Temporal dominance of sensations and sensory profiling: A comparative study

Investigation of the multiple taste enhancement properties of N-succinyl-amino acids and their relationship to chemical structure using dynamic sensory techniques

The present study aimed to explore the similarity and difference in taste enhancement properties of N-succinyl-L-phenylalanine (N-Suc-Phe), N-succinyl-L-tryptophan (N-Suc-Trp), and N-succinyl-L-tyrosine (N-Suc-Tyr) using temporal dominance of sensations (TDS), temporal check-all-that-apply (TCATA), and time-intensity (TI) techniques. Meanwhile, leading taste enhancers in the market, such as N'-[(2,4-dimethoxyphenyl)methyl]-N-(2-pyridin-2-ylethyl) oxamide (DE) was chosen to conduct a comparative analysis with the aforementioned three compounds. Findings from TDS and TCATA revealed that all compounds under investigation notably enhanced umami and saltiness while reducing bitterness in a concentration-dependent fashion (0.25-1 mg/L). Additionally, the TI results indicated that the duration of umami was extended by 50-75%, and the duration of bitterness was decreased by 20-40% upon addition of DE, N-Suc-Phe, N-Suc-Trp, and N-Suc-Tyr (1 mg/L). Among these, N-Suc-Trp was identified as the most effective in augmenting umami and mitigating bitterness, whereas N-Suc-Tyr excelled in enhancing saltiness intensity. Partial least squares regression (PLSR) pinpointed the carbon‑carbon double bond as the important structure influencing the enhancement of umami and reduction of bitterness, whereas the phenolic hydroxyl group was identified as critical for enhancing saltiness. This investigation provided insights into the different characteristics of taste enhancement of N-Suc-AAs and the impact of chemical structure on such specificity.

Gastric digestion of the sweet-tasting plant protein thaumatin releases bitter peptides that reduce H. pylori induced pro-inflammatory IL-17A release via the TAS2R16 bitter taste receptor

About half of the world's population is infected with the bacterium Helicobacter pylori. For colonization, the bacterium neutralizes the low gastric pH and recruits immune cells to the stomach. The immune cells secrete cytokines, i.e., the pro-inflammatory IL-17A, which directly or indirectly damage surface epithelial cells. Since (I) dietary proteins are known to be digested into bitter tasting peptides in the gastric lumen, and (II) bitter tasting compounds have been demonstrated to reduce the release of pro-inflammatory cytokines through functional involvement of bitter taste receptors (TAS2Rs), we hypothesized that the sweet-tasting plant protein thaumatin would be cleaved into anti-inflammatory bitter peptides during gastric digestion. Using immortalized human parietal cells (HGT-1 cells), we demonstrated a bitter taste receptor TAS2R16-dependent reduction of a H. pylori-evoked IL-17A release by up to 89.7 ± 21.9% (p ≤ 0.01). Functional involvement of TAS2R16 was demonstrated by the study of specific antagonists and siRNA knock-down experiments.

Application of multiple-intake temporal check all that apply: a case study of strawberry yoghurt formulated with alternative sweeteners

BACKGROUND

It is crucial to reduce the high sugar content of fruit yoghurts in response to the excessive weight gain epidemic. The use of alternative sweeteners in yoghurts is often associated with the negative sensory attributes that can have an impact on yoghurt liking. The main objective of this research was to investigate the effect of alternative sweeteners and strawberry puree addition on the temporal sensory profile of yoghurt using multiple-intake temporal check all that apply (TCATA). A novel approach to the statical analysis of the temporal sensory data was employed by using aligned rank transformation-analysis of variance to investigate the differences between sensory attributes within different products and within different intakes.

RESULTS

Results showed that the attributes sweet and fruity decreased when the concentration of fruit puree was increased at low concentration of sucrose. Interestingly, when the concentration of fruit puree was increased, fruitiness increased and mouthcoating decreased at low concentration of stevia. With successive intakes, the attributes sweet, sour, creamy and fruity significantly decreased in yoghurts sweetened with sucrose, xylitol and stevia. Yoghurts containing low concentrations of sucrose or xylitol and fruit puree were liked the most. However, stevia-sweetened yoghurts varying in sweetener and puree concentration were not significantly different in liking. In order to investigate the consumer acceptance of yoghurts, a novel approach was used - that is, utilizing TCATA temporal data to investigate temporal drivers of liking for each yoghurt type.

CONCLUSION

The use of multiple statistical analysis to analyse temporal data suggested that both sweetener and puree concentration need to be considered when developing products using alternative sweeteners. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Multi-attribute temporal descriptive methods in sensory analysis applied in food science: A systematic scoping review

Among descriptive sensory evaluation methods, temporal methods have a wide audience in food science because they make it possible to follow perception as close as possible to the moment when sensations are perceived. The aim of this work was to describe 30 years of research involving temporal methods by mapping the scientific literature using a systematic scoping review. Thus, 363 research articles found from a search in Scopus and Web of Science from 1991 to 2022 were included. The extracted data included information on the implementation of studies referring to the use of temporal methods (details related to subjects, products, descriptors, research design, data analysis, etc.), reasons why they were used and the conclusions they allowed to be drawn. Metadata analysis and critical appraisal were also carried out. A quantitative and qualitative synthesis of the results allowed the identification of trends in the way in which the methods were developed, refined, and disseminated. Overall, a large heterogeneity was noted in the way in which the temporal measurements were carried out and the results presented. Some critical research gaps in establishing the validity and reliability of temporal methods have also been identified. They were mostly related to the details of implementation of the methods (e.g., almost no justification for the number of consumers included in the studies, absence of report on panel repeatability) and data analysis (e.g., prevalence of use of exploratory data analysis, only 20% of studies using confirmatory analyses considering the dynamic nature of the data). These results suggest the need for general guidelines on how to implement the method, analyze and interpret data, and report the results. Thus, a template and checklist for reporting data and results were proposed to help increase the quality of future research.

Effect of texture preference on food texture perception: Exploring the role of matching food texture and preference

This study aimed to investigate the influence of smooth texture preference on smoothness perception. An online questionnaire (Study 1, n = 464) and a sensory evaluation test (Study 2, n = 65) were administered to Japanese elderly participants (65-74 years), with common Japanese confectionery (Daifuku) as test foods. Through the online questionnaire, four distinct texture preference groups were formed based on the factors of preference for smoothness and firmness of the inner bean paste layer. Analysis of the food preference scale for imbalanced diet (FPSID) revealed that smooth-texture likers were more likely to be picky eaters than firm-texture likers. Furthermore, high (HiSm) and low smoothness preference groups (LoSm) were selected for the food sensory evaluation test to compare perceived textures (smoothness and firmness). Only the HiSm group exhibited a positive association between perceived smoothness and overall texture liking, perceiving smoothness significantly more intense than the LoSm group in situations where overall texture liking was high. This finding indicates that smooth texture preference does not act independently but rather interacts with food texture matching to affect perception. Our findings suggest that when food texture aligns with individuals' preferences, it elicits hedonic emotions and dynamically enhances food texture perception. This preference-involved perceptual process may contribute to the development of more explicit texture preferences.

Exploring the textural dynamics of dairy and plant-based yoghurts: A comprehensive study

The mouthfeel and texture of dairy and non-dairy yoghurts play a critical role in food acceptance and liking. The present study aimed to understand the oral perception of commercially available dairy and non-dairy yoghurts. Four dairy and four non-dairy yoghurts with different levels of protein and fat were analyzed to understand the impact of particle size, textural properties and frictional coefficient on the dynamic sensory mouthfeel characteristics measured by the temporal dominance of sensations (TDS) method. Differences in friction coefficients of dairy and non-dairy yoghurts were observed. The friction factor was lower for high-fat dairy yoghurts than for non-dairy yoghurts. The particle size d₉₀ in yoghurts was positively related to graininess perception (r=0.81) and negatively associated with mouthfeel liking (r=-0.87) and overall liking (r=-0.80). For the TDS results, "creaminess" and "thickness" were significantly dominant for dairy yoghurts, while "melty" and "easy to dissolve" were dominant attributes for non-dairy yoghurts. Creaminess perception improves the mouthfeel liking (r=0.72) and overall liking (r=0.59) of yoghurts and is the driver of liking. The findings of this study help understand the intrinsic mouthfeel properties of commercial dairy and non-dairy yoghurts, which will provide valuable insight to product developers during the new product formulation.

Dynamic Zanthoxylum pungency characteristics and their correlation with sanshool composition and chemical structure

Huajiao (Zanthoxylum) from different regions varies in pungency features. The objective of this study was to explore the reasons for the differences. Temporal check-all-that-apply (TCATA) and time-intensity (TI)) were used to determine time-related pungency features of huajiao and sanshools. The compositions of sanshools in huajiao were measured by high-performance liquid chromatograph (HPLC). TI results revealed that hydroxy-γ-sanshool tingling and numbing duration (1332.00 ± 50.91 and 1020.00 ± 61.19 s, respectively) were about twice that of hydroxy-α-sanshool (720.00 ± 25.92 and 584.00 ± 22.63 s, respectively). Tingling and numbing were not perceived by hydroxy-β-sanshool and hydroxy-γ-isosanshool. HPLC results showed that HαSS was the main component of huajiao sanshools, representing 71.06 % to 92.90 %. TCATA results revealed the pungency sensations appearance sequence: tingling, salivating, cooling, and burning appeared first, followed by vibrating, and numbing was perceived last. These findings revealed the relationship between the compositions of sanshool and the pungency features of huajiao.

A Timely Application-Temporal methods, past, present, and future

Eating is a dynamic experience, and temporal sensory methods have been proposed to document how products change over the course of consumption or use (nonfood). A search of online databases yielded approximately 170 sources related to temporal evaluation of food products that were compiled and reviewed. This review summarizes the evolution of temporal methodologies (past), offers guidance in selecting appropriate methods (present), and provides insights into the future of temporal methodologies in the sensory space. Temporal methods have evolved to document a variety of characteristics in food products including how the intensity of a specific attribute changes over time (Time-Intensity), which specific attribute is dominant at each time during evaluation (Temporal Dominance of Sensations), which attributes are present at each time point during evaluation (Temporal Check-All-That-Apply), and many others (Temporal Order of Sensations, Attack-Evolution-Finish, and Temporal Ranking). In addition to documenting the evolution of temporal methods, this review considers the selection of an appropriate temporal method based on the objective and scope of research. When choosing a temporal method, researchers should also consider the selection of panelists to perform the temporal evaluation. Future temporal research should focus on validation of new temporal methods and explore how methods can be implemented and improved to add to the usefulness of temporal techniques for researchers.

Musical and Non-Musical Sounds Influence the Flavour Perception of Chocolate Ice Cream and Emotional Responses

Auditory cues, such as real-world sounds or music, influence how we perceive food. The main aim of the present study was to investigate the influence of negatively and positively valenced mixtures of musical and non-musical sounds on the affective states of participants and their perception of chocolate ice cream. Consuming ice cream while listening to liked music (LM) and while listening to the combination of liked music and pleasant sound (LMPS) conditions gave rise to more positive emotions than listening to just pleasant sound (PS). Consuming ice cream during the LM condition resulted in the longest duration of perceived sweetness. On the other hand, PS and LMPS conditions resulted in cocoa dominating for longer. Bitterness and roasted were dominant under the disliked music and unpleasant sound (DMUS) and DM conditions respectively. Positive emotions correlated well with the temporal sensory perception of sweetness and cocoa when consuming chocolate ice cream under the positively valenced auditory conditions. In contrast, negative emotions were associated with bitter and roasted tastes/flavours under the negatively valenced auditory conditions. The combination of pleasant music and non-musical sound conditions evoked more positive emotions than when either was presented in isolation. Taken together, the results of this study support the view that sensory attributes correlated well with emotions evoked when consuming ice cream under different auditory conditions varying in terms of their valence.

Changes in temporal sensory profile, liking, satiety, and postconsumption attributes of yogurt with natural sweeteners

Abstract

Sweetened yogurts can contain between 10 and 13% added sugar. However, studies have shown that sugar reduction or replacement can influence yogurt quality. The main objective of this research was to investigate the effects of yogurt with added natural sweeteners on temporal sensory profile, liking, satiety and postconsumption measures. Yogurt samples were prepared with iso‐sweet concentrations of sucrose (9 g/100 g of plain yogurt) using xylitol (10 g/100 g), stevia (0.15 g/100 g), and monk fruit (0.15 g/100 g). Fifty panelists evaluated the temporal sensory profile of these yogurts using multiple‐intake temporal dominance of sensations (TDS), and overall liking for each intake. In addition, satiety (hunger, thirst, and fullness) and other postconsumption attributes (healthiness, satisfaction, and purchase intent) were determined. The temporal profile of yogurt sweetened with xylitol was similar to yogurt sweetened with sucrose without any onset of negative sensory characteristics at any point in intake. Yogurt sweetened with stevia had a high dominance duration for astringency. Moreover, yogurt sweetened with monk fruit showed increased dominance of attributes bitter and astringent from the first to third intake. In terms of liking, yogurt containing xylitol was scored the highest followed by stevia and monkfruit. Sweet was a positive temporal driver of liking in yogurt sweetened with monk fruit. However, mouthcoating, sweet, and sour decreased liking in yogurt sweetened with sucrose, xylitol, and stevia respectively. In terms of perceived healthiness, satisfaction and purchase intent, yogurt sweetened with sucrose scored the highest followed by xylitol. Consumption of yogurt sweetened with xylitol, stevia, or monk fruit significantly decreased hunger compared to yogurt sweetened with sucrose.

Practical Application

The current findings will play an important role for the dairy industry in understanding how sugar replacement with natural sweeteners in yogurt can influence its sensory perception and postconsumption behavior.

Challenges of pairing chocolates and nuts: Perceptions, interactions and dynamics of contrasting chocolates with nuts

Chocolates paired with nuts are highly marketed products, however, there is a lack of scientific research and limited understanding of consumer sentiment towards the combination of these food products. The main objective of this research was to determine the consumers' response towards pairing five different chocolates (dark origin, milk, Gold, white fruity, and white vanilla) and three different nuts (hazelnut, almond, and pistachio) for the creation of pairing guidelines within Barry Callebaut's range. TimeSens© software was applied to assess the dynamic interaction of flavors through temporal dominance of sensations (TDS). It was observed that each type of chocolate presents different interactions of dominant flavors depending on the nut and its applications. Furthermore, variables such as liking, balance, and check-all-that-apply (CATA) were analyzed to create pairing guidelines related to different responses on the predominant flavor of each of the chocolates. These case studies determined that the liking of the different pairs was influenced by the dominant flavors of each of the chocolates and the balance found in the match. From the predominant flavors, it was concluded that respondents preferred chocolates with sweet and dairy attributes such as: milky, creamy, buttery. Salty and vanilla flavors also made good pairs as they accentuate the nut flavor. On the contrary, chocolates with intense bitter, roasted, cocoa, and sour flavors did not create the best combinations with the nuts, as these are contrasting or strong flavors that consumers are usually unfamiliar with when combined with nuts. To complement this study, further analysis can be developed using other types of chocolates, nuts, and applications, and then comparing the dominant flavors of the chocolates with distinctive nuts to assess the consumers' response towards the combinations.

Salt and Aroma Compound Distributions Influence Flavour Release and Temporal Perception While Eating Hot-Served Flans

To counteract the negative effect of salt overconsumption on health, strategies have been developed to reduce the salt content in food products. Among them, two promising strategies based on odour-induced saltiness enhancement and the heterogeneous distribution of flavour compounds were combined and assessed in four-layer cream-based snacks. To investigate the relationship between saltiness enhancement, temporal release and perception of flavour compounds in hot snacks with heterogeneous distribution of salt and aroma compounds, complementary techniques were used: nose space PTR-Tof-MS (Proton Transfer Reaction-Time of Flight–Mass Spectrometry) to assess the release of aroma compounds in vivo, and ATI (Alternate Time-Intensity) and TDS Temporal Dominance of Sensations) to evaluate perception as a function of time. The obtained results confirmed that the strategy of concentrating salt in the outer layer of a multilayer product was the optimal solution with respect to taste intensity. Heterogeneous salt distribution decreased aroma compound release and consequently aroma intensity but in different ways according to both salt and added aroma distribution in the food matrix. The salty taste enhancement could be due to the initial strong dominance of the salty sensation at the very beginning of the eating process. The involved mechanisms rely on a combination of physico-chemical and perceptual effects which are not clear yet.

Standardized methods for testing the quality attributes of plant-based foods: Milk and cream alternatives

The food industry is creating a diverse range of plant-based alternatives to dairy products, such as milks, creams, yogurts, and cheeses due to the increasing demand from consumers for more sustainable, healthy, and ethical products. These dairy alternatives are often designed to mimic the desirable physicochemical, functional, and sensory properties of real dairy products, such as their appearance, texture, mouthfeel, flavor, and shelf-life. At present, there is a lack of systematic testing methods to characterize the properties of plant-based dairy alternatives. The purpose of this review is to critically evaluate existing methods and recommend a series of standardized tests that could be used to quantify the properties of fluid plant-based milk alternatives (milk and cream). These methods could then be used to facilitate the design of milk alternatives with somewhat similar attributes as real dairy milk by comparing their properties under standardized conditions. Moreover, they could be used to facilitate comparison of the properties of milk alternatives developed in different laboratories.

Use of strawberry and vanilla natural flavors for sugar reduction: A dynamic sensory study with yogurt

Yogurt is a food with great acceptance by consumers. However, this product often contains excessive added sugar content. A potential strategy to reduce sugar content without compromising sensory quality is the addition of flavors. Thus, the objective of this work was to evaluate the relationship between flavors (vanilla and strawberry) and sweet taste, using a time-intensity analysis, temporal dominance of sensations (TDS) and acceptance test to verifying the viability of sugar reduction in yogurt with the addition of flavors. The results showed that 25% sugar reduction in yogurt with 0.2% vanilla flavor did not affect the sweetness, as shown in temporal profiles, and hedonic perception. The yogurt with 25% sugar reduction and 0.2% strawberry flavor proved to be as well accepted as samples with ideal concentration. Therefore, study of the flavor-taste interaction for the reformulation of foods represents an important strategy to reduce sucrose concentration, maintaining a similar temporal sweetness profile.

Sensory attributes of coated tablets: Developing a formal lexicon and sensory wheel

The patient's sensory experience when taking an oral medicine is important in the assessment of its palatability, and acceptability. The aim of this study was to develop tools useful for standardisation of sensory assessment of coated tablets: a lexicon and a sensory wheel. Two randomised, double-blind sensory assessments were performed involving 83 and 52 heathy adult volunteers and two sets of coated tablets. By adapting the principles used by food sciences, a free-text description of conventional, bitter-tasting or tasteless, coated tablets was performed. In the first assessment, volunteers described the sensory attributes of the first set of tablets. The attributes collected were then validated using a second set of tablets in a separate study with different volunteers. The appropriateness and semantics of each sensory attribute was analysed. Twenty attributes most relevant for assessment of coated tablets were selected for the lexicon and associated with explicit definitions. A collection of all attributes that could possibly be triggered by coated tablets were organised in the form of a sensory wheel. This study provides a valuable insight into the sensory experience while taking a coated tablet and presents tools which can accelerate the development of palatable medicines.

Characterizing the Dynamic Taste and Retro-Nasal Aroma Properties of Oral Nutritional Supplements Using Temporal Dominance of Sensation and Temporal Check-All-That-Apply Methods

Orally Disintegrating Tablets (ODTs) are used to restore the nutritional status of people suffering from swallowing pathologies such as dysphagia. ODTs are consumed without water intake and are easily swallowed. The main active compounds of ODTs are vitamins and minerals. These nutrients can have a bad taste or aftertaste, which can be masked by sweetening or flavoring. To ensure the effectiveness of masking strategies and to prescribe a product to patients with acceptable sensory qualities, it is essential to perform a precise and complete sensory characterization of these ODTs. Temporal dominance of sensations (TDS) and temporal check-all-that-apply (TCATA) methods were chosen to characterize the temporal sensory perceptions during the consumption of four ODTs varying in galenic forms and flavoring because of their particularly acute temporality in flavor perception. The ODTs presented common and individual sensory properties, mainly related to their galenic form and to the nature of the active ingredients. The use of a nose-clip to stop retro-nasal airflow showed that flavoring had a minimal impact on the sensory taste qualities of the ODTs. A comparison between the TDS and TCATA results indicates that these tests are capable of providing complementary information on the dynamic sensory qualities of the products studied. Although results were generally similar for both methods, TDS showed a greater number of differences in sensory taste attribute, whereas TCATA was more discriminating. These methods allowed for a better understanding of the evolution of sensory perceptions of these ODTs during their consumption, which could help to optimize masking strategies and develop new products with acceptable sensory properties.

Using Multiple Sensory Profiling Methods to Gain Insight into Temporal Perceptions of Pea Protein-Based Formulated Foods

The food industry is focused on creating plant-based foods that incorporate pea protein isolates. However, pea protein isolates are often described as having persistent beany, bitter, and astringent notes that can decrease the desirability of the resulting foods and make static sensory profiling difficult. To obtain more realistic descriptions of the sensory experiences associated with this category of products, researchers should consider using temporal methods and multi-intake methods, which allow consumers to evaluate whole food portions. This study aimed to understand better how product composition affected the sensory perception of pea protein-based beverages using three different sensory profiling methods. Particular focus was placed on beany, bitter, and astringent notes. Twelve pea protein-based beverages were formulated; they varied in pea protein type (pellet vs. isolate) and their content of gellan gum, salt, sunflower oil, sugar, and soy lecithin. They were evaluated by 16 trained panelists using three sensory profiling methods: static block profiling, mono-intake temporal dominance of sensations (TDS) profiling, and multi-intake TDS profiling. The static block and mono-intake TDS profiling methods yielded complementary results about the impact of beverage composition on attribute perceptions. Static block profiling revealed that beaniness was mainly affected by gellan gum and oil content and that bitterness and astringency were mainly affected by protein type and gellan gum content. Mono-intake TDS profiling highlighted the dynamics of beaniness and the strong persistence of astringency, and its results suggested that higher gellan gum and salt contents could limit this persistence. Multi-intake TDS profiling found that, throughout the consumption of a full product portion, beaniness and bitterness decreased, indicating an adaptation effect, while fattiness increased, indicating a build-up effect. This study has increased the understanding of how pea protein-based beverages are perceived under conditions that more closely resemble those associated with real-life consumption. It has also revealed how product formulation can reduce bitterness and astringency.

The Impact of High-Pressure Processing on Physicochemical Properties and Sensory Characteristics of Three Different Lamb Meat Cuts

This study investigated the effects of high pressure processing (HPP) on the physicochemical properties and sensory characteristics of different lamb meat cuts. Lamb meat discolouration occurred when HPP was applied at 400 and 600 MPa. Thiobarbituric acid reactive substances (TBARS) values significantly increased with pressure increase from 200 to 600 MPa for loin cut, and 300 to 600 MPa for shoulder and shank cuts. Saturated fatty acid and polyunsaturated fatty acid content significantly decreased with pressure increase from 200 to 600 MPa for shank and shoulder cuts, and 300 to 600 MPa for loin cut. Free amino acids content significantly increased in shank and loin cuts with pressure increase after 200 MPa, and in shoulder cuts after 400 MPa. In addition, samples treated with HPP at high pressure levels of 400 and 600 MPa were associated with browned, livery and oxidized flavours. The pressure levels applied and type of cuts used are important considerations during HPP processing as they influenced physicochemical and sensory properties of lamb samples.

Coffee growing altitude influences the microbiota, chemical compounds and the quality of fermented coffees

The objective of this work was to evaluate the influence of different altitudes on the epiphytic microbiota of coffee beans and on sensorial and chemical quality of coffees grown at 800, 1000, 1200, and 1400 m in Serra do Caparaó, Espírito Santo, Brazil. For microbiological analysis, the population counts of mesophilic bacteria, lactic acid bacteria (LAB), and yeasts were performed from the surface plating. The isolates were grouped and identified from the Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) and sequencing of the ribosomal region was used. The chemical composition of the green grains was evaluated by Raman spectroscopy, and the sensory analysis of the roasted grains was performed using temporal dominance of sensations (TDS). During fermentation, there was a decrease in the LAB in pulped coffee from 800 and 1000 m altitude, while an increase was observed at 1200 and 1400 m. In natural coffee, there was an increase of LAB population at all altitudes. The highest diversity of mesophilic bacteria and yeast were identified in natural 1400 m and 1000 m, respectively. However pulped coffee treatments it was at 1200 m and 800 m. The chlorogenic acid and fatty acids in the green bean changed with altitude variation and processing. The floral attribute was detected only at altitude 1400 m. Caramel, chocolate and almond attributes were most frequently detected in coffees at different altitudes and processing. Therefore, pulped coffee processing was most suitable at low altitude while at high altitudes, both processes can be conducted to obtain a beverage with unusual sensory profile.

Background soundscapes influence the perception of ice-cream as indexed by electrophysiological measures

Listening to specific soundscapes can influence multisensory flavour perception. In the present study, changes in people's perception of the flavour of ice-cream were tracked over time as they listened to a café soundscape, and when this soundscape was overlaid with either bird, machine, or forest soundscapes. In addition, emotions and electrophysiological measures were recorded in order to help understand any changes in taste/flavour perception. The results of Temporal Dominance of Sensation (TDS) analysis revealed that cocoa was dominant early in the consumption episode while listening to the control café soundscape. Sweetness and creaminess were dominant at the start of the consumption episode while listening to the café-forest soundscape. Creaminess was dominant at the start of the consumption episode while listening to the café-bird soundscape. Bitterness was perceived at the end of the consumption period while listening to the café control and café-machine soundscapes. These findings demonstrate the crossmodal influence of audition on perception in the chemical senses. As expected, negative emotions were significantly higher when listening to the machine soundscape, while positive emotions were significantly higher when listening to café-forest and café-bird soundscapes. Evaluating ice-cream while listening to the café-machine soundscape evoked negative emotions associated with bitterness and creaminess, that were also associated with increased heart rate (HR) and respiration rate (RESP). When listening to the café-forest soundscape, ice-cream was associated with sweetness, and positive emotions (e.g., love, satisfaction, happiness, amusement and enjoyment). This might have led to increased blood volume pulse (BVP) amplitude, which is itself indicative of a relaxed state. Enhancing eating experiences by means of atmospheric soundscapes that are designed specifically to accentuate specific aspects of multisensory taste/flavour perception is currently an area of interest in the food sciences literature and will likely lead to future commercial applications.

Environmental Sounds Influence the Multisensory Perception of Chocolate Gelati

Recently, it has been shown that various auditory stimuli modulate flavour perception. The present study attempts to understand the effects of environmental sounds (park, food court, fast food restaurant, cafe, and bar sounds) on the perception of chocolate gelato (specifically, sweet, bitter, milky, creamy, cocoa, roasted, and vanilla notes) using the Temporal Check-All-That-Apply (TCATA) method. Additionally, affective ratings of the auditory stimuli were obtained using the Self-Assessment Manikin (SAM) in terms of their valence, arousal, and dominance. In total, 58 panellists rated the sounds and chocolate gelato in a sensory laboratory. The results revealed that bitterness, roasted, and cocoa notes were more evident when the bar, fast food, and food court sounds were played. Meanwhile, sweetness was cited more in the early mastication period when listening to park and café sounds. The park sound was significantly higher in valence, while the bar sound was significantly higher in arousal. Dominance was significantly higher for the fast food restaurant, food court, and bar sound conditions. Intriguingly, the valence evoked by the pleasant park sound was positively correlated with the sweetness of the gelato. Meanwhile, the arousal associated with bar sounds was positively correlated with bitterness, roasted, and cocoa attributes. Taken together, these results clearly demonstrate that people's perception of the flavour of gelato varied with the different real-world sounds used in this study.

Did assessors select attributes by chance alone in your TDS study, and how relevant is it to know?

Dominance rates arising from Temporal Dominance of Sensations (TDS) data are almost always plotted and understood with reference to chance and significance lines, which are based on the assumption of random attribute selection. These lines are auxiliary to the chart, and used to interpret the dominance rates; when the dominance rate for some attribute exceeds the significance line, the conventional interpretation is that this attribute is being noticed significantly. Thus, these auxiliary lines are used to provide a convenient, qualitative interpretation of TDS data. However, the concept of the significance lines has some deficiencies that we explore in this paper. We were interested in what real TDS data look like under a true null hypothesis of random attribute selection. To obtain such data, we sampled from real TDS data (keeping products and assessors' selection patterns intact) to create dominance rates based on random attribute selections. Dominance rates exceed the significance line about 5% of the time (across attributes and time points), as expected. These curves differed from any real TDS curves that we have ever observed previously insofar as that they were unusually flattened. Next, we sampled again from real TDS data (keeping attributes and assessors' selection patterns intact) to create dominance rates based on attribute selections for random (hybrid) products. Derived TDS curves much more closely resemble curves from real TDS studies and show a lot of "significances", even though products are artificially created by the permutations. This is due to properties of the products that are inherent to the product category: e.g., hard will occur early during the evaluation of a chocolate (if at all), but not towards the end. From these simulations, we reach two conclusions. First, we recognize that the hypothesis that assessors select the dominant attribute completely at random is almost always false. Second, the reason that it is false is that, regardless of the product, there is a time-dependent category signature present, as well as competition between attributes, such that significances for one attribute depend on which other attributes are on the list. These properties limit the informative value of the conventional TDS significance lines that are widely used. As an alternative, we explore the possibility of context-dependent significance thresholds which are customized for and aligned with research objectives. These reference lines are recommended for improved interpretation of data arising from TDS studies.

A Comparison of Temporal Dominance of Sensation (TDS) and Quantitative Descriptive Analysis (QDA™) to Identify Flavors in Strawberries

Temporal dominance of sensations (TDS) is a rapid descriptive method that offers a different magnitude of information to traditional descriptive analysis methodologies. This methodology considers the dynamic nature of eating, assessing sensory perception of foods as they change throughout the eating event. Limited research has applied the TDS methodology to strawberries and subsequently validated the results against Quantitative Descriptive Analysis (QDA™). The aim of this research is to compare the TDS methodology using an untrained consumer panel to the results obtained via QDA™ with a trained sensory panel. The trained panelists (n = 12, minimum 60 hr each panelist) were provided with six strawberry samples (three cultivars at two maturation levels) and applied QDA™ techniques to profile each strawberry sample. Untrained consumers (n = 103) were provided with six strawberry samples (three cultivars at two maturation levels) and required to use TDS methodology to assess the dominant sensations for each sample as they change over time. Results revealed moderately comparable product configurations produced via TDS in comparison to QDA™ (RV coefficient = 0.559), as well as similar application of the sweet attribute (correlation coefficient of 0.895 at first bite). The TDS methodology however was not in agreement with the QDA™ methodology regarding more complex flavor terms. These findings support the notion that the lack of training on the definition of terms, together with the limitations of the methodology to ignore all attributes other than those dominant, provide a different magnitude of information than the QDA™ methodology.

PRACTICAL APPLICATION

A comparison of TDS to traditional descriptive analysis indicate that TDS provides additional information to QDA™ regarding the lingering component of eating. The QDA™ results however provide more precise detail regarding singular attributes. Therefore, the TDS methodology has an application in industry when it is important to understand the lingering profile of products. However, this methodology should not be employed as a replacement to traditional descriptive analysis methods.

Can we monitor adaptation of juvenile goats to a new social environment through continuous qualitative behaviour assessment?

We aimed to verify whether Continuous Qualitative Behaviour Assessment (10 observers used a list of six qualitative descriptors) paired with Temporal Dominant Behavioural Expression (the same observers were asked to select the dominant descriptor and to score its intensity level) was able to monitor fluctuations of animal behaviour expression over time. We applied these techniques to three groups of juvenile goats either weaned (group C), or un-weaned (groups WOM and WM). Each animal was separated from its group, moved to group C and tested for 30 min either while their mothers were at pasture, or while their mothers were in an adjacent pen (group WOM and WM, respectively). Animals from group C were separated from their group and immediately reintroduced to it. TDBE duration and score of each descriptor of behavioural expression were able to detect differences among groups but were unable to describe how the behaviour of the goats changed as the time progressed. TDBE curves described the evolution of each behavioural expression of each animal over time but were unable to detect differences among groups. The χ2 test conducted on peaks of dominance, albeit displaying the variations of the behavioural expression over time and allowing the assessment of differences among groups, focussed on occurrences of higher agreement between observers while neglecting most of the information concerning the descriptors above the level of significance. Conversely, based on mixed analysis of variance with the fixed effects of group, test interval and group x test interval (animal nested into group and observer were considered to be random), most of the descriptors were able to discriminate the three experimental groups while preserving the information on the fluctuations of the behavioural expression of the animals during the test.