The multisensory perception of flavor

Identification of characteristic flavor quality of ceramic-pot sealed meat after reheating based on HS-GC-IMS, bionic sensory combined chemometrics

This study investigated the impacts of microwave reheating (MR), boil reheating (BR), and steam reheating (SR) on the flavor profile of Ceramic-Pot Sealed Meat (CPSM). Electronic nose and tongue revealed that the microwaving was superior in preserving the original olfactory and gustatory profiles of CPSM compared to the other methods. Headspace- Gas chromatography- ion mobility spectrometry (HS-GC-IMS) detected 48 compounds, encompassing 15 alcohols, 11 aldehydes, 9 ketones, 7 esters, 2 alkenes, and 2 others, 1 acid. Spectral and clustering analysis revealed a significant rise in the content of Warmed-over flavor compounds after boil reheating, culminating in pronounced flavor distortion and a decline in sensory scores. Relative odor activity value (ROAV) and chemometrics identified nine substances as the principal flavor compounds responsible to flavor distortion. In conclusion, all reheating methods induce changes in the original flavor characteristics profiles of CPSM. However, microwave reheating offers superior preservation of the flavor characteristics of CPSM.

Comprehensive investigation of coffee acidity on eight different brewing methods through chemical analyses, sensory evaluation and statistical elaboration

Even if the acids composition and their role in coffee still need to be clarified, acidity is one of the main sought-after features in coffee and it is becoming one of the main quality markers. Hence, the aim of this paper was to evaluate the main parameters influencing coffee acidity with a focus on carboxylic acids. To the best of our knowledge, this is the first study regarding filter coffee prepared from specialty and mainstream coffee, differently roasted and through eight diverse extraction methods. Coffee cup chemical composition in terms of organic and chlorogenic acids, caffein and physicochemical parameters were correlated with perceived sourness and mouthfeel to better understand the influence of extracted compounds on the final beverage acidity. Statistical tools revealed that a major impact of chlorogenic acids emerged in pH and titratable acidity, while the sensorial sourness appeared more correlated with organic acids concentration. Thus, these findings suggests that organic acids could be potential predictors of beverage perceived acidity.

Multi-timescale neural dynamics for multisensory integration

Carrying out any everyday task, be it driving in traffic, conversing with friends or playing basketball, requires rapid selection, integration and segregation of stimuli from different sensory modalities. At present, even the most advanced artificial intelligence-based systems are unable to replicate the multisensory processes that the human brain routinely performs, but how neural circuits in the brain carry out these processes is still not well understood. In this Perspective, we discuss recent findings that shed fresh light on the oscillatory neural mechanisms that mediate multisensory integration (MI), including power modulations, phase resetting, phase-amplitude coupling and dynamic functional connectivity. We then consider studies that also suggest multi-timescale dynamics in intrinsic ongoing neural activity and during stimulus-driven bottom-up and cognitive top-down neural network processing in the context of MI. We propose a new concept of MI that emphasizes the critical role of neural dynamics at multiple timescales within and across brain networks, enabling the simultaneous integration, segregation, hierarchical structuring and selection of information in different time windows. To highlight predictions from our multi-timescale concept of MI, real-world scenarios in which multi-timescale processes may coordinate MI in a flexible and adaptive manner are considered.

Recent advances in photoluminescent fluorescent probe technology for food flavor compounds analysis

The real-time, precise qualitative and quantitative sensing of food flavor compounds is crucial for ensuring food safety, quality, and consumer acceptance. As indicators for food flavor labeling, it is vital to delve deep into the specific ingredient and content of food flavor compounds to assess the food flavor quality, but still facing huge challenges. Photoluminescent fluorescent probe technology, with fast detection and high sensitivity, has shown immense potentials in detecting food flavor compounds. In this review, the classification and optical sensing mechanism of photoluminescent fluorescent probe technology are described in detail. Besides, challenges in applying photoluminescent fluorescent probe technology to analyze food flavor compounds are outlined to indicate future research directions. We hope this review can provide an insight for the applications of photoluminescent fluorescent probe technology in the evaluation of food flavor quality in future.

Physicochemical characterization of a composite flour: Blending purple sweet potato and rice flours

In this study, the physicochemical characterization of different ratios of purple sweet potato flour (PSPF) and rice flour was investigated to improve the nutritional value and enrich the variety of rice-based staple food. The results showed that adding PSPF increased total dietary fiber and anthocyanin content whereas decreased amylose content of the composite flours. Additionally, the composite flours exhibited lower thermodynamic parameters and displayed darker, redder, and bluer colors. There were no noticeable changes in the functional group structure of the composite flours. The addition of PSPF decreased the crystallinity and water-holding capacity of the composite flours, whereas increased the average particle size and iodine blue value. PSPF increased the pasting temperature of the flours whereas decreased the breakdown and setback values. Overall, the addition of PSPF significantly affects the nutrition, color and physicochemical properties of the composite flours.

Potential of Bitter Medicinal Plants: A Review of Flavor Physiology

The function of the sense of taste is usually confined to the ability to perceive the flavor of food to assess and use the nutrients necessary for healthy survival and to discard those that may be harmful, toxic, or unpleasant. It is almost unanimously agreed that the perception of bitter taste prevents the consumption of toxins from plants, decaying foods, and drugs. Forty years ago, while practicing medicine in a rural area of the Colombian Amazon, I had an unexpected encounter with the Inga Indians. I faced the challenge of accepting that their traditional medicine was effective and that the medicinal plants they used had a real therapeutic effect. Wanting to follow a process of learning about medicinal plants on their terms, I found that, for them, the taste of plants is a primary and fundamental key to understanding their functioning. One of the most exciting results was discovering the therapeutic value of bitter plants. The present review aims to understand whether there is any scientific support for this hypothesis from the traditional world. Can the taste of plants explain their possible therapeutic benefit? In the last 20 years, we have made novel advances in the knowledge of the physiology of taste. Our purpose will be to explore these scientific advances to determine if the bitter taste of medicinal plants benefits human health.

Insights to Study, Understand and Manage Extruded Dry Pet Food Palatability

Pet food production is a fast-growing industry. While extruded dry pet food is the favored pet food due to its convenience of use, it may have poorer palatability than other pet foods such as wet pet foods. However, palatability plays a pivotal role in meeting nutritional requirements or providing therapeutic benefits in cats and dogs, as it ensures food acceptance. Thus, both academics and manufacturers conduct routine palatability tests to assess acceptance and preference of products among pets, alongside sensory analyses involving human panels. Palatability is greatly influenced by species-specific and environmental factors in cats and dogs. The review will hence present the current knowledge on palatability assessment and animal food perception; it will then aim to explore strategies for effectively managing palatability in dry pet food by examining the impact of key ingredients and process parameters on the finished product's palatability. Moreover, the demands and needs for sustainable and healthier products as well as supply constraints present novel challenges and opportunities for academics and manufacturers.

Inducing Novel Sound-Taste Correspondences via an Associative Learning Task

The interest in crossmodal correspondences, including those involving sounds and involving tastes, has experienced rapid growth in recent years. However, the mechanisms underlying these correspondences are not well understood. In the present study (N = 302), we used an associative learning paradigm, based on previous literature using simple sounds with no consensual taste associations (i.e., square and triangle wave sounds at 200 Hz) and taste words (i.e., sweet and bitter), to test the influence of two potential mechanisms in establishing sound-taste correspondences and investigate whether either learning mechanism could give rise to new and long-lasting associations. Specifically, we examined an emotional mediation account (i.e., using sad and happy emoji facial expressions) and a transitive path (i.e., sound-taste correspondence being mediated by color, using red and black colored squares). The results revealed that the associative learning paradigm mapping the triangle wave tone with a happy emoji facial expression induced a novel crossmodal correspondence between this sound and the word sweet. Importantly, we found that this novel association was still present two months after the experimental learning paradigm. None of the other mappings, emotional or transitive, gave rise to any significant associations between sound and taste. These findings provide evidence that new crossmodal correspondences between sounds and tastes can be created by leveraging the affective connection between both dimensions, helping elucidate the mechanisms underlying these associations. Moreover, these findings reveal that these associations can last for several weeks after the experimental session through which they were induced.

Metabolic state modulates neural processing of odors in the human olfactory bulb

The olfactory and endocrine systems have recently been shown to reciprocally shape the homeostatic processes of energy intake. As demonstrated in animal models, the individual's metabolic state dynamically modulates how the olfactory bulb process odor stimuli using a range of endocrine signals. Here we aimed to determine whether the neural processing of odors in human olfactory bulb is modulated by metabolic state. Participants were exposed to food-associated odors, in separate sessions being hungry and sated, while neural responses from the olfactory bulb was obtained using electrobulbogram. We found significantly higher gamma power activity (51-100 Hz) in the OB's response to odors during the Hunger compared to Sated condition. Specifically, EBG gamma power were elevated while hungry already at 100 ms after odor onset, thereby suggesting intra-bulbar modulation according to metabolic state. These results demonstrate that, akin to other animal models, hunger state affects OB activity in humans. Moreover, we show that the EBG method has the potential to measure internal metabolic states and, as such, could be used to study specificities in olfactory processing of individuals suffering from pathologies such as obesity or anorexia.

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

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

Impact of odorants on perception of sweetness by honey bees

Organic volatiles produced by fruits can result in overestimation of sweetness by humans, but it is unknown if a comparable phenomenon occurs in other species. Honey bees collect nectar of varying sweetness at different flowering plants. Bees discriminate sugar concentration and generally prefer higher concentrations; they encounter floral volatiles as they collect nectar, suggesting that they, like humans, could be susceptible to sweetness enhancement by odorant. In this study, limonene, linalool, geraniol, and 6-methyl-5-hepten-2-ol were tested for their ability to alter behaviors related to perception of sweetness by honey bees. Honey bees were tested in the laboratory using proboscis extension response-based assays and in the field using feeder-based assays. In the laboratory assays, 6-methyl-5-hepten-2-ol and geraniol, but neither linalool nor limonene, significantly increased responses to low concentrations of sucrose compared with no odorant conditions in 15-day and 25-day-old adult worker honey bees, but not in 35-day-old bees. Limonene reduced responding in 15-day-old bees, but not in the older bees. There was no odorant-based difference in performance in field assays comparing geraniol and limonene with a no odorant control. The interaction of the tested plant volatiles with sucrose concentration revealed in laboratory testing is therefore unlikely to be a major determinant of nectar choice by honey bees foraging under natural conditions. Because geraniol is a component of honey bee Nasonov gland pheromone as well as a floral volatile, its impact on responses in the laboratory may reflect conveyance of different information than the other odorants tested.

The Impact of the Foliar Application of Amino Acid Aqueous Fertilizer on the Flavor of Potato Tubers

The quality of the flavor of potatoes is a crucial determinant in the commercial success of a potato variety. Plant nutrition promotes the synthesis of amino acids, and the application of exogenous amino acids has the potential to enhance the flavor quality of potatoes. In this experiment, Dian Shu 1418 and Dian Shu 23 were used as the materials, and different amino acid foliar spray trials were designed. The free amino acid content in potato tubers is determined based on high-performance liquid chromatography, and volatile tuber flavor compounds are detected using gas chromatography-mass spectrometry. The results showed that the amino acid foliar spray effectively increased the content of glycine, methionine, and phenylalanine in the tubers, subsequently increasing the levels of 2,3-dimethyl-pyrazine and 2-ethyl-3-methyl-pyrazine, enhancing the roasted fragrance characteristics of the potatoes. The experimental results provide a reference for cultivating flavor enhancement in potato tubers.

How much is a chef's touch worth? Affective, emotional and behavioural responses to food images: A multimodal study

BACKGROUND

Food aesthetics influences affective dimensions (valence and arousal) and subsequent emotional and behavioural responses in images presented in more traditional form, almost rustic in some cases, to the signature dishes of haute cuisine. However, the visual impact of images of haute cuisine dishes on consumers' affective and emotional responses compared to traditional dishes is still understudied.

METHODS

We recorded electrodermal activity, ocular movements and self-report affect of 35 volunteers while they performed a picture viewing paradigm using images of haute cuisine food, traditional food, and non-food. Additionally, the moderating role of age was examined.

RESULTS

Our results showed that subjects had higher feelings of pleasure and arousal toward images of food (haute cuisine and traditional dishes) compared to non-food images. However, no difference in self-report affect, physiological and behavioural responses was found between haute cuisine and traditional dishes. Interestingly, a moderating effect of age was revealed, reporting that younger participants had greater feelings of pleasure and shorter eye-to-screen distance towards traditional food than haute cuisine.

CONCLUSIONS

As a whole, our findings suggest that food aesthetics could at least partially affect consumers' affective and emotional responses. Interestingly, physiological responses to food pictures seemed to be relatively independent of approach/avoidance motivational states, supporting the assumption that traditional visual restaurant menus with attractive images might be insufficient for eliciting intense positive emotions. This study also contributes to advancing the understanding of the role that age plays in emotional impact when images of haute cuisine dishes are presented to consumers.

A supervised learning regression method for the analysis of oral sensitivity of healthy individuals and patients with chemosensory loss

The gustatory, olfactory, and trigeminal systems are anatomically separated. However, they interact cognitively to give rise to oral perception, which can significantly affect health and quality of life. We built a Supervised Learning (SL) regression model that, exploiting participants' features, was capable of automatically analyzing with high precision the self-ratings of oral sensitivity of healthy participants and patients with chemosensory loss, determining the contribution of its components: gustatory, olfactory, and trigeminal. CatBoost regressor provided predicted values of the self-rated oral sensitivity close to experimental values. Patients showed lower predicted values of oral sensitivity, lower scores for measured taste, spiciness, astringency, and smell sensitivity, higher BMI, and lower levels of well-being. CatBoost regressor defined the impact of the single components of oral perception in the two groups. The trigeminal component was the most significant, though astringency and spiciness provided similar contributions in controls, while astringency was most important in patients. Taste was more important in controls while smell was the least important in both groups. Identifying the significance of the oral perception components and the differences between the two groups provide important information to allow for more targeted examinations supporting both patients and healthcare professionals in clinical practice.

Concepts require flexible grounding

Research on semantic memory has a problem. On the one hand, a robust body of evidence implicates sensorimotor regions in conceptual processing. On the other hand, a different body of evidence implicates a modality independent semantic system. The standard solution to this tension is to posit a hub-and-spoke system with modality independent hubs and modality specific spokes. In this paper, I argue in support of an alternative view of grounding which remains committed to neural reenactment but emphasizes the multimodal and multilevel nature of the semantic system. This view is built upon the recognition that abstraction is a design feature of concepts. Semantic memory employs hierarchically structured representations to capture different degrees of abstraction. Grounding does not work the way that many embodied approaches have assumed.

Modelling of perceived sweetness in biscuits based on sensory analysis as a new tool to evaluate reformulation performance in sugar reduction studies

Sugar reduction in foods is of global interest in food science and industry to limit excessive calorie intake for healthier nutrition. Therefore, a modified Weibull model-based approach is presented here to relate sweetness perception with sugar concentration for the first time. The model was tested by using sweetness perception data obtained from sensory analysis of biscuits (wholewheat flour, whey or hydrolysed pea protein, different sucrose forms, ethylvanillin, furaneol, phenylacetaldehyde) using a line scale and untrained panellists. Sweetness scores increased 56%, 59%, 41% by the addition of wholewheat flour, proteins, or aroma compounds at 17% sucrose containing biscuits, respectively. Wholewheat flour and proteins boosted Maillard reaction products imparting baked/caramel-like flavour. The Weibull model well fitted to the sweetness perception data with a sigmoidal curve and high predicting power. This approach allows to explain how much sugar reduction can be achieved to reach a targeted sweetness perception without performing further sensory analysis.

Dedicated odor-taste stimulation design for fMRI flavor studies

BACKGROUND

Flavor is a mental representation that results from the brain's integration of at least odor and taste, and fMRI can highlight brain-related areas. However, delivering stimuli during fMRI can be challenging especially when administrating liquid stimuli in supine position. It remains unclear how and when odorants are released in the nose and how to improve odorant release.

NEW METHOD

We used a proton transfer reaction mass spectrometer (PTR-MS) to monitor the in vivo release of odorants via the retronasal pathway during retronasal odor-taste stimulation in a supine position. We tested techniques to improve odorant release, including avoiding or delaying swallowing and velum open training (VOT).

RESULTS

Odorant release was observed during retronasal stimulation, before swallowing, and in a supine position. VOT did not improve odorant release. Odorant release during stimulation had a latency more optimal for fitting with BOLD timing than after swallowing.

COMPARISON WITH EXISTING METHOD(S)

Previous in vivo measurements of odorant release under fMRI-like conditions showed that odorant release occurred only after swallowing. On the contrary, a second study found that aroma release could occur before swallowing, but participants were sitting.

CONCLUSION

Our method shows optimal odorant release during the stimulation phase, meeting the criteria for high-quality brain imaging of flavor processing without swallowing-related motion artifacts. These findings provide an important advancement in understanding the mechanisms underlying flavor processing in the brain.

How infant food likes become established as knowledge: Parental food assessments during infant mealtimes in the home

Early infancy is a critical period for the development of food likes and dislikes, but very little is known about the role of the social context and parent-child interaction within this process, and even less about what happens in the home environment. The current paper addresses this issue by examining how and when parents utter food assessments about their infants' eating practices during mealtimes in the home, and the practices through which infant likes become established as knowledge. A data corpus of 77 video-recorded infant mealtimes from six infants (aged 5-9 months) and their parents was analysed using discursive psychology, with a specific focus on the use of object-side and subject-side assessments. Data were recorded in English-speaking family homes in Scotland and Sweden. The analysis highlights three key findings: (1) infants' interactional rights to assess food are invoked during first tastes, (2) infants' food likes are established through anchoring in family food preferences and as shared knowledge among family members, and (3) infants' potential food dislikes are challenged by parents using object-side assessments and claims about previous likes. Parents thus play a crucial role in the establishment of infant food likes through the formulation of subject-side category assessments during early infant mealtimes. The research suggests that more focus should be placed on examining infant eating practices as collaborative and interactional events in everyday contexts.

Sensory test A-Not A rating signal detection: panel’s sensory learning and stability of decision criteria

Signal detection theory (SDT) sensory discrimination analysis using A-Not A with a two-step rating is an efficient approach to in-house sensory quality management in the food industry. For such sensory analysis using an internal panel, the panels' ability to use stable decision criteria and provide a consistent response distribution responding to "A" vs "Not A" is critical for guaranteeing the data quality. This study examined the effects of the familiarization procedure (FP) and reference presentation probability (RPP) in the SDT A-Not A rating protocol on the panels' sensory learning of samples and stability of decision criteria using SDT parameters, recognition d' (d'_Rec),criteria location (c), and discrimination d' indices. Three different protocols were compared using ice-tea samples with small differences: Control, 0.25 RPP with repeated reference tasting (FP_R); Modified-1, 0.25 RPP with reference categorization (FP_C); Modified-2, 0.5 RPP with reference categorization (FP_C). An independent sample design with three groups having equal sensitivity was used to identify the differences among the protocols. For each protocol, two sub-groups with similar decision criteria (response bias) were formed according to the results obtained from the pre-test and used for the main-test analysis. SDT analysis results indicated that the Modified-2 protocol with a higher RPP (0.5) induced the most efficient sensory learning of the reference. The protocol improved the subjects' recognition of the reference and test samples, better differentiating from the reference and stabilizing the decision criterion, resulting in higher discrimination performance (larger d'). The results showed that d'_Rec analysis, together with d' analysis using a sensory panel, is a useful tool for monitoring the panel performance and checking for the sensory data quality of the sensory difference tests. In the present paper, a detailed illustration of the A-Not A sensory test procedure and examples of how to apply the SDT indices for different business decision-making is also introduced using the design and results of the present experiment.

Taste and smell abnormalities in advanced cancer: Negative impact on subjective food intake

BACKGROUND

Taste and smell abnormalities (TSAs) are present in all cancer stages and may contribute to malnutrition. Despite this, they are rarely screened for. This study examined the prevalence and characteristics of TSAs and their influence on subjective food intake in advanced cancer.

METHODS

Consecutive patients with advanced cancer were recruited. A modified Taste and Smell Survey assessed subjective TSAs. Objective TSAs were assessed with validated taste strips and "Sniffin Sticks." A six-item food intake questionnaire identified any effect TSAs had on food preferences/aversions. Nutrition status was evaluated with the abridged Patient-Generated Subjective Global Assessment.

RESULTS

All 30 participants had either subjective or objective TSAs. The prevalence of TSAs varied based on the assessment tool used. Participants were more aware of taste changes (TCs) than smell changes (SCs). TCs caused reduced food intake in 13 participants. Six reported SCs affected food intake. Food choices caused by TSAs were inconsistent. Some foods preferred because of TSAs were avoided by other participants. None received nutrition counseling on TSA management. Almost all were at malnutrition risk (97%). Almost half (47%) felt TSAs reduced quality of life (QoL). Participants reported "not looking forward to meals" and "can't sit down and eat anything" because of TSAs.

CONCLUSION

TSAs were highly prevalent and impactful on food intake. Both TCs and SCs were complex and varied on an individual basis. Despite the effect on health and QoL, no patients received any nutrition counseling on TSA management. Individualized screening and advice are needed for TSAs in advanced cancer.

Multisensory integration of orally-sourced gustatory and olfactory inputs to the posterior piriform cortex in awake rats

Flavour refers to the sensory experience of food, which is a combination of sensory inputs sourced from multiple modalities during consumption, including taste and odour. Previous work has demonstrated that orally-sourced taste and odour cues interact to determine perceptual judgements of flavour stimuli, although the underlying cellular- and circuit-level neural mechanisms remain unknown. We recently identified a region of the piriform olfactory cortex in rats that responds to both taste and odour stimuli. Here, we investigated how converging taste and odour inputs to this area interact to affect single neuron responsiveness ensemble coding of flavour identity. To accomplish this, we recorded spiking activity from ensembles of single neurons in the posterior piriform cortex (pPC) in awake, tasting rats while delivering taste solutions, odour solutions and taste + odour mixtures directly into the oral cavity. Our results show that taste and odour inputs evoke highly selective, temporally-overlapping responses in multisensory pPC neurons. Comparing responses to mixtures and their unisensory components revealed that taste and odour inputs interact in a non-linear manner to produce unique response patterns. Taste input enhances trial-by-trial decoding of odour identity from small ensembles of simultaneously recorded neurons. Together, these results demonstrate that taste and odour inputs to pPC interact in complex, non-linear ways to form amodal flavour representations that enhance identity coding. KEY POINTS: Experience of food involves taste and smell, although how information from these different senses is combined by the brain to create our sense of flavour remains unknown. We recorded from small groups of neurons in the olfactory cortex of awake rats while they consumed taste solutions, odour solutions and taste + odour mixtures. Taste and smell solutions evoke highly selective responses. When presented in a mixture, taste and smell inputs interacted to alter responses, resulting in activation of unique sets of neurons that could not be predicted by the component responses. Synergistic interactions increase discriminability of odour representations. The olfactory cortex uses taste and smell to create new information representing multisensory flavour identity.

Olfactory-gustatory simultaneity judgments: A preliminary study on the congruency-dependent temporal window of multisensory binding

BACKGROUND

A greater congruency of audio and video expands the temporal binding window (TBW). A similar phenomenon may occur with a combination of odor and taste, which are the main components of flavor.

OBJECTIVE

TBW is defined as the temporal resolution of synchrony perception. The larger the TBW, the lower the resolution. We hypothesized that the more congruent the odor and taste, the lower the temporal resolution of synchrony perception.

METHODS

To examine this hypothesis, 10 female participants performed simultaneity judgment (SJ) tasks under congruent (soy sauce odor with saline) and incongruent (cherry tree leaf odor with saline) conditions and evaluated the congruency with saltiness for the two odors. In the SJ tasks, participants reported whether odor and taste were presented simultaneously or successively. We assumed a Gaussian distribution for the temporal distributions of the simultaneous response rates and calculated the approximations. In addition, we computed the half width at half height (HWHH) as an index of TBW based on the coefficient of approximation for the temporal distribution of the simultaneous response rates.

RESULTS

HWHH was significantly larger under congruent condition than under incongruent condition. In addition, congruency with saltiness had a significant moderate positive correlation with HWHH.

CONCLUSION

The larger the HWHH, the lower the temporal resolution of synchrony perception, supporting the hypothesis. This study suggests that the width of TBW depends on the cross-modal congruency similar to the case for audio-visual SJs. However, methodological improvements, including a larger sample size and gender-independent recruitment of participants, are essential to enhance the reliability of the findings because some of the results did not provide sufficient ESs or power.

Recent advance in technological innovations of sugar-reduced products

Sugar is crucial as an essential nutrient for humans as well as for providing texture, sweetness and so on to food. But with the rise in people's pursuit of health, it is becoming increasingly clear that excessive consumption of sugar can locate a load on the body. It has been that excessive sugar is associated with many diseases, such as dental caries, obesity, diabetes, and coronary heart disease. Therefore, researchers and industries are trying to reduce or substitute sugar in food without affecting the sensory evaluation. Substituting sugar with sweeteners is alternatively becoming the most traditional way to minimize its use. So far, the sweeteners such as stevia and xylitol have been are commercially applied. Several studies have shown that technological innovation can partially compensate for the loss in sweetness as a result of sugar reduction, such as cross-modal interactions that stimulate sweetness with aroma, nanofiltration that filters disaccharides and above, enzyme-catalyzed sugar hydrolysis, and microbial fermentation that turns sugar into sugar alcohol. This review summarizes these studies to enhance the safety and quality of sugar-reduced products, and will provide some theoretical frameworks for the food industry to reduce sugar in foods, meet consumers' needs, and promote human health.

Formation and Analysis of Volatile and Odor Compounds in Meat-A Review

The volatile composition and odor of meat and meat products is based on the precursors present in the raw meat. These are influenced by various pre-slaughter factors (species, breed, sex, age, feed, muscle type). Furthermore, post-mortem conditions (chiller aging, cooking conditions, curing, fermentation, etc.) determine the development of meat volatile organic compounds (VOCs). In this review, the main reactions leading to the development of meat VOCs such as the Maillard reaction; Strecker degradation; lipid oxidation; and thiamine, carbohydrate, and nucleotide degradation are described. The important pre-slaughter factors and post-mortem conditions influencing meat VOCs are discussed. Finally, the pros, cons, and future perspectives of the most commonly used sample preparation techniques (solid-phase microextraction, stir bar sorptive extraction, dynamic headspace extraction) and analytical methods (gas chromatography mass spectrometry and olfactometry, as well as electronic noses) for the analysis of meat VOCs are discussed, and the continued importance of sensorial analysis is pinpointed.

Alcohol acyl transferase genes at a high-flavor intensity locus contribute to ester biosynthesis in kiwifruit

Volatile esters are key compounds contributing to flavor intensity in commonly consumed fruits including apple (Malus domestica), strawberry (Fragaria spp.), and banana (Musa sapientum). In kiwifruit (Actinidia spp.), ethyl butanoate and other esters have been proposed to contribute fruity, sweet notes to commercial cultivars. Here, we investigated the genetic basis for ester production in Actinidia in an A. chinensis mapping population (AcMPO). A major quantitative trait loci for the production of multiple esters was identified at the high-flavor intensity (HiFI) locus on chromosome 20. This locus co-located with eight tandemly arrayed alcohol acyl transferase genes in the Red5 genome that were expressed in a ripening-specific fashion that corresponded with ester production. Biochemical characterization suggested two genes at the HiFI locus, alcohol acyl transferase 16-b/c (AT16-MPb/c), probably contributed most to the production of ethyl butanoate. A third gene, AT16-MPa, probably contributed more to hexyl butanoate and butyl hexanoate production, two esters that segregated in AcMPO. Sensory analysis of AcMPO indicated that fruit from segregating lines with high ester concentrations were more commonly described as being "fruity" as opposed to "beany". The downregulation of AT16-MPa-c by RNAi reduced ester production in ripe "Hort16A" fruit by >90%. Gas chromatography-olfactometry indicated the loss of the major "fruity" notes contributed by ethyl butanoate. A comparison of unimproved Actinidia germplasm with those of commercial cultivars indicated that the selection of fruit with high concentrations of alkyl esters (but not green note aldehydes) was probably an important selection trait in kiwifruit cultivation. Understanding ester production at the HiFI locus is a critical step toward maintaining and improving flavor intensity in kiwifruit.

Trigeminal Stimulus Menthol Masks Bitter Off-Flavor of Artificial Sweetener Acesulfame-K

Consumer health concerns and regulatory policies lead to a growing demand for sugar-sweetened beverage alternatives. A reduced energy content can be achieved using artificial sweeteners, which often also convey a metallic or bitter off-flavor. Therefore, the alteration of sweetness perception and masking of potential off-flavors are paramount for improving sweet beverages. Trigeminal stimuli, such as capsaicin (spicy) or menthol (cooling), have been used to influence taste perception in food items, although their use in beverages has not yet been systematically investigated. Here, the influence of menthol on sweetness perception in an aqueous solution is examined both on the sensory and psychophysiological level. The addition of menthol had no sensory effect on sweetness perception; however, psychophysiological measurements suggest a boost in the physiological response to cold perception through the addition of sugar. Moreover, menthol addition shifted the recognition threshold of unpleasant bitterness of the sweetener acesulfame-K from 21.35 to 36.93 mg/L, masking the off-flavor. These findings illuminate the complexity of trigeminal perception influences on taste. Further investigation of these effects can render trigeminal stimuli an effective tool to enhance beverage aroma and flavor.

Searching for perceptual similarity within, and between, the (chemical) senses

In this narrative historical review, I want to take a closer look at the concept of perceptual similarity both as it applies within, and between, the chemical senses (specifically taste and smell). The discussion is linked to issues of affective similarity and connotative meaning. The relation between intramodal and crossmodal judgments of perceptual similarity, and the putatively special status of those odorants that happen to take on taste qualities will also be discussed. An important distinction is drawn between the interrelated, though sometimes distinct, notions of perceptual similarity and crossmodal congruency, specifically as they relate to the comparison of chemosensory stimuli. Such phenomena are often referred to as crossmodal correspondences, or by others (incorrectly in my view), as a kind of ubiquitous synesthesia.

Odor-Induced Taste Enhancement Is Specific to Naturally Occurring Temporal Order and the Respiration Phase

Interaction between odor and taste information creates flavor perception. There are many possible determinants of the interaction between odor and taste, one of which may be the somatic sensations associated with breathing. We assumed that a smell stimulus accompanied by inhaling or exhaling enhances taste intensity if the order is congruent with natural drinking. To present an olfactory stimulus from the identical location during inhalation and exhalation, we blocked the gap between the tube presenting the olfactory stimulus and the nostril. Participants breathed and ingested the solution according to the instructions on the screen and evaluated the solution's taste intensity. Vanilla odor enhanced the sweet taste in both retronasal and orthonasal conditions when the order of stimuli was congruent with natural drinking, but it did not do so in either condition when they were incongruent. The results suggest that breathing is a determinant of odor-taste interaction. The methods of presenting olfactory stimuli used in this study were compared and discussed in relation to those used in previous studies. Odor-induced taste enhancement depends on the time order of smell with breathing and taste congruency in natural drinking. Taste enhancement was induced by odor in both conditions by minimizing differences in odor presentation between them.

Auditory perception dominates in motor rhythm reproduction

It is commonly agreed that vision is more sensitive to spatial information, while audition is more sensitive to temporal information. When both visual and auditory information are available simultaneously, the modality appropriateness hypothesis predicts that, depending on the task, the most appropriate (i.e., reliable) modality dominates perception. While previous research mainly focused on discrepant information from different sensory inputs to scrutinize the modality appropriateness hypothesis, the current study aimed at investigating the modality appropriateness hypothesis when multimodal information was provided in a nondiscrepant and simultaneous manner. To this end, participants performed a temporal rhythm reproduction task for which the auditory modality is known to be the most appropriate. The experiment comprised an auditory (i.e., beeps), a visual (i.e., flashing dots), and an audiovisual condition (i.e., beeps and dots simultaneously). Moreover, constant as well as variable interstimulus intervals were implemented. Results revealed higher accuracy and lower variability in the auditory condition for both interstimulus interval types when compared to the visual condition. More importantly, there were no differences between the auditory and the audiovisual condition across both interstimulus interval types. This indicates that the auditory modality dominated multimodal perception in the task, whereas the visual modality was disregarded and hence did not add to reproduction performance.

The Challenge of Measuring Sweet Taste in Food Ingredients and Products for Regulatory Compliance: A Scientific Opinion

The Codex Alimentarius Commission, a central part of the joint Food and Agricultural Organization/World Health Organizations Food Standards Program, adopts internationally recognized standards, guidelines, and code of practices that help ensure safety, quality, and fairness of food trade globally. Although Codex standards are not regulations per se, regulatory authorities around the world may benchmark against these standards or introduce them into regulations within their countries. Recently, the Codex Committee on Nutrition and Foods for Special Dietary Uses (CCNFSDU) initiated a draft revision to the Codex standard for follow-up formula (FUF), a drink/product (with added nutrients) for young children, to include requirements for limiting or measuring the amount of sweet taste contributed by carbohydrates in a product. Stakeholders from multiple food and beverage manufacturers expressed concern about the subjectivity of sweetness and challenges with objective measurement for verifying regulatory compliance. It is a requirement that Codex standards include a reference to a suitable method of analysis for verifying compliance with the standard. In response, AOAC INTERNATIONAL formed the Ad Hoc Expert Panel on Sweetness in November 2020 to review human perception of sweet taste, assess the landscape of internationally recognized analytical and sensory methods for measuring sweet taste in food ingredients and products, deliver recommendations to Codex regarding verification of sweet taste requirements for FUF, and develop a scientific opinion on measuring sweet taste in food and beverage products beyond FUF. Findings showed an abundance of official analytical methods for determining quantities of carbohydrates and other sweet-tasting molecules in food products and beverages, but no analytical methods capable of determining sweet taste. Furthermore, sweet taste can be determined by standard sensory analysis methods. However, it is impossible to define a sensory intensity reference value for sweetness, making them unfit to verify regulatory compliance for the purpose of international food trade. Based on these findings and recommendations, the Codex Committee on Methods of Analysis and Sampling agreed during its 41st session in May 2021 to inform CCNFSDU that there are no known validated methods to measure sweetness of carbohydrate sources; therefore, no way to determine compliance for such a requirement for FUF.

Gustatory dysfunction in patients with olfactory dysfunction and the associated factors

BACKGROUND

Little is known about the occurrence of gustatory dysfunction (GD) in relation to different aetiologies of olfactory dysfunction (OD) as assessed by psychophysical chemosensory tests. The aim of this study was to analyse gustatory function in patients with OD and to investigate clinical factors associated with GD.

METHODS

A total of 742 individuals who underwent both olfactory and gustatory function tests at a tertiary medical centre from November 2019 to March 2021 were retrospectively enrolled. Olfactory and gustatory function were assessed by the YSK olfactory and gustatory function tests, respectively. Patients with OD were classified into four groups according to the aetiology: sinonasal disease, post-infection OD (PIOD), post-traumatic OD (PTOD), and others. Secondary outcomes included age, sex, smoking history, and alcohol history.

RESULTS

Among the 488 patients with OD, 93 (19.1%) showed GD and 395 (80.9%) had normal gustatory function. Only 25 (9.8%) among 254 individuals with normosmia showed GD. Analyses of these frequencies revealed a significant association between OD and GD. In addition, the taste score was significantly lower in patients with OD than individuals with normosmia. The frequency of GD was significantly higher in patients with PTOD (53.6%) than in those with OD of other aetiologies (sinonasal disease, 6.7%; PIOD, 13.0%; others, 24.4%). In the multivariate analysis, age ≥55 years and PTOD were associated with a high frequency of GD among patients with OD.

CONCLUSIONS

The current study show that GD is significantly associated with OD. In particular, GD is more common in patients with PTOD than in those with OD of other aetiologies.

Why Taste Is Pharmacology

The chapter presents an argument supporting the view that taste, defined as the receptor-mediated signaling of taste cells and consequent sensory events, is proper subject matter for the field of pharmacology. The argument develops through a consideration of how the field of pharmacology itself is to be defined. Though its application toward the discovery and development of therapeutics is of obvious value, pharmacology nevertheless is a basic science committed to examining biological phenomena controlled by the selective interactions between chemicals - regardless of their sources or uses - and receptors. The basic science of pharmacology is founded on the theory of receptor occupancy, detailed here in the context of taste. The discussion then will turn to consideration of the measurement of human taste and how well the results agree with the predictions of receptor theory.

Sensory and chemical characterization of Chinese bog bilberry wines using Check-all-that-apply method and GC-Quadrupole-MS and GC-Orbitrap-MS analyses

The sensory and chemical profiles of commercial bog bilberry (BB) wines were investigated using a multi-analytical approach. Sensory test included scaling and check-all-that-apply (CATA) method with questions on liking of BB wine. The sensory data was correlated with their volatile compound profiles determined using gas chromatography coupled with quadrupole and orbitrap mass spectrometry (GC-Quadrupole/Orbitrap-MS). In general, all BB wines were characterized with "fruity", "blueberry" and "floral" odors and "sour", "mouth puckering" and "sweet" flavors. Samples more frequently characterized as "fruity" and "floral" in CATA were preferred by the panelists (n = 93). High relative proportions of o-cymene, p-cymenene, 1-octen-3-one and 3-ethylphenol in a sample (described as "ginger" and "chili") resulted in a lower liking rating. Similarly, generally disliked sample described with "Chinese herbs" and "licorice" was characterized by compounds 3-methylpentan-1-ol, 1,1,6-trimethyl-1,2-dihydronaphthalene, and 4-vinylphenol. The data will give novel information for berry wine and beverage industry on the quality factors of BB wines linked to higher acceptance.

Technologies for Multimodal Interaction in Extended Reality—A Scoping Review

When designing extended reality (XR) applications, it is important to consider multimodal interaction techniques, which employ several human senses simultaneously. Multimodal interaction can transform how people communicate remotely, practice for tasks, entertain themselves, process information visualizations, and make decisions based on the provided information. This scoping review summarized recent advances in multimodal interaction technologies for head-mounted display-based (HMD) XR systems. Our purpose was to provide a succinct, yet clear, insightful, and structured overview of emerging, underused multimodal technologies beyond standard video and audio for XR interaction, and to find research gaps. The review aimed to help XR practitioners to apply multimodal interaction techniques and interaction researchers to direct future efforts towards relevant issues on multimodal XR. We conclude with our perspective on promising research avenues for multimodal interaction technologies.

Dysgeusia: A review in the context of COVID-19

Background

Taste disorders in general, and dysgeusia in particular, are relatively common disorders that may be a sign of a more complex acute or chronic medical condition. During the COVID-19 pandemic, taste disorders have found their way into the realm of general as well as specialty dentistry, with significance in screening for patients who potentially may have the virus.

Types of Studies Reviewed

The authors searched electronic databases (PubMed, Embase, Web of Science, Google Scholar) for studies focused on dysgeusia, ageusia, and other taste disorders and their relationship to local and systemic causes.

Results

The authors found pertinent literature explaining the normal physiology of taste sensation, proposals for suggested new tastes, presence of gustatory receptors in remote tissues of the body, and etiology and pathophysiology of taste disorders, in addition to the valuable knowledge gained about gustatory disorders in the context of COVID-19. Along with olfactory disorders, taste disorders are one of the earliest suggestive symptoms of COVID-19 infection.

Conclusions

Gustatory disorders are the result of local or systemic etiology or both. Newer taste sensations, such as calcium and fat tastes, have been discovered, as well as taste receptors that are remote from the oropharyngeal area. Literature published during the COVID-19 pandemic to date reinforces the significance of early detection of potential patients with COVID-19 by means of screening for recent-onset taste disorders.

Practical Implications

Timely screening and identification of potential gustatory disorders are paramount for the dental care practitioner to aid in the early diagnosis of COVID-19 and other serious systemic disorders.

In-mouth attributes driving perceived quality of Pinot noir wines: Sensory and chemical characterisation

We investigated perception of mouthfeel in Pinot noir wines and its physicochemical determinants. Seventeen wine professionals judged 18 Pinot noir wines via two tasting tasks, Descriptive Rating and Directed Sorting, the latter based on perception of in-mouth attributes. Selected chemical measures of the same 18 wines were determined. Sensory results demonstrated that mouthfeel attributes driving high quality were smoothness/silky/velvety, volume/fullness/roundness, overall body, and viscosity/mouth-coating, while the taste of bitterness and perceived tannin harshness drove low quality judgments. Perceived astringency and expressions of tannin (e.g., soft; harsh; fine) drove sorting behaviour of participants. Partial least squares regression (PLSR) was used to associate perceived in-mouth phenomena and chemical composition. The phenolic profile, in particular tannin concentration and structure, was the most important predictor of astringency and its sub-components. These results have important implications for wine producers aiming to enhance perceived quality in their Pinot noir wines.

E-Nose and Olfactory Assessment: Teamwork or a Challenge to the Last Data? The Case of Virgin Olive Oil Stability and Shelf Life

Electronic nose (E-nose) devices represent one of the most trailblazing innovations in current technological research, since mimicking the functioning of the biological sense of smell has always represented a fascinating challenge for technological development applied to life sciences and beyond. Sensor array tools are right now used in a plethora of applications, including, but not limited to, (bio-)medical, environmental, and food industry related. In particular, the food industry has seen a significant rise in the application of technological tools for determining the quality of edibles, progressively replacing human panelists, therefore changing the whole quality control chain in the field. To this end, the present review, conducted on PubMed, Science Direct and Web of Science, screening papers published between January 2010 and May 2021, sought to investigate the current trends in the usage of human panels and sensorized tools (E-nose and similar) in the food industry, comparing the performances between the two different approaches. In particular, the focus was mainly addressed towards the stability and shelf life assessment of olive oil, the main constituent of the renowned “Mediterranean diet”, and nowadays appreciated in cuisines from all around the world. The obtained results demonstrate that, despite the satisfying performances of both approaches, the best strategy merges the potentialities of human sensory panels and technological sensor arrays, (i.e., E-nose somewhat supported by E-tongue and/or E-eye). The current investigation can be used as a reference for future guidance towards the choice between human panelists and sensorized tools, to the benefit of food manufacturers.

In Vivo Aroma Release and Dynamic Sensory Perception of Composite Foods

Condiments such as spreads, dressings, or sauces are usually consumed together with carrier foods such as breads or vegetables. Dynamic interactions between condiments and carriers occur during consumption, which can influence aroma release and perception. This study investigated in vivo aroma release (PTR-MS) and dynamic sensory perception (time-intensity) of mayonnaises spiked with lemon aroma (limonene, citral). Mayonnaises were assessed without and with carrier foods (bread, potato). When different mayonnaises were consumed and assessed alone, aroma release and intensity perception were positively correlated. Interestingly, when mayonnaises were combined with carriers, aroma release and perception were no longer positively correlated. Addition of carriers increased release of limonene and citral into the nasal cavity during consumption but decreased perceived aroma intensity of condiments. The increase in aroma release induced by the carriers can be explained by differences in oral processing behaviors and by the increased surface area of mayonnaise-carrier combinations. Carrier addition is likely to modulate aroma perception of composite foods by cross-modal texture-aroma interactions. This work demonstrates that not only physicochemical characteristics of foods but also cross-modal interactions play a role in influencing flavor perception of composite foods.

Effective Connectivity in the Human Brain for Sour Taste, Retronasal Smell, and Combined Flavour

The anterior insula and rolandic operculum are key regions for flavour perception in the human brain; however, it is unclear how taste and congruent retronasal smell are perceived as flavours. The multisensory integration required for sour flavour perception has rarely been studied; therefore, we investigated the brain responses to taste and smell in the sour flavour-processing network in 35 young healthy adults. We aimed to characterise the brain response to three stimulations applied in the oral cavity—sour taste, retronasal smell of mango, and combined flavour of both—using functional magnetic resonance imaging. Effective connectivity of the flavour-processing network and modulatory effect from taste and smell were analysed. Flavour stimulation activated middle insula and olfactory tubercle (primary taste and olfactory cortices, respectively); anterior insula and rolandic operculum, which are associated with multisensory integration; and ventrolateral prefrontal cortex, a secondary cortex for flavour perception. Dynamic causal modelling demonstrated that neural taste and smell signals were integrated at anterior insula and rolandic operculum. These findings elucidated how neural signals triggered by sour taste and smell presented in liquid form interact in the brain, which may underpin the neurobiology of food appreciation. Our study thus demonstrated the integration and synergy of taste and smell.

Relationship between Anthropometric Parameters and Sensory Processing in Typically Developing Brazilian Children with a Pediatric Feeding Disorder

In this study, we aimed to relate anthropometric parameters and sensory processing in typically developing Brazilian children diagnosed with a pediatric feeding disorder (PFD). This was a retrospective study of typically developing children with a PFD. Anthropometric data were collected and indices of weight-for-age, length/height-for-age, and body mass index-for-age (BMI-for-age) were analyzed as z-scores. Sensory profile data were collected for auditory, visual, tactile, vestibular, and oral sensory processing. We included 79 medical records of children with a PFD. There were no statistically significant (p > 0.05) relationships between the anthropometric variables (weight-, length/height-, or BMI-for-age) and the sensory variables (auditory, visual, tactile, vestibular, or oral sensory processing). In conclusion, we found no relationship between anthropometric parameters and sensory processing in the sample of typically developing Brazilian children diagnosed with a PFD under study.

Measuring the Effect of Blockchain Extrinsic Cues on Consumers' Perceived Flavor and Healthiness: A Cross-Country Analysis

Many studies in the related literature have proven that the perception of flavor and healthiness can be affected by both the product’s intrinsic and extrinsic cues. Package designs, brands, colors, labels and other visual elements exert and influence consumers’ expectations and guide them toward food decisions. With the increasing initiatives promoted within Europe in support of the adoption of blockchain technology in supply chains and agri-food contexts, in the coming years, packages will be used with additional product information certified with the technology itself. Cueing packages with blockchain-certified information could affect consumers in their overall flavor and health perceptions, similarly to that previously demonstrated with other extrinsic cues. In the present study, we analyzed a sample of 310 primary grocery shoppers from Germany, Italy and the UK, demonstrating the effectiveness of technology-certified information on the package of animal milk in influencing consumers’ flavor and health perceptions and exploring the differences and similarities across the three countries and milk categories.

Effects of auditory feedback on gait behavior, gaze patterns and outcome performance in long jumping

In the current study, we conducted two experiments to investigate the impact of concurrent, action-induced auditory feedback on gait patterns, gaze behavior and outcome performance in long jumping. In Experiment 1, we examined the effects of present vs. absent auditory feedback on gait, gaze and performance outcome measures. Results revealed a significant interaction effect between condition (present vs. absent auditory feedback) and phase (acceleration vs. zeroing-in phase) on participants' step lengths indicating that the absence (rather than the presence) of auditory feedback led to facilitatory effects in terms of a more prototypical gait pattern (i.e., shorter steps in the acceleration phase and longer steps in the zeroing-in phase). Similarly, the absent auditory feedback led to a higher gaze stability in terms of less switches between areas of interest (AOIs). However, there was no effect on jumped distance. In Experiment 2, we scrutinized the influence of concurrent vs. delayed auditory feedback on all three performance parameters. In contrast to concurrent feedback, delayed auditory feedback negatively affected all three measures: participants showed (i) dysfunctional deviations from their prototypical gait pattern (i.e., shorter steps across both phases of the run-up), (ii) less stable, maladaptive gaze patterns (i.e., more switches between AOIs) and (iii) poorer jumping performance (i.e., shorter jumped distances). Together, the two experiments provide clear evidence for the impact of concurrent, action-induced auditory feedback on the coordination of complex, rhythmical motor tasks such as the long jump.

Chromatographic Fingerprinting Strategy to Delineate Chemical Patterns Correlated to Coffee Odor and Taste Attributes

Coffee cupping includes both aroma and taste, and its evaluation considers several different attributes simultaneously to define flavor quality and therefore requires complementary data from aroma and taste. This study investigates the potential and limits of a data-driven approach to describe the sensory quality of coffee using complementary analytical techniques usually available in routine quality control laboratories. Coffee flavor chemical data from 155 samples were obtained by analyzing volatile (headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS)) and nonvolatile (liquid chromatography-ultraviolet/diode array detector (LC-UV/DAD)) fractions, as well as from sensory data. Chemometric tools were used to explore the data sets, select relevant features, predict sensory scores, and investigate the networks between features. A comparison of the Q model parameter and root-mean-squared error prediction (RMSEP) highlights the variable influence that the nonvolatile fraction has on prediction, showing that it has a higher impact on describing acid, bitter, and woody notes than on flowery and fruity. The data fusion emphasized the aroma contribution to driving sensory perceptions, although the correlative networks highlighted from the volatile and nonvolatile data deserve a thorough investigation to verify the potential of odor-taste integration.

Multisensory interactions underlying flavor consumption in rats: the role of experience and unisensory component liking

The mechanisms by which taste and odor are combined in determining food choice behavior are poorly understood. Previous work in human subjects has yielded mixed results, potentially due to differences in task context across studies, and a lack of control over flavor experience. Here, we used rats as a model system to systematically investigate the role of experience and unisensory component liking in the multisensory interactions underlying consumption behavior. We demonstrate that taste–smell mixture consumption is best explained by a linear average of component liking. The observed pattern of results was not dependent on prior experience with specific taste–smell combinations, and unique for multisensory as opposed to unisensory mixture consumption. The results are discussed with respect to existing models of flavor integration, and a maximum-likelihood integration model previously described for multisensory judgments in other systems.

Prediction of Fruity Aroma Intensity and Defect Presence in Virgin Olive Oil Using an Electronic Nose

The organoleptic profile of a Virgin Olive Oil is a key quality parameter that is currently obtained by human sensory panels. The development of an instrumental technique capable of providing information about this profile quickly and online is of great interest. This work employed a general purpose e-nose, in lab conditions, to predict the level of fruity aroma and the presence of defects in Virgin Olive Oils. The raw data provided by the e-nose were used to extract a set of features that fed a regressor to predict the level of fruity aroma and a classifier to detect the presence of defects. The results obtained were a mean validation error of 0.5 units for the prediction of fruity aroma using lasso regression; and 88% accuracy for the defect detection using logistic regression. Finally, the identification of two out of ten specific sensors of the e-nose that can provide successful results paves the way to the design of low-cost specific electronic noses for this application.