Sweetness Intensity Research Articles

A receptor-based assay to study the sweet and bitter tastes of sweeteners and binary sweet blends: The SWEET Project.

Sweeteners are used in the food industry to provide sweetness similar to sugar and to decrease the caloric intake and risks associated with obesity. However, some sweeteners are characterised by bitter, metallic and other off-tastes. Sensory and cellular studies have demonstrated synergies between sweetener blends, which are responsible for enhancing sweetness. This study aimed to identify new sweetener blends that are able to enhance sweetness intensity without causing bitter off-taste using in vitro functional expression of taste receptors. The dose-response of the sweet taste receptor (TAS1R2/TAS1R3) was determined for sucrose and 9 sweeteners and was consistent with their sweetness potency. Stimulation of TAS1R2/TAS1R3 by 6 binary sweetener blends confirmed 3 known synergies determined by sensory analysis, including sucralose/acesulfame-K, rebaudioside A/erythritol and rebaudioside A/thaumatin, and revealed 2 new synergies, known as, neotame/D-allulose and mogroside V/thaumatin. No synergy was observed for the rebaudioside M/mogroside V blend, probably due to their common binding sites on the sweet taste receptor. The ability of the 9 selected sweeteners to activate the 25 human bitter taste receptors (TAS2Rs) was tested. The cellular based assay demonstrated that sucralose, acesulfame-K, rebaudioside A, mogroside V and D-allulose activated at least 2 TAS2Rs. Sucralose, acesulfame-K and rebaudioside A exhibited lower EC50 values for TAS1R2/TAS1R3 than for TAS2Rs, which may explain their absence of bitter off-taste at low concentrations, unlike mogroside V and D-allulose. Our data provide a receptor-based understanding of the complex synergies among sweetener blends and an effective approach for testing new sweeteners while avoiding the activation of TAS2Rs.

Change in liking following reduction in sweetness level of carbonated beverages: a randomized controlled parallel trial.

Despite recommendations to reduce sweet-tasting foods and beverage consumption, there is limited understanding of our ability to adapt to a less sweet diet and the optimal method for doing so. Thus, we conducted two parallel, double-blind, randomized controlled trials in the USA and Mexico to investigate whether different methods of reducing sweetness could change sweetness preferences. Over 6 months, habitual consumers of full-sugar sweetened (FSS-CSD) or low-calorie sweetened carbonated soft drinks (LCS-CSD) consumed a full sweetness CSD (Control), CSD with gradually decreasing sweetness levels (StepR), and a reduced sweetness test CSD (DirR). The StepR and DirR methods were similarly effective in helping the USA FSS-CSD cohort maintain their preference for reduced-sweetness CSD, without affecting sweetness intensity perception. However, neither method significantly impacted the sweetness intensity perception or preference of the USA LCS-CSD cohort, and the FSS-CSD and LCS-CSD cohorts in Mexico. Nevertheless, participants from both sweetness reduction groups in all cohorts were more willing to purchase reduced sweetness CSD compared to Control, underscoring the potential for consumer acceptance of less sweet beverages regardless of adaptation strategies.This trial was registered at www.clinicaltrials.gov as NCT04609657 and NCT05010408.

Liking for Sweet Taste, Sweet Food Intakes, and Sugar Intakes.

Sweet taste preferences are currently targeted to aid with reducing free sugar intakes, but associations between sweet taste liking, sweet food intakes, and sugar intakes are not well established. UK consumers (n = 179) who were consuming >5% of total energy intakes from free sugars provided several laboratory measures of sweet taste liking, laboratory test meal measures of sweet food choice and sugar intakes, and 3-day food diary measures of free-living free sugar and total sugar intakes. Liking measures included liking for a 1 M sucrose solution, and pleasantness, desire to eat, and sweet taste intensity ratings for seven foods of a range of sweet taste intensities in a taste test. Wide individual differences in sweet taste liking, in liking for a high sweet taste intensity, and in the relationships between sweet taste intensity and sweet taste liking were found. The majority of participants confirmed high liking and increasing liking for increasingly sweet tastes, but differing patterns of responses were also found. Higher liking for sweet foods was associated with increased sweet food selection and consumption at the test meal, and to some degree with free sugar and total sugar consumption in this restricted scenario. However, we found no associations between sweet taste liking, regardless of measure, and either free-living free sugar or total sugar intakes. These findings cast doubt on assumptions that sweet taste preferences are high for all and that these high sweet taste preferences drive high free sugar intakes.

Quantifying the sweetness intensity and impact of aroma in honey from four floral sources.

Unlike many commercial sweeteners for which sweetness dose-response curves have been constructed, honey's sweetness has yet to be quantified. Honey differs from most commercial sweeteners in that it has a robust aroma; this aroma may impact its perceived sweetness. This study quantified the sweetness intensity and the impact of aroma on the perceived sweetness of four different honey varieties (clover, wildflower, alfalfa, and orange) compared to sucrose. Each sweetener evaluated was diluted to six concentrations in water ranging from 12.5g/L to 125g/L. Panelists (n=55) rated the sweetness intensities with and without aroma, in replicate, on the Global Sensory Intensity Scale. Additionally, the volatile organic compounds in the honey samples were profiled using gas chromatography-mass spectrometry (GC/MS) analysis. Honey and sugar were equivalently sweet at a given concentration (g/L), with aroma present (p=0.251). Additionally, honey and sugar were not equivalently sweet without aroma; aroma significantly increased sweetness intensities for all sweeteners (p=0.042) and especially honeys. In a 100g/L solution, the aromas in honey increased its sweetness by 23%-43%, depending on the floral source. Compounds with sweet aroma characteristics were identified at high concentrations in all honey samples using GC/MS analysis, including furfural, benzaldehyde, benzene acetaldehyde, and dimethyl sulfide. Additionally, (S)-limonene and toluene were present in high quantities in the orange and alfalfa samples. This study can inform appropriate honey usage levels and identify major volatiles that may enhance sweetness. PRACTICAL APPLICATION: Honey sweetness has not been determined quantitatively, despite the widespread use of honey among consumers and product formulators. Sweetness enhancement by honey aroma volatiles may support a reduction in added sugars while maintaining sweetness intensity.

Suppression of the postprandial hyperglycemia in patients with type 2 diabetes by a raw medicinal herb powder is weakened when consumed in ordinary hard gelatin capsules: A randomized crossover clinical trial.

Contradictory claims about the efficacy of several medicinal plants to promote glycemic control in patients with type 2 diabetes mellitus (T2DM) have been explained by divergences in the administration form and by extrapolation of data obtained from healthy individuals. It is not known whether the antidiabetic effects of traditional herbal medicines are influenced by gelatin capsules. This randomized crossover trial aimed to evaluate the acute effect of a single dose of raw cinnamon consumed orally either dissolved in water as a beverage or as ordinary hard gelatin capsules on postprandial hyperglycemia (>140 mg/dL; >7.8 mmol/L) in T2DM patients elicited by a nutritionally-balanced meal providing 50 g of complex carbohydrates. Fasting T2DM patients (n = 19) randomly ingested a standardized meal in five experimental sessions, one alone (Control) and the other after prior intake of 3 or 6 g of crude cinnamon in the form of hard gelatin capsules or powder dissolved in water. Blood glucose was measured at fasting and at 0.25, 0.5, 0.75, 1, 1.5 and 2 hours postprandially. After each breakfast, its palatability scores for visual appeal, smell and pleasantness of taste were assessed, as well as the taste intensity sweetness, saltiness, bitterness, sourness and creaminess. The intake of raw cinnamon dissolved in water, independently of the dose, decreased the meal-induced large glucose spike (peak-rise of +87 mg/dL and Δ1-hour glycemia of +79 mg/dL) and the hyperglycemic blood glucose peak. When cinnamon was taken as capsules, these anti-hyperglycemic effects were lost or significantly diminished. Raw cinnamon intake did not change time-to-peak or the 2-h post-meal glycaemia, but flattened the glycemic curve (lower iAUC) without changing the shape that is typical of T2DM patients. This cinnamon's antihyperglycemic action confirms its acarbose-like property to inhibit the activities of the carbohydrate-digesting enzymes α-amylases/α-glucosidases, which is in accordance with its exceptionally high content of raw insoluble fiber. The efficacy of using raw cinnamon as a diabetes treatment strategy seems to require its intake at a specific time before/concomitantly the main hyperglycemic daily meals. Trial registration: Registro Brasileiro de Ensaios Clínicos (ReBEC), number RBR-98tx28b.

Quality-Driven Design of Pandan-Flavored Sponge Cake: Unraveling the Role of Thermal Processing on Typical Pandan Aroma.

Pandan (Pandanus amaryllifolius Roxb.) has been used in the production of bakery goods either as a functional ingredient or a natural flavoring that, when roasted, exerts a fragrant rice-like aroma and an attractive green color. This study elucidated the typical aroma compounds from pandan leaves and explored the influence of thermal treatments on their aroma profiles using GC-O-MS, E-nose, and GC-IMS analyses. The effects of formulation and baking conditions on the qualities of pandan-flavored sponge cake were comprehensively evaluated through a holistic approach covering several aspects including cake batter gravity, color, texture, and sensory characteristics. The baking treatment introduced more types of pleasant aromas (9 aromas vs. 17 aromas) and increased the odor intensities of the original volatile compounds, especially for the roasted and steamed rice-like odors. The increased amount of pandan flavoring reshaped the color of the cake crumb (especially for the L* and a* spaces) and significantly decreased the hardness (3.87 N to 1.01 N), gumminess (3.81 N to 0.67 N), and chewiness (13.22 mJ to 4.56 mJ) of the sponge cake. The perceived intensities of bitterness and sweetness can be adjusted by modulating the levels of 2-phenylethanol, 2-methyl-1-butanol, hexyl alcohol, and decanal, along with the total alcohols and aldehydes, due to their significant correlations revealed by correlation heatmap analyses.

Neural processing of sweet taste in reward regions is reduced following bariatric surgery.

Bariatric surgery reduces sweet-liking, but mechanisms remain unclear. We examined related brain responses. A total of 24 nondiabetic bariatric surgery and 21 control participants with normal weight to overweight were recruited for an observational controlled cohort study. They underwent sucrose taste testing outside the scanner followed by stimulation with 0.40M and 0.10M sucrose compared with water during functional magnetic resonance imaging. A total of 21 bariatric participants repeated these procedures after surgery. Perceived sweet intensity was not different among the control, presurgery, or postsurgery groups. Bariatric participants' preferred sweet concentration decreased after surgery (0.52M to 0.29M; p = 0.008). Brain reward system (ventral tegmental area, ventral striatum, and orbitofrontal cortex) region of interest analysis showed that 0.40M sucrose activation (but not 0.10M) decreased after surgery. Sensory region (primary somatosensory and primary taste cortex) 0.40M sucrose activation was unchanged by surgery and did not differ between control and bariatric participants. Primary taste cortex activation to 0.10M sucrose solution was greater in postsurgical bariatric participants compared with control participants. Bariatric surgery reduces the reward system response to sweet taste in women with obesity without affecting activity in sensory regions, which is consistent with reduced drive to consume sweet foods.

Sensory analysis of the flavor profile of full immersion hot, room temperature, and cold brewed coffee over time

With the growing popularity of cold brewed coffee comes a need for brewing efficiency while preserving the desirable flavor profile. Despite the wide use of full immersion brewing techniques, the effect of brew time on the dynamic sensory profiles of full immersion brewed coffee remains underexplored. Here, we investigated the relationship between coffee sensory quality and extraction dynamics, measured as Total Dissolved Solids (TDS) and Extraction (E) of full immersion brewed coffee at various roast levels, and brewing temperatures (4 °C, 22 °C and 92 °C), over brew time using a generic descriptive analysis method. Specifically, different brew time points were selected for different temperatures based on five targeted coffee extraction stages. Furthermore, the unique experimental design also explored a sensory-driven engineering research process. Roast level had the greatest impact on the sensory profile of the coffees, followed by brewing temperature, but brew time, especially the longer brew times as TDS plateaued, had subtler impacts than expected. Twenty-five of 28 sensory attributes were significantly different among the 30 coffee samples, indicating a single source green coffee blend can produce a wide range of complex sensory profiles using different combinations of roast level, temperature, and brew time. Specifically, the intensity of sweetness was negatively correlated with TDS, and 19 other attribute intensities were positively correlated with TDS. Interestingly, we found that certain long time cold brews had similar sensory profiles to those of some short time hot brews, suggesting the sensory profiles of certain hot brews and cold brews could possibly be matched through controlled preparation. Overall, our study demonstrated an approach of integrating food engineering and sensory analysis for product development, and our findings provide valuable insights into the extraction dynamics and sensory quality of full immersion brewed coffee and opens new brewing avenues for the coffee industry.

New Sweet-Tasting Gypenosides from "Jiaogulan" (Gynostemma pentaphyllum) and Their Interactions with the Homology Model of Sweet Taste Receptors.

Gynostemma pentaphyllum has been used as an herbal tea, vegetable, and dietary supplement for hundreds of years in East Asia. The sweet variety, grown in large areas in Fujian Province, China, is an essential source of "Jiaogulan" herbal tea. However, its sweet components are unknown. To investigate the sweet constituents of Fujian "Jiaogulan" and discover new natural high-potency sweeteners, phytochemical and sensory evaluations were combined to obtain 15 saponins, of which 11 (1-11) were sweet-tasting, including 2 new ones with sweetness intensities 20-200 times higher than that of sucrose, and four (12-15) were bitter-tasting. Their structures were elucidated using spectroscopic methods (NMR, MS, IR, UV), hydrolysis, and comparison with literature data. The contents of the 15 saponins were quantitatively analyzed using UPLC-MS/MS in multiple reaction monitoring mode. The contents of 1 and 2 sweet-tasting gypenosides were 9.913 ± 1.735 and 35.852 ± 1.739 mg/kg, respectively. The content of the sweetest compound (6) was 124.969 ± 0.961 mg/kg. Additionally, compound 4 was the most abundant sweet component (422.530 ± 3.702 mg/kg). Furthermore, molecular docking results suggested interactions of sweet saponins with sweet taste receptors. In general, this study revealed the material basis of the Fujian "Jiaogulan" taste.

Willingness to Pay for Blueberries: Sensory Attributes, Fruit Quality Traits, and Consumers’ Characteristics

Understanding consumers’ preferences for fruit quality attributes is key to informing breeding efforts, meeting consumer preferences, and promoting increased market demand. The objective of this study was to assess the effect of fruit quality traits and hedonic sensory evaluation on consumers’ willingness to pay (WTP) for a selection of fresh northern and southern highbush blueberry cultivars. The WTP was elicited by using a double-bounded contingent valuation conducted in conjunction with a consumer sensory test. Two types of models were estimated using either sensory evaluations (i.e., consumer preference and consumer intensity) or instrumental measurement data (i.e., measures of soluble solids, titratable acidity, sugars, acids, and firmness) as explanatory variables to model WTP. Results using sensory evaluations indicated that flavor liking, flavor intensity, and sweetness intensity are key factors that influence consumers’ acceptance and WTP for blueberries. A regression analysis using instrumental measurements indicated that measures related to sweetness and acidity traits are important factors that determine WTP. Higher WTP was associated with higher total sugar content across different levels of total organic acid. The WTP increases with organic acid content, because this is needed for enhanced flavor; however, WTP declines at high concentrations of organic acid. Except for extreme values of firmness, the WTP increased as measures of fruit firmness increased, indicating a consumer preference for firmer blueberries. Overall, the results provided new insights into the relationships between consumer preference and WTP and fruit quality benchmarks to select for improved quality.

Mechanism of key volatiles in osmanthus scented green tea on the improvement of its aroma and taste quality

The intensity of green tea's floral and sweet flavors was enhanced after being scented by osmanthus (OSGT). However, the mechanism of flavor enhancement by key volatiles remains unknown. Here, the role of key volatiles in OSGT on aroma and taste was explored by sensory experiment-guided flavor analysis. Binary mixed models of (E)-β-ionone, dihydro-β-ionone, and α-ionone showed additive interactions on floral aroma enhancement, the interactions were increased with increasing concentrations. At the concentration in OSGT, binary mixed models of (E)-β-ionone, geraniol, linalool, and γ-decalactone showed additive interactions on sweet aroma enhancement. (E)-β-ionone, geraniol, linalool, and γ-decalactone all significantly increased the perceived intensity of sweetness of sucrose solutions. Additionally, molecular docking revealed the perception mechanism of olfactory and taste receptors to the above characterized volatiles, with hydrogen bonding and hydrophobic interactions being the main interactions. This study highlights the importance of characteristic volatiles in enhancing the flavor of OSGT.

Secondary Analysis of Sweetness Liking from Pilot Study Replacing Sugar Sweetened Soda with Flavored, Unsweetened Sparkling Water

Objective This study aimed to evaluate changes in sensory ratings (liking, sweetness intensity, “just about right” (JAR) level of sweetness) of 0–10.7% w/w sugar in soda after 1 and 2 wk of replacing sugar-sweetened soda consumption with unsweetened, flavored, sparkling water. Methods Consumers of sugar-sweetened sodas (17 men and women, average age 28 years) replaced their sodas with unsweetened, flavored sparkling waters for 2 wk. Changes in sensory ratings were evaluated for sodas ranging from 0–10.7% w/w added sugar. In a secondary analysis, cluster analysis identified “Sweet Likers” (liking increased with sugar concentration) and “Sweet Moderates” (liking peaked in the middle of the concentration range) in the baseline ratings, and models for changes in sensory ratings were reevaluated by sweet-liking group. Results The primary analyses showed no significant effects of the intervention on sweetness intensity or liking ratings. However, the secondary analysis showed that Sweet Likers reduced liking ratings for all sodas, but particularly for the highest concentration (p = 0.0021) after the intervention. Sweet Moderates, however, increased liking ratings after the intervention, driven by an increase in liking for the lower concentrations of sugar (p = 0.0058). Additionally, Sweet Moderates increased their overall ratings for sweetness intensity in sodas (p = 0.00074). Conclusion These results suggest that the intervention may have been more successful in shifting sensory perception and acceptance of less-sweet sodas for Sweet Moderates than for Sweet Likers. These results should be verified in a larger sample that intentionally recruits by sweet liker status, to see if initial liking for sweetness may be a critical factor in interventions aiming to improve liking of less sweet beverages.

Sex differences in appeal, reward, and sensory experience of E-cigarette flavors among adults who smoke cigarettes

ObjectiveFlavors enhance nicotine e-cigarette appeal by altering sensory experience. Females may be more sensitive to tobacco-associated cues and uniquely affected by flavor. The current study is an exploratory analysis to examine differences by sex on reward, appeal, and sensory experience of popular e-cigarette flavors. MethodsAdults (N = 121) who use cigarettes (≥1 cigarette/day) were enrolled in a laboratory study in which they vaped four e-cigarette flavors (tobacco, cherry, menthol, vanilla; in separate lab sessions) in one of two freebase nicotine concentrations (6 mg/ml,18 mg/ml). Following exposures, participants rated e-cigarette reward using the Drug Effects Questionnaire (DEQ), flavor and overall e-cigarette appeal using Labeled Hedonic Scales (LHS), and intensity of flavor, irritation, coolness, fruitiness, and sweetness using Generalized Labeled Magnitude Scales (gLMS). Linear mixed models were conducted for outcomes to analyze effects of sex, flavor, and sex x flavor interaction. ResultsFor DEQ ratings, there was a trend (p = .08) toward a sex x flavor interaction, in which menthol flavor produced more reward than other flavors for females, but not males. For LHS ratings, there was a significant sex x flavor interaction (p = .03) for overall e-cigarette experience with females but not males rating menthol higher than other flavors. All gLMS scales but irritation showed that females generally had greater differences between flavors compared to males (ps ≤ 0.03). ConclusionMenthol in e-cigarettes may play an important role in mediating appeal and/or reward among females. This may be due in part to their ability to better detect sensory effects of e-cigarettes.

Expression of a single-chain monellin (MNEI) mutant with enhanced stability in transgenic mice milk.

Monellin is a sweet protein that may be used as a safe and healthy sweetener. However, due to its low stability, the application of monellin is currently very limited. Here, we describe a wild-type, a double-sites mutant (E2N/E23A) and a triple-sites mutant (N14A/E23Q/S76Y) of single-chain monellin (MNEI) expressed in transgenic mice milk. Based on enzyme-linked immunoassay (ELISA), Western blot, and sweetness intensity testing, their sweetness and stability were compared. After boiling for 2min at different pH conditions (2.5, 5.1, 6.8, and 8.2), N14A/E23Q/S76Y-MNEI showed significantly higher sweetness and stability than the wild-type and E2N/E23A-MNEI. These results suggest that N14A/E23Q/S76Y-MNEI shows remarkable potential as a sweetener in the future.

Neural responses to oral administration of erythritol vs. sucrose and sucralose explain differences in subjective liking ratings

IntroductionHigh sugar intake is associated with many chronic diseases. However, non-caloric sweeteners (NCSs) might fail to successfully replace sucrose due to the mismatch between their rewarding sweet taste and lack of caloric content. The natural NCS erythritol has been proposed as a sugar substitute due to its satiating properties despite being non-caloric. We aimed to compare brain responses to erythritol vs. sucrose and the artificial NCS sucralose in a priori taste, homeostatic, and reward brain regions of interest (ROIs). MethodsWe performed a within-subject, single-blind, counterbalanced fMRI study in 30 healthy men (mean ± SEM age:24.3 ± 0.8 years, BMI:22.3 ± 0.3 kg/m2). Before scanning, we individually matched the concentrations of both NCSs to the perceived sweetness intensity of a 10% sucrose solution. During scanning, participants received 1 mL sips of the individually titrated equisweet solutions of sucrose, erythritol, and sucralose, as well as water. After each sip, they rated subjective sweetness liking. ResultsLiking ratings were significantly higher for sucrose and sucralose vs. erythritol (both pHolm = 0.0037); water ratings were neutral. General Linear Model (GLM) analyses of brain blood oxygen level-depended (BOLD) responses at qFDR<0.05 showed no differences between any of the sweeteners in a priori ROIs, but distinct differences were found between the individual sweeteners and water. These results were confirmed by Bayesian GLM and machine learning-based models. However, several brain response patterns mediating the differences in liking ratings between the sweeteners were found in whole-brain multivariate mediation analyses. Both subjective and neural responses showed large inter-subject variability. ConclusionWe found lower liking ratings in response to oral administration of erythritol vs. sucrose and sucralose, but no differences in neural responses between any of the sweeteners in a priori ROIs. However, differences in liking ratings between erythritol vs. sucrose or sucralose are mediated by multiple whole-brain response patterns.

The effects of sugar substitution with cinnamon powder in moringa jelly candy

This study aimed to evaluate the effects of sugar substitution with cinnamon powder (CP) on moringa jelly candy (MJC). Four MJC formulations were made based on the level of sugar substitution using 0%, 7.5%, 15%, and 22.5% CP, coded as control, F1, F2, and F3, respectively. Samples were then analyzed for nutritional content, water activity, color, texture, antioxidant activity (using the DPPH (2,2-Diphenyl-1-picrylhydrazyl (DPPH) method), sweetness intensity (using 9-scales rating test), sensory acceptance (using 9-point hedonic test), and sensory profile (using CATA/Check-All-That-Apply). Substituting sugar with CP significantly increased moisture content, antioxidant activity, and hedonic acceptance but significantly decreased the total sugars and calories. However, no significant effects were observed on hardness, water activity, and protein content. Based on the De Garmo effectiveness index, 15% sugar substitution with CP (F2) resulted in the optimum MJC formulation having moisture content 30.71%, protein content 12.59%, total Brix (sugar) 62.00%, total calories 277.04 kcal/100 g, hardness 13.47 N, lightness (L*) 34.63, water activity 0.90, antioxidant activity 83.13%, and the overall liking score 5.34 (neither like nor dislike). The F2 had medium sweetness intensity (5.54), which was not statistically different from the control. The F2 sensory profile was in the opposite quadrant against control and positively correlated with cinnamon taste and aroma, which were also highly associated with product liking. This result indicates that CP is promising as a sugar substitute and to improve the sensory acceptance of MJC by masking the undesirable moringa flavor.

Verbal descriptions modulate flavour perception and evaluation of wine: An exploratory study using Riesling and Muscat Bailey A wines

Significant efforts have been made in the wine industry to assist customers in making purchase decisions and enhance their drinking experience by providing verbal descriptions of the complex sensory characteristics of wine. However, the influence of such verbal descriptions on wine flavour perception and evaluation has not been examined. To fill this gap, this exploratory study performed an experiment using white Riesling wine from the 2021 German vintage and red Muscat Bailey A (MBA) wine from the 2019 Japanese vintage. Forty-six Japanese individuals (23 social drinkers and 23 wine experts) participated and were presented with two glasses of Riesling wine and two glasses of MBA wine with different verbal descriptions. One glass of Riesling/MBA wine was served with a description including its distinct aroma descriptor (i.e., a ‘petrol’ note for the Riesling wine and a ‘strawberry candy’ note for the MBA wine). For the other glass, the description did not include the descriptor. The participants were asked to taste the wines and rate their palatability, perceived sweetness intensities, acidity, astringency, alcohol sensation, body, and expensiveness on a 7-point scale. The results demonstrated that the social drinkers rated the Riesling wine with the ‘petrol’ descriptor as heavier-bodied and more expensive compared to the same wine without the descriptor. The wine experts were not as influenced as the social drinkers, but the experts rated the Riesling wine with the ‘petrol’ descriptor as less expensive. In the case of MBA wine with the ‘strawberry candy’ descriptor, the social drinkers rated it as more expensive, whereas the wine experts rated it as more palatable than the same wine without the descriptor. The results indicated that verbal descriptions of wine aroma indeed modulated the flavour perception and evaluation of wine, but the modulation effect varied between social drinkers and wine experts.

Influence of Abiotic and Biotic Elicitors on Organogenesis, Biomass Accumulation, and Production of Key Secondary Metabolites in Asteraceae Plants.

The medicinal plants of the Asteraceae family are a valuable source of bioactive secondary metabolites, including polyphenols, phenolic acids, flavonoids, acetylenes, sesquiterpene lactones, triterpenes, etc. Under stressful conditions, the plants develop these secondary substances to carry out physiological tasks in plant cells. Secondary Asteraceae metabolites that are of the greatest interest to consumers are artemisinin (an anti-malarial drug from Artemisia annua L.-sweet wormwood), steviol glycosides (an intense sweetener from Stevia rebaudiana Bert.-stevia), caffeic acid derivatives (with a broad spectrum of biological activities synthesized from Echinacea purpurea (L.) Moench-echinacea and Cichorium intybus L.-chicory), helenalin and dihydrohelenalin (anti-inflammatory drug from Arnica montana L.-mountain arnica), parthenolide ("medieval aspirin" from Tanacetum parthenium (L.) Sch.Bip.-feverfew), and silymarin (liver-protective medicine from Silybum marianum (L.) Gaertn.-milk thistle). The necessity to enhance secondary metabolite synthesis has arisen due to the widespread use of these metabolites in numerous industrial sectors. Elicitation is an effective strategy to enhance the production of secondary metabolites in in vitro cultures. Suitable technological platforms for the production of phytochemicals are cell suspension, shoots, and hairy root cultures. Numerous reports describe an enhanced accumulation of desired metabolites after the application of various abiotic and biotic elicitors. Elicitors induce transcriptional changes in biosynthetic genes, leading to the metabolic reprogramming of secondary metabolism and clarifying the mechanism of the synthesis of bioactive compounds. This review summarizes biotechnological investigations concerning the biosynthesis of medicinally essential metabolites in plants of the Asteraceae family after various elicitor treatments.

Differences in time-intensity sensory profiles of sweet taste intensity of glucose between older and young adults.

To understand age-related changes in sweet taste perception in daily life, it is important to understand taste intensity at the suprathreshold level. Previous studies have attempted to characterize the temporal aspects of human taste perception in terms of time-intensity evaluations. The perception of dynamic taste intensity in older adults increases slowly for salty taste; however, there have been no previous studies on time-intensity sensory evaluation of sweet taste in older adults. We hypothesized that older adults perceive sweet taste intensity more slowly than young adults. Fifty young and 40 older adults participated in the study and glucose solutions of 0.6 M and 1.5 M were used as stimuli. The study comprised two experiments: (1) a cup tasting test (static taste perception in the mouth), and (2) a time-intensity sensory evaluation, in which the solutions were presented using a custom-made delivery system. The intra-oral device was made to fit each participant's dentition. Further, the level of gag reflex was taken into consideration for each participant in the design of the intra-oral device. A suction tube was placed across the posterior tongue near the throat to remove solution and saliva. The solution delivery system was controlled by an original computer program. Older adults presented significantly different maximum intensity timing and slope for both concentrations compared with young adults (slope for 1.5 M, p < 0.01; others, p < 0.05). No significant differences were found between the older and young adults for reaction timing and maximum intensity. We conclude that older adults perceived sweetness more slowly than young adults, and ultimately perceived almost the same intensity as young adults. This is the first reported characterization of the time-intensity profile of sweet taste intensity of glucose in older adults. Using a standardized system enabled us to assess and compare feedback on taste intensities among different age groups in real-time. Based on this, we recommend older adults "savor" to perceive sweet tastes at the same level experienced by young adults.

New Insights into the Umami and Sweet Taste of Oolong Tea: Formation of Enhancer N-(1-carboxyethyl)-6-(hydroxymethyl) pyridinium-3-ol (Alapyridaine) in Roasting Via Maillard Reaction.

Roasting is pivotal for enhancing the flavor of Wuyi rock tea (WRT). A study investigated a novel compound that enhances the umami taste of WRT. Metabolomics of Shuixian tea (SXT) and Rougui tea (RGT) under light roasting (LR), medium roasting (MR), and heavy roasting (HR) revealed significant differences in nonvolatiles compounds. Compared LR reducing sugars and amino acids notably decreased in MR and HR, with l-alanine declining by 69%. Taste-guided fractionation identified fraction II-B as having high umami and sweet intensities. A surprising taste enhancer, N-(1-carboxyethyl)-6-(hydroxymethyl) pyridinium-3-ol (alapyridaine), was discovered and identified. It formed via the Maillard reaction, positively correlated with roasting in SXT and RGT. Alapyridaine levels were highest in SXT among the five oolong teas. Roasting tea with glucose increased alapyridaine levels, while EGCG inhibited its formation. HR-WRT exhibited enhanced umami and sweet taste, highlighting alapyridaine's impact on WRT's flavor profile. The formation of alapyridaine during the roasting process provides new insights into the umami and sweet perception of oolong tea.