General Labeled Magnitude Scale Research Articles

The gustin gene variation at rs2274333 and PROP taster status affect dietary fat perception: a stepwise multiple regression model study

Gustin, a trophic factor for taste bud development, and its polymorphism at rs2274333 influence taste perception of 6-n-propylthiouracil (PROP) and fungiform papillae (FP) density. The PROP taster status affects dietary fat sensing and body composition. However, there is a paucity of research on the gustin genotype with dietary fat perception, PROP tasting ability, and body mass index (BMI). Thus, taste sensitivity to fat and bitterness was evaluated in 178 healthy individuals. The general labeled magnitude scale was used to determine suprathreshold taste intensity ratings, whereas the alternative forced choice approach was used to estimate the taste-sensing ability. The FP density was assessed by applying blue-colored food dye over the anterior region of the tongue. Restriction fragment length polymorphism was used to detect the genetic polymorphism (rs2274333) in the carbonic anhydrase VI (CA-VI) gene. Fisher's chi-square analysis showed that the CA-VI genotype and allelic frequencies significantly correlated (p<0.001) with the PROP taster status and BMI. Healthy individuals with AA genotypes of the CA-VI polymorphism and PROP super-tasters demonstrated stronger gustatory sensitivity for linoleic acid (LA) with greater FP density in comparison to individuals with AG/GG genotypes and other PROP taster groups. Stepwise forward multiple regression analysis indicates that BMI and PROP taster status significantly influence the LA sensing ability. The suprathreshold intensity rating for LA was also significantly impacted by PROP taster status and CA-VI genotypes, with a variation of 73.3%. Overall, our findings show a relationship between the taste papillae environment and the CA-VI genetic mutation at rs2274333, which influenced the gustatory preference for dietary fat and bitter taste.

Inducible desensitization to capsaicin with repeated low-dose exposure in human volunteers

Responses to capsaicin are reduced following repeated exposure, a phenomenon known as capsaicin desensitization. Heavy consumers of chilies consistently report reduced oral burn relative to infrequent consumers, presumably due to chronic desensitization. However, the mechanism(s) underlying capsaicin desensitization remain poorly understood. We hypothesized that reduced response to capsaicin due to repeated oral exposure may result from a change in the expression of the capsaicin receptor (TRPV1) gene. To test this, we conducted two longitudinal desensitization studies in healthy human volunteers. In Study 1, 51 adults completed a 17-day capsaicin desensitization protocol. The study consisted of three in-person visits where they were asked to sample stimuli, including 3, 6, and 9 ppm capsaicin, and rate intensity on a general labeled magnitude scale (gLMS). Between days 3 & 17, participants rinsed at home with 6 ppm capsaicin (n = 31) or a control (n = 20) solution (20 uM sucrose octaccetate; SOA) twice a day. Before and after the oral exposure protocol, a clinician collected fungiform papillae. Participants randomized to the capsaicin rinse showed a statistically significant reduction in oral burn ratings that was not observed in controls, indicating repeated low-dose exposure can systematically induce desensitization. TRPV1 expression was not associated with reported capsaicin burn, and there was no evidence of a decrease in TRPV1 expression following capsaicin exposure. In Study 2, participants (n = 45) rinsed with 6 ppm capsaicin in a similar protocol, rating capsaicin, vanillyl butyl ether (VBE), cinnamaldehyde, ethanol, menthol, and sucrose on days 1, 3, & 17. Burn from capsaicin, VBE, cinnamaldehyde, and ethanol all showed a statistically significant change – capsaicin, VBE and cinnamaldehyde burn all dropped ∼20 %, and a larger reduction was seen for ethanol – while menthol cooling and sucrose sweetness did not change. Collectively, this suggests reductions in oral burn following chronic capsaicin exposure generalizes to other stimuli (i.e., cross desensitization) and this cannot be explained by a change in TRPV1 mRNA expression. More work is needed to elucidate the underlying mechanism for capsaicin desensitization in the oral cavity.

More than fat – Proteins in dairy and plant milks contribute to the reduction of oral burn from capsaicin

The effectiveness of cow’s milk in reducing capsaicin-induced burn is well-known, and typically attributed to capsaicin’s lipophilicity. Still, controlled laboratory studies show full-fat milk is not more efficacious than fat-free milk, suggesting other components may contribute to milk’s effectiveness. Recent research has shown milk proteins like micellar casein and whey reduce capsaicin burn in the absence of fat. This paper reports two experiments in moderate capsaicin users that investigate the efficacy of dairy and plant milks varying in fat and protein content. In Experiment One, participants were exposed to 5-ppm capsaicin solutions before rinsing with conventional full-fat milk, ultra-filtered full-fat milk, almond milk, soy milk, and pea protein-enriched flax milk. In Experiment Two, they rinsed with fat-free, conventional full-fat, and ultra-filtered full-fat milk, and three soy milks of varying protein content. Participants made burn ratings on a general Labelled Magnitude Scale (gLMS) once every 10 s for 2-min (Experiment One) or continuously for 2-min (Experiment Two). Experiment One showed significant main effects of time and sample, with planned comparisons revealing differences for water versus conventional and ultra-filtered full-fat milk. In Experiment Two, a main effect of time and a time-by-sample interaction were observed, with samples in both blocks (soy milk, dairy milk) significantly outperforming water. Some evidence of a concentration-dependent effect was observed for protein, with both experiments suggesting ultra-filtered high protein full-fat milk was most efficacious. These findings suggest proteins play a role in mitigating capsaicin burn, although further research is needed to quantify the relative contributions of fat and protein.

Effect of white pepper addition on the sensory perception of sodium‐reduced soup with an emphasis on saltiness perception

AbstractChemical irritants, like piperine in pepper, have been identified to have cross‐modal interactions, including increasing the perception of saltiness. Processed foods have used cross‐modal interactions (e.g., odor and taste) to improve acceptability of salt‐reduced foods. Cross‐modal interactions between piperine and taste could be applied to increase consumer perception of saltiness in low‐sodium food products. As such the objective of this study was to determine how the addition of white pepper to low‐sodium soup affects its' sensory perception. First, the aroma detection threshold (n = 60) of white pepper was determined. Then white pepper (at detection threshold) was added to a low‐sodium soup and evaluated using hedonic scales, general labeled magnitude scale for saltiness, check‐all‐that‐apply (CATA), and temporal check‐all‐that‐apply (TCATA; n = 76). The results indicated that the saltiness intensity increased with the addition of white pepper based on the results of the general labeled magnitude scale; however, this result was not confirmed using CATA or TCATA. Rather peppery, bitterness, sourness, and strong aftertaste attributes dominated the participants' perception of the soup. The addition of white pepper also decreased the participants' overall liking of the soup as well as their liking of the flavor and texture. Future research should continue to investigate the cross‐modal interactions of white pepper.Practical ApplicationThe food industry is acting in response to consumer concerns by reducing the salt content in their foods. Despite being a positive initiative for human health, a reduction in the salt content of foods can yield a reduction in sensory appeal and flavor intensity. This study investigated the use of white pepper to increase the saltiness perception of low‐sodium soup. The results indicated that white pepper added bitterness and strong aftertaste to the soup while simultaneously suppressing other flavors. This study also found that white pepper decreased the acceptability of the soup and indicated that white pepper may not be an ingredient that can mitigate the reduction in salt in food products.

College-Aged Males Experience Attenuated Sweet and Salty Taste with Modest Weight Gain

BackgroundHuman and animal studies report a blunted sense of taste in people who are overweight or obese, with heightened sensitivity also reported after weight loss. However, it is unknown if taste changes concurrently with weight gain. ObjectiveThis study investigated the association of weight gain with changes in suprathreshold taste intensity perception in a free-living population of young adults. MethodsTaste response, anthropometric measures, and diet changes were assessed with a longitudinal study design in first-year college students 3 times throughout the academic year. At baseline, 93 participants (30 males, 63 females) were an average of 18 y old, with a body mass index (in kg/m2) of 21.9. Sweet, umami, salty, sour, and bitter taste intensities were evaluated at 3 concentrations by using the general Labeled Magnitude Scale. Ordinary least-squares regression models assessed the association of weight gain and within-person taste change, adjusting for sex, race, and diet changes. ResultsParticipants gained an average of 3.9% in weight, ranging from −5.7% to +13.8%. With each 1% increase in body weight, males perceived sweet and salty as less intense, with taste responses decreasing by 11.0% (95% CI: −18.9%, −2.3%; P = 0.015) and 7.5% (95% CI: −13.1%, −1.5%; P = 0.015) from baseline, respectively. Meanwhile, females did not experience this decrement, and even perceived a 6.5% increase (95% CI: 2.6%, 10.5%; P = 0.007) in sour taste with similar amounts of weight gain. Changes in the consumption of meat and other umami-rich foods also negatively correlated with umami taste response (−39.1%; 95% CI: −56.3%, −15.0%; P = 0.004). ConclusionA modest weight gain is associated with concurrent taste changes in the first year of college, especially in males who experience a decrement in sweet and salty taste. This suggests that young-adult males may be susceptible to taste loss when gaining weight.

Tongue papillae density and fat taster status- a cardinal role on sweet and bitter taste perception among Indian population

Obesity is a complex nutritional disorder that may be influenced by calorie intake and eating behaviours. Aside from many studies, the influence of papillae count on obesity is still debated. Despite the multiple variables connected to weight gain and altered taste perception, determining the association between papillae count and taste sensitivity to fat, sweet and bitter tastes, in particular, has recently become a focus of attention. This study aimed to rule out the relationship between the number of papillae on different areas of the tongue and taste sensitivity in people (n = 150) among the various groups depending on their body mass index (BMI) and fat taste sensitivity. The general labelled magnitude scale (gLMS) was used for the taste sensitivity analysis, and participants were asked to rate the intensity of each concentration of the different tastants. Using a digital camera to obtain a picture of the tongue, the density of the papillae on the tongue was counted manually by three different operators. The study reveals that the total papillae density and BMI had a direct negative correlation (r = -0.43), with papillae density (PD) decreasing as BMI increased. Concurrently, persons with higher BMIs had lower papillae distributions (32.38 ± 1.85 PD/cm2) and significantly lower perceptions of the intensity of fat taste. Further examining papillae density in the anterior front part of the tongue, the front-right section, showed significantly higher papillae distribution (74.04 ± 2.11 PD/cm2) than the front-left section. When considering the sensitivity in the tip of the tongue, middle tongue, and whole mouth, high-sensitivity individuals for fat are more sensitive to both sweet and bitter tastes. Overall, the results of this study demonstrated a strong relationship between taste sensitivity in the Indian population, BMI, and tongue papillae density in various regions of the tongue.

Variation in TAS2R receptor genes explains differential bitterness of two common antibiotics.

For pharmaceuticals to deliver their full benefits with maximum efficacy, patients need to follow recommended dosing schedules, in terms of amount and frequency. Unfortunately, the aversive taste of many drugs, especially bitterness, can reduce patient compliance in oral liquid formulations. Given common genetic differences in bitter taste receptor genes (TAS2Rs), some individuals may be at increased risk for poor compliance due to heightened bitterness that becomes a barrier to proper use. Here we report on the sensory profile of two antibiotics, chloramphenicol and ofloxacin, investigating whether bitterness intensity associates with nominally functional TAS2R variants. Participants (n = 143) rated suprathreshold intensity on a general Labeled Magnitude Scale (gLMS) for chloramphenicol and ofloxacin; propylthiouracil (PROP) was included as a control, given robust prior associations with TAS2R38 variants. The dominant sensation from chloramphenicol and ofloxacin was bitterness, falling just below “moderate” on a gLMS. TAS2R38 diplotype associated with variable bitterness of chloramphenicol and PROP, but not ofloxacin. The bitterness of ofloxacin associated with a TAS2R9 SNP (V187A). This pilot study provides novel evidence on differences in the bitterness from two antibiotics, which are associated with TAS2R variants. Improved understanding of individualized barriers to patient compliance, especially for oral formulations, can guide future efforts to optimize delivery systems for improved compliance.

Randomized Controlled Trial to Investigate the Effects of Repeated Exposure to Low Added Sugar Snacks Among Children: Choice of Experimental Food Stimuli

ObjectivesWhat we eat during childhood programs food preferences, yet from the age of two years, added sugar intake exceeds recommended levels. We are conducting a trial in which mother-child dyads are randomized to one of two groups that differ in the sweetness and added sugar content of afternoon snacks provided to toddlers and type of educational lessons given to their mothers. The present study describes the methods used to determine the types of snacks proffered to the control and intervention groups during the 4-month exposure period.MethodsWe established a priori that snacks for either group would differ in added sugar and sweetness without the inclusion of candy, low calorie sweeteners, or sugar sweetened beverages and would provide similar energy (300 kcal) at each snack occasion. We developed two menus. In the first menu, every snack occasion contained at least one food or beverage item, often made by the same manufacturer, for which there was a regular sugar version for control group and low-sugar version for the intervention group. In the second menu, we put less emphasis on matching the types of snacks for the two groups. Rather, we focused on the added sugar and salt content of the snacks and we provided additional snack occasions (∼4/month) of fresh fruit for the intervention group. A sensory panel evaluated the sweetness of the snacks using the general labelled magnitude scale.ResultsWhile both menus yielded snacks that differed in sweetness (p < 0.001) and sugar content (p < 0.001), the intervention snacks in the first menu contained twice the amount of sodium than the control snacks in the first menu (p < 0.001). Adding fruit and focusing on the sugar and sodium content per se resulted in the intervention snacks in the second menu containing significantly less sodium than those in the first menu (p < 0.001). Although there was only a one-fold difference between the intervention and control snacks in the second menu, the difference was significant, due in part to more savory snacks for the intervention group (p < 0.001).ConclusionsProviding low-sugar snacks to children requires attention to its salt content, another preferred taste of children. With increasing evidence suggesting the importance of early life experiences on long-term health, this trial will inform future prevention efforts for children.Funding SourcesSupported by NIH Grant R01DC016616.

Exploring the association between oral tactile sensitivity measures and phenotypic markers of oral responsiveness.

This study investigated the individual variability in oral tactile sensitivity considering touch, by means of Von Frey Hair monofilaments (VFH) and spatial resolution, using the grating orientation test (GOT). The relationships of the two measures with 6-n-propylthiouracil (PROP) responsiveness and fungiform papillae density and size were investigated. One hundred and forty-four subjects (48.6% women, aged 18-30) participated in the study. VFH and GOT thresholds were assessed by three-down/one-up staircase method. Responsiveness to 3.2 mM PROP was assessed on the general Labeled Magnitude Scale. Fungiform papillae density (FPD) and size were determined from automated counting. VFH thresholds appeared unsuitable to reveal individual variation in responsiveness to point-pressure on the tongue. The frequency of GOT thresholds approximated a normal distribution and covered the whole range of variation, thus indicating an ability to measure individual variation in oral tactile sensitivity. No significant linear correlations were found between any of the oral tactile sensitivity measures and PROP responsiveness, FPD total and size class. VFH and GOT thresholds were not significantly associated. Agglomerative hierarchical clustering was used to classify participants for their PROP responsiveness, total FPD and GOT threshold. Three clusters were identified, C1 (n=67), Cl2 (n=42), and Cl3 (n=35), differing for PROP responsiveness and FPD only. Results encourage future studies to explore association between GOT and both perception and preference for different food texture. Furthermore, deeper investigation of individual variability in sensitivity to different types of oral tactile stimuli would be helpful to capture differences in tactile sensitivity among the most sensitive individuals.

Human Oral Sensitivity to and Taste Modulation by 3-Mercapto-2-Methylpentan-1-ol.

Introduction3-Mercapto-2-methylpentan-1-ol (3 M) is a key onion flavor (aroma), but past sensory work has focused primarily on ortho-nasal presentation. A series of experiments was conducted to characterize human sensitivity to oral 3 M solutions, then determine how 3 M impacts perception of basic tastes.MethodsDetection thresholds were measured for a food grade, racemic mixture using a forced-choice staircase procedure (n = 19). Recognition was measured by presenting a single stimulus per trial (3 M, vanillin, or water), with “onion,” “vanilla,” or “water” as responses (n = 18). Supra-threshold intensity (n = 20) was measured for various concentrations using the general labeled magnitude scale (gLMS). Odor-taste interactions were studied using mixtures of 3 M and exemplars of basic tastes. Participants rated the intensity of basic tastes, or both taste and aroma, using the gLMS (n ranged from 10 to 15). All stimuli were in aqueous solution.ResultsParticipants detected oral 3 M at about 0.90 ppb and recognized 3 M as “onion” at about 5 ppb. Supra-threshold intensity increased roughly as a cumulative logistic function of concentration. 3 M enhanced the rated savory intensity of monosodium glutamate, but did not enhance the dominant qualities of exemplars of the other four basic tastes. Under a response-context more favorable to an analytic approach, savory enhancement was reduced but not eliminated. Savory enhancement was eliminated with nose-clips.ConclusionsOral sensitivity was lower than previous retronasal studies would suggest, but roughly consistent with concentrations in cooked allium varieties. Oral 3 M selectively enhanced savory intensity, an effect likely due to retronasal aroma rather than taste or mouthfeel.Implication3 M is a promising candidate aroma to enhance or impart a savory flavor.

Long-term combined exercises enhance sweet taste sensitivity and reduce carbohydrate intake in patients with type 2 diabetes mellitus

Background: The link between sweet taste perception and carbohydrate intake in diabetics who perform regular combined exercises has not been explored. Aims and Objectives: This study aimed at determining the impact of combined exercises on taste perception for sucrose and carbohydrate intake in patients with type 2 diabetes mellitus. Materials and Methods: A clinical trial was conducted with 225 patients with T2DM, aged 35–60 years assigned randomly into three groups; aerobic, combined, and a control group. Outcomes of the aerobic group were not reported. Combined group performed brisk walking 4–5 days/week and resistance exercises 2–3 days/week for 6 months. Supra-threshold intensity ratings, preference for sucrose, and carbohydrate intake assessed at baseline, at 3 and 6 months were measured using “general Labeled Magnitude Scale,” “Monell 2-series-forced choice method,” and a 3-day diet diary, respectively. Results: Ratings for the highest (combined vs. control: +3.15±0.57 vs. −7.96±0.40 mol/L, P=0.022) and the second-highest sucrose concentrations (combined vs. control: +7.79±4.49 vs. −8.98±0.99 mol/L, P=0.003) in the combined group were significantly higher with significant time × group interaction (2.02M: P=0.002, 0.64M: P=0.003). Preference for sucrose was lower in the combined group (combined vs. control: −0.08±0.14 vs. +0.01±0.03 mol/L, P=0.002), and the time × group interaction was not significant. Carbohydrate intake (combined vs. control: −46.97±21.60 vs. −6.30±9.36 g, P=0.001) and HbA1c level (combined vs. control: −0.66±1.81 vs. +0.33±1.84%, P=0.008) were reduced in the combined group, and taste sensitivity significantly predicted the carbohydrate intake with combined exercises (R2=0.64, P=0.01). Conclusion: Regular combined exercises increase sweet taste sensitivity for higher concentrations of sucrose. Taste sensitivity, not the preference determines the carbohydrate intake in exercising diabetics.

Cross-modal effect of capsaicin and pepper oleoresin on the enhancement of saltiness perception in a NaCl model solution

Reducing sodium scientifically and effectively without affecting the flavor and safety of food remains a challenge for food researchers. A few previous reports have shown that single capsaicin (C) and pepper oleoresin (P) modulate the saltiness perception and sodium reduction, respectively. However, there is a lack of research on whether combining the C + P has an interaction effect on saltiness enhancement. The cross-modal and interactive effect of C and P on the saltiness perception and NaCl reduction in a NaCl model solution at different concentrations (0.98 g/L ∼ 19.88 g/L) using the general labeled magnitude scale (gLMS) were investigated in this study. Results showed that single C or P had a significant saltiness enhancement effect at the low-to-medium NaCl concentration (0.98 g/L ∼ 4.44 g/L) solution. Importantly, it was confirmed for the first time that interactions of C and P can increase saltiness in a ternary water solution system with NaCl, C, and P significantly. And the combination of C and P enhanced the saltiness significantly at the moderate-to-high NaCl concentrations, and the maximum percentages of saltiness intensity enhancement and NaCl reduction reached 37.65% and 26.09%, respectively. This research not only provided valuable data regarding the modulating effect of the “má là” flavor on saltiness perception but also offer novel insights and a promising approach regarding sodium reduction strategies during the development of low-sodium food.

Fruit and vegetable liking and intake among college students: a cross-sectional study

ObjectiveThis study examined the liking of fruits and vegetables among college students and the relationship between skin carotenoid levels and liking of fruits and vegetables. Participants: Sixty-six undergraduate students enrolled at a university in the southeastern United States participated in this study beginning August 2019. Methods: Skin carotenoid levels were measured using the Veggie Meter® reflection spectroscopy device. Liking of individual fruits and vegetables was measured using a hedonic general Labeled Magnitude Scale. Results: There were significant differences in mean skin carotenoid levels by year of study and age group. Students had a very strong liking for potatoes and pineapple. Veggie Meter scores and overall liking for fruits and vegetables were positively correlated. Conclusions: In order to encourage the consumption of fruits and vegetables, preferences for specific fruits and vegetables as well as accessibility should be considered to better serve and accommodate college students.

An examination into the effect of genetic taste status and intensity of carbonation on swallowing and palatability in healthy young adults.

Dysphagia is a highly prevalent condition and affects a wide range of cohorts. A common compensatory strategy to manage dysphagia is diet modification. However, this technique is often associated with poor patient quality of life and adverse long-term effects. Carbonated liquids have shown promise as an alternative compensatory strategy for the management of dysphagia. To examine the effect of genetic taste status and intensity of carbonation on swallowing and palatability in a healthy young adult population. To examine the palatability of carbonated liquids over time. A total of 35 healthy young adults were recruited for this prospective, quantitative cohort study. They each drank 150 ml of still water (SW), lightly carbonated water (LCW) and highly carbonated water (HCW). Swallow function, palatability and genetic taste status were assessed using the timed water swallow test, the hedonic general labelled magnitude scale and participant ratings of the bitterness of propylthiouracil strips, respectively. Participants were divided into groups of supertasters, moderate tasters and non-tasters. A significant difference was found between SW and HCW on three tests of swallow function. Average time per swallow increased (p = 0.03), average swallow velocity decreased (p = 0.001) and average volume per swallow decreased (p = 0.017) on HCW compared with SW. HCW had a greater impact on swallow function than LCW. A significant mean difference in palatability ratings was found across intensity levels of carbonated fluids (p = 0.002), specifically between SW and HCW (p = 0.001). HCW was less palatable than SW. The palatability of carbonated liquids, investigated within a subgroup of five participants, did not decrease after a 24-h period during which participants only drank carbonated liquids (p = 0.102). A significant difference was found between supertasters' (n = 9) (mean = 13.33) and non-tasters' (n = 20) (mean = -24.5) palatability ratings of HCW (p = 0.03). Despite differences in swallow function between SW and HCW, no differences were detected between supertasters' and non-tasters' swallow function on SW, LCW or HCW. Carbonated liquids have the ability to alter swallow function in a healthy young adult population; however, liquids must be highly carbonated in order to have an effect. Additionally, highly carbonated liquids are less palatable than SW, but the palatability of carbonated liquids does not decrease over time. Furthermore, supertasters find HCW more palatable than non-tasters. These findings suggest that carbonated liquids alter swallowing in a healthy population. Further research in a clinical population is needed to better understand the potential role of sensory stimulation as a dysphagia intervention. What is already known on the subject Several studies have found that carbonated liquids have the ability to alter swallow function in both healthy and clinical populations. However, there is a lack of evidence around the optimum intensity of CO2 in carbonated liquids and the palatability of carbonated liquids as well as the palatability of carbonated fluids over time. What this paper adds to existing knowledge The findings from this study suggest that carbonated liquids can alter swallow function in a healthy young adult population, but liquids must be highly carbonated in order to have an effect. HCW is less palatable than SW, but the palatability of carbonated liquids does not decrease over time. Additionally, supertasters find HCW more palatable than non-supertasters (non-tasters). What are the potential or actual clinical implications of this work? The findings from this study suggest that carbonated liquids may be suitable for use as a sensory stimulation technique for people with dysphagia, as their palatability does not decrease over time; however, further research in a clinical population is needed in order to determine this. Additionally, intensity of stimulus is an important factor to consider during dysphagia evaluation to identify what intensity is required to optimize swallowing.

Individual Differences in Adaptation to Sweet Taste

ObjectivesOver-consumption of sugar-sweetened beverages is associated with obesity and related conditions, but low-calorie alternatives are rejected by most consumers. Individual differences in sensitivity to off tastes of low-calorie sweeteners (LCS) have been considered as a factor in consumer choice. However, potential differences in adaptation, i.e., the tendency for sweetness to wane with repeated sips, has received less attention. This study measured sweetness adaption to a sugar and two LCS in the same sample of healthy adults to determine if there are stable individual differences in sweet adaptation. MethodsStimuli included three sweeteners at concentrations corresponding to the low (500 mM glucose, 246 μM sucralose, and 303 μM RebA) and high (1.08 M glucose, 870 μM sucralose, and 823 μM RebA) end of the sweetness spectrum for most commercially sold beverages in the US. Each trial participants (n = 38) tasted seven, 10 mL samples of the same stimulus (10 s between samples). For each sample, participants rated sweetness intensity using a general Labeled Magnitude Scale. Tests for all stimuli were repeated three times, on separate days, to assess stability. ResultsAll sweeteners showed significant reduction in sweetness with repeated sips, with the exception of the higher concentration glucose (no significant decrease across repeated sips). Sweetness waned with repeated sips more profoundly for the two LCS than for glucose, as expected given previous results. Importantly, there were substantial and stable (across test sessions) individual differences in sweet adaptation. ConclusionsSweetness faded more rapidly and completely for LCS than for glucose, and some individuals were more susceptible to sweetness adaptation than others. Whether these individual differences are stable across longer periods of time, or contribute to individual differences in acceptance of beverages sweetened with LCS is currently unclear. Funding SourcesFunded by a consortium of food and ingredient companies, including Asahi, Kellogg, Kraft, Mondelez, and Suntory. The views expressed are those of the authors, and do not necessarily reflect the views of the sponsors.

Taste and Smell Function in Head and Neck Cancer Survivors.

Survivors of head and neck squamous cell cancers (HNSCC) frequently complain of taste dysfunction long after radiation therapy is completed, which contradicts findings from most sensory evaluation studies that predict dysfunction should resolve few months after treatment. Therefore, it remains unclear whether taste and smell function fully recovers in HNSCC survivors. We evaluated HNSCC survivors (n = 40; age 63 ± 12 years, mean ± standard deviation) who received radiation therapy between 6 months and 10 years before recruitment and compared their responses to those of a healthy control group (n = 20) equivalent in age, sex, race, smoking history, and body mass index. We assessed regional (tongue tip) and whole-mouth taste intensity perception using the general Labeled Magnitude Scale and smell function using the University of Pennsylvania Smell Identification Test (UPSIT). To determine possible differences between groups in retronasal smell perception, we used solutions of sucrose with strawberry extract, citric acid with lemon extract, sodium chloride in vegetable broth, and caffeine in coffee and asked participants to rate perceived smell and taste intensities with and without nose clips. We found groups had similar UPSIT and taste intensity scores when solutions were experienced in the whole mouth. However, HNSCC survivors were less likely to identify low concentrations of bitter, sweet, or salty stimuli in the tongue tip relative to healthy controls. Our findings suggest persistent and subtle localized damage to the chorda tympani or to the taste buds in the fungiform papillae of HNSCC survivors, which could explain their sensory complaints long after completion of radiotherapy.

The Associations Between Bitter and Fat Taste Sensitivity, and Dietary Fat Intake: Are They Impacted by Genetic Predisposition?

A relationship between bitter and fat taste sensitivity, CD36 rs1761667 and TAS2R38 has been demonstrated. However, research is scarce and does not take diet into account. This study aimed to explore associations between genetics, fat and bitter taste sensitivity and dietary fat intake in healthy UK adults. A cross-sectional study was carried out on 88 Caucasian participants (49 females and 39 males aged 35 ± 1 years; body mass index 24.9 ± 0.5 kg/m2). Bitter taste sensitivity was assessed using phenylthiocarbamide (PTC) impregnated strips and the general Labeled Magnitude Scale. Fat taste sensitivity was assessed by the Ascending Forced Choice Triangle Procedure and dietary intake with a semi-quantitative food frequency questionnaire. Genotyping for rs713598, rs1726866, rs10246939, and rs1761667 was performed. Participants with TAS2R38 PAV/PAV diplotype perceived PTC strips as more bitter than groups carrying AVI haplotypes (AVI/AVI, P = 1 × 10-6; AVI/AAV, P = 0.029). CD36 rs1761667 was associated with fat taste sensitivity (P = 0.008). A negative correlation between bitter taste sensitivity and saturated fat intake was observed (rs = -0.256, P = 0.016). When combining the CD36 genotypes and TAS2R38 diplotypes into one variable, participants carrying both TAS2R38 AVI haplotype and CD36 A allele had a higher intake of saturated fat compared to carriers of CD36 GG genotype or TAS2R38 PAV/PAV and PAV/AAV diplotypes (13.8 ± 0.3 vs. 12.6 ± 0.5%TEI, P = 0.047) warranting further exploration in a larger cohort.

Factors Associated with Sweet Taste Sensitivity in Patients with Type 2 Diabetes Mellitus (T2DM)

Introduction: Taste sensitivity plays a vital role in determining food preferences. Evidence suggests that patients with diabetes are less sensitive to sweet taste. Increased sugar consumption due to low sensitivity adversely affect the glycemic control in Type 2Diabetes Mellitus (T2DM). Although the factors associated with taste sen­sitivity have been assessed in healthy individuals, it is less reported in T2DM. Thus, the aim of this study was to determine the factors associated with taste sensitivity for sucrose in patients with T2DM.Method: A sample of 111 patients, aged between 35-60 years, having T2DM for &gt; 5 years were considered. Baseline sociodemographic and anthropometric parameters were obtained. Supra-threshold intensity ratings for a range of sucrose concentrations were assessed using ‘general Labeled Magnitude Scale’. HbA1c was deter­mined at recruitment. Data was analyzed using Multiple Linear Regression.Results: Results showed that in patients with T2DM,a significant association was evident between the supra­threshold intensity ratings for the highest concentration of sucrose (2.02M) tested and the waist circumference (p=0.022), hip circumference (p=0.039) and waist-hip ratio (p=0.022). None of the other factors were signifi­cantly associated with either the highest or any other concentration tested.Conclusion: Reduction in waist circumference, hip circumference and waist hip ratio is likely to improve the sweet taste sensitivity in T2DM patients and vice versa. Maintaining these parameters within healthy limits may helpachieving a better glycemic profile through reducing the sugar consumption in patients with T2DM.

Addition of a visual cue to rice increases perceived flavour intensity but not liking

Rice is a common staple for about 50% of the world population. Sodium based ingredients such as table salt (NaCl) and mono-sodium glutamate (MSG) are often added to rice to increase flavour intensity and subsequent liking. Due to negative health consequences of excessive NaCl consumption and negative consumer perception of MSG, alternative strategies to increase perceived flavour intensity of rice are needed. As such, the present research aimed to investigate the effect of a visual product cue on perceived flavour intensity and liking of rice. In a within-subject, randomised design, 151 participants tasted six different rice samples (i.e., with and without a visual cue, at 0%, 0.05% and 0.1% MSG concentrations). Next, they rated perceived flavour intensity (rank-order and general labelled magnitude scale measures), liking (9-point hedonic scale) and preference (rank-order), over two sessions separated by one week. Across all MSG concentrations, the presence of the visual cue significantly increased reported perceived flavour intensity. No effect of the visual cue on liking nor preference were found. In conclusion, a visual product cue increased perceived flavour intensity of rice, but not liking or preference.

Erring Experts? A Critique of Wine Ratings as Hedonic Scaling

AbstractConsumers use expert ratings to help choose wine, and economists find correlations between ratings and transaction prices. Rating scales resemble hedonic scales in the behavioral sciences, which suffer from an “intersubjectivity” problem. Taste is a private sensation; people taste differently (an external validity problem), so ratings are often unreliable hedonic markers of enjoyment. But why? Hedonic measurements from food science (“general Labeled Magnitude Scales”) attempt to adjust for differences in perceived sensory sensitivity and offer clues. Resulting insights illustrate wine ratings’ shortcomings as reliable guides to enjoyment. (JEL Classifications: C14, D12, D91, L15, L66)