Comparing consumer liking of beef from three feeding systems using a combination of traditional and temporal liking sensory methods.

Research on the effects of animal diet on consumer liking of beef has yielded conflicting results. Currently it is unknown whether dynamic changes occur in liking during consumption of beef. This study applied a combination of traditional and temporal (free and structured) liking methods to determine consumer liking of beef derived from animals that were fed grain (GF), grass silage plus grain (SG) or grazed grass (GG) during finishing. Three separate panels of beef eating consumers (n = 51; n = 52; n = 50) were recruited from Teagasc Food Research Centre, Dublin, Ireland to assess striploin steaks from animals fed either GF, SG, or GG. Using the free temporal liking (TL) method, results revealed that beef from GF animals was liked significantly less (p ≤ 0.05) in terms of overall liking, tenderness and juiciness, when compared to steaks from the SG and GG animals. These effects were not observed using the structured TL or traditional liking methods. Further analysis showed the evolution of scores over time was significant (p ≤ 0.05) for all attributes using the free TL method. Overall, the free TL method yielded more discriminative data and was perceived as easier to perform by consumers compared to the structured TL method. These results show that the free TL method may provide an opportunity to elicit more in-depth information regarding consumer sensory response to meat.

Sensory evaluation of dark origin and non-origin chocolates applying Temporal Dominance of Sensations (TDS).

Dark chocolates are rich sources of polyphenols, widely acknowledged for eliciting several beneficial health effects. However, these compounds are key inducers of bitter taste and astringency, potentially limiting consumers' acceptance of chocolates with higher cocoa contents. In order to gain better insight in consumers' choices, the present study investigated the temporal profile of bitterness and astringency as well as sweet taste as covering agent, during the testing period in 5 dark origin (OR) (66.8-80.1% cocoa) and 6 non-origin (N-OR) (54.5-80.0% cocoa) chocolates with different cocoa contents, applying Temporal Dominance of Sensations (TDS). The temporal profile of the evaluated OR chocolates was characterized by the dominance of bitterness independent of cocoa contents (%cc), reaching maximum dominance rates (DR%) between 60.0 and 80.0% over approximately 75.0% of the testing period, i.e. prior to swallowing. After swallowing, astringency dominated, mostly not significantly. DR (%) of sweetness reached the level of significance only in one sample (OR 67.4%cc). N-OR chocolates with 54.5-60.0%cc were characterized by significant dominances of sweet taste along the entire evaluation period, reaching maximum DR% between 90 and 95%. The increase of cocoa contents was combined with higher DR% of bitter taste. Astringency dominated in N-OR samples at the end of the evaluation period presumably after swallowing. Finally, in N-OR chocolates, cc% highly affected the dominance of the evaluated attributes. This impact was found to be rather minor or absent in OR chocolates. Thus, the TDS-parameters showed variations in attribute's dominance in OR and N-OR chocolates indicating a strong influence of cocoa bean variety and local conditions (environmental and farming conditions as well as post-harvest treatment practices) in addition to cocoa contents.

Measuring temporal liking simultaneously to Temporal Dominance of Sensations in several intakes. An application to Gouda cheeses in 6 Europeans countries.

The idea of having untrained consumers performing Temporal Dominance of Sensations (TDS) and dynamic liking in the same session was recently introduced (Thomas, van der Stelt, Prokop, Lawlor, & Schlich, 2016). In the present study, a variation of the data acquisition protocol was done, aiming to record TDS and liking simultaneously on the same screen in a single session during multiple product intakes. This method, called Simultaneous Temporal Drivers of Liking (S-TDL), was used to describe samples of Gouda cheese in an international experiment. To test this idea, consumers from six European countries (n=667) assessed 4 Gouda cheeses with different ages and fat contents during one sensory evaluation session. Ten sensory attributes and a 9-point hedonic scale were presented simultaneously on the computer screen. While performing TDS, consumers could reassess their liking score as often as they wanted. This new type of sensory data was coded by individual average liking scores while a given attribute was perceived as dominant (Liking While Dominant; LWD). Although significant differences in preference were observed among countries, there were global preferences for a longer dominance of melting, fatty and tender textures. The cheese flavour attribute was the best positive TDL, whereas bitter was a strong negative TDL. A cluster analysis of the 667 consumers identified three significant liking clusters, each with different most and least preferred samples. For the TDL computation by cluster, significant specific TDL were observed. These results showed the importance of overall liking segmentation before TDL analysis to determine which attributes should have a longer dominance duration in order to please specific consumer targets.

Impact of information and in-home sensory exposure on liking and willingness to pay: The beginning of Fairtrade labeled coffee in France.

This study was conducted to assess how the Fairtrade label interacts with the perception of intrinsic product characteristics on liking and purchase decisions and to estimate the evolution of this interaction after exposure to coffees and/or exposure to ethical information. In the first session, 119 consumers gave liking scores for 2 regular and 2 Fairtrade coffees under a blind tasting condition. Then, they were asked to indicate the maximum price they would pay for each product in 2 auctions taking place under different information conditions. In the first auction, participants saw the packaging but did not taste the coffee; in the second auction, they could both taste the coffee and see the packaging. After the first session, the consumers were randomly split into 4 groups, and these groups were exposed for one month to different conditions before returning to the lab for exactly the same measurements as in the first session. The first of the 4 groups was not exposed to sensory characteristics or ethical information. Each consumer of the second group was only exposed to sensory characteristics of the coffees (one packet of his/her least liked regular and ethical coffees delivered in blind packaging for home consumption). The third group was exposed to sensory characteristics and ethical information (the same as the second group but using the original coffee packaging showing fair trade information). The final group was only exposed to ethical information. Results showed that the hedonic scores of the least liked ethical and regular products increased from sessions 1 to 2, but not significantly more when consumers were exposed to these products between the sessions. However, while consumers offered lower prices for ethical products at the first session, those who were exposed to ethical information increased their willingness to pay for ethical products. This effect became statistically significant when consumers could taste the products before making their bid. The effect of exposure to ethical information was also transferred to the willingness to pay for the ethical product to which the consumers were not exposed. This study highlights the interest of a design, which makes it possible to assess the impact over time of sensory and external information on the willingness to pay.

Associations between weight status and liking scores for sweet, salt and fat according to the gender in adults (The Nutrinet-Santé study).

BACKGROUND/OBJECTIVES: As taste preferences may be associated with obesity, the present study investigated whether obese subjects presented heightened liking for the sensations of sweet, salt and fat. SUBJECTS/METHODS: Liking scores were determined by a questionnaire including 83 items on liking for sweet or fatty foods, and the preferred extent of seasoning with salt, sweet or fat. Data from 46909 adults included in the French web-based observational cohort of the Nutrinet-Santé study were collected and weighted according to the national population census. Relationships between liking scores and body mass index (BMI) as categorical or linear explanatory variable were assessed separately by gender using covariance and linear regression analyses, adjusted for age, education level, living area, smoking and alcohol. RESULTS: Overall liking scores for salt and fat were linearly positively linked to BMI in men and women (P≤0.001) and were higher in obese than in normal-weight individuals. The score difference between BMI categories was greater in women for fat liking only. For sweet liking, results differed between gender and compounding factors. Liking for added sugar and sweet foods was positively linked to BMI in women unlike in men; liking for natural sweetness was negatively linked to BMI in both genders. CONCLUSIONS: This study demonstrates that the relationship between liking and BMI differs according to the gender in its magnitude for fat and in its nature for sweet, unlike that for salt. Liking for sweet and fat may be linked to overconsumption of the corresponding foods, especially in women. This warrants further investigation.

Effect of sensory education on willingness to taste novel food in children.

As part of 'EduSens', a project aiming to measure the effect of a sensory education program developed in France on the food behaviour of school children, the present paper shows the results regarding neophobia. One hundred and eighty children (8-10 years old) were involved in the study. Half of them (experimental group) were educated during school-time with the 12 sessions of taste lessons "Les classes du goût" by J. Puisais. The others served as a control group. Food neophobia was evaluated before and after the education period of the experimental group and once again 10 months later. An adapted food neophobia scale was used (AFNS) and the willingness to taste novel food (WTNF) was evaluated by the presentation of eight unknown foods. To improve involvement in the expressed willingness to taste new foods, the children were told that they would have to eat one of the not rejected unknown foods afterwards. Results revealed that, at the end of the education period, in the educated group, declarative food neophobia decreased significantly and participants' willingness to taste novel food seemed to increase compared to the control group. Nevertheless, these effects had disappeared 10 months later. Thus, we have shown that sensory education can influence childrens' food neophobia, but does so only temporarily. This is especially true for the WTNF test, which measures the expression of neophobia in concrete situations, whereas neophobia measured as a psychological trait by the AFNS test hardly changes.

Is the desire to eat familiar and unfamiliar meat products influenced by the emotions expressed on eaters' faces?

The aim of the present study was to test if the social context represented by eaters' faces expressing emotions can modulate the desire to eat meat, especially for unfamiliar meat products. Forty-four young men and women were presented with two series of photographs. The first series (non-social context) was composed of eight meat pictures, four unfamiliar and four familiar. The second series (social context) consisted of the same pictures presented with eaters expressing three different emotions: disgust, pleasure or neutrality. For every picture, the participants were asked to estimate the intensity of their desire to eat the meat product viewed on the picture. Results showed that meat desire depended on interactions between product familiarity, social context and the participant's gender. In the non-social context, the men liked the familiar meat products more than the women, whereas their desire to eat unfamiliar meat products was similar. Compared to the non-social context, viewing another person eating with a neutral and a happy facial expression increased the desire to eat. Furthermore, the increase in the desire to eat meat associated with happy faces was greater for the unfamiliar than for the familiar meat products in men, and greater for the familiar than for the unfamiliar meats in women. In the presence of disgusted faces, the desire to eat meat remained constant for unfamiliar products in all participants whereas it only decreased for familiar products in men.

Emotions generated by meat and other food products in women.

Eating behaviour depends partly on food preference, which is itself determined by different types of emotions. Among the emotions generated by food, disgust with red meat is common in women and can lead to reduced meat consumption. We tested the hypothesis that low meat intake is related to different negative emotions towards meat but does not affect the emotions expressed towards other food categories. Food intake of sixty women was followed throughout each day for 1 week and allowed us to assign women to two groups (low v. high meat-eating women). They were then invited to assess the intensity of twenty-six emotions described by words and induced by thirty food pictures. We determined the number of necessary dimensions to describe the space created by the twenty-six words. The results showed differences in emotions between the low and high meat-eating women. As expected, there were overall differences in the emotions generated by the thirty food pictures. Six clusters of emotions were necessary and sufficient to summarise the emotional space. These dimensions were described by 'disappointment', 'satisfaction', 'guilt', 'doubt', 'amused' and 'indifference'. As expected, the low meat-eating women felt more 'disappointment', 'indifference' and less 'satisfaction' towards meat than did the high meat-eating women. However, the low meat-eating women also stated other negative emotions such as 'doubt' towards some starchy foods. The only foods that they liked more than high meat-eating women were pears and French beans. In conclusion, low meat consumption was associated with specific negative emotions regarding meat and other foods.

Using sensory and instrumental data to interpret the effect of storage at elevated temperatures on aroma of Chardonnay wines.

The effect of elevated temperatures during storage on the aroma of commercial Chardonnay wines was monitored by sensory and instrumental methods. Aromas of wines stored at 40 degrees C for 0, 15, 30 and 45 days were profiled by descriptive analysis by a trained panel. Heated storage decreased intensity of fruity and floral notes, while increasing attributes such as honey, butter/vanilla, oak, and rubber. Volatiles recovered by solvent extraction from the same wines were separated by gas chromatography (GC) and identified by GC-mass spectrometry (MS). Principal component analysis of instrumental variables (PCAIV) was used to reduce the initial set of 67 quantified GC peaks. Six compounds, selected by PCAIV to yield the configuration closest to that of the principal component analysis of the sensory data, provided a highly significant fit with the sensory configuration, as shown by a permutation test. This solution was the statistically optimal one, but was not unique, as demonstrated by significant fits between the sensory and instrumental spaces upon use of other GC peaks, which were highly correlated with the original six variables.

Use of anti-M. leprae phenolic glycolipid-I antibody detection for early diagnosis and prognosis of leprosy.

Untreated patients suffering from tuberculoid, lepromatous and indeterminate leprosy, their domiciliary contacts, and healthy controls, all living in Guadeloupe, West Indies, were tested by an ELISA for detecting IgM antibodies to the terminal disaccharide of the phenolic glycolipid-I antigen of Mycobacterium leprae. On most subjects, a Mitsuda test was also performed. A large majority of the tuberculoid patients and healthy subjects were Mitsuda positive. The seropositivity rate reached 44% among tuberculoid patients, and 6% among healthy subjects, with low antibody levels. Lepromatous patients were all Mitsuda negative and seropositive, with antibody production varying from low levels, as seen in tuberculoid patients, to much higher levels. Indeterminate leprosy patients included 62% Mitsuda-positive subjects and 54% seropositive subjects with a large dispersion of antibody levels. Comparing the results of the Mitsuda test to those of the ELISA by factorial analysis allowed us to define several subgroups among this population: some (25%) showed a "lepromatous-like" immune status (Mitsuda negative, seropositive); others (54%) exhibited "tuberculoid-like" profiles (Mitsuda positive without antibodies or with low antibody levels). "Lepromatous-like" cases were significantly older than "tuberculoid-like" patients. A group of subjects (17%) was Mitsuda negative and seronegative, thus displaying a true "indeterminate" immune profile, which had not been seen in other forms of the disease and had been observed in only 2 out of 51 healthy controls. A large majority of contacts was Mitsuda positive, with 33% of them being seropositive, indicating that the prevalence of M. leprae infection greatly exceeds that of overt leprosy in this population.(ABSTRACT TRUNCATED AT 250 WORDS)