Do facial reactions add new dimensions to measuring sensory responses to basic tastes?

Basic taste solutions induce sensory perceptions via taste receptors and give rise to specific facial reactions. Many of these have been shown to be innate. The aim of this study was to explore relationships between the sensory perception of basic taste solutions at different concentrations and facial reactions.Basic taste solutions each at three levels plus water were served to a panel. The assessors individually identified quality, intensity and pleasantness. They were recorded during tasting and their facial reactions (based on FACS) were coded and analysed.Facial reactions indicated both quality and concentration of the stimuli. The intensity of most facial reactions increased with increasing stimulus concentration, most pronounced for sourness (lips) and bitterness (eyes and forehead). Pleasantness ratings decreased with increasing concentrations of all basic tastes. Water and the lowest sucrose concentration were perceived as the most pleasant samples and gave rise to the lowest intensity of facial reactions. The study showed that a combination of sensory analyses and facial expressions was successful in adding further insight to the knowledge of perception of basic tastes.     

PERCEIVED TEXTURAL DIMENSIONS OF FRUIT-BASED BEVERAGES

The major sensory dimensions of the mouthfeel of fruit based beverages were determined by principal components analysis and the degree of correlation between mouthfeel characteristics and the taste and pleasantness of beverages was assessed. Untrained college students rated 35 different beverages on 16 different 10-point scales containing mouthfeel, taste and hedonic terms. Two major mouthfeel dimensions emerged with this set of beverages and they were termed density/thickness and chemical irritant effect. An interdependence between mouthfeel and taste ratings was also found. Sweetness ratings were negatively correlated and sour, salty and bitter tastes were positively correlated with mouthfeel terms describing oral mucosal irritation.     

The role of sour and bitter perception in liking,familiarity and choice for phenol-rich plant-based foods

Among factors influencing food preferences and choices, individual differences in taste perception play a key role in defining eating behaviour. In particular, sour and bitter responsiveness could be associated with the acceptance and the consumption of phenol-rich plant-based foods recommended for a healthy diet. The aim of this study was to investigate, in a large population sample, the associations among sour and bitter responsiveness and liking, familiarity and choice for plant-based foods characterized by these target tastes. Adults aged 18 to 60 years (n = 1198; 58% women) were tested for their sour and bitter responsiveness both in water solutions and in food models (pear juice-based beverages modified in citric acid content to induce different levels of sourness: 0.5, 2.0, 4.0 and 8.0 g/kg; chocolate pudding samples modified in sucrose content to induce different levels of bitterness: 38, 83, 119, 233 g/kg). Familiarity, stated liking and choice for fruit juices and vegetables varying for sour/bitter taste (high in bitter/sour taste: e.g. grapefruit juice and cauliflower; low in bitter/sour taste: e.g. zucchini and pineapple juice) were measured. Results showed a significant positive correlation between bitter and sour taste perception in water solutions and model foods, as well as a positive correlation between the perceived intensity of the two taste stimuli. Subjects characterized by high responsiveness to the two target stimuli were found to give lower liking scores to foods characterized by sour/bitter tastes and tended to choose less sour/bitter foods compared to less responsive subjects.Thus, food choice for phenol rich plant-based products could be associated with a reduced responsiveness to bitter and sour tastes and a consequent higher acceptance of food products characterized by these taste qualities.     

Learned color taste associations in a repeated brief exposure paradigm

Individuals can learn to associate tastes with odors through repeated exposure. We adapted this paradigm, testing whether individuals can learn to associate tastes with colors, and whether these learned color-taste associations generalize to unconditioned, but qualitatively similar stimuli. Experiment 1 tested if individuals could learn color-taste associations for prototypical tastes, while Experiment 2 tested if individuals could learn to discriminate specific bitter compounds using color-taste associations. Conditioned stimuli in Experiment 1 consisted of solutions representing four different prototypical taste qualities. Conditioned stimuli in Experiment 2 consisted of three different bitter stimuli and a sucrose control. Both experiments consisted of six laboratory visits. On day 1, participants rated intensities of conditioned and unconditioned stimuli. On days 2–5 participants completed triangle tests, where a color was systematically paired with high/low intensity combinations of the conditioned stimuli. On day 6, participants matched colorless solutions containing the conditioned and unconditioned stimuli to one of four colors in a forced choice task. In Experiment 1, group performance was significantly above chance (25%) when matching the conditioned taste stimulus to the previously paired color. Also, learning generalized to unconditioned stimuli with a similar taste quality. In Experiment 2, group performance versus chance (25%) indicated participants learned associated sweetness with the previously paired color, both for sucrose (conditioned stimulus) and aspartame (unconditioned stimulus). However, matching performance did not exceed chance for the three different bitterants. These data suggest that particular color-taste associations can be learned with repeated exposure, even when the exposure period is relatively brief.     

Functional properties of soy sauce and metabolism genes of strains for fermentation

Soy sauce is considered the most important food condiment in China for its distinct fragrance and salty taste. Highly valued for its unique tastes and flavours, soy sauce exhibits many beneficial functions, such as 4‐hydroxy‐2(or 5)‐ethyl‐5(or 2)‐methyl‐3(2H)‐furanone and 4‐ethylguaiacol. Soy sauce has been widely used in Asian countries for cooking. With the rapidly growing popularity of these unique tastes and flavours, it is important to have a comprehensive reference of its functional benefits. Meanwhile, the genes encoding the major enzymes of metabolism exhibit specialised roles. This review provides a valuable source for the abundant metabolism genes of strains and current knowledge on antioxidant activity, antihypertensive effect, anticarcinogenic activity, fortification and their relationships with soy sauce tastes and flavours.     

Price information influences the subjective experience of wine: A framed field experiment

Past experimental laboratory and correlational data from observational research has shown that knowledge of the price of wine influences the consumer’s subjective experience. However, there is limited prior research that has explicitly manipulated price information in a realistic wine tasting setting. A total of 140 participants tasted three different low-, mid- and high-priced wines with open, deceptive, or no price information and rated them for taste intensity and pleasantness. In our community sample, intensity of taste ratings for open, deceptive and blind price information reflected retail prices, thus more expensive wines were rated as more intense in taste. However, while pleasantness ratings did not differ for open and no price information, deceptive up-pricing of low-price wine significantly influenced ratings for pleasantness, whereas deceptive down-pricing of high-price wine had no effect on pleasantness ratings. Thus, pricing information differentially influences the consumer’s subjective experience of wine, with no effects on intensity of taste ratings and no effects on pleasantness ratings with correct or no price information, but increased pleasantness of low-price wine when provided with a deceptive higher price. Thus, in wine may lay the truth, but its subjective experience may also lie in the price.     

Is the taste of British milk chocolate different?

The flavour of a piece of chocolate can be affected by the type and amount of ingredients present, as well as by the processing techniques used. This article reviews the factors that alter the taste of milk chocolate and considers whether a unique British flavour exists. Chocolate varieties with a wide range of flavours are currently being sold throughout the world and most are available within the UK. It is concluded that the existence of a unique British milk chocolate flavour may be due to the widespread use of chocolate crumb as an ingredient, which introduces a cooked taste into the final product.     

Direct mapping of affective pictures and taste words

Affective pictures have been shown to influence taste perceptions under various experimental paradigms. How are affective visual inputs associated with different tastes? More specifically, are there associations between different types of affective pictures and taste words? Here, we undertook a systematic study aimed at delineating the relationship between affective pictures and taste words. Pictures from the Chinese Affective Picture System (CAPS) and other online websites were selected, evaluated and reorganized according to the participants' hedonic and arousal ratings. The pictures were then divided into positive, neutral and negative groups according to their hedonic ratings. Each affective group was subdivided into mild, medium and strong sensations according to the arousal ratings. During the experiments, the participants were shown the pictures and were instructed to choose one of the four taste words (sour/sweet/bitter/salty) as an immediate response. The results showed that positive affective pictures were significantly associated with the word sweet. When the arousal of the positive pictures increased, the choice ratio of “sweet” increased. Negative pictures, with low to medium arousal, were significantly associated with “sour”. Negative and neutral pictures, with strong arousal, were significantly associated with “bitter”. Neutral pictures, with mild to medium arousal, were not significantly associated with any taste word.     

Hedonic mediation of the crossmodal correspondence between taste and shape

Crossmodal correspondences between gustatory (taste), olfactory (smell), and flavour stimuli on the one hand and visual attributes on the other have been extensively documented in recent years. For instance, people have been shown to consistently match specific tastes and flavours to particular visual shapes. That said, further research is still needed in order to clarify how and why such correspondences exist. Here, we report a series of four experiments designed to assess what drives people’s matching of visual roundness/angularity to both ‘basic’ taste names and actual tastants. In Experiment 1, crossmodal correspondences between taste names and abstract shapes were assessed. Next, the results were replicated in a larger online study (Experiment 2). Experiment 3 assessed the role of liking in the association between taste words and morphed shapes along the roundness/angularity dimension. In Experiment 4, basic tastants were mapped to the roundness/angularity dimension, while the mediating role of liking for each taste was assessed. Across the 4 experiments, participants consistently matched sweetness to roundness. What is more, people’s liking for a taste (but not their liking for imagined tastes) appeared to influence their shape matching responses. These results are discussed in terms of crossmodal correspondences, and a potential role for hedonics is outlined.     

The effect of viscosity and volume on pleasantness and satiating power of rice milk

The present study examined the influence of two viscosity levels (62.3 and 3.2 mPa s relative) either matched for taste or non-adjusted, and two volumes (500 and 250 ml) in a rice milk beverage on satiety and pleasantness. The separate viscosity treatments were isocaloric. Seventy-one participants consumed one of the samples in a fasted state between the hours of 8:30–9:30 a.m. Participants rated thirst and hunger prior to consumption, and then thirst, hunger, overall pleasantness, pleasantness of taste, and pleasantness of viscosity immediately post-consumption. The time to consumption of lunch was measured using food diaries. This procedure was repeated for five consecutive days. Significantly greater reductions of hunger, and longer times to lunch were observed with the 500 ml treatments, but not with the thickened treatments. Results indicate that the volume of a rice milk beverage consumed in place of a breakfast has more satiating effect than the viscosity. Moreover, a change in overall pleasantness ratings, and pleasantness of taste ratings over time was found, demonstrating the importance of repeat testing for hedonic ratings of novel foods.     

The associations between genetics,salt taste perception and salt intake in young adults

Food liking is one of the main determinants of food intake. Salt taste perception and preference, that play a role in liking of salt, may be genetically determined, although research in humans is scarce. The aim of this study was to explore the associations between genetics, salt taste perception, preference, self-reported salt habit and intake. The participants were young (18–35 years) and healthy adults (32 males and 63 females). Salt taste thresholds were determined with British Standard ISO3972:2011 methodology and salt taste preference by ratings of saltiness and pleasantness of tomato soup with salt concentrations reflecting salt content in foods. Self-reported salt habit was determined by asking participants how salty they usually eat their food and salt intake with two 24-hour 5-step multiple pass recalls. Genotyping for variants in the SCNN1B rs239345 and TRPV1 rs8065080 was performed. Participants homozygous for the minor allele of the rs8065080 had lower ratings of saltiness (p = 0.008) and higher ratings of pleasantness of soup (p = 0.027) when compared to major allele carriers. Preference for salt in soup was associated with salt habit (p = 0.003) and participants with high salt preference had higher salt intake compared to those with low salt preference (2236 ± 261 vs. 1543 ± 107 mg/1000 kcal, p = 0.017). TRPV1 rs8065080 may play a role in salt taste perception and preference, which should be confirmed in a larger sample size study. Hedonic appeal of salty food should be considered when providing personalised advice to change this behaviour.     

Changes in flavour,emotion, and electrophysiological measurements when consuming chocolate ice cream in different eating environments

The eating context influences eating behaviour as well as the hedonic response to food. This study investigated temporal changes in the perceived flavour of chocolate ice cream when consumed in a laboratory, café, university study area, and a city bus stop, and further examined how emotion and electrophysiological measures were influenced by these environments. In this study, three measures were obtained from 160 participants. First, temporal changes in multisensory flavour perception after consuming chocolate ice cream in different environments were determined using the Temporal Dominance of Sensations (TDS) method. Second, participants’ emotional responses were measured after consuming ice cream using a check-all-that-apply (CATA) list of emotions. Finally, standard electrophysiological measures of heart rate (HR), blood volume pulse (BVP), and skin conductance (SC) were also obtained. When ice cream was consumed in the café, it was associated with positive emotions and a sweet taste/flavour. When consumed in the university study area, it was correlated with both positive and negative emotions, and cocoa and milky flavours. Consumption at the city bus stop was correlated with the most negative emotions, and with roasted and bitter tastes/flavours. The laboratory environment was only correlated with the attributes of ‘concentrating’ and creamy flavour. SC was significantly increased in the university study area as compared to the laboratory, and HR was significantly decreased in the university study area environment as compared to the bus stop. The evidence from this study therefore indicates that the eating context constitutes an important factor to consider when carrying out sensory testing as participants’ emotions, perceptions, and electrophysiological responses are influenced differently dependent upon the eating context.     

What reported food-evoked emotions may add: A model to predict consumer food choice

Food-evoked emotions provide information that goes beyond the information from traditional hedonic ratings. The objectives of our study were: (i) to investigate how intrinsic (sensory) and extrinsic (packaging) cues affect consumers’ emotional responses to foods, and (ii) to explore whether emotional responses to these cues combined with liking, predict actual food choice. Participants (n = 103) rated emotional responses to seven products under a blind taste, a package and a package and taste condition using the EsSense Profile™. During the blind taste condition participants also scored liking of the products. Test products were breakfast drinks and desserts. Food choice was measured in two different breakfast sessions reflecting a different choice context. In one choice context, products were presented blind to taste, after which participants chose one out of the seven foods to consume for breakfast. In the other choice context, participants based their choice on the package of the seven foods without tasting them. Results showed that emotions evoked by food products could be organised in a two-dimensional space, representing a valence (pleasantness) and an activation/arousal dimension. Specific emotional profiles generated for products differed across the blind taste, package and the package and taste condition, meaning that intrinsic and extrinsic product properties elicit in part different emotions. Liking and valence together had the strongest predictive value for product choice based on the product’s taste. The combination of liking, valence and arousal had the strongest predictive value for package-based choice. In conclusion, food-evoked emotions add predictive value to solely liking ratings, and may guide consumers’ product choice behaviour.     

Sandwiches and milk with varying fat and sodium contents: What is the best combination?

Saltiness and fattiness were systematically varied in combinations of wheat bread (unsalted vs regular-salt), spread (none vs regular-salt and regular-fat), cheese (low-salt and low-fat vs low-fat). All possible combinations, amounting to sixteen samples of sandwich and milk, were presented to 43 subjects for ratings of pleasantness. The subjects also rated the pleasantness of individual components. The unsalted bread without spread but with low-salt, low-fat cheese and any of the milk types received the lowest hedonic ratings, whereas the regular-salt bread with spread and with any of the cheese and milk options received the highest. The pleasantness of individual components predicted the pleasantness of a combination by only 10–40% (multiple regression analysis). Thus the pleasantness of an entity depended on the pleasantness of components only to a very limited extent. The absence of major elements, such as spread on bread or the salty taste in bread, had major effects on acceptance.     

Temporal aspects of hedonic and intensity responses

The present study investigated temporal aspects of hedonic responses. The focus was on the hedonic response in itself and on the time-course of the hedonic response as compared to the intensity response. Analogously to time–intensity (TI) scaling, we used temporal scaling for intensity and pleasantness aspects of taste. Twenty four subjects were instructed to focus on and continually rate either the intensity or the pleasantness of three different concentrations of an orange lemonade stimulus in a within-participants design. As was expected, the latency and the time to maximum of the intensity response were shorter than the latency and time to maximum of the hedonic response. Unforeseen, the intensity response lasted longer than the pleasantness response. These results suggest that initially the processing of the intensity and pleasantness aspects is in serial and later on may be in parallel. Our study confirms that, as was suggested by Taylor and Pangborn [Journal of Sensory Studies 4 (1990) 241–247], time–hedonic scaling can be performed.