How Individual Variations in the Perception of Basic Tastes and Astringency Relate with Dietary Intake and Preferences for Fruits and Vegetables

Background: Oral food perception plays a major role in food acceptance, although the way it relates with food preferences and final choices in adults is still debatable. The objective of the present study was to assess the relationship between gustatory function, dietary habits and fruit and vegetable preferences. Methods: Recognition thresholds, suprathreshold and hedonics were accessed for sweet, bitter, sour, salty and astringency in 291 adult participants. A Food Frequency Questionnaire (FFQ) and a questionnaire for assessment of preferences for individual fruit and vegetables were filled by the participants. Results: Three clusters were obtained: “most sensitive”, “less sensitive” and “less sensitive only for sour”. The less sensitive cluster showed lower preferences for fruit and vegetables and higher intake of sweets and fast foods, whereas higher preferences for sweet veggies were observed in the “most sensitive” cluster. Basic tastes and astringency hedonics did not associate with fruit and vegetable preferences, but the sensitivity for these oral sensations did. Conclusions: Taste and astringency sensitivities are related with the preference for fruit and vegetables, being also associated with some dietary habits. The effectiveness of the strategies to promote plant-based healthy food consumption may benefit from the knowledge of individuals’ gustatory function.

Developmental Changes in Food Perception and Preference

Food choices are a key determinant of dietary intake, with involved brain regions such as the mesolimbic and prefrontal cortex maturing at a differential rate from childhood to young adulthood. However, developmental changes in healthy and unhealthy food perception and preference remain poorly understood. We aimed to understand this gap by investigating whether perceptions and preferences for food vary as a function of age, and how specific food attributes (i.e., taste and health) impact these age-related changes. We hypothesized that there would be an inverted U-shaped relationship between age and preference for high-calorie foods. As well, we expected that both dietary self-control and the decision weight of the health attribute would increase with age. One hundred thirty-nine participants aged 8–23 years (79 males, 60 females) participated in this study. They completed computerized rating tasks to assess taste, health, and liking (or preference) of high-calorie and low-calorie foods, followed by 100 binary food choices based on each participant’s individual ratings for taste and health. Among the 100 pairs, 75 were deemed challenge trials, where one food had a higher taste rating but a lower health rating than the other food item. Dietary self-control was considered successful when the healthier food cue in the challenge trial was chosen, and self-control success ratio (SCSR) was computed as the proportion of self-control success trials over the total number of choices. Results showed that high-calorie foods were rated as more tasty (r = 0.32, p < 0.001) and less healthy (r = -0.22, p < 0.01) with increasing age. As well, older participants wanted to eat high-calorie foods more than the younger participants (r = 0.29, p = 0.001). Furthermore, older age was associated with an increased decision weight of taste attribute on food preferences (r = 0.26, p = 0.002), suggesting that the taste attribute may contribute to the age-related increases in preference for high-calorie foods. Although participants rated low-calorie foods as less tasty (r = -0.17, p = 0.04) and less healthy (r= -0.31, p < 0.001) with increasing age, there was no significant association between age and preference for low-calorie foods. Participants made faster food choices with increasing age (r= -0.31, p < 0.001), which was driven by failed self-control choices (r = -0.23, p = 0.006). There was no significant association between age and SCSR (p = 0.5). Our results are consistent with other studies that demonstrate age-related increases in consumption of calorie-dense foods in youth, and suggest that age may be more relevant to preference for high-calorie than low-calorie foods. Future studies are merited to investigate the neurobiology underlying these developmental changes in food perceptions and preferences.

Serotonin and dopamine modulate aging in response to food perception and availability

An organism’s ability to perceive and respond to changes in its environment is crucial for its health and survival. Here we reveal how the most well-studied longevity intervention, dietary restriction (DR), acts in-part through a cell non-autonomous signaling pathway that is inhibited by the perception of attractive smells. Using an intestinal reporter for a key gene induced by DR but suppressed by attractive smells, we identify three compounds that block food perception in C. elegans, thereby increasing longevity as DR mimetics. These compounds clearly implicate serotonin and dopamine in limiting lifespan in response to food perception. We further identify an enteric neuron in this pathway that signals through the serotonin receptor 5-HT1A/ser-4 and dopamine receptor DRD2/dop-3. Aspects of this pathway are conserved in D. melanogaster and mammalian cells. Thus, blocking food perception through antagonism of serotonin or dopamine receptors is a plausible approach to mimic the benefits of dietary restriction.

An instrument for measuring the influence of consumers' cultural values on functional food perception

PurposeThe purpose of the article is to develop an instrument for measuring the influence of consumers' cultural values on functional food perception.Design/methodology/approachThe study is quantitative in nature and builds on an earlier qualitative study that employed in-depth interviews, thematic analysis and constant comparative analysis to construct a survey instrument which initially had 53 items. The quantitative study involved an online survey that was conducted using this instrument, which resulted in 365 complete cases that included 173 Anglo-Australian, 102 Chinese and 90 Indian respondents living in Australia. The survey data were subjected to exploratory factor analysis using Principal axis factoring, with Promax rotation.FindingsThe research has validated that functional food perception is dependent upon consumers' cultural values. The results of the exploratory factor analysis provided a six-factor instrument with 32 items.Research limitations/implicationsOnly three ethnic groups were involved in this study and that is not entirely representative of Australia or other countries. The instrument, however, will allow researchers in the field of functional food to extend the research to other diverse communities.Practical implicationsThe instrument will further enable functional food producers and marketers to develop effective marketing strategies based on their knowledge of the influence of cultural values on functional food perception.Originality/valueThe instrument developed from this study, for measuring consumers' functional food perception based on cultural values, is the first of its kind.

Visual attention towards food during unplanned purchases – A pilot study using mobile eye tracking technology

This pilot study aims to investigate the relationships between consumers’ weight status, energy density of food and visual attention towards food during unplanned purchase behavior in a real-world environment. After more than a decade of intensive experimental eye tracking research on food perception, this pilot study attempts to link experimental and field research in this area. Shopping trips of participants with different weight status were recorded with mobile eye tracking devices and their unplanned purchase behavior was identified and analyzed. Different eye movement measurements for initial orientation and maintained attention were analyzed. Differences in visual attention caused by energy density of food were found. There was a tendency across all participants to look at low energy density food longer and more often.