Flavor Stimuli Research Articles

The color-flavor incongruency effect elicited by flavor stimuli and words

Previous research has shown that consumers associate specific packaging colors with flavors to generate the color-flavor associations for packaging. Previous studies have also demonstrated that people search more slowly for a product when its color is incongruent with its flavor label than when it is congruent with this flavor, indicative of a packaging color-flavor incongruency effect. Here we report a behavioral study designed to investigate whether actual flavor stimuli can also elicit this effect, and if so, how the effect differs when flavor cues are presented as flavor words versus flavor stimuli. Participants were asked to search for a beverage product labeled with a specific flavor after either tasting flavor stimuli or viewing a flavor word. The results showed that the participants responded faster and more accurately when they were cued by flavor words than flavor stimuli. Moreover, we also found that both flavor stimuli and flavor words could elicit the packaging color-flavor incongruency effect, and the effect elicited by flavor stimuli was greater than that elicited by flavor words. The findings of the present study provide empirical evidence of the crossmodal influence of flavor information on visual search, and also have direct implications for using sensory marketing strategies to enhance consumers’ product search efficiency.

Chemosensory continuity from prenatal to postnatal life in humans: A systematic review and meta-analysis.

Throughout pregnancy, fetuses are exposed to a range of chemosensory inputs influencing their postnatal behaviors. Such prenatal exposure provides the fetus with continuous sensory information to adapt to the environment they face once born. This study aimed to assess the chemosensory continuity through a systematic review and meta-analysis of existing evidence on chemosensory continuity from prenatal to first postnatal year. Web of Science Core. Collections, MEDLINE, PsycINFO, EBSCOhost ebook collection was searched from 1900 to 2021. Studies identified from the search were grouped according to type of stimuli the fetuses were exposed to prenatally that the neonatal infants' responses to were being evaluated, namely flavors transferred from the maternal diet, and the odor of their own amniotic fluid. Of the 12 studies that met the eligibility criteria for inclusion (k = 6, k = 6, respectively in the first and the second group of studies), and eight studies (k = 4, k = 4, respectively) provided sufficient data suitable for meta-analysis. Infants, during their first year of life, oriented their heads for significantly longer durations in the direction of the prenatally experienced stimuli with large pooled effect sizes (flavor stimuli, d = 1.24, 95% CI [0.56, 1.91]; amniotic fluid odor, d = 0.853; 95% CI [.632, 1.073]). The pooled effect size for the duration of mouthing behavior was significant in response to prenatal flavor exposure through maternal diet (d = 0.72; 95% CI [0.306, 1.136]), but not for the frequency of negative facial expressions (d = -0.87, 95% CI [-2.39, 0.66]). Postnatal evidence suggests that there is a chemosensory continuity from fetal to the first year of postnatal life.

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.

A new paradigm for investigating temporal order memory shows higher order associations are present in recent but not in remote retrieval.

Memory of a sequence of distinct events requires encoding the temporal order as well as the intervals that separates these events. In this study, using order-place association task where the animal learns to associate the location of the food pellet to the order of entry into the event arena, we probe the nature of temporal order memory in mice. In our task, individual trials become distinct events, as the animal is trained to form a unique association between entry order and a correct location. The inter-trial intervals (> 30min) are chosen deliberately to minimize the inputs from working memory. We develop this paradigm initially using four order-place associates and later extend it to five paired associates. Our results show that animals not only acquire these explicit (entry order to place) associations but also higher order associations that can only be inferred implicitly (temporal relation between the events) from the temporal order of these events. As an indicator of such higher order learning during the probe trial, the mice exhibit predominantly prospective errors that decline proportionally with temporal distance. On the other hand, prior to acquiring the sequence, the retrospective errors are dominant. In addition, we also tested the nature of such acquisitions when temporal order CS is presented along with flavored pellet as a compound stimulus comprising of order and flavor both simultaneously being paired with location. Results from these experiments indicate that the animal learns both order-place and flavor-place associations. Comparing with pure order-place training, we find that the additional flavor stimulus in a compound training paradigm did not interfere with the ability of the animals to acquire the order-place associations. When tested remotely, pure order-place associations could be retrieved only after a reminder training. Further higher order associations representing the temporal relationship between the events is markedly absent in the remote time.

Dynamic sensations of fresh and roasted salmon (Salmo salar) during chewing

The sensory perception of food is a dynamic procedure, which is closely related to the released flavor stimuli. Thus, we evaluated the dynamic sensations of fresh and roasted salmon during the chewing process and investigated the tastants released in saliva. For fresh salmon, the fishy, umami, salty, and sweet attributes were perceived successively. Meanwhile, the smoky and fried flavors were the most dominant attributes of roasted salmon at the beginning, then various attributes were perceived. During the chewing process, free amino acids and 5′-nucleotides released in saliva were quantified. Compared to the sensory data, the results demonstrated that glutamic acid and inosine 5′-monophosphate released in saliva might induce the umami perception. The sweet-tasting amino acids alanine and glycine may contribute to sweetness. Therefore, we suggested that the time dimension of tastants dissolved in saliva would affect the dynamic sensation of food, even for complex food materials.

Multisensory Flavour Perception: Blending, Mixing, Fusion, and Pairing Within and Between the Senses.

This review summarizes the various outcomes that may occur when two or more elements are paired in the context of flavour perception. In the first part, I review the literature concerning what happens when flavours, ingredients, and/or culinary techniques are deliberately combined in a dish, drink, or food product. Sometimes the result is fusion but, if one is not careful, the result can equally well be confusion instead. In fact, blending, mixing, fusion, and flavour pairing all provide relevant examples of how the elements in a carefully-crafted multi-element tasting experience may be combined. While the aim is sometimes to obscure the relative contributions of the various elements to the mix (as in the case of blending), at other times, consumers/tasters are explicitly encouraged to contemplate/perceive the nature of the relationship between the contributing elements instead (e.g., as in the case of flavour pairing). There has been a noticeable surge in both popular and commercial interest in fusion foods and flavour pairing in recent years, and various of the ‘rules’ that have been put forward to help explain the successful combination of the elements in such food and/or beverage experiences are discussed. In the second part of the review, I examine the pairing of flavour stimuli with music/soundscapes, in the emerging field of ‘sonic seasoning’. I suggest that the various perceptual pairing principles/outcomes identified when flavours are paired deliberately can also be meaningfully extended to provide a coherent framework when it comes to categorizing the ways in which what we hear can influence our flavour experiences, both in terms of the sensory-discriminative and hedonic response.

Evidence that novel flavors unconditionally suppress weight gain in the absence of flavor-calorie associations.

Beginning with Pavlov (1927), there has been great interest in how associative learning processes affect eating behavior. For instance, flavors can become preferred when paired with calories or, conversely, become aversive when paired with illness. This relationship between flavors and caloric or toxic outcomes has been investigated by a number of theorists. We studied the effect of daily consumption of a flavor that was either paired or unpaired with calories provided by sugar on body weight change and daily food consumption over a 21-day period. Over three experiments, we observed an unanticipated attenuation of weight gain following consumption of flavored liquid solutions, particularly when those solutions were non-caloric. However, we did not find any impact of consuming the flavored liquid solutions on appetite. Given differences in weight gain in the absence of differences in the amount of food consumed, we suggest that unconditioned metabolic responses are elicited to initially novel flavor stimuli, even if those flavors are not followed by caloric outcomes. Potential dieting interventions based on these findings are discussed as is how they inform our understanding of the balance between unconditioned and conditioned responses.

The potential for retronasally delivered olfactory stimuli to assess psychiatric conditions

Recent research has linked the ability to identify odours to parts of the brain that, when impaired, are associated with mental illness or disease. The link between impaired odour perception and some psychological disorders has led to the suggestion that standardised assessments probing smell be routinely adopted in the clinical environment. Odour tests currently on the market utilise the orthonasal route, though the retronasal route is a viable, but overlooked, alternative. In this study, a flavour delivery system has been developed which quickly dissolves in the buccal cavity, rapidly releasing flavours that reach the olfactory system by the retronasal route. We tested seven different types of retronasal flavour stimuli (peppermint, aniseed, liquorice, coffee, orange, lemon, and valeric acid) on 171 undergraduate and postgraduate university students and related perceptual measures with psychological wellbeing scores. Olfactory measures included odour identification, pleasantness, intensity, and familiarity. Psychological measures of schizotypy (SPQ-B), depression, stress and anxiety (DASS-21), and autism spectrum disorder (RAADS-R) were obtained to represent psychological wellbeing. A battery of hierarchical multiple linear regressions were run to determine the relationships between odour perception and the psychometric measures. After controlling for age and gender, significant negative associations were found between odour identification and the stress (β = −.347, p < .001), anxiety (β = −.376, p < .001), depression (β = −.318, p < .001), schizotypy (β = −.473, p < .001), and RAADS-R (β = −.285, p < .001) scales. Additionally, both overall pleasantness (β = −.203, p < .01) and intensity (β = .194, p < .05) ratings were negatively correlated to the RAADS-R. Our findings indicate that retronasal stimuli present a feasible alternative to olfactory assessment of psychological states and further reinforces evidence indicating a correlation between olfactory and psychological measures.

Chapter 7 - Taste and smell processing in the brain

Taste pathways in humans and other primates project from the nucleus of the solitary tract directly to the taste thalamus, and then to the taste insula. The taste cortex in the anterior insula provides separate and combined representations of the taste, temperature, and texture of food in the mouth independently of hunger and thus of reward value and pleasantness. One synapse on, in the orbitofrontal cortex, these sensory inputs are for some neurons combined by associative learning with olfactory inputs received from the pyriform cortex, and visual inputs from the temporal lobe, and these neurons encode food reward value in that they only respond to food when hungry, and in that activations correlate linearly with subjective pleasantness. Cognitive factors, including word-level descriptions, and selective attention to affective value, modulate the representation of the reward value of taste, olfactory and flavor stimuli in the orbitofrontal cortex and a region to which it projects, the anterior cingulate cortex. These food reward representations are important in the control of appetite, and the liking of food. Individual differences in these reward representations may contribute to obesity, and there are age-related differences in these reward representations.

Retronasal Habituation: Characterization and Impact on Flavor Perception Using Time-Intensity

Olfactory habituation results from prolonged exposure to an odor, leading to perceptual changes defined by several characteristics. To date, human habituation research has focused on orthonasal olfaction which is perceived externally while ignoring internal routes of odor perception related to flavor. In our study, we conducted two experiments to characterize retronasal olfactory habituation and measured its impact on flavor perception. In Experiment 1, participants were presented a food odor and non-food odor retronasally, using an orally adhered strip. Each participant rated the odor intensity using a time-intensity procedure. After exposure, the participants ate a lime-flavored gummy and rated the lime flavor. In experiment 2, the same procedure was performed for a low-level lime odor, a simple (lime oil) and complex (lime oil + sucrose + citric acid) beverage as the flavor stimuli. Our results demonstrated two known principles of habituation for retronasally presented odors: (1) prolonged exposure leads to decreased perception and (2) weaker stimuli lead to more rapid habituation. Additionally, we found that the non-food odor habituated slower than the food odor; however, the participants seemed to recover simultaneously upon food and beverage consumption leading to no change in flavor perception. The findings of this study give evidence that we habituate to different odors at different rates; more specifically, we provide evidence that differentiates between odor origin and concentration. This is the first time-intensity characterization of retronasal odor habituation. Additionally, a novel method of administering retronasal odors is presented.

Crossmodal contributions to the perception of piquancy/spiciness

AbstractThe last 500 years or so has seen a phenomenal increase of interest in piquant/spicy food around the world. In this review, the latest research documenting the crossmodal influences on the perception of oral piquancy/spiciness that have been established to date are summarized: Everything from the color of the foodstuff through the color of the plateware on which that food is served has been found to influence both the expected and experienced piquancy/spiciness of food. Furthermore, certain musical parameters have also been shown to enhance the perceived piquancy of the food in a restaurant setting. By contrast, spicy smells have not, as yet, attracted anything like as much research interest from the scientific community. Intriguingly, many of the crossmodal influences on piquancy/spiciness that have been documented to date appear to be more pronounced when the actual experience on tasting the food is close to the preconsumption expectations. And while many of the crossmodal effects in this area appear to mirror those found previously for basic taste and flavor stimuli, there is a sense in which the broader range of intensities of sensation experienced in relation to chili/capsaicin may mean that crossmodal influences are somewhat different in this case.Practical applicationsPiquancy/spiciness is a highly desirable food attribute. In fact, chiles are eaten by one in four of us every day. As yet, however, it has not attracted anything like the research interest that the basic tastes have. This review draws attention to the multisensory factors (including color, sound, etc.) that have recently been shown to modulate the experienced piquancy/spiciness of a dish. Given its widespread appeal, gaining a better understanding of this most desirable of oral sensations is likely to benefit food providers.

Differences in BOLD responses in brain reward network reflect the tendency to assimilate a surprising flavor stimulus to an expected stimulus

External information can modify the subjective value of a tasted stimulus, but little is known about neural mechanisms underlying these behavioral modifications. This study used flavored drinks to produce variable degrees of discrepancy between expected and received flavor. During a learning session, 43 healthy young men learned 4 symbol-flavor associations. In a separate session, associations were presented again during an fMRI scan, but half of the trials introduced discrepancy with previously learned associations. Liking ratings of drinks were collected and were analyzed using a linear model to define the degree to which discrepant symbols affected liking ratings of the subjects during the fMRI session. Based on these results, a GLM analysis of fMRI data was conducted to determine neural correlates of observed behavior. Groups of subjects were composed based on their behavior in response to discrepant symbols, and comparison of brain activity between groups showed that activation in the PCC and the caudate nucleus was more potent in those subjects in which liking was not affected by discrepant symbols. These activations were not found in subjects who assimilated unexpected flavors to flavors preceeded by discrepant symbols. Instead, these subjects showed differences in the activity in the parietal operculum. The activity of reward network appears to be related to assimilation of received flavor to expected flavor in response to symbol-flavor discrepancy.

Food oral processing in humans: links between physiological parameters, release of flavour stimuli and flavour perception of food

In humans, food oral processing (FOP) is the first step in the digestive process. It prepares the food for swallowing and to undergo the process of digestion. During chewing, the food is comminuted by the combined action of chewing and saliva to form a bolus. The particle size of the bolus is reduced due to the action of the tongue and the teeth, and the saliva is continuously produced by the salivary glands to humidify and impregnate the food. Saliva lubricates the bolus and enables the cohesion of particles to prepare for swallowing. During food oral processing, the compounds responsible for food flavour and taste are released, leading to the perception of food organoleptic properties and significantly contributing to the consumer’s acceptability of the product. Understanding this process of food breakdown and bolus formation thus appears to be a way to revisit food functional properties. However, this process is extremely complex, and as such, its description necessitates a combination of many quantities from different disciplines, i.e., physics, chemistry, physiology, psychology, behavioural science and food science. It depends, on one hand, on food properties and on the other hand, it depends on oral physiology. However, large inter-individual variability is commonly observed, which has important consequences on flavour release and perception. The challenge for the food industry is to be able to develop food considering this large variability, and sensory and nutritional constraints. This challenge is particularly relevant when specific populations (i.e., elderly, infants or obese subjects) are considered.

Food oral processing in humans: links between physiological parameters, release of flavour stimuli and flavour perception of food

In humans, food oral processing (FOP) is the first step in the digestive process. It prepares the food for swallowing and to undergo the process of digestion. During chewing, the food is comminuted by the combined action of chewing and saliva to form a bolus. The particle size of the bolus is reduced due to the action of the tongue and the teeth, and the saliva is continuously produced by the salivary glands to humidify and impregnate the food. Saliva lubricates the bolus and enables the cohesion of particles to prepare for swallowing. During food oral processing, the compounds responsible for food flavour and taste are released, leading to the perception of food organoleptic properties and significantly contributing to the consumer’s acceptability of the product. Understanding this process of food breakdown and bolus formation thus appears to be a way to revisit food functional properties. However, this process is extremely complex, and as such, its description necessitates a combination of many quantities from different disciplines, i.e., physics, chemistry, physiology, psychology, behavioural science and food science. It depends, on one hand, on food properties and on the other hand, it depends on oral physiology. However, large inter-individual variability is commonly observed, which has important consequences on flavour release and perception. The challenge for the food industry is to be able to develop food considering this large variability, and sensory and nutritional constraints. This challenge is particularly relevant when specific populations (i.e., elderly, infants or obese subjects) are considered.

Wine Flavor Perception in a Person with Isolated Congenital Aglossia, Naïve Wine Taster, and Sommelier

Objective: This study aimed to augment previous research that investigated flavor perception in isolated congenital aglossia by a whole food/beverage approach. Isolated congenital aglossia is the rare condition of absence of a tongue at birth without the presence of other symptoms. Previous studies confirmed taste perception in isolated congenital aglossia using single taste solutions including sour, salty, sweet, bitter, and umami. Methods: The current randomized, double-blinded study age- and sex-matched a naive wine taster and sommelier to the 46 year-old female with isolated congenital aglossia. A Nose and Palate Survey with 54 variables created based on the Court of Master Sommeliers Deductive Tasting Format was used to evaluate flavor perception. All of the five red wines were tested in triplicate in random order, for a total of 15 separate samples per subject. Results: There was a significant difference in overall nose ratings among the participants F(2,42)=63.461, p<0.001, with post hoc analysis revealing differences in overall nose ratings between the person with isolated congenital aglossia and sommelier (p<0.001), as well as between the naive wine taster and sommelier (p<0.001). There was a significant difference in overall palate ratings among the participants F(2,42)=48.651, p<0.001, and post hoc analysis revealed differences in overall palate ratings between the person with isolated congenital aglossia and sommelier (p<0.001), as well as between the naive wine taster and sommelier (p<0.001). There were no significant differences between the person with isolated congenital aglossia and naive wine taster with a tongue for either overall nose or palate ratings. Conclusion: These results support previous findings that individuals with isolated congenital aglossia can discern various taste and flavor stimuli and suggest that absence of tongue does not greatly affect wine flavor perception among naive wine tasters.

Single-neuron responses to intraoral delivery of odor solutions in primary olfactory and gustatory cortex.

Smell plays a major role in our perception of food. Odorants released inside the mouth during consumption are combined with taste and texture qualities of a food to guide flavor preference learning and food choice behavior. Here, we built on recent physiological findings that implicated primary sensory cortex in multisensory flavor processing. Specifically, we used extracellular recordings in awake rats to characterize responses of single neurons in primary olfactory (OC) and gustatory cortex (GC) to intraoral delivery of odor solutions and compare odor responses to taste and plain water responses. The data reveal responses to olfactory, oral somatosensory, and gustatory qualities of intraoral stimuli in both OC and GC. Moreover, modality-specific responses overlap in time, indicating temporal convergence of multisensory, flavor-related inputs. The results extend previous work suggesting a role for primary OC in mediating influences of taste on smell that characterize flavor perception and point to an integral role for GC in olfactory processing.NEW & NOTEWORTHY Food perception is inherently multisensory, taking into account taste, smell, and texture qualities. However, the neural mechanisms underlying flavor perception remain unknown. Recording neural activity directly from the rat brain while animals consume multisensory flavor stimuli, we demonstrate that information about odor, taste, and mouthfeel of food converges on primary taste and smell cortex. The results suggest that processing of naturalistic, multisensory information involves an interacting network of primary sensory areas.

Reward Systems in the Brain and Nutrition.

The taste cortex in the anterior insula provides separate and combined representations of the taste, temperature, and texture of food in the mouth independently of hunger and thus of reward value and pleasantness. One synapse on, in the orbitofrontal cortex, these sensory inputs are combined by associative learning with olfactory and visual inputs for some neurons, and these neurons encode food reward value in that they respond to food only when hunger is present and in that activations correlate linearly with subjective pleasantness. Cognitive factors, including word-level descriptions and selective attention to affective value, modulate the representation of the reward value of taste, olfactory, and flavor stimuli in the orbitofrontal cortex and a region to which it projects, the anterior cingulate cortex. These food reward representations are important in the control of appetite and food intake. Individual differences in reward representations may contribute to obesity, and there are age-related differences in these reward representations. Implications of how reward systems in the brain operate for understanding, preventing, and treating obesity are described.

Emotional susceptibility trait modulates insula responses and functional connectivity in flavor processing

The present study aimed at investigating the relationship between Emotional Susceptibility (ES), an aspect of the personality trait Neuroticism, and individual differences in the neural responses in anterior insula to primary sensory stimuli colored by affective valence, i.e., distasting or pleasantly tasting oral stimuli. In addition, it was studied whether intrinsic functional connectivity patterns of brain regions characterized by such differential responses could be related to ES. To this purpose 25 female participants underwent functional magnetic resonance imaging scanning, while being involved in a flavor experiment. During the experiment, flavor stimuli were administered consisting of small amounts of liquid with a different affective valence: neutral, pleasant, unpleasant. The results showed that individual differences in ES trait predicted distinct neural activity patterns to the different stimulus conditions in a region of left anterior insula that a previous meta-analysis revealed to be linked with olfacto-gustatory processing. Specifically, low ES was associated with enhanced neural responses to both pleasant and unpleasant stimuli, compared to neutral stimuli. By contrast, high ES participants showed equally strong neural responses to all types of stimuli without differentiating between the neutral and affective stimuli. Finally, during a task-free state, high ES trait appeared also to be related to decreased intrinsic functional connectivity between left anterior insula and left cerebellum. Our findings show that individual differences in ES are associated with differential anterior insula responses to primary sensory (flavor) stimuli as well as to intrinsic functional cortico-cerebellar connectivity, the latter suggesting a basis in the brain intrinsic functional architecture of the regulation of emotional experiences.

Progressively increasing the difficulty of a Pavlovian discrimination in a voluntary exposure to toxin paradigm with rats attenuates the magnitude of the easy-to-hard effect

Rats received two stages of Pavlovian discrimination training with two flavor stimuli: a compound consisting of saccharin mixed with 0.15M lithium chloride (LiCl), and the saccharin alone. The concentration of the saccharin solution (i.e., the common element shared by the stimuli to be discriminated) was relatively high in Stage 2 (1.2%). Groups differed in the pre-training that they received in Stage 1. Group Progressive (PROG) was pretrained in easier versions of the discrimination of Stage 2. The difficulty of these discriminations was gradually increased by progressively increasing the initial concentration of saccharin (0.15%). Group PROG learned the hardest discrimination faster than a control group (HARD) that was trained in this discrimination in both Stages 1 and 2 (Experiment 1). We also observed that the enhancement of learning observed in Group PROG was less than that observed after continuous pre-training with the easiest version of the discrimination (Group CONT; Experiment 2). We discuss the implications of these results in relation to other previous demonstrations of the easy-to-hard effect.

Superadditive opercular activation to food flavor is mediated by enhanced temporal and limbic coupling.

Food perception is characterized by a transition from initially separate sensations of the olfactory and gustatory properties of the object toward their combined sensory experience during consumption. The holistic flavor experience, which occurs as the smell and taste merge, extends beyond the mere addition of the two chemosensory modalities, being usually perceived as more object-like, intense and rewarding. To explore the cortical mechanisms which give rise to olfactory-gustatory binding during natural food consumption, brain activation during consumption of a pleasant familiar beverage was contrasted with presentation of its taste and orthonasal smell alone. Convergent activation to all presentation modes was observed in executive and chemosensory association areas. Flavor, but not orthonasal smell or taste alone, stimulated the frontal operculum, supporting previous accounts of its central role in the formation of the flavor percept. A functional dissociation was observed in the insula: the anterior portion was characterized by sensory convergence, while mid-dorsal sections activated exclusively to the combined flavor stimulus. psycho-physiological interaction analyses demonstrated increased neural coupling between the frontal operculum and the anterior insula during flavor presentation. Connectivity was also increased with the lateral entorhinal cortex, a relay to memory networks and central node for contextual modulation of olfactory processing. These findings suggest a central role of the insular cortex in the transition from mere detection of chemosensory convergence to a superadditive flavor representation. The increased connections between the frontal operculum and medial temporal memory structures during combined olfactory-gustatory stimulation point to a potential mechanism underlying the acquisition and modification of flavor preferences.