefore, the reduced mortality risk may reflect the beneficial action of digested capsaicin on gut microbiota.

Emotional responses to taste and smell stimuli: Self-reports, physiological measures, and a potential role for individual and genetic factors

Taste and olfaction elicit conscious feelings by direct connection with the neural circuits of emotions that affects physiological responses in the body (e.g., heart rate and skin conductance). While sensory attributes are strong determinants of food liking, other factors such as emotional reactions to foods may be better predictors of consumer choices even for products that are equally-liked. Thus, important insights can be gained for understanding the full spectrum of emotional reactions to foods that inform the activities of product developers and marketers, eating psychologist and nutritionists, and policy makers. Today, self-reported questionnaires and physiological measures are the most common tools applied to study variations in emotional perception. The present review discusses these methodological approaches, underlining their different strengths and weaknesses. We also discuss a small, emerging literature suggesting that individual differences and genetic variations in taste and smell perception, like the genetic ability to perceive the bitter compound PROP, may also play a role in emotional reactions to aromas and foods.

Food Culture and Sustainable Development: Evidence from Firm-Level Sustainable Total Factor Productivity in China

This article studied whether food culture plays an important role in affecting the firm-level sustainable development. We linked firm-level sustainable total factor productivity to spicy-taste related food culture in China and found that firms in regions in which spicy culture plays a more prominent role showed higher sustainable productivity. Tests using the regional sunshine as an instrument suggested a causal interpretation. Moreover, firms more exposed to spicy culture showed more frequent equity incentive behavior, higher equity incentive intensity, and higher proportion of female executives, which suggests that the more proactive management behavior can be led by regional spicy culture. We also found that, compared with small-size firms, non-state-owned firms, and non-export firms, regional spicy culture has a stronger impact on large firms, state-owned firms, and export firms. Our results reveal the impact of food culture on the firm-level sustainable development.

Effects of Tasting and Ingredient Information Statement on Acceptability, Elicited Emotions, and Willingness to Purchase: A Case of Pita Chips Containing Edible Cricket Protein

Sustainable and nutritious alternatives are needed to feed the ever-increasing world population. The successful incorporation of edible-cricket protein (ECP) into foods needs deeper consumer insights. Treatments (plain, Italian, and Cajun pita chips containing 6.9% w/w ECP) were evaluated by subjects for overall liking (OL), emotions, and purchase intent (PI) in three different moments: (1) before tasting, (2) after tasting/before ECP statement, and (3) after tasting/after ECP statement. Attributes’ liking scores were evaluated only after tasting/before ECP statement. Liking scores (mixed-effects ANOVA), emotions, and PI across moments within treatments/across treatments within moments were evaluated. Emotion-based penalty-lift analyses for OL within moments were assessed using two-sample t-tests (p < 0.05). Random forest model analyzed after-tasting informed PI and variables’ importance. Although formulations’ OL and PI were similar across moments, plain and Italian chips had higher after-tasting (before and after ECP statement) OL than the Cajun chips. Moments indirectly affected OL via emotions elicitation. Valence and activation/arousal emotions discriminated across moments for the plain treatment whereas valence and mostly activation/arousal terms discriminated across moments for the Italian and Cajun treatments, respectively. For either formulation or moment, “interested” and “adventurous” positively affected OL. Before and after-tasting attribute liking, “satisfied,” and “enthusiastic” emotions were critical in predicting after-tasting informed PI.

Parsing the link between reinforcement sensitivity theory and eating behavior: A systematic review

The Reinforcement Sensitivity Theory (RST) is a widely studied psychobiological model of personality. RST factors seem to influence eating behavior, but how these personality traits are associated with distinct features of eating behavior is still unclear. In the present systematic review, we analyzed the relationship between RST personality factors and eating behavior using a parsing approach in which BMI-related results, self-reported results, and behavioral results were distinguished. Our analysis revealed that reward and punishment sensitivity seem to correlate and influence distinct features of eating behavior. The association between BMI and RST factors was uncertain, but nonlinear associations between reward sensitivity and weight need further testing. Reward sensitivity was linked to most eating behavior phenotypes (e.g., emotional eating and restrained eating), but only punishment sensitivity was primarily correlated with eating pathology. Reward sensitivity was the main factor linked with reactivity to food stimuli on many behavioral measures. The neurobiological personality factors of RST offer parsimonious concepts to understand eating behavior outcomes and the differential relationships observed are useful to translational research.

What is the link between personality and food behavior?

A number of personality characteristics have been linked to various aspects of taste (gustation), trigeminal, and olfactory perception. In particular, personality traits have been linked to olfactory sensory thresholds and olfactory identification abilities, as well as to the sensory-discriminative aspects of taste/flavour perception. To date, much of the research in this area has focused on Sensation Seeking (including Experience Seeking, and Openness to Novel Experiences), with the latter being linked to a preference for spicy, and possibly also crunchy, sour, and bitter foods/drinks. Novelty-seeking has also been linked to a preference for salty foods, while anxious individuals appear to enjoy a much narrower range of foods. A bidirectional link has also been documented between taste and mood. Certain of the personality-based differences in taste/flavour perception and food behaviour have been linked to differences in circulating levels of neurotransmitters and hormones in both normal and clinical populations. Taken together, therefore, the evidence that has been published to date supports a number of intriguing connections between personality traits and taste perception/food behaviour.

Political taste: Exploring how perception of bitter substances may reveal risk tolerance and political preferences

Risk is endemic to the political arena and influences citizen engagement. We explore this connection by suggesting that risk-taking may be biologically instantiated in sensory systems. With specific attention to gender and gender identity, we investigate the connections between self-reported bitter taste reception, risk tolerance, and both of their associations with political participation. In three U.S. samples collected in 2019 and 2020, participants were asked to rate their preferences from lists of foods as well as whether they detected the taste of the substance N-Propylthiouracil (PROP) and, if so, the strength of the taste. In this registered report, we find that self-reported bitter taste preference, but not PROP detection, is positively associated with higher levels of risk tolerance as well as political participation. The pattern with gender and gender identity is mixed across our samples, but interestingly, we find that sex-atypical gender identity positively predicts political participation.

Capsaicin burn increases thickness discrimination thresholds independently of chronic chili intake

The trigeminal nerve transduces both chemical irritation and textural sensations suggesting that perception in one may influence perception in the other. Little is known about how the oral burn of capsaicin may affect texture sensitivity. The aim of this study was to determine the effect of burning sensations on thickness discrimination thresholds in liquid foods assessed by consumers who vary in habitual spicy food intake. Forty-seven Caucasian participants (31 females and 16 males; mean age: 25.0 ± 5.7 yrs; mean BMI: 21.5 ± 2.6 kg/m²) were recruited in the Netherlands. Chili pepper intake frequency and preference for chili peppers and spicy foods were assessed using questionnaires. Perceived burn and disliking/liking of bouillon soups thickened with xanthan gum (concentrations ranging from 0.06 to 0.21 g/mL; viscosity at 50 s^-1 (η_50s-1) ranging from 11 to 48 mPas) containing varying amounts of capsaicin (0, 1, or 10 ppm) were determined using generalized scales (gLMS and gDOL). Estimates of thickness discrimination thresholds were determined using the 2-Alternative Forced Choice ascending staircase method. Capsaicin was applied in two ways: (i) capsaicin was added directly to the soups or (ii) a pre-rinse of a capsaicin solution was held in mouth before evaluating soups without capsaicin. As expected, frequent chili pepper consumers reported significantly lower burn intensity and higher hedonic ratings compared to infrequent consumers. Thickness discrimination thresholds (i.e., BET expressed as Δη_50s-1) increased significantly from 11.3 mPas at 0 ppm to 16.1 mPas at 1 ppm (42% increase) to 21.4 mPas at 10 ppm capsaicin (89% increase) on average across all participants. Similar modification of thickness discrimination thresholds were observed regardless of whether capsaicin was added to the soup or was applied as a pre-rinse. No significant differences in thickness discrimination thresholds were observed between infrequent and frequent chili consumers. We conclude that oral burn caused by capsaicin affects thickness discrimination independently of reported chili pepper intake. Also, we suggest the ability of capsaicin to alter thickness discrimination may be due to increased neural noise, attentional effects or cross-modal interactions.

Is it still still water? Relationships between sparkling sensitivity and consumption frequency of carbonated waters

Little is known about how sensitivity to trigeminal stimulation such as carbonation is affected by consumption habits and consumer characteristics. The aim of this study was to determine how detection thresholds for and perception of sparkling sensations in carbonated mineral water are affected by frequency of consumption of carbonated water and individual consumer characteristics. One hundred subjects differing in sparkling water consumption frequency (non-consumers, infrequent consumers, frequent consumers) participated. First, sparkling sensation detection thresholds were determined using the method of best estimate threshold (BET) with CO₂ concentrations ranging from 0.03 to 1.05 g/L. Secondly, intensity of sparkling sensation and liking of five sparkling waters (CO₂ concentrations ranging from 0.21 to 4.92 g/L) were assessed. To characterize consumers, consumption frequency of sparkling water, sensitivity to 6-n-propylthiouracil (PROP taster status) and consumer characteristics were determined. Average detection threshold of sparkling sensation (BET) was 0.44 g/L CO₂ concentration. BET of sparkling sensation was not affected by consumption frequency of sparkling water and was not related to PROP taster status and consumer characteristics. Perception of sparkling intensity and liking of carbonated mineral water were significantly affected by consumption frequency of sparkling water. Sparkling sensations were perceived significantly more intensive by non-consumers compared to infrequent and frequent consumers. Surprisingly, non-consumers liked sparkling water significantly more than infrequent or frequent consumers. We conclude that consumption frequency of and preferences for carbonated water do not influence detection thresholds of sparkling sensations but influence suprathreshold intensity perception of sparkling sensations in carbonated water.

Phenol-Rich Food Acceptability: The Influence of Variations in Sweetness Optima and Sensory-Liking Patterns

The consumption of phenol-rich foods is limited by their prominent bitterness and astringency. This issue has been addressed by adding sweet tastes, which suppress bitterness, but this is not a complete solution since individuals also differ in their preference for sweetness. In this study, we aimed at identifying groups of consumers differing in sweetness optima and sensory-liking patterns. To this end, increasing concentrations of sucrose were added to a chocolate pudding base. This allowed us to (1) investigate if individual differences in sensory responses are associated with different sweet liking optima in a product context, (2) define the psychological and oro-sensory profile of sweet liker phenotypes derived using a product context, and (3) assess if individuals differing in sweet liking optima differ also in consumption and liking of phenol-rich foods and beverages as a function of their sensory properties (e.g., sweeter vs. more bitter and astringent products). Individuals (1208; 58.4% women, 18–69 years) were characterised for demographics, responsiveness to 6-n-propylthiouracil (PROP), personality traits and attitudes toward foods. Three clusters were identified based on correlations between sensory responses (sweetness, bitterness and astringency) and liking of the samples: liking was positively related to sweetness and negatively to bitterness and astringency in High and Moderate Sweet Likers, and the opposite in Inverted U-Shaped. Differences between clusters were found in age, gender and personality. Furthermore, the Inverted-U Shaped cluster was found to have overall healthier food behaviours and preferences, with higher liking and consumption of phenol-rich vegetables and beverages without added sugar. These findings point out the importance of identifying the individual sensory-liking patterns in order to develop more effective strategies to promote the acceptability of healthy phenol-rich foods.

Some like it hot: Preference for temperature and pungency consumption is associated with sensitivity to noxious heat

BACKGROUND

Individuals vary in their temperature and pungency preferences; whereas some individuals prefer to bath in, or consume food and beverages at very high temperatures, others prefer lukewarm temperatures. Similarly, pungent food may be preferred by some, but not by others. The aim was to investigate, for the first time whether temperature and pungency preferences are associated with variations in thermal sensitivity or ethnic origin related to pungency consumption.

METHODS

115 healthy volunteers participated. The thresholds for warm (WST) and heat-pain (HPT) sensations were measured over the tongue and dorsal hand, and the participants' preferred drinking and bath temperatures were measured. In addition, data on the participants' ethnic background as well as temperature and pungency preferences and household habits regarding eating, drinking and bathing were collected.

RESULTS

The reported drinking and bathing preferences correlated significantly with the measured drinking and bath temperatures, respectively, validating subjects' reports. Tongue and hand HPT, but not WST, correlated with both the reported and the measured drinking and bathing preferences, as well as with pungency preferences. Neither ethnic origin nor gender affected HPT or temperature preferences; however, males preferred a greater level of spiciness than females.

CONCLUSIONS

The association of the reported and measured preferences with noxious heat sensitivity in both relevant and irrelevant body regions, and lack of an ethnicity effect may suggest that these qualities are innate. The association of HPT and spiciness preferences correspond with the mutual activation of the tongue vanilloid receptors by noxious heat and capsaicin.

SIGNIFICANCE

People vary with regard to their temperature and spiciness preferences for reasons yet unknown. The study revealed that these preferences correlate with one another and were associated with the sensitivity to noxious heat but not with age, gender and cultural background, which suggests that they may be innate.

The Dessert Flip: Consumer preference for desserts with a high proportion of fruit and nuts

American adults consume excess added sugar and saturated fat, and not enough fruit. A possible solution is the "Dessert Flip," a shift in which the proportions of more sustainable plant-based garnishes, such as fruit and nuts, are increased, while the proportion of conventional dessert is reduced. We hypothesized that the pleasing properties of fruits and nuts-color, variety, flavor, and texture-would allow the Dessert Flip to be liked as well or better than a conventional dessert by college-aged students in a dining hall. In a sensory test, participants (n = 118) significantly preferred plated flipped desserts-those containing 80% by weight fruit (strawberries, raspberries, blueberries, and mangoes) and nuts with 20% cake-over the conventional versions of those desserts with 80% cake and 20% fruit and nuts. No significant differences were found in overall liking. In a second experiment, after eating an entrée, participants (n = 150) chose pictures of multiple varieties of flipped cakes with 60% fruit and 40% cake significantly more than pictures of conventional 80% cake for dessert. Based on the U.S. average fruit prices, the Dessert Flip can be equal or lower in price per serving compared to an ungarnished typically sized cake. We conclude that the Dessert Flip offers a feasible option for increasing servings of fruits and nuts in desserts as well as reducing added sugar and saturated fat while maintaining sensory appeal. Future dietary guidelines could include this general strategy as a recommendation for helping adults include more fruits in their diets. PRACTICAL APPLICATION: The Dessert Flip offers an appetizing way for foodservice to promote healthier eating by increasing servings of fruits and nuts in their desserts while reducing added sugar and saturated fat. Consumers can try this strategy at home by cutting a smaller piece of cake and adding fruit on the side.

Effects of Sweet-Liking on Body Composition Depend on Age and Lifestyle: A Challenge to the Simple Sweet-Liking-Obesity Hypothesis

Taste hedonics drive food choices, and food choices affect weight maintenance. Despite this, the idea that hyper-palatability of sweet foods is linked to obesity development has been controversial for decades. Here, we investigate whether interpersonal differences in sweet-liking are related to body composition. Healthy adults aged 18–34 years from the UK (n = 148) and the US (n = 126) completed laboratory-based sensory tests (sucrose taste tests) and anthropometric measures (body mass index; BMI, body fat; fat-free mass; FFM, waist/hips circumferences). Habitual beverage intake and lifestyle and behavioural characteristics were also assessed. Using hierarchical cluster analysis, we classified participants into three phenotypes: sweet liker (SL), sweet disliker (SD), and inverted-U (liking for moderate sweetness). Being a SD was linked to higher body fat among those younger than 21 years old, while in the older group, SLs had the highest BMI and FFM; age groups reflected different levels of exposure to the obesogenic environment. FFM emerged as a better predictor of sweet-liking than BMI and body fat. In the older group, sweetened beverage intake partially explained the phenotype–anthropometry associations. Collectively, our findings implicate underlying energy needs as an explanation for the variation in sweet-liking; the moderating roles of age and obesogenic environment require additional consideration.

Do Caucasian American and South Asian Indian cultural groups differ in sensitivity to capsaicin? A study designed to control for chili pepper affinity

Although different cultural groups are known to vary in their tolerance for hot chili peppers, the influence of factors such as cultural background and upbringing on sensitivity to compounds in spicy food is unclear. A study was designed to investigate sensitivity differences to capsaicin between Caucasian American and South Asian Indian cultural groups while controlling for general chili pepper affinity. The two cultural groups were selected to match on metrics related to chili pepper use and liking. Subjects were exposed to a capsaicin (100 ppm) stimulus on the tongue, cheek, hard palate, and lip and rated the intensity of irritation every 30 s, over a 10-min period. Overall sensitivity to capsaicin in the oral cavity did not differ between the groups, nor were responses different between the groups depending on the oral cavity area stimulated. These data suggest a limited role of cultural attributes on capsaicin sensitivity between Caucasian Americans and South Asian Indians. The methods and findings here provide subject recruitment insight and guidance on effectively designing a sensory study to answer perceptual questions regarding specific subject groups. PRACTICAL APPLICATION: This study design provides a model for researchers interested in utilizing sensory testing to answer questions about subject groups. Although the objective of this study regarded sensitivity differences across two cultural groups, alterations in the subject matching process used presently could be easily implemented to investigate sensitivity across other differing subject characteristics of interest.

Discrimination of Isointense Bitter Stimuli in a Beer Model System

Prior work suggests humans can differentiate between bitter stimuli in water. Here, we describe three experiments that test whether beer consumers can discriminate between different bitterants in beer. In Experiment 1 (n = 51), stimuli were intensity matched; Experiments 2 and 3 were a difference from control (DFC)/check-all-that-apply (CATA) test (n = 62), and an affective test (n = 81). All used a commercial non-alcoholic beer spiked with Isolone (a hop extract), quinine sulfate dihydrate, and sucrose octaacetate (SOA). In Experiment 1, participants rated intensities on general labeled magnitude scales (gLMS), which were analyzed via ANOVA. In Experiment 2, participants rated how different samples were from a reference of Isolone on a 7-point DFC scale, and endorsed 13 attributes in a CATA task. DFC data were analyzed via ANOVA with Dunnett's test to compare differences relative to a blind reference, and CATA data were analyzed via Cochran's Q test. In Experiment 3, liking was assessed on labeled affective magnitude scales, and samples were also ranked. Liking was analyzed via ANOVA and rankings were analyzed with a Cochran-Mantel-Haenszel test. Experiment 1 confirmed that samples were isointense. In Experiment 2, despite being isointense, both quinine (p = 0.04) and SOA (p = 0.03) were different from Isolone, but no significant effects were found for CATA descriptors (all p values > 0.16). In Experiment 3, neither liking (p = 0.16) or ranking (p = 0.49) differed. Collectively, these data confirm that individuals can discriminate perceptually distinct bitter stimuli in beer, as shown previously in water, but these differences cannot be described semantically, and they do not seem to influence hedonic assessments.

Association of the frequency of spicy food intake and the risk of abdominal obesity in rural Chinese adults: a cross-sectional study

OBJECTIVES

Recent data relating to the association between spicy food intake frequency and abdominal obesity are limited, especially in low-income areas. Therefore, the study explored the relationship between spicy food intake frequency and abdominal obesity, and assessed the role of energy intake as a mediator of these associations in a rural Chinese adult population.

DESIGN

Cross-sectional study.

SETTING

Rural Chinese adult population.

PARTICIPANTS

Subjects from Henan Rural Cohort Study (n=28 773).

PRIMARY OUTCOME MEASURES

The effects of spicy food intake frequency on abdominal obesity were analysed by restricted cubic spline and logistic regression, and the mediation effect was analysed using the bootstrap method.

RESULTS

The adjusted percentages of abdominal obesity were 47.32%, 51.93%, 50.66% and 50.29% in the spicy food intake subgroups of never, 1-2 day/week, 3-5 day/week and 6-7 day/week, respectively. An inverse U-shaped association was found between spicy food intake frequency and abdominal obesity (p<0.01). Compared with subjects who never consumed spicy food, the adjusted ORs (95% CIs) in the 1-2 day/week, 3-5 day/week and 6-7 day/week subgroups were 1.186 (1.093, 1.287), 1.127 (1.038, 1.224) and 1.104 (1.044, 1.169), respectively. Furthermore, the increased odd of abdominal obesity related to more frequent spicy food intake was mediated by higher fat energy intake; the direct and indirect effects were 1.107 (1.053, 1.164) and 1.007 (1.003, 1.012), respectively.

CONCLUSIONS

The data indicated that spicy food intake increased the risk of abdominal obesity, and fat energy intake may be a mediator of this association in rural Chinese populations. Clarifying the mechanisms will facilitate the development of novel preventive and therapeutic approaches for abdominal obesity.

TRIAL REGISTRATION NUMBER

ChiCTR-OOC-15006699.

Individual differences in the perception of orthonasal irritation induced by food

Oral responsiveness to the burning/spicy sensation affects food behaviors and diet; therefore, it is reasonable to hypothesize that the variation in nasal responsiveness to irritant foods may play a role in modulating food behaviors. This study explored the variation among individuals in orthonasal irritation induced by smelling food ingredients containing irritant compounds: mustard oil (2.0, 10.0, and 100.0% v/v mustard oil in corn oil; irritant compound: allyl isothiocyanate); vinegar (3.5, 42.3, and 98.6% v/v vinegar in water; irritant compound: acetic acid); and wasabi (0.1, 0.2, and 0.4% w/w wasabi powder in water; irritant compound: allyl isothiocyanate). Sixty-eight subjects (40% males; 19-87 years) smelled the nine samples and rated their perceived intensity of odor, irritation and liking. Wide individual variation in the perception of irritation and odor intensity was found, especially at the highest concentrations. Young individuals were the most sensitive to all stimuli. No significant differences were found between males and females. Fifty-seven percent of subjects were "HYPO" and 43 percent "HYPER" responsive to irritation, respectively. Perceived irritation was positively correlated with odor intensity and tended to be negatively correlated with liking, especially in familiar stimuli. The results suggest that the variation in nasal responsiveness to irritant foods may contribute to influencing food acceptance and therefore, to modulating food behaviors.

Putting out the fire - Efficacy of common beverages in reducing oral burn from capsaicin

Capsaicin is classically considered an irritant, due to the warming and burning sensations it elicits. Widespread consumption of chilis suggests many individuals enjoy this burn, but these sensations can be overwhelming if the burn is too intense. While substantial folklore exists on the ability of specific beverages to mitigate capsaicin burn, quantitative data to support these claims are generally lacking. Here, we systematically tested various beverages for their ability to reduce oral burn following consumption of capsaicin in tomato juice. Participants (n = 72, 42 women, 30 men) rated the burn of 30 mL of spicy tomato juice on a general Labeled Magnitude Scale (gLMS) immediately after swallowing, and again every 10 s for 2 min. On 7 of 8 trials, a test beverage (40 mL) was consumed after tomato juice was swallowed, including: skim milk, whole milk, seltzer water, Cherry Kool-Aid, non-alcoholic beer, cola, and water. Participants also answered questions regarding intake frequency and liking of spicy food. Initial burn of tomato juice alone was rated below "strong" but above "moderate" on a gLMS and continued to decay over the 2 min to a mean just above "weak". All beverages significantly reduced the burn of the tomato juice. To quantify efficacy over time, area under the curve (AUC) values were calculated, and the largest reductions in burn were observed for whole milk, skim milk, and Kool-Aid. More work is needed to determine the mechanism(s) by which these beverages reduce burn (i.e., partitioning due to fat, binding by protein, or sucrose analgesia). Present data suggest milk is the best choice to mitigate burn, regardless of fat context, suggesting the presence of protein may be more relevant than lipid content.

Oral sensations and secretions

Sensations experienced in the mouth influence food choices, both immediately and in the long term. Such sensations are themselves influenced by experience with flavors, the chemical environment of the mouth, genetics of receptors for flavors, and individual behavior in the chewing of food. Gustation, the sense of taste, yields information about nutrients, influences palatability, and feeds into the human body's preparation to receive those nutrients. Olfaction, the sense of smell, contributes enormously to defining and identifying food flavors (and is experienced even after placing food inside the mouth). Another vital component of food flavor is texture, which contributes to palatability, especially if a food's texture violates a person's expectations. Next, chemesthesis is the sense of chemically induced irritancy and temperature, for example spiciness and stinging. All of these sensations are potentially modified by saliva, the chemical and physical media of the mouth. As a person experiences the culmination of these oral sensations, modified through an individual's own unique saliva, the flavors in turn influence both what and how a person eats.

Sour Promotes Risk-Taking: An Investigation into the Effect of Taste on Risk-Taking Behaviour in Humans

Taking risks is part of everyday life. Some people actively pursue risky activities (e.g., jumping out of a plane), while others avoid any risk (e.g., people with anxiety disorders). Paradoxically, risk-taking is a primitive behaviour that may lead to a happier life by offering a sense of excitement through self-actualization. Here, we demonstrate for the first time that sour - amongst the five basic tastes (sweet, bitter, sour, salty, and umami) - promotes risk-taking. Based on a series of three experiments, we show that sour has the potential to modulate risk-taking behaviour across two countries (UK and Vietnam), across individual differences in risk-taking personality and styles of thinking (analytic versus intuitive). Modulating risk-taking can improve everyday life for a wide range of people.

Effects of Two Doses of Curry Prepared with Mixed Spices on Postprandial Ghrelin and Subjective Appetite Responses-A Randomized Controlled Crossover Trial

Spices are known to provide orosensory stimulation that can potentially influence palatability, appetite, and energy balance. Previous studies with individual spices have shown divergent effects on appetite and energy intake measures. In a real-life context, however, several spices are consumed in combinations, as in various forms of curries. Therefore, we investigated changes in postprandial appetite and plasma ghrelin in response to the intake of two doses of curry prepared with mixed spices. The study was undertaken in healthy Chinese men, between 21 and 40 years of age and body mass index ≤27.5 kg/m². Appetite was measured using visual analogue scales (VAS) and plasma ghrelin was measured using multiplex assay. Compared with the control meal (Dose 0 Control (D0C), 0 g mixed spices), we found significantly greater suppression in 'hunger' (both p < 0.05, after Bonferroni adjustments) as well in 'desire to eat' (both p < 0.01) during the Dose 1 Curry (D1C, 6 g mixed spices) and Dose 2 Curry (D2C, 12 g mixed spices) intake. There were no differences, however, in plasma ghrelin or in other appetite measures such as in 'fullness' or in 'prospective eating' scores. Overall, the results of our study indicate greater inter-meal satiety due to mixed spices consumption, independent of any changes in plasma ghrelin response.

Application of Intelligent Recommendation Techniques for Consumers' Food Choices in Restaurants

Currently, there has been a new trend in applying modern robotics, information technology, and artificial intelligence to restaurants for improvements of food service, cost-effectiveness, and customer satisfaction. As robots replace humans to serve food, there is a clear need for robotic servers to help consumers select foods from a menu that satisfies their preferences such as taste and nutrition. However, currently, little is known about how eating behaviors drive food choices, and it is often difficult for consumers to make choices from a variety of foods offered by the typical restaurant, even with the assistance from a human server. In this paper, we conduct an exploratory study on an intelligent food choice method that recommends dishes by predicting individual's dietary preference, including ingredients, types of spices, price, etc. A multi-attribute relation matrix tri-factorization (MARMTF) technique is developed for a relation-driven food recommendation system. First, the user's ordering history and their rating scores of the foods in the menu are gathered and represented by a user-dish rating matrix. Next, the attribute relations of the ingredients, spicy level, and price of each food choice are extracted to construct a group of the relation matrices. Then, these matrices are integrated into a large block matrix. In the next step, a matrix tri-factorization algorithm is employed to decompose the block matrix and fuse the complex relationships into matrix factors. Further, a set of approximation block matrices are constructed and the predicted food rating matrix is generated. Finally, the foods (dishes) with sufficiently high preference scores are recommended to the consumers. Our experiments demonstrate that the MARMTF technique can provide effective dish recommendation for customers. Our system significantly simplifies the daunting task of making food choices and has a great potential in providing intelligent and professionally trained non-human waiters and waitresses for employment by future restaurants.