Patterns of sweet liking in sucrose solutions and beverages

Distinct Sensory Hedonic Functions for Sourness in Adults

Over the last half-century, variable responses to sweetness have repeatedly been shown to fall into a small number of hedonic responses, implying that looking only at group means may can obfuscate meaningfully different response patterns. Comparative data for sourness is quite sparse, especially in adults. While increased liking with higher acid concentration has been reported for some children, in adults, sourness is classically assumed to be aversive, with a monotonic drop in liking with increasing sourness. Here, we test this assumption using a simple model system or experimental beverage in convenience samples of adults from the United States (increasing citric acid in water) and Italy (increasing citric acid in pear juice). Participants rated intensity and liking of sampled stimuli. For both cohorts, we find clear evidence of three distinct patterns of responses: a strong negative group where liking dropped with increased sourness, an intermediate group who showed a more muted drop in liking with more sourness, and a strong positive group where liking increased with more sourness. Strikingly, both cohorts showed similar proportions of response patterns, with ~63-70% in the strong negative group, and 11-12% in the strong positive group, suggesting these proportions may be stable across cultures. Notably, the three groups did not differ by age or gender. These data support the existence of different hedonic response profiles to sour stimuli in adults, once again highlighting the importance of looking at individual differences and potential consumer segments, rather than merely averaging hedonic responses across all individuals within a group.

The effect of mango aroma in low-sugar beverage: A sensory study on odor induced sweetness enhancement

Excessive intake of sugar has become a public concern. However, it is challenging for food industries to decrease sugar level without sacrificing safety and sensory profile. Odor-induced sweetness enhancement (OISE) is believed to be a novel and promising strategy for sugar reduction. In order to investigate the OISE effect of mango aroma and evaluate its degree of sugar reduction in low-sugar beverages, a mathematical model was constructed through sensory evaluation in this study. The results showed that the maximum liking of low-sugar model beverages was 4.28 % sucrose and 0.57 % mango flavor. The most synergistic of OISE was at the concentration level of 2.24 % sucrose + 0.25 % mango flavor, which was equivalent to 2.96 % pure sucrose solution. With 32.14 % sugar reduction, the mango aroma was suggested to generate the OISE effect. However, the same level of garlic aroma was not able to enhance sweetness perception, suggesting that the congruency of aroma and taste is a prerequisite for the OISE effect to occur. This study demonstrated that the cross-modal interaction of mango aroma on sweetness enhancement in low-sugar model beverages could provide practical guidance for developing sugar-reduced beverages without applying sweeteners.

Homeostasis Theory of Well-being

The Homeostasis Theory of Well-being proposes a homeostatic modular system for the creation of human well-being. This article aims to: (i) provide a proof-of-concept demonstration of the feasibility of the theory in its biopsychosocial context; (ii) indicate prima facie empirical support for the homeostatic nature of the 16 proposed modules; (iii) discuss the similarities to and differences from other homeostasis theories of well-being. Following the Central Limit Theorem, any homeostatic system with multiple inputs produces outputs with a Gaussian distribution. The data-base of studies contains approximately 2000 publications reporting U- or inverse U-shaped curves for the 16 homeostatic domains specified in the theory. The Homeostasis Theory of Well-being remains speculative and requires controlled longitudinal study to determine the scientific validity of the causal network proposed by the theory. The theory has implications for our understanding of humans' drive for balance, equilibrium and stability in this increasingly uncertain world.

Comparing body composition between the sweet-liking phenotypes: experimental data, systematic review and individual participant data meta-analysis

BACKGROUND

Legislation aimed at reducing sugar intake assumes that sweet-liking drives overconsumption. However, evidence that a greater liking for sweet taste is associated with unhealthier body size is mixed and complicated by relatively small samples, an overreliance on body mass index (BMI) and lack of classification using sweet-liking phenotypes.

METHODS

We first examined body size data in two larger samples with sweet-liking phenotyping: extreme sweet-likers, moderate sweet-likers and sweet-dislikers. Adults (18-34yrs), attended a two-session lab-based experiment involving phenotyping for sweet-liking status and a bioelectrical impedance body composition measurement (Experiment One: N = 200; Experiment Two: N = 314). Secondly, we conducted an individual participant data (IPD) meta-analysis: systematic searches across four databases identified 5736 potential articles. Of these, 53 papers met our search criteria: a taste assessment that measured liking using sucrose (>13.7% w/v), which allowed sweet-liking phenotyping and included either BMI, body fat percentage (BF%), fat-free mass (FFM) or waist-circumference.

RESULTS

A significant effect of sweet-liking phenotype on FFM was found in both Experiment One and Two, with extreme sweet-likers having significantly higher FFM than sweet-dislikers. In Experiment One, sweet-dislikers had a significantly higher BF% than extreme sweet-likers and moderate sweet-likers. However, as these data are from one research group in a young, predominantly westernised population, and the results did not perfectly replicate, we conducted the IPD meta-analyses to further clarify the findings. Robust one-stage IPD meta-analyses of 15 studies controlling for sex revealed no significant differences in BF% (n = 1836) or waist-circumference (n = 706). For BMI (n = 2368), moderate sweet-likers had slightly lower BMI than extreme sweet-likers, who had the highest overall BMI. Most interestingly, for FFM (n = 768), moderate sweet-likers and sweet-dislikers showed significantly lower FFM than extreme sweet-likers.

CONCLUSION

The higher BMI often seen in sweet-likers may be due to a larger FFM and questions the simple model where sweet liking alone is a risk factor for obesity.

Sweet liking predicts liking and familiarity of some alcoholic beverages, but not alcohol intake: A population study using a split-sample approach

Sweetness has been proposed to be an important quality in the decision to consume alcohol, and strong preferences for sweet tastes have been associated with alcohol abuse. However, alcohol is characterized by a number of other sensory properties, including astringency and bitterness that may drive preference and consumption. Spinelli et al. (2021) classified individuals into three sweet-sensory liking clusters (High Sweet-Liking, Moderate Sweet-Liking, and Inverted-U) that differed in their sweetness optima and sensory-liking patterns (relationship between liking and sweetness, bitterness and astringency perception in a food model). The current paper replicates the sweet sensory-liking clusters in a new set of participants (n = 1976), and extends the predicted value of these clusters examining their relationship to wine and other types of alcoholic beverages by gender using a split-sample approach on a total of over 3000 adults. The sweet sensory-liking clusters had a predictive relationship for the familiarity and liking of some alcoholic beverages characterized by stronger tastes, but not weekly alcohol intake levels. Thus, although sweet sensory-liking clusters may be associated with the type of beverages and frequency with which a person will drink and enjoy a type of alcoholic beverage, they are poor predictors of the quantity of alcohol that a person ingests over the course of a week.

Reducing sweetness expectation in milk tea by crossmodal visuo-auditory interaction

In the realm of healthy dietary choices about reducing sweetness perception, the exploration of crossmodal effects stands as a frequently employed approach. Both music and color can independently influence flavor evaluation and gustatory experience by eliciting emotions. However, less research has been done on the effects of audio-visual crossmodal interactions on sweetness expectations and perceptions. The present study conducted two experiments delving into the crossmodal effect on sweetness expectation and perception of milk tea by manipulating the emotional valence of music and packaging color. The results showed that positive (vs. negative) music led to higher sweetness expectations and perceptions for milk teas with neutral packaging color. Irrespective of music, participants had higher sweetness expectations for milk tea with positive or neutral (vs. negative) packaging colors. The congruence of valence between music and packaging color influenced sweetness perception. Positive (vs. negative) music correlated with a sweeter perception when the packaging color was positive. Exposed to negative music, subjects showed a higher sweetness perception with negative (vs. positive) packaging colors. In conclusion, the results suggest that the valence of music and packaging color crossmodally influence consumers' evaluation of milk tea, and it differs depending on whether it was tasted. Thus, this study has demonstrated the crossmodal influence of music and packaging color, providing valuable implications for healthy eating and marketing applications.

Children's reaction to sugar reduced dairy desserts in the context of the implementation of nutritional warning labels: An exploratory study

The aim of the present work was to explore children's reaction to sugar reduction in the context of the implementation of nutritional warnings in Uruguay. The study was composed of two sessions involving three evaluation conditions: tasting without package information, package evaluation without tasting, and tasting with package information. A total of 122 children, ages ranging between 6 and 13 years old (47% girls) were involved in the study. In the first session, children's hedonic and emotional response to a regular and a sugar-reduced chocolate dairy dessert (without other sweeteners) was evaluated. In the second session, children first evaluated their expected liking, emotional associations and choice of packages differing in the presence of warning labels for excessive sugar content and cartoon character (2x2 design). Finally, they tasted the selected sample in the presence of the package and evaluated their liking, emotional associations, and intention to re-taste it. Although sugar reduction led to a significant reduction in overall liking, the dessert with 40% sugar reduction showed a mean overall score of 6.5 in a 9-point hedonic scale and was described using positive emoji (, , ). When the desserts were tasted with package information, no significant differences in the expected overall liking of the regular and sugar-reduced dessert were found. Regarding the effect of packaging elements, the presence of a warning label highlighting excessive content of sugar did not have a significant effect on children's choice. Instead, children's choices were defined by the presence of a cartoon character. Results from the present work provide additional evidence about the feasibility of reducing the sugar content and sweetness of dairy products targeted at children and stress the need to regulate the use of cartoon characters on products with an unfavorable nutritional profile. Methodological recommendations for sensory and consumer research with children are also discussed.

The Effects of Acute Sleep Curtailment on Salt Taste Measures and Relationships with Energy-Corrected Sodium Intake: A Randomized Cross-Over Trial with Methodology Validation

(1) Background: Sleep may be a factor that influences the taste-dietary intake relationship. The effect of sleep on salt taste measures has not been adequately studied, and no standardized methodology has been developed for measuring salt taste preference. (2) Methods: A sweet taste forced-choice paired-comparison test was adapted and validated to determine salt taste preference. In a randomized cross-over trial, participants slept a curtailed night (33% reduction in sleep duration) and a habitual night, confirmed by a single-channel electroencephalograph. Salt taste tests were conducted the day after each sleep condition using five aqueous NaCl solutions. One 24-h dietary recall was obtained after each taste test. (3) Results: The adapted forced-choice paired-comparison tracking test reliably determined salt taste preference. No changes in salt taste function (intensity slopes: p = 0.844) or hedonic measures (liking slopes: p = 0.074; preferred NaCl concentrations: p = 0.092) were observed after the curtailed sleep condition compared to habitual sleep. However, sleep curtailment disrupted the association between liking slope and energy-corrected Na intake (p < 0.001). (4) Conclusions: The present study serves as the first step toward more standardized taste assessments to facilitate comparison between studies and suggests accounting for sleep when exploring taste-diet relationships.

Crossmodal correspondences between basic tastes and visual design features: A narrative historical review

People tend to associate abstract visual features with basic taste qualities. This narrative historical review critically evaluates the literature on these associations, often referred to as crossmodal correspondences, between basic tastes and visual design features such as color hue and shape curvilinearity. The patterns, discrepancies, and evolution in the development of the research are highlighted while the mappings that have been reported to date are summarized. The review also reflects on issues of cross-cultural validity and deviations in the matching patterns that are observed when correspondences are assessed with actual tastants versus with verbal stimuli. The various theories that have been proposed to account for different classes of crossmodal correspondence are discussed, among which the statistical and affective (or emotional-mediation) accounts currently appear most promising. Several critical research questions for the future are presented to address the gaps that have been identified in the literature and help validate the popular theories on the origin and operations of visual-taste correspondences.

Characterizing Individual Differences in Sweet Taste Hedonics: Test Methods, Locations, and Stimuli

Sweetness drives the consumption of added sugars, so understanding how to best measure sweet hedonics is important for developing strategies to lower sugar intake. However, methods to assess hedonic response to sweetness vary, making results across studies difficult to integrate. We compared methods to measure optimal sucrose concentration in 21 healthy adults (1) using paired-comparison preference tracking vs. ratings of liking, (2) with participants in the laboratory vs. at home, and (3) using aqueous solutions vs. vanilla milk. Tests were replicated on separate days to assess test-retest reliability. Test-retest reliability was similar between laboratory and home testing, but tended to be better for vanilla milk and preference tracking. Optimal sucrose concentration was virtually identical between laboratory and home, slightly lower when estimated via preference tracking, and about 50% lower in vanilla milk. However, optimal sucrose concentration correlated strongly between methods, locations, and stimuli. More than 50% of the variability in optimal sucrose concentration could be attributed to consistent differences among individuals, while much less variability was attributable to differences between methods. These results demonstrate convergent validity between methods, support testing at home, and suggest that aqueous solutions can be useful proxies for some commonly consumed beverages for measuring individual differences.

Re-evaluating how sweet-liking and PROP-tasting are related

Past research has identified distinct phenotypic differences in responses to sweet taste, although the origins of these differences remain unclear. One possibility is that these individual differences in sweet-liking are a manifestation of the more widely known differences in sensitivity to the bitter tastant 6-n-propylthiouracil (PROP), which has been related to wider differences in food liking and preference. However, previous studies exploring the relationship between sweet-liking and PROP-tasting have had mixed outcomes. This is possibly due to older studies using a more simplistic dichotic characterisation of sweet likers, whereas recent research suggests three sweet-liking phenotypes (extreme sweet likers, ESL; moderate sweet likers, MSL; and sweet dislikers, SD). To re-assess how sweet-liking and PROP tasting are inter-related, 236 volunteers evaluated their liking for 1.0 M sucrose and the intensity of three concentrations of each NaCl and PROP. Using three different methods for classifying PROP taster status, our analysis confirmed that all three sweet-liking phenotypes were represented in all three PROP taster groups (super-tasters, ST; medium tasters, MT; and non-tasters, NT), but relatively few ESL were classified as ST, or SD as NT. Overall, these data suggest that while PROP tasting and sweet-liking are not causally related, the SD phenotype may partly be explained by a broader tendency for anhedonia.

Relationships between Intensity and Liking for Chemosensory Stimuli in Food Models: A Large-Scale Consumer Segmentation

This study, which was conducted as part of the Italian Taste project, was aimed at exploring the relationship between actual liking and sensory perception in four food models. Each food model was spiked with four levels of prototypical tastant (i.e., citric acid, sucrose, sodium chloride, capsaicin) to elicit a target sensation (TS) at an increasing perceived intensity. Participants (N = 2258; 59% women, aged 18-60) provided demographic information, a stated liking for 40 different foods/beverages, and their responsiveness to tastants in water. A food-specific Pearson's coefficient was calculated individually to estimate the relationship between actual liking and TS responsiveness. Considering the relationship magnitude, consumers were grouped into four food-specific clusters, depending on whether they showed a strong negative (SNC), a weak negative (WNC), a weak positive (WPC), or a strong positive correlation (SPC). Overall, the degree of liking raised in parallel with sweetness responsiveness, fell as sourness and pungency perception increased, and showed an inverted U-shape relationship with saltiness. The SNC clusters generally perceived TSs at higher intensities, except for sourness. Clusters were validated by associating the level of stated liking towards food/beverages; however, some unexpected indications emerged: adding sugar to coffee or preferring spicy foods differentiated those presenting positive correlations from those showing negative correlations. Our findings constitute a step towards a more comprehensive understanding of food preferences.

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.

Visual cues associated with sweet taste increase short-term eating and grab attention in healthy volunteers

Most studies that examine responses to food cues use images of actual foods as stimuli. Since foods are rewarding in multiple ways, it then becomes difficult to try and partial out the role of the importance of different aspects of food reward. Here we aimed to evaluate the impact of novel visual cues specifically associated with the immediate sensory reward from a liked sweet taste. In the training phase, one visual cue (CSsweet) was associated with the experience of sweet taste (10%sucrose) and a second, control cue (CSneutral) with a neutral taste (artificial saliva) using a disguised training procedure. In Experiment 1, participants (n = 45) were given an ad libitum snack intake test 30 min post-training, either labelled with CSsweet or CSneutral. Total caloric consumption was significantly higher in the CSsweet (650 ± 47 kcal) than CSneutral (477 ± 45 kcal) condition, but ratings of liking for the snacks did not differ significantly between conditions. In Experiment 2, participants (n = 80) exhibited an overall attentional bias (22.1 ± 9.9 ms) for the CSsweet relative to CSneutral cue (assessed using a dot-probe task), however rated liking for the CSsweet did not change significantly after cue-sweet training. Likewise, measures of expected satiety for drinks labelled with CSsweet did not differ significantly from CSneutral. Overall these two experiments provide evidence that associations between neutral visual cues and the experience of a liked sweet taste leads to cue-potentiated eating in the presence of the CSsweet cue. With no evidence that cue-sweet training altered rated liking for the visual cues, and in keeping with extant literature on the dissociation of hedonic and rewarding properties of food rewards, we propose this potentiation effect to reflect increased incentive salience.

Food Preferences and Obesity

Obesity is a multifactorial disease with several potential causes that remain incompletely understood. Recent changes in the environment, which has become increasingly obesogenic, have been found to interact with individual factors. Evidence of the role of taste responsiveness and food preference in obesity has been reported, pointing to a lower taste sensitivity and a higher preference and intake of fat and, to a lesser extent, sweet foods in obese people. Studies in the last decades have also suggested that individual differences in the neurophysiology of food reward may lead to overeating, contributing to obesity. However, further studies are needed to confirm these findings. In fact, only a limited number of studies has been conducted on large samples, and several studies were conducted only on women. Larger balanced studies in terms of sex/gender and age are required in order to control the confounding effect of these variables. As many factors are intertwined in obesity, a multidisciplinary approach is needed. This will allow a better understanding of taste alteration and food behaviours in obese people in order to design more effective strategies to promote healthier eating and to prevent obesity and the related chronic disease risks.

Understanding sweet-liking phenotypes and their implications for obesity: Narrative review and future directions

Building on a series of recent studies that challenge the universality of sweet liking, here we review the evidence for multiple sweet-liking phenotypes which strongly suggest, humans fall into three hedonic response patterns: extreme sweet likers (ESL), where liking increases with sweetness, moderate sweet likers (MSL), who like moderate but not intense sweetness, and sweet dislikers (SD), who show increasing aversion as sweetness increases. This review contrasts how these phenotypes differ in body size and composition, dietary intake and behavioural measures to test the widely held view that sweet liking may be a key driver of obesity. Apart from increased consumption of sugar-sweetened beverages in ESL, we found no clear evidence that sweet liking was associated with obesity and actually found some evidence that SD, rather than ESL, may have slightly higher body fat. We conclude that ESL may have heightened awareness of internal appetite cues that could protect against overconsumption and increased sensitivity to wider reward. We note many gaps in knowledge and the need for future studies to contrast these phenotypes in terms of genetics, neural processing of reward and broader measures of behaviour. There is also the need for more extensive longitudinal studies to determine the extent to which these phenotypes are modified by exposure to sweet stimuli in the context of the obesogenic environment.

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.

Consumer acceptance of watermelon flesh-rind blends and the effect of rind on refreshing perception

Watermelon flesh is widely consumed for its appealing flavor and refreshing properties, though the rind of the fruit also has traits of interest, especially its nutritional benefits. This study aimed to determine if watermelon flesh blended with 0%, 10%, 20%, and 30% w/w rind could appeal to consumers, and the effect of rind on the refreshing perception was investigated. Consumers (n = 102) evaluated the liking and intensity levels of overall flavor, sweet, sour, green, watermelon flavor, and refreshing quality along with questions regarding the texture, off flavors, and aftertaste of the samples. The addition of rind was acceptable up to the 20% rind level, which was given an overall rating above the midpoint of the scale, while the 10% and 0% rind samples did not differ significantly (P < 0.001). Overall liking most strongly correlated with sweet liking (r = 0.78, P < 0.001) and watermelon flavor liking (r = 0.77, P < 0.001). Refreshing liking most strongly correlated with watermelon flavor liking (r = 0.75, P < 0.001) and decreased with addition of rind in the samples (P < 0.001). The excessive green notes, off flavors, and undesirable texture of rind decreased the hedonic and refreshing ratings of samples with 20% and 30% rind, respectively. This research demonstrated the acceptability of using up to 20% rind to supplement watermelon juice blends and results suggested that watermelon flavor drives the refreshing perception. PRACTICAL APPLICATION: These findings exhibit the diversity in consumer preferences for watermelon flesh blended with rind using a consumer test. The refreshing properties of watermelon flesh as related to sweetness and watermelon flavor, along with the flavor and mouthfeel attributes contributed by watermelon rind, are highlighted. Manufacturers of fruit-based beverages can apply this research to inform development of refreshing products, watermelon flavored products, or products that utilize rind waste.

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.

Texture Preferences of Chinese, Korean and US Consumers: A Case Study with Apple and Pear Dried Fruits

The present study aimed to understand the drivers of liking dried apple and pear chips with various textures among Chinese (n = 58), Korean (n = 58), and US (n = 56) consumers. The possibility of hedonic transfer from snack texture preferences to fruit-chip texture preferences was also investigated among Chinese and Koreans. Fourteen fruit-chip samples with four textural properties (crispy, puffy, soft, and jelly-like) were selected. Consumers rated their level of liking for each sample, and then they performed hedonic-based projective mapping with the same samples. In the hedonic texture transfer investigation, consumers rated their acceptance of nine snacks with various textures but possessing similar textures to those of dried fruit samples. The data were analyzed by ANOVA and multiple factor analysis. Most consumers disliked samples with a soft or jelly-like texture, while liked samples with a crispy texture. Cross-cultural differences were observed in the liking of puffy samples, with both Chinese and Koreans liking puffy samples as much as crispy ones for their melting characteristics in the mouth, while US consumers perceived the puffy samples as being Styrofoam-like and disliked them. Hedonic transfer was observed from snack texture preferences to fruit-chip. Individual texture preferences for snacks seem to significantly affect the texture preferences for fruit chips.

Individual Differences in Sweetness Ratings and Cross-Modal Aroma-Taste Interactions

Aroma-taste interactions, which are believed to occur due to previous coexposure (concurrent presence of aroma and taste), have been suggested as a strategy to aid sugar reduction in food and beverages. However, coexposures might be influenced by individual differences. We therefore hypothesized that aroma-taste interactions vary across individuals. The present study investigated how individual differences (gender, age, and sweet liker status) influenced the effect of aroma on sweetness intensity among young adults. An initial screening of five aromas, all congruent with sweet taste, for their sweetness enhancing effect was carried out using descriptive analysis. Among the aromas tested, vanilla was found most promising for its sweet enhancing effects and was therefore tested across three sucrose concentrations by 129 young adults. Among the subjects tested, females were found to be more susceptible to the sweetness enhancing effect of vanilla aroma than males. For males, the addition of vanilla aroma increased the sweet taste ratings significantly for the 22–25-year-olds, but not the 19–21-year-olds. Consumers were clustered according to their sweet liker status based on their liking for the samples. Although sweet taste ratings were found to vary with the sweet liker status, aroma enhanced the sweetness ratings similarly across clusters. These results call for more targeted product development in order to aid sugar reduction.

The Effect of Sleep Curtailment on Hedonic Responses to Liquid and Solid Food

It is currently unclear whether changes in sweet taste perception of model systems after sleep curtailment extend to complex food matrices. Therefore, the primary objective of this study was to use a novel solid oat-based food (crisps) and oat-based beverage stimulus sweetened with sucralose to assess changes in taste perception after sleep curtailment. Forty-one participants recorded a habitual and curtailed night of sleep using a single-channel electroencephalograph. The next morning, overall sweetness, flavor, and texture liking responses to energy- and nutrient-matched oat products across five concentrations of sweetness were measured. Overall (p = 0.047) and flavor (p = 0.017) liking slopes across measured concentrations were steeper after curtailment, suggesting that sweeter versions of the oat products were liked more after sleep curtailment. Additionally, a hierarchical cluster analysis was used to classify sweet likers and non-likers. While the effect of sleep curtailment on sweet liking did not differ between sweet liking classification categories, sleep curtailment resulted in decreased texture liking in the solid oat crisps for sweet non-likers (p < 0.001), but not in the oat beverage. These findings illustrate the varied effects of sleep on hedonic response in complex food matrices and possible mechanisms by which insufficient sleep can lead to sensory-moderated increases in energy intake.

Multiple Dimensions of Sweet Taste Perception Altered after Sleep Curtailment

Short sleep duration increases preferences for high-carbohydrate and high-fat foods. It is unclear if insufficient sleep-induced changes in food preference are mediated by changes in taste perception and if these changes are related to sweetener type (sucrose or sucralose) or sweet liking phenotype. The primary objective of this study was to determine if sleep curtailment results in changes in sweet taste perception after sleep curtailment. Forty participants used a single-channel electroencephalograph to record both a habitual and curtailed night (33% reduction) of sleep at home. The following morning, multiple dimensions of sweet taste perception were measured, including preferred sweetener concentrations, patterns of sweet liking, and intensity perception over a range of concentrations. After curtailment, a significant increase in preferred concentration for both sucrose and sucralose (p < 0.001 for both) was observed. The slope of sucrose sweet liking increased after curtailment (p = 0.001). The slope of sucralose liking also increased, but this was not significant (p = 0.129). Intensity perception of the sweeteners was not altered by curtailment. Hierarchical cluster analysis was used to classify participants by sweet liking phenotype. Phenotypes were found to predict preferred sweetener concentration. These findings illustrate a possible need to control for sleep in food sensory studies and suggest a potential mechanism by which insufficient sleep can lead to excess energy intake.

Quantifying Sweet Taste Liker Phenotypes: Time for Some Consistency in the Classification Criteria

Taste hedonics is a well-documented driver of food consumption. The role of sweetness in directing ingestive behavior is largely rooted in biology. One can then intuit that individual differences in sweet-liking may constitute an indicator of variations in the susceptibility to diet-related health outcomes. Despite half a century of research on sweet-liking, the best method to identify the distinct responses to sweet taste is still debated. To help resolve this issue, liking and intensity ratings for eight sucrose solutions ranging from 0 to 1 M were collected from 148 young adults (29% men). Hierarchical cluster analysis (HCA) revealed three response patterns: a sweet-liker (SL) phenotype characterized by a rise in liking as concentration increased, an inverted U-shaped phenotype with maximum liking at 0.25 M, and a sweet-disliker (SD) phenotype characterized by a decline in liking as a function of concentration. Based on sensitivity and specificity analyses, present data suggest the clearest discrimination between phenotypes is seen with 1.0 M sucrose, where a liking rating between -15 and +15 on a -50/+50 scale reliably distinguished individuals with an inverted U-shaped response from the SLs and the SDs. If the efficacy of this approach is confirmed in other populations, the discrimination criteria identified here can serve as the basis for a standard method for classifying sweet taste liker phenotypes in adults.

Functional Properties of a High Protein Beverage Stabilized with Oat-β-Glucan

This study evaluated the effect of oat flour and milk protein on the functional properties and sensory acceptability of shelf stable high protein dairy beverages containing at least 0.75 g of oat-β-glucan per serving size. Formulations adjusted to levels of 1.50% to 2.30% oat flour and 2.50% to 4.00% milk protein isolate (MPI) were thermal processed in a rotary retort. The finished product exhibited good suspension stability (>80%). The increase of oat and MPI contents lead to nectar-like beverages (51 to 100 mPas). However, oat flour was the component showing the highest effect on the viscosity coefficient values of the beverages. Sensory evaluation indicated that formulations with less than 1.9% oat flour and 2.5% MPI (thin liquid, <50 mPas) were the most accepted. Mouthfeel (perceived thickness), sweetness and aftertaste had the most influence on overall liking of the beverages.

PRACTICAL APPLICATION

Overall, this study comprises the development of a functional food product. Supplementation of beverages with fiber from oats is an innovative approach to stabilize high protein beverages. Ready to drink protein beverage formulations use gums to stabilize the product and provide a desirable mouthfeel. The levels of oat-β-glucan used in the beverage increased the thickness and meet the requirement of the FDA approved health claim for reduction of the cardiovascular disease risk (21 CFR 101.81).

Sweet liker status in children and adults: Consequences for beverage intake in adults

Different patterns of sweet liking exist. For some, liking increases as concentration increases up to a point at which it typically plateaus. These individuals are referred to as sweet likers. How sweet likers' beverage intake, especially sugar sweetened beverage intake, differs from sweet dislikers' beverage intake is not well characterized. A total of 953 visitors (650 adults; 62.0% women; 303 children; 58.7% girls) to the Denver Museum of Nature & Science rated the taste intensity and liking of 5 sucrose solutions that spanned concentrations typically encountered in sugar-sweetened beverages (0.0-13.7% w/v) using visual analog scales. Beverage intake by adults was quantified using the validated BEVQ-15 questionnaire. Among adults, hierarchical cluster analysis identified three clusters of liking patterns (likers, dislikers, and neutrals). Among children, two clusters of liking patterns were identified (likers and dislikers). For both adults and children, BMI, percent body fat, age, and sex did not differ between clusters. Concentration by cluster interaction effects were observed for both adults and children. Adult sweet likers consumed more energy from all beverages, more sweetened juice and tea, and less water than those in other clusters. Sweet liker status may be a useful predictor of increased energy intake from beverages, but prospective trials are necessary to confirm this utility.

Patterns of Sweet Taste Liking: A Pilot Study

Two distinct patterns of sweet taste liking have been described: one showing a peak liking response in the mid-range of sucrose concentrations and the other showing a monotonic liking response at progressively higher sucrose concentrations. Classification of these patterns has been somewhat arbitrary. In this report, we analyzed patterns of sweet taste liking in a pilot study with 26 adults including 14 women and 12 men, 32.6 ± 14.5 years of age with body mass index 26.4 ± 5.1 kg/m² (mean ± SD). Sweet taste liking was measured for 10 levels of sucrose solutions (0.035 M to 1.346 M). Participants rated their liking of each solution using a visual analog scale with 0 indicating strongly disliking and 100 strongly liking. The cluster analysis demonstrated two distinct groups: 13 liked relatively low sucrose concentrations and liked high sucrose concentrations less, and 13 liked high sucrose concentrations greatly. If we use the 0.598 M sucrose solution alone and a cutoff liking score of 50, we can distinguish the two clusters with high sensitivity (100%) and specificity (100%). If validated in additional studies, this simple tool may help us to better understand eating behaviors and the impact of sweet taste liking on nutrition-related disorders.