Effects of hot spices on energy intake,appetite and sensory specific desires in humans

This study investigated the effect of hot spices on energy intake and appetite. Forty participants received five meals of fixed portion sizes, served with or without five hot spices followed by a buffet. Spices were used in doses perceived as moderately hot, ensuring that the meals were palatable. Food intake (kJ), appetite and liking (before, during, after the meal and after the buffet), mood (before, after the meal and after the buffet) and desire to eat sweet, sour, fatty, salty, bitter and hot foods (after the meal and after the buffet) were measured on 9-point scales. Hot spices did not affect energy intake (p > 0.05). Desire for sweet foods was increased by chili (0.6 point, p < 0.05) whereas desire to eat salty foods was decreased by mustard (1 point, p < 0.01), suggesting that hot spices can induce changes in sensory specific desires. Liking of the meals tended to increase during the buffet when compared to the relatively constant liking of the fixed starter meals, suggesting that traditional sensory specific satiety does not play a large role in determining eating behaviour with complex meals.     

The consumer acceptance of novel vegetable-enriched bread products as a potential vehicle to increase vegetable consumption

Currently UK fruit and vegetable intakes are below recommendations. Bread is a staple food consumed by approximately 95% of adults in western countries. In addition, bread provides an ideal matrix by which functionality can be delivered to the consumer in an accepted and convenient food. Therefore, enriching bread with vegetables may be an effective strategy to increase vegetable consumption. This study evaluated bread enriched with red beetroot, carrot with coriander, red pepper with tomato or white beetroot (40 g vegetable per 100 g) compared to white control bread (0 g vegetable) for consumer acceptance. Consumers (n = 120) rated their liking of the breads overall, as well as their liking of appearance, flavour and texture using nine-point hedonic scales. Product replacement and purchase intent of the breads were rated using five-point scales. The effect of providing consumers with health information about the breads was also evaluated. There were significant differences in overall liking (P < 0.0001), as well as liking of appearance (P < 0.0001), flavour (P = 0.0002) and texture (P = 0.04), between the breads. However, the significant differences resulted from the red beetroot bread which was significantly (P < 0.05) less liked compared to control bread. There were no significant differences in overall liking between any of the other vegetable-enriched breads compared with the control bread (no vegetable inclusion). The provision of health information about the breads did not increase consumer liking of the vegetable-enriched breads. In conclusion, this study demonstrated that vegetable-enriched bread appeared to be an acceptable strategy to increase vegetable intake, however, liking depended on vegetable type.     

Sensory profiles and consumer acceptability of a range of sugar-reduced products on the UK market

Current UK intake of non-milk extrinsic sugars (NMES) is above recommendations. Reducing the sugar content of processed high sugar foods through reformulation is one option for reducing consumption of NMES at a population level. However, reformulation can alter the sensory attributes of food products and influence consumer liking. This study evaluated consumer acceptance of a selection of products that are commercially-available in the UK; these included regular and sugar-reduced baked beans, strawberry jam, milk chocolate, cola and cranberry & raspberry juice. Sweeteners were present in the reformulated chocolate (maltitol), cola (aspartame and acesulfame-K) and juice (sucralose) samples. Healthy, non-smoking consumers (n = 116; 55 men, 61 women, age: 33 ± 9 years; BMI: 25.7 ± 4.6 kg/m²) rated the products for overall liking and on liking of appearance, flavor and texture using a nine-point hedonic scale. There were significant differences between standard and reduced sugar products in consumers' overall liking and on liking of each modality (appearance, flavor and texture; all P < 0.0001). For overall liking, only the regular beans and cola were significantly more liked than their reformulated counterparts (P < 0.0001). Cluster analysis identified three consumer clusters that were representative of different patterns of consumer liking. For the largest cluster (cluster 3: 45%), there was a significant difference in mean liking scores across all products, except jam. Differences in liking were predominantly driven by sweet taste in 2 out of 3 clusters. The current research has demonstrated that a high proportion of consumers prefer conventional products over sugar-reduced products across a wide range of product types (45%) or across selected products (27%), when tasted unbranded, and so there is room for further optimization of commercial reduced sugar products that were evaluated in the current study. Future work should evaluate strategies to facilitate compliance to dietary recommendations on NMES and free sugars, such as the impact of sugar-reduced food exposure on their acceptance.     

Relating dynamic perception of reformulated cheese pies to consumers' expectations of satiating ability

Designing satiating food is not an easy task. Food reformulation is normally done by altering the proportion of basic ingredients or by adding new minor ingredients. In general, the texture varies concomitantly with these changes, altering the way the food is processed orally and the complete eating experience. This highlights the interest of discovering how variations in minor ingredients influence texture and how this affects the dynamics of the oral trajectory. Six cheese pie formulations were prepared: basic recipe (Base), no egg (− Egg), no corn starch (− Corn starch) no sugar (− Sugar), added diary cream (+ Cream) and extra skimmed milk powder (+ Milk powder). Temporal dominance of sensations was used to show that the appearance and disappearance of each texture sensation dominance experienced in the mouth during the eating process differed among the six pies, as did their relation to the consumers' expectation of satiating capacity scores and to the changes in composition. Two extreme behaviors were found: suppression of egg/addition of extra milk powder made the pies initially drier and harder, while suppression of corn starch/addition of cream gave the samples a soft, moist early sensation. The former elicited higher expectations of satiating capacity. In addition, overall liking, liking evolving with time (dynamic liking) and the level of several key texture attributes' divergence from those of an “ideal” cheese pie were evaluated on bipolar just-about-right scales and through penalty analysis to gain insights into potential directions for reformulating acceptable pies.     

Liking and the orosensory perception of food in a stress vs. rest condition in overweight and normal weight participants

Stress and increased body weight may lead to decreased sensory or hedonic perception. Rewarding value of food consists of liking and wanting; this study emphasizes characterization of orosensory perception and liking during stress. The effect of stress on orosensory attributes of food and liking was tested in overweight and normal weight participants. Thirty-nine participants (26f/13m, age 30 ± 11 y), 24 normal weight (BMI 22 ± 2 kg/m², waist/hip-ratio 0.78 ± 0.02) and 15 visceral-overweight (BMI 29 ± 2 kg/m², waist/hip-ratio 0.87 ± 0.02) tasted 67 food items randomly in a rest and stress condition, subsequently rating orosensory attributes (i.e., sweetness, bitterness, saltiness, sourness, umami, creaminess, crispiness) and liking using visual analog scales. Stress was induced using an unsolvable math task in a noisy context. In overweight participants, orosensory perception was less pronounced, especially with respect to sweetness. Liking was related to orosensory perception, the relationships were the same in both conditions. Liking was scored lower by overweight vs. normal weight participants. Stress vs. rest reduced orosensory perception in normal weight participants. Stress vs. rest reduced liking equally for normal weight and overweight participants. In conclusion, our results show that orosensory perception and liking of food are reduced in overweight compared to normal weight participants; the latter is especially emphasized during stress.     

Sensory profile,acceptability, and their relationship for diabetic/reduced calorie chocolates

The purpose of this study was to determine the sensory properties and acceptability of lab developed prototypes of conventional, diabetic (with no sugar), and diabetic/reduced calorie milk chocolates (no sugar and 25% calorie reduction) with high-intensity sweeteners, sucralose and stevioside, and partial fat replacement with whey protein concentrate (WPC). PLS was performed in order to relate sensory properties and consumer acceptability and to determine drivers of liking and disliking. There was no difference between conventional, diabetic and diabetic/reduced calorie milk chocolates for brightness, cocoa aroma, cocoa butter aroma, and cocoa flavor (p > 0.05). Acceptability was higher for sucrose substitution by sucralose than by stevioside and partial fat replacement reduced acceptability of flavor even more (p ? 0.05). Crucial attributes which determine consumer acceptability in samples are sweet aroma, melting rate, and sweetness, whereas bitterness, bitter aftertaste, adherence, and sandiness were drivers of disliking.     

Cultural influences in the origins of food likings and dislikes

This research investigates cultural influences on affective and cognitive bases or origins of food likes and dislikes in terms of cross-cultural differences (French from France, N = 118 vs. Chinese from PR China, N = 100) and acculturation (Chinese from PR China vs. Chinese accultured in Canada, N = 111). Content analyses on the reasons for liking and disliking food items support the expected cross-cultural differences between the French and the Chinese: the French display a dominant affective basis, whereas the Chinese attitude to food reflects more balance between affect and cognition. Comparisons between the Chinese acculturated into a Western culture and the Chinese from PR China revealed little change to the balance between bases for liking, and a shift toward a higher pre-dominance of the affective basis for dislikes. Theoretical and practical implications of the results are discussed.     

The influence of preparation method on children’s liking for vegetables

This study aimed to investigate how different preparation methods influence children’s liking for vegetables. Participants were children from three age groups (4–6 years N = 46; 7–8 years N = 25; 11–12 years N = 23) and young adults (18–25 years N = 22). The participants tasted and ranked six preparation methods for carrots and French beans: mashed, steamed, boiled, stir-fried, grilled and deep-fried. In addition, the different vegetable preparations were rated on 15 attributes. All participants preferred boiled and steamed vegetables over the other preparations (p < 0.05). Boiled and stir-fried were the most familiar preparation methods for both vegetables. Vegetable liking was positively related to a uniform surface and the typical vegetable taste, and moderately related to crunchiness, whereas brown colouring and a granular texture were negatively related to vegetable liking. On the basis of these results, we conclude that children’s vegetable liking is influenced by a complex mixture of a uniform appearance, easily controllable textures and a typical, familiar vegetable taste.     

Changes in liking for a no added salt soup as a function of exposure

Multiple exposures have been shown to increase preference for novel foods or flavours. This “mere exposure” effect is also well known anecdotally for changes in preference for tastants within foods, for example reducing sugar in tea or coffee. However, to date, this phenomenon has received little scientific attention. The present study addressed this issue in relation to changes in preference for salt within soup. Following an initial assessment of liking, familiarity and saltiness of six soups varying in salt content (0–337 mg NaCl/ml), 37 participants, previously assessed for their preferred salt level in soup, were allocated to either an exposure group that received 20 ml soup samples with no added salt, to a group that received a 280 ml bowl of this soup, or to a control group that received 20 ml soup samples containing salt at 280 mg/100 g (within normal, commercial range). Soups were presented on eight occasions, at approximately daily intervals. The two groups receiving the no added salt soup showed increases in liking starting at the third exposure, and also evident in a repeat assessment following the exposures. Increases in familiarity of the no added salt soup were also evident during exposure. Rated saltiness of all soups increased as a function of exposure, so a change in saltiness perception could not account for changes in liking for just the no added salt soups. These data suggest that simple exposure to the taste of the no added salt soup was sufficient to increase liking to a level equivalent to the initially more preferred salt level.     

Rejection thresholds (RjT) of sweet likers and dislikers

Sweetness is generally a desirable taste, however consumers can be grouped into sweet likers and dislikers according to optimally preferred sucrose concentrations. Understanding the levels of sweetness in products that are acceptable and unacceptable to both consumer groups is important to product development and for influencing dietary habits. The concentrations at which sucrose decreases liking (the rejection threshold; RjT) in liquid and semi-solid matrices were investigated in this study. Thirty six consumers rated their liking of 5 sucrose aqueous solutions; this identified 36% sweet likers (SL) whose liking ratings increased with increasing sucrose and 64% sweet dislikers (SD) whose liking ratings decreased above 6% (w/v) sucrose. We hypothesized that SL and SD would have different RjT for sucrose in products. This was tested by preparing 8 levels of sucrose in orange juice and orange jelly and presenting each against the lowest level in forced choice preference tests. In orange juice, as sucrose increased from 33 g/L to 75 g/L the proportion of people preferring the sweeter sample increased in both groups. However, at higher sucrose levels, the proportion of consumers preferring the sweet sample decreased. For SD, a RjT was reached at 380 g/L, whereas a significant RjT for SL was not reached. RjT in jelly were not reached as the sweetness in orange jelly was significantly lower than for orange juice (p < 0.001). Despite statistically significant differences in rated sweetness between SL and SD (p = 0.019), the extent of difference between the two groups was minor. The results implied that sweet liker status was not substantially related to differences in sweetness perception. Self-reported dietary intake of carbohydrate, sugars and sucrose were not significantly affected by sweet liker status. However the failure to find an effect may be due to the small sample size and future studies within a larger, more representative population sample are justifiable from the results of this study.     

Encapsulation of Lactobacillus rhamnosus in double emulsions formulated with sweet whey as emulsifier and survival in simulated gastrointestinal conditions

Lactobacillus rhamnosus cultured in sweet whey and harvested in the late log phase was entrapped in the inner aqueous phase of a double water-in-oil-in-water emulsion using concentrated sweet whey as emulsifier. The primary and double emulsion droplets showed practically no changes in their morphology and droplet size with aging time. The viability of the entrapped L. rhamnosus in the double emulsion was compared to that of non-entrapped control cells exposed to low pH and bile salt conditions. The viability of the control cells (initial number = 6.57 ± 0.3 log cfu ml^?1) decreased significantly under low pH and bile salt conditions, and their survival was 71% and 89%, respectively. The survival of the entrapped cells (initial number = 6.74 ± 0.2 log cfu ml^?1) increased significantly under low pH and bile salt conditions, and their survival was 108% and 128%, respectively. It is concluded that the double emulsion protected L. rhamnosus against simulated gastrointestinal tract conditions.     

Initial liking influences the development of acceptance learning across repeated exposure to fruit juices in 9–11 year-old children

In several studies, it has been found that repeated exposure to a novel food increases children’s acceptance of the exposure food. The present study, investigated how repeated exposure influences the acceptance of two Nordic berry juices, and whether the development depends on initial liking of the product, in 9–11 year-old children. The study had 317 participants. Two groups of children were exposed to either sea-buckthorn (n = 92) or aronia (n = 105) juice eight times, and performed two follow-up sessions 3 and 6 months after the 8th exposure. A third group (n = 120) served as controls. During pre and post-test sessions all participating children evaluated acceptance of both juices.Intake of sea-buckthorn juice increased significantly over the eight exposures (55.1 ± 7.3 till 108.8 ± 12.3) and remained high after 6 months (131.1 ± 13.2). Intake of aronia juice was only increased at follow-up sessions. Liking did not develop significantly for any of the juices across exposures. When children were grouped by their initial liking increased intake across exposures was observed regardless of initial liking of sea-buckthorn. Liking developed similarly for both juices. A significant increase was found for the ‘initial dislikers’ only. This study demonstrates how exposure effects are influenced by initial liking; it appears that changes in familiarity explain the changes seen for sea-buckthorn among ‘dislikers’. ‘Initial dislikers’ had the most benefit from repeated exposures, but did not reach ‘initial likers’ across eight exposures; more exposures in the group of ‘initial dislikers’ had possibly led to even higher liking and intake. The increased intake observed for ‘neutral likers’ and ‘initial likers’ of sea-buckthorn was not explained by increased familiarity or increased liking.     

Genetic and environmental influences on liking and reported intakes of vegetables in Irish children

Variation in the bitterness of 6-n-propylthiouracil (PROP) is partially explained by polymorphisms in the TAS2R38 gene. Based on their perception of bitterness from PROP, people may be classified into non-, medium and supertasters. PROP perception has previously been linked to liking for cruciferous vegetables in children in some studies, but only one study to date has examined TAS2R38 genotype and its relationship with vegetable intake in children. Children’s vegetable consumption generally does not meet the recommended guidelines, thus the present study aimed to examine the influence of oral sensory measures, genetic variation and social factors on vegetable liking and intake. Vegetable liking in 7–13 year old Irish children (n = 525) was measured on a 5-point liking scale, and dietary intakes were assessed via a 3-day diet history. Vegetable intakes were calculated and standardised per kg body weight. A subset of children (n = 485) were genotyped for SNPs in TAS2R38, (A49P, V262A, I296V), and fungiform papilla (FP) were counted. The bitterness of PROP and sweetness of sucrose were rated on a generalised labelled magnitude scale (gLMS). PROP and sucrose intensity were significantly correlated (R² = 0.33, p = 0.001), although neither sucrose intensity nor FP density differed across the TAS2R38 genotype groups. Supertasters were less likely than nontasters to have tried/tasted cruciferous vegetables p < 0.04). A small, positive correlation was seen in FP density and vegetable intake, but only in the AVI homozygous children, (R² = 0.17, p = 0.035). 174 Nutrient acceptable children reported an intake of one or more of the vegetables of interest in the 3-day period. Liking of cruciferous vegetables and reported intake were significantly correlated. In multiple regression analyses in this subsection of the cohort, socioeconomic status (SES) and gender were more important than PROP bitterness or TAS2R38 genotype in predicting intakes (approximately 15% of liking and 67% of intake was explained by these models). Overall, neither PROP taster status nor TAS2R38 genotype alone had significant impact on bitter vegetable liking or intake. Further research into FP density and vegetable liking and intake may be warranted.     

Providing a food choice option increases children’s liking of fish as part of a meal

Fish consumption in Norway is lower than currently recommended by health authorities. Parents report various barriers to fish consumption, including children’s dislike of and avoidance to choose fish and resulting family conflicts. Often children are served one main meal option. However, giving children a choice between two types of meals with fish may increase liking of fish.The aim of this study was to experimentally investigate the effect of choice possibility on liking evaluation of fish by children.Two groups of children (n = 131) were compared: group 1 (n = 76) without a choice possibility for a fish dish (cod or salmon) and group 2 (n = 55), with a choice possibility between cod and salmon dishes. The experiment took place in a canteen where children evaluated liking of the fish in the dish. Children also reported preferences, consumption frequency and psychosocial development characteristics.Giving children a choice between the cod and salmon dishes led to a more positive liking evaluation of the fish in the dish. Children with developed choice ability reported lower liking evaluations for fish in a dish they were given without a choice possibility. General liking of fish increased liking evaluations whether the children were given a choice possibility or not.These results may be explained by a positive bias the children have towards choices they make, especially when they believe they are able to be more autonomous. These results indicate that children may learn to like fish more if they are included in the process of deciding what to have for dinner.     

Preference for salt in a food may be alterable without a low sodium diet

In response to current efforts to reduce population-wide dietary salt intake, the objective of this study was to determine whether liking for reduced sodium and low sodium tomato juice could increase following repeated exposure over an extended period. Eighty-three adult subjects participated in a three-part study: an initial taste test, a 16-week longitudinal study, and a final taste test. Subjects gave liking ratings of four tomato juice samples ranging in sodium from 640 mg (a concentration comparable to a commercially available product) to 136 mg per 237 ml serving (a low sodium concentration) at both taste tests. For the longitudinal study, subjects were divided into two balanced groups based on PROP sensitivity, hedonic sensitivity to salt, and motivation to reduce dietary salt intake; the abrupt group received tomato juice reduced in sodium to reach a low sodium target at week four, and the gradual group received juice reduced in sodium via difference thresholds to reach the same target at week 14. Though liking for the juice with the highest salt content was unchanged between taste tests, liking for all reduced salt juices increased at the final taste test relative to the initial taste test among subjects in both salt reduction groups. In addition, subjects in both groups experienced a downward shift in preference for salt in tomato juice, indicating that repeated exposure may be sufficient to alter preference for salt in a food in the absence of a low sodium diet. That salt preference may be altered by exposure alone within the context of a high salt diet is promising for both the food industry and individual consumers.     

Texture preferences of 12-month-old infants and the role of early experiences

The present study examined infants’ preferences for different food textures and aimed to identify factors that play an important role in shaping these preferences. In a home setting, 70 twelve-month-old infants were exposed to cooked carrots prepared in two different textures; pureed and chopped. Infants’ mean intakes in grams for the pureed and the chopped carrots were 70.9 ± 49.1 g and 24.6 ± 28 g respectively. Infants consumed significantly more pureed carrots (t(69) = 8.50, p < 0.001) and mothers’ rating of the infants’ enjoyment for this texture was significantly higher (t(69) = 3.65, p < 0.01) than for chopped carrots. However a great variability in the consumption of chopped carrots was found within the infants. Spearman’s correlation and PLSR analysis showed that familiarity with different textures, especially chopped foods, is the strongest predictor of intake and liking of chopped carrots. Furthermore, infants with higher dietary variety, more teeth and a greater willingness to try new foods were more likely to consume more of the chopped carrots. Food pickiness and fussiness had a negative influence on the intake of, and liking for, chopped carrots. The present research is a first step to explain the variation in infants’ consumption and liking of different textures. It highlights the importance of not only varying the child’s experiences with different flavours but also with different textures to foster the infants’ transition to an adult diet.     

Acquisition of liking for spinach products

This research investigated whether consumers acquire a liking for spinach through tasting it many times (repeated exposure) or in association with something which is better-liked (associative learning). The research focused on women who ate spinach infrequently or did not eat spinach at all, did not have a strong liking or disliking for spinach and were prepared to try the vegetable again. The experiment consisted of three phases; a pre-test, followed by a learning phase and finally a post-test. Two hundred and twenty-three consumers participated in a pre- and post-test evaluation of plain spinach at a central location. They were divided into five different groups for the learning phase, with approximately 40 consumers in each. A ‘control’ group of consumers was not given a product. The other consumers were given the same product (either peas, spinach type 1, spinach type 2 or a cream spinach recipe, containing cheese and spices) once a week for five weeks to prepare at home according to specified instructions and consume as an accompaniment to a hot meal. Acquisition of liking was found; repeated consumption of plain spinach did result in an increased liking for plain spinach overall (p = 0.02) and specifically for spinach dislikers (p < 0.05). At an overall level, flavour–flavour pairing effects were not demonstrated. However, consumers who initially disliked spinach showed an increased liking (p < 0.05) for spinach after having repeatedly eaten it in the learning phase as part of a recipe with cream, cheese and spices.