Physiological Responses to Basic Tastes for Sensory Evaluation of Chocolate Using Biometric Techniques

Wearable sensors to measure the influence of sonic seasoning on wine consumers in a live context: a preliminary proof-of-concept study

BACKGROUND

Any action capable of creating expectations about product quality would be able to modulate experienced pleasantness. In this context, during the 2022 edition of the Internet Festival (Pisa, Italy) a 'social experiment' was promoted to set up an affordable and reliable methodology based on wearable sensors to measure the emotions aroused in a live context on consumers by different kinds of wines. Therefore, five wines (two faulty ones and three high-quality samples) were proposed to 50 non-selected consumers in an arousing context with live jazz music as background. Both explicit (questionnaires) and two different approaches for implicit methods (electrocardiogram (ECG) recorded by wearable sensors vs. smartphones), the latter performed on a subgroup of 16, to measure the emotions aroused by wines and music were utilized synergistically.

RESULTS

According to our findings: (i) wine undoubtedly generates a significant emotional response on consumers; (ii) this answer is multifaceted and attributable to the quality level of the wine tasted. In fact, all things being equal, while drinking wine even untrained consumers can perfectly recognize good wines compared to products of lower quality; (iii) high-quality wines are able to induce a spectrum of positive emotions, as observed by the analysis of ECG signals, especially when they are coupled with background music.

CONCLUSION

The framework has certainly played to the advantage of good-quality wines, fostering their positive emotional characteristics on the palate even of some less experienced consumers, thanks to a dragging effect towards a positive mood generated by the surrounding conditions (good music in a beautiful location). © 2024 Society of Chemical Industry.

Assessing the influence of spontaneous fermentation on consumer emotional responses to roasted arabica coffee in a biometric approach

Beyond sensory quality, food-evoked emotions play a crucial role in consumers acceptance and willingness to try, which are essential for product development. The link between fermented coffee sensory characteristics and elicited emotional responses from consumers is underexplored. This study aimed to evaluate consumers' acceptability of spontaneously fermented and unfermented roasted coffee through self-reported sensory evaluation and biometrics assessment. Self-reported liking in 15-cm non-structured scale, multiple choice of negative, neutral, and positive emojis, and subconscious emotional responses from 85 regular coffee consumers were analysed. Their relationship with the pattern of volatile aromatic compounds were also investigated. Fermented (F) and unfermented (UF) coffee beans with light- (L), dark- (D), and commercial dark (C) roasting levels were brewed and evaluated along with gas chromatography-mass spectrometry measurement. Multivariate data analysis was conducted to explore the inner relationships among volatile compounds, self-reported liking, and biometrics. Unfermented-dark roasted coffee (UFD) had highest overall consumer liking response ± standard error (8.68 ± 0.40), followed by the fermented-dark roasted (FD) at 7.73 ± 0.43 with no significant differences (p > 0.05). Fermented light-roasted coffee was associated with lower liking scores and negative emotional responses. In contrast, dark roasted coffee, which was linked to positive emojis and emotional responses, exhibited less detected peak area of volatile compounds contributing fruity and vegetative aromas, such as benzaldehyde, furfuryl acetate, 2-acetyl-1-methyl pyrrole, and isovaleric acid, potentially as negative drivers of consumer liking. Findings from this study could guide coffee manufacturers in developing specialty coffee if spontaneous fermentation is offered.

One of the major challenges of masking the bitter taste in medications: an overview of quantitative methods for bitterness

Objective

The aim of the present study was to carry out a systematic research on bitterness quantification to provide a reference for scholars and pharmaceutical developers to carry out drug taste masking research. Significance: The bitterness of medications poses a significant concern for clinicians and patients. Scientifically measuring the intensity of drug bitterness is pivotal for enhancing drug palatability and broadening their clinical utility.

Methods

The current study was carried out by conducting a systematic literature review that identified relevant papers from indexed databases. Numerous studies and research are cited and quoted in this article to summarize the features, strengths, and applicability of quantitative bitterness assessment methods.

Results

In our research, we systematically outlined the classification and key advancements in quantitative research methods for assessing drug bitterness, including in vivo quantification techniques such as traditional human taste panel methods, as well as in vitro quantification methods such as electronic tongue analysis. It focused on the quantitative methods and difficulties of bitterness of natural drugs with complex system characteristics and their difficulties in quantification, and proposes possible future research directions.

Conclusion

The quantitative methods of bitterness were summarized, which laid an important foundation for the construction of a comprehensive bitterness quantification standard system and the formulation of accurate, efficient and rich taste masking strategies.

An advance in novel intelligent sensory technologies: From an implicit-tracking perspective of food perception

Food sensory evaluation mainly includes explicit and implicit measurement methods. Implicit measures of consumer perception are gaining significant attention in food sensory and consumer science as they provide effective, subconscious, objective analysis. A wide range of advanced technologies are now available for analyzing physiological and psychological responses, including facial analysis technology, neuroimaging technology, autonomic nervous system technology, and behavioral pattern measurement. However, researchers in the food field often lack systematic knowledge of these multidisciplinary technologies and struggle with interpreting their results. In order to bridge this gap, this review systematically describes the principles and highlights the applications in food sensory and consumer science of facial analysis technologies such as eye tracking, facial electromyography, and automatic facial expression analysis, as well as neuroimaging technologies like electroencephalography, magnetoencephalography, functional magnetic resonance imaging, and functional near-infrared spectroscopy. Furthermore, we critically compare and discuss these advanced implicit techniques in the context of food sensory research and then accordingly propose prospects. Ultimately, we conclude that implicit measures should be complemented by traditional explicit measures to capture responses beyond preference. Facial analysis technologies offer a more objective reflection of sensory perception and attitudes toward food, whereas neuroimaging techniques provide valuable insight into the implicit physiological responses during food consumption. To enhance the interpretability and generalizability of implicit measurement results, further sensory studies are needed. Looking ahead, the combination of different methodological techniques in real-life situations holds promise for consumer sensory science in the field of food research.

Emotional response to healthier foods: Influence of culture and health consciousness

Sugar, salt, and fat content in processed products are important concerns for consumers. Hence, alternative "healthy" versions of conventional foods such as chocolate, potato chips, and yogurt are offered. This work aimed to define the emotional response of consumers from different cultural backgrounds (Spain vs. Brazil) evoked by healthier versions of conventional products and the relationship between hedonic responses and health consciousness. A total of 186 Brazilian and 152 Spanish consumers participated in this online cross-cultural study. Participants answered a Health Consciousness Questionnaire and an emotional check-all-that-applies questionnaire using picture stimuli of conventional chocolate, potato chips, and yogurt and their healthier versions with less sugar, salt, and fat content, respectively. The Brazilians' emotional responses were more diverse for all stimuli compared to the Spaniards'. However, participants from both cultures rated an average of "slightly agree" on the health consciousness scale; a higher level of consumption, liking, and willingness to buy; and a higher frequency of positive emotional terms for the stimuli of conventional products compared to their healthier versions. A higher frequency of evocation of "active" is strongly associated with higher levels of health consciousness. Strategic actions by the food industry and government must consider cultural, emotional, and health-conscious factors to encourage the consumption of healthier foods. PRACTICAL APPLICATION: Food manufacturers can use the information obtained from this study to create healthier versions of their products that appeal to consumers' emotional responses and health consciousness levels. The findings can assist in designing strategic actions to promote healthier food consumption by emphasizing the benefits of healthier food choices and making them more appealing to consumers. The methodology employed in this study can also be applied to further studies aimed to assess emotional responses to food stimuli across different cultures.

Insights into brain perceptions of the different taste qualities and hedonic valence of food via scalp electroencephalogram

Investigating brain activity is essential for exploring taste-experience related cues. The paper aimed to explore implicit (unconscious) emotional or physiological responses related to taste experiences using scalp electroencephalogram (EEG). We performed implicit measures of tastants of differing perceptual types (bitter, salty, sour and sweet) and intensities (low, medium, and high). The results showed that subjects were partially sensitive to different sensory intensities, i.e., for high intensities, taste stimuli could induce activation of different rhythm signals in the brain, with α and θ bands possibly being more sensitive to different taste types. Furthermore, the neural representations and corresponding sensory qualities (e.g., "sweet: pleasant" or "bitter: unpleasant") of different tastes could be discriminated at 250-1,500 ms after stimulus onset, and different tastes exhibited distinct temporal dynamic differences. Source localization indicated that different taste types activate brain areas associated with emotional eating, reward processing, and motivated tendencies, etc. Overall, our findings reveal a larger sophisticated taste map that accounted for the diversity of taste types in the human brain and assesses the emotion, reward, and motivated behavior represented by different tastes. This study provided basic insights and a perceptual foundation for the relationship between taste experience-related decisions and the prediction of brain activity.

Sensory and affective response to chocolate differing in cocoa content: A TDS and facial electromyography approach

Existing research has offered insight into facial activities and their associations with hedonic liking during the consumption of basic food samples and suggests facial changes during consumption are linked to the hedonic evaluation of tastes and, thus related to the taster's perception rather than the tastes themselves. This study tests whether, during the consumption of commercially available dark chocolate, a complex food product, which can be high in bitterness but expectedly so, how facial activities are linked to the bitterness levels and the hedonic liking of the samples. To do this we carried out two studies with untrained consumers, the first of which captured temporally dynamic sensory perception during the consumption of dark chocolate samples of 36% and 85% cocoa content, using the Temporal Dominance of Sensations (TDS) approach. The second study captured facial EMG over the corrugator and zygomaticus muscles during the consumption of dark chocolate samples (36%, 70%, and 85% cocoa). Specifically, the aim of this research was to investigate whether corrugator activity had a greater association with bitterness perception, linked to cocoa, or hedonic evaluation. Capturing the dynamic sensory profile of chocolate samples allowed an investigation into the time points most evident of sensory variation related to the bitterness and sweetness of the taste, allowing insight into whether facial activities also deviated during this time. These data offer evidence to suggest that corrugator was associated with hedonic evaluation during consumption of the samples, with the most liked samples (being those with 70% and 36% cocoa) eliciting similar corrugator activities and less activity than the least liked 85% cocoa content sample; however, there was also evidence to suggest a significant variation in participants' corrugator activity during the period of oral processing when bitterness was most evident in the 85% cocoa sample and sweetness was most evident in the 36% cocoa sample (i.e., the time when bitterness and sweetness were most divergent) Further investigation showed a variation in facial activities elicited during consumption of the 36% cocoa sample based on whether individuals were part of the group who favoured the 85% cocoa sample or the group favouring the 36% cocoa sample. The findings, therefore, suggest facial EMG, specifically over the corrugator, appears to be related to the hedonic evaluation of a complex food product and not the taste itself. Furthermore, being aware of the time points where sensory variations are most apparent between samples can allow for targeted investigation into facial EMG and its ability to distinguish food samples.

The Application of Biometric Approaches in Agri-Food Marketing: A Systematic Literature Review

A challenge in social marketing studies is the cognitive biases in consumers' conscious and self-reported responses. To help address this concern, biometric techniques have been developed to obtain data from consumers' implicit and non-verbal responses. A systematic literature review was conducted to explore biometric applications' role in agri-food marketing to provide an integrated overview of this topic. A total of 55 original research articles and four review articles were identified, classified, and reviewed. It was found that there is a steady growth in the number of studies applying biometric approaches, with eye-tracking being the dominant method used to investigate consumers' perceptions in the last decade. Most of the studies reviewed were conducted in Europe or the USA. Other biometric techniques used included facial expressions, heart rate, body temperature, and skin conductance. A wide range of scenarios concerning consumers' purchase and consumption behaviour for agri-food products have been investigated using biometric-based techniques, indicating their broad applicability. Our findings suggest that biometric techniques are expanding for researchers in agri-food marketing, benefiting both academia and industry.

Recent Advances in Bitterness-Sensing Systems

Bitterness is one of the basic tastes, and sensing bitterness plays a significant role in mammals recognizing toxic substances. The bitter taste of food and oral medicines may decrease consumer compliance. As a result, many efforts have been made to mask or decrease the bitterness in food and oral pharmaceutical products. The detection of bitterness is critical to evaluate how successful the taste-masking technology is, and many novel taste-sensing systems have been developed on the basis of various interaction mechanisms. In this review, we summarize the progress of bitterness response mechanisms and the development of novel sensors in detecting bitterness ranging from commercial electronic devices based on modified electrodes to micro-type sensors functionalized with taste cells, polymeric membranes, and other materials in the last two decades. The challenges and potential solutions to improve the taste sensor quality are also discussed.

Digital technologies to assess yoghurt quality traits and consumers acceptability

BACKGROUND

Sensory biometrics provide advantages for consumer tasting by quantifying physiological changes and the emotional response from participants, removing variability associated with self-reported responses. The present study aimed to measure consumers' emotional and physiological responses towards different commercial yoghurts, including dairy and plant-based yoghurts. The physiochemical properties of these products were also measured and linked with consumer responses.

RESULTS

Six samples (Control, Coconut, Soy, Berry, Cookies and Drinkable) were evaluated for overall liking by n = 62 consumers using a nine-point hedonic scale. Videos from participants were recorded using the Bio-Sensory application during tasting to assess emotions and heart rate. Physicochemical parameters Brix, pH, density, color (L, a and b), firmness and near-infrared (NIR) spectroscopy were also measured. Principal component analysis and a correlation matrix were used to assess relationships between the measured parameters. Heart rate was positively related to firmness, yaw head movement and overall liking, which were further associated with the Cookies sample. Two machine learning regression models were developed using (i) NIR absorbance values as inputs to predict the physicochemical parameters (Model 1) and (ii) the outputs from Model 1 as inputs to predict consumers overall liking (Model 2). Both models presented very high accuracy (Model 1: R = 0.98; Model 2: R = 0.99).

CONCLUSION

The presented methods were shown to be highly accurate and reliable with respect to their potential use by the industry to assess yoghurt quality traits and acceptability. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

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.

Neuroorganoleptics: Organoleptic Testing Based on Psychophysiological Sensing

There is an increasing interest, in consumer behaviour research related to food and beverage, in taking a step further from the traditional self-report questionnaires and organoleptic properties assessment. With the growing availability of psychophysiological data acquisition devices, and advancements in the study of the underlying signal sources seeking affective state assessment, the use of psychophysiological data analysis is a natural evolution in organoleptic testing. In this paper we propose a protocol for what can be defined as neuroorganoleptic analysis, a method that combines traditional approaches with psychophysiological data acquired during sensory testing. Our protocol was applied to a case study project named MobFood, where four samples of food were tested by a total of 83 participants, using preference and acceptance tasks, across three different sessions. Best practices and lessons learned regarding the laboratory setting and the acquisition of psychophysiological data were derived from this case study, which are herein described. Preliminary results show that certain Heart Rate Variability (HRV) features have a strong correlation with the preferences self-reported by the participants.

Taste Responses to Chocolate Pudding with Different Sucrose Concentrations through Physiological and Explicit Self-Reported Measures

The past few decades have seen significant methodological and theoretical change within sensory science, including in food sciences. The physiological reaction to the Autonomous Nervous System (ANS) provides insightful information in interpreting consumers’ sensory and affective reactions. In this regard, we investigated how explicit responses of liking and perceived intensity of sensory features (sweet, bitter, and astringency) and implicit objective physiological responses of Heart Rate (HR) and Galvanic Skin Response (GSR) are modulated when varying the sweetness (sucrose concentration with 38; 83; 119; 233 g/kg) level in a cocoa-based product (dark chocolate pudding) and their relationship. The demographic effects on responses were also investigated. Results showed the effects of the sucrose concentration levels on liking and perceived intensity of all the sensory characteristics and on HR responses, which highlighted a significant effect of the sucrose concentration level. As regards the relationship between variables, a significant positive effect was found for the sucrose concentration level 3, where an increase in HR leads to an increase in liking; for the perceived bitterness, a significant positive effect of HR for the sucrose concentration level 1; and for the perceived astringent, a significant positive effect of HR for the sucrose concentration level 2. While we found no significant main effect of gender on our dependent variables, the results highlight a significant main effect of age, increasing the adult population responses. The present research helps to understand better the relationship between explicit and implicit sensory study variables with foods. Furthermore, it has managerial applications for chocolate product developers. The level of sweetness that might be optimal to satisfy at the explicit level (liking) and the implicit level (HR or emotional valence) is identified.

Differences in Hedonic Responses, Facial Expressions and Self-Reported Emotions of Consumers Using Commercial Yogurts: A Cross-Cultural Study

Hedonic scale testing is a well-accepted methodology for assessing consumer perceptions but is compromised by variation in voluntary responses between cultures. Check-all-that-apply (CATA) methods using emotion terms or emojis and facial expression recognition (FER) are emerging as more powerful tools for consumer sensory testing as they may offer improved assessment of voluntary and involuntary responses, respectively. Therefore, this experiment compared traditional hedonic scale responses for overall liking to (1) CATA emotions, (2) CATA emojis and (3) FER. The experiment measured voluntary and involuntary responses from 62 participants of Asian (53%) versus Western (47%) origin, who consumed six divergent yogurt formulations (Greek, drinkable, soy, coconut, berry, cookies). The hedonic scales could discriminate between yogurt formulations but could not distinguish between responses across the cultural groups. Aversive responses to formulations were the easiest to characterize for all methods; the hedonic scale was the only method that could not characterize differences in cultural preferences, with CATA emojis displaying the highest level of discrimination. In conclusion, CATA methods, particularly the use of emojis, showed improved characterization of cross-cultural preferences of yogurt formulations compared to hedonic scales and FER.

The Effect of Yellow Tea Leaves Camellia sinensis on the Quality of Stored Chocolate Confectionery

Chocolate and tea leaves are considered the most valuable sources of highly bioactive polyphenols due to their potential anti-cancer properties and beneficial effects on the cardiovascular and nervous systems. The objective of the present study was the development of a sensory profiling modality that is correlated with the taste of the chocolate enriched with yellow tea phytochemicals. The additive concentration was optimized in white chocolate and the designed product was evaluated using the sensory profiling method. It was shown that the yellow tea extract in chocolate had a significant effect on the taste and color of the product. Addition of 2.0% yellow tea powdered extract increased the value of color acceptance and caused an intensification of the aromas, particularly the leafy taste, compared to the control samples. The next step of the study was to determine the influence of tea addition in white, milk and dark chocolate subjected to 6 months of storage. The designed chocolates were tested for their activity as antioxidants (DPPH, ABTS and ORAC assay) and cholinesterase inhibitors (AChE, BChE assay). It was confirmed that the yellow tea addition affected the activity of prepared chocolates with respect to radical scavenging activity and was highest for dark chocolate with yellow tea where the values were as follows: 4373 mg Tx/100 g (DPPH), 386 mg Tx/100 g (ABTS) and 4363 µM Tx/100 g (ORAC). An increase in the anti-radical activity of chocolate with yellow tea was found after 3 months of storage, but the subsequent 3 months of storage resulted in its reduction. AChE values ranged from 0.118 to 0.730 [µM eserine/g dw] and from 0.095 to 0.480 [µM eserine/g dw] for BChE assay. Total capacity to inhibit AChE and BChE differed depending on the type of chocolate and was negatively influenced by the half-year storage. Summarizing tested values for individual samples were higher, with increasing content of cocoa liquor and yellow tea extract in the product. The results of the research show that the use of yellow tea in confectionery is promising and may appoint a new direction in functional foods.

Cross-cultural emotional response to food stimuli: Influence of consumption context

Emotional responses elicited by certain types of food can be influenced by past experiences, frequency of consumption, culture, and other personal preferences. The present research aimed i) to investigate the impact of culture (Brazilian and Spaniard) on consumers' emotional responses and acceptability of different food stimuli, and ii) to explore the influence of evoked contexts. Brazilian (n = 437) and Spanish (n = 397) participants were exposed to three visual food stimuli (image of chocolate, potato chips, and yogurt) in an online survey and reported their emotional responses. Sociodemographic data, liking, and frequency of consumption were also collected. The evoked context in our study were designed and proposed, for each product and culture, based on four dimensions (consumption time, location, social setting, and hungry state). The evoked emotional lexicon was different for each food stimulus and was clearly influenced by the cultural factor. However, there are more similarities between cultures when evaluating the same product category. The evoked contexts were appropriated and influenced the citing frequency of some emotion terms, including positive ones. The most cited emotion terms tended to positively impact product liking ratings, acting as drivers of liking. Consumption level was positively related to liking regardless of cultural interactions for both chocolate and potato chips stimuli. In conclusion, the cultural background demonstrated to be an important impact factor to be considered for understanding the effects of product, consumption occasions, and degree of liking, on emotional responses to foods. These findings offer new possibilities to be explored in marketing messages for interventions or stimuli that guide food choices.

Silicon supplementation improves the nutritional and sensory characteristics of lentil seeds obtained from drought-stressed plants

BACKGROUND

Lentil is an important nutritionally rich pulse crop in the world. Despite having a prominent role in human health and nutrition, it is very unfortunate that global lentil production is adversely limited by drought stress, causing a huge decline in yield and productivity. Drought stress can also affect the nutritional profile of seeds. Silicon (Si) is an essential element for plants and a general component of the human diet found mainly in plant-based foods. This study investigated the effects of Si on nutritional and sensory properties of seeds obtained from lentil plants grown in an Si-supplied drought-stressed environment.

RESULTS

Significant enhancements in the concentration of nutrients (protein, carbohydrate, dietary fibre, Si) and antioxidants (ascorbate, phenol, flavonoids, total antioxidants) were found in seeds. Significant reductions in antinutrients (trypsin inhibitor, phytic acid, tannin) were also recorded. A novel sensory analysis was implemented in this study to evaluate the unconscious and conscious responses of consumers. Biometrics were integrated with a traditional sensory questionnaire to gather consumers responses. Significant positive correlations (R = 0.6-1) were observed between sensory responses and nutritional properties of seeds. Seeds from Si-treated drought-stressed plants showed higher acceptability scores among consumers.

CONCLUSION

The results demonstrated that Si supplementation can improve the nutritional and sensory properties of seeds. This study offers an innovative approach in sensory analysis coupled with biometrics to accurately assess a consumer's preference towards tested samples. In the future, the results of this study will help in making a predictive model for sensory traits and nutritional components in seeds using machine-learning modelling techniques. © 2020 Society of Chemical Industry.

Sensory Analysis and Consumer Research in New Meat Products Development

This review summarises the main sensory methods (traditional techniques and the most recent ones) together with consumer research as a key part in the development of new products, particularly meat products. Different types of sensory analyses (analytical and affective), from conventional methods (Quantitative Descriptive Analysis) to new rapid sensory techniques (Check All That Apply, Napping, Flash Profile, Temporal Dominance of Sensations, etc.) have been used as crucial techniques in new product development to assess the quality and marketable feasibility of the novel products. Moreover, an important part of these new developments is analysing consumer attitudes, behaviours, and emotions, in order to understand the complex consumer–product interaction. In addition to implicit and explicit methodologies to measure consumers’ emotions, the analysis of physiological responses can also provide information of the emotional state a food product can generate. Virtual reality is being used as an instrument to take sensory analysis out of traditional booths and configure conditions that are more realistic. This review will help to better understand these techniques and to facilitate the choice of the most appropriate at the time of its application at the different stages of the new product development, particularly on meat products.

Sensory Features, Liking and Emotions of Consumers towards Classical, Molecular and Note by Note Foods

Modern cuisine served at top-end restaurants attempts to attract customers, who increasingly demand new flavor, pleasure and fun. The materials were six dishes prepared using lemon or tomatoes and made in the traditional (classical), molecular and Note by Note (NbN) versions. The study explores sensory characteristics, consumer liking of key attributes, their declared sensations and emotions, as well as consumers’ facial expressions responding to the dishes. These objectives were investigated by descriptive quantitative analysis and consumer tests. Tests included a 9-point hedonic scale for degree of liking a dish, Check-All-That-Apply (CATA) for declared sensations and FaceReader for facial expressions. The influence of factors associated with consumer attitudes toward new food and willingness to try the dishes in the future were also determined. It was stated that the product profiles represent different sensory characteristics due to the technology of food production and the ingredients used. The food neophobia and consumer innovativeness had a significant (p ≤ 0.05) effect on liking. The odor-, flavor-, texture- and overall-liking of the NbN dishes were lower than that of traditional versions but did not vary from scores for molecular samples. The expected liking of NbN dishes was higher than experienced-liking. Traditional and modern products differed in CATA terms. Classical dishes were perceived by consumers as more tasty, traditional and typical while modern cuisine dishes were perceived as more surprising, intriguing, innovative and trendy. Mimic expressions assessment by FaceReader showed similar trends in some emotions in both classical dishes and separate temporal patterns in modern products.

The Effects of Ethnically Congruent Music on Eye Movements and Food Choice-A Cross-Cultural Comparison between Danish and Chinese Consumers

Musical fit refers to the congruence between music and attributes of a food or product in context, which can prime consumer behavior through semantic networks in memory. The vast majority of research on this topic dealing with musical fit in a cultural context has thus far been limited to monocultural groups in field studies, where uncontrolled confounds can potentially influence the study outcome. To overcome these limitations, and in order to explore the effects of ethnically congruent music on visual attention and food choice across cultures, the present study recruited 199 participants from China (n = 98) and Denmark (n = 101) for an in-laboratory food choice paradigm with eye-tracking data collection. For each culture group, the study used a between-subject design with half of the participants listening to only instrumental "Eastern" music and the other half only listening to instrumental "Western" music, while both groups engaged in a food choice task involving "Eastern" and "Western" food. Chi-square tests revealed a clear ethnic congruency effect between music and food choice across culture, whereby Eastern (vs. Western) food was chosen more during the Eastern music condition, and Western (vs. Eastern) food was chosen more in the Western music condition. Furthermore, results from a generalized linear mixed model suggested that Chinese participants fixated more on Western (vs. Eastern) food when Western music was played, whereas Danish participants fixated more on Eastern (vs. Western) food when Eastern music was played. Interestingly, no such priming effects were found when participants listened to music from their own culture, suggesting that music-evoked visual attention may be culturally dependent. Collectively, our findings demonstrate that ambient music can have a significant impact on consumers' explicit and implicit behaviors, while at the same time highlighting the importance of culture-specific sensory marketing applications in the global food industry.

Non-invasive Biometrics and Machine Learning Modeling to Obtain Sensory and Emotional Responses from Panelists during Entomophagy

Insect-based food products offer a more sustainable and environmentally friendly source of protein compared to plant and animal proteins. Entomophagy is less familiar for Non-Asian cultural backgrounds and is associated with emotions such as disgust and anger, which is the basis of neophobia towards these products. Tradicional sensory evaluation may offer some insights about the liking, visual, aroma, and tasting appreciation, and purchase intention of insect-based food products. However, more robust methods are required to assess these complex interactions with the emotional and subconscious responses related to cultural background. This study focused on the sensory and biometric responses of consumers towards insect-based food snacks and machine learning modeling. Results showed higher liking and emotional responses for those samples containing insects as ingredients (not visible) and with no insects. A lower liking and negative emotional responses were related to samples showing the insects. Artificial neural network models to assess liking based on biometric responses showed high accuracy for different cultures (>92%). A general model for all cultures with an 89% accuracy was also achieved.

A Multisensor Data Fusion Approach for Predicting Consumer Acceptance of Food Products

Sensory experiences play an important role in consumer response, purchase decision, and fidelity towards food products. Consumer studies when launching new food products must incorporate physiological response assessment to be more precise and, thus, increase their chances of success in the market. This paper introduces a novel sensory analysis system that incorporates facial emotion recognition (FER), galvanic skin response (GSR), and cardiac pulse to determine consumer acceptance of food samples. Taste and smell experiments were conducted with 120 participants recording facial images, biometric signals, and reported liking when trying a set of pleasant and unpleasant flavors and odors. Data fusion and analysis by machine learning models allow predicting the acceptance elicited by the samples. Results confirm that FER alone is not sufficient to determine consumers' acceptance. However, when combined with GSR and, to a lesser extent, with pulse signals, acceptance prediction can be improved. This research targets predicting consumer's acceptance without the continuous use of liking scores. In addition, the findings of this work may be used to explore the relationships between facial expressions and physiological reactions for non-rational decision-making when interacting with new food products.

Assessing the Influence of Visual-Taste Congruency on Perceived Sweetness and Product Liking in Immersive VR

This study was designed to assess whether the combined effect of taste-congruent and incongruent extrinsic visual cues presented in virtual reality (VR) influences the perception of sweetness and product liking. Three VR environments (sweet-congruent, sweet-incongruent, and neutral) were created based on the evidence in existing literature. Participants tasted the same beverage in three VR environments and evaluated the environment and beverage liking, as well as perceived taste intensity (sweetness, sourness, and bitterness), congruency, comfort, and environment vividness. Frontal EEG alpha asymmetry (FAA) was also recorded as a complementary physiological measurement of overall liking. The results showed that the perceived sweetness of the beverage was significantly elevated in a sweet-congruent environment versus the other environments. Visual-taste congruency did not seem to have an effect on beverage liking and overall liking, whereas an increase in environment liking was found in the incongruent environment versus the other environments. These findings confirmed the significant influence of taste-specific visual cues on flavour perception, while the successful use of VR in the study provided insight into future applications of taste-specific VR environment in the modulation of flavour perception and sugar reduction.