Comparative performance of the nine-point hedonic, hybrid and self-adjusting scales in the generation of internal preference maps

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)This study evaluated the performance of the nine-point hedonic, hybrid and self-adjusting scales in the segmentation of samples and consumers using MDPREF methodology. Overall acceptability of eight Cabernet Sauvignon red wines was evaluated by 112 consumers using the three scales mentioned above. Both the scale's and the sample's presentation order were balanced among the consumers. The data were analyzed by ANOVA, REGWQ test, MDPREF and permutation tests. Scales' performance was judged using the following criteria: number of significant dimensions (p = 5%) in the MDPREF, number of significantly fitted consumers (p = 5%) and segmentation of the products and consumers. The MDPREF generated by the hybrid scale data produced the greatest number of significant dimensions (p = 5%), yielding 79.5% of significantly fitted consumers (p = 5%), while the MDPREFs of the self-adjusting and the nine-point scales fitted 54.5% and 51.8% of the consumers, respectively. Overall, the results indicated superiority of the hybrid scale over the traditional hedonic and self-adjusting scales. (C) 2008 Elsevier Ltd. All rights reserved.201112Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Effect of nutrition and health claims on the acceptability of soyamilk beverages

The effect of expectation on the acceptability of four types of yoghurt-like fermented soyamilk was studied among fifty-three subjects. Overall liking was rated under three conditions: (1) blind test (B); (2) expectations created by nutritional and health claims about the products (E) and (3) subjects re-tasted the beverages, having the nutrition and health claims available (R). Student's t-tests performed on data indicated no significant differences (P > 0.05) between acceptance levels under the blind (B) and real (R) conditions, although expectation ratings (E) were significantly higher (P < 0.05) than (B) and (R). However, linear regression of (R - C) x (E - C) ratings for each sample revealed a major assimilation effect of expectation, especially under negative disconfirmation (when the product was evaluated as worse than expected). Contrast effect was also observed, but to a lesser extent. In conclusion, information influenced positively on the acceptance, although such influence was limited by the subjects' sensory experience.421505

Performance of three affective methods and diagnosis of the ANOVA model

Consumer data arising from traditional scales frequently do not comply with ANOVA assumptions of normality, independence and homoscedasticity. Differential expansiveness of scoring between assessors is also a limitation in the use of scales. The self-adjusting scale was designed to minimize some of these problems but its performance with consumers has not been reported. This study compared the performance of the 9-point hedonic scale, the self-adjusting scale and the ranking test with respect to: differential expansiveness between assessors, discriminating power and compliance of data with ANOVA assumptions. Candies were evaluated by 288 consumers. Data normality was checked by normal probability plots, Kolmogorov-Smirnov test and coefficients of skewness and kurtosis. Homoscedasticity assumptions were evaluated by the Levene test and scatterplots. The self-adjusting scale was effective to deal with differential assessor expansiveness, produced homogeneous variances but its data showed gross deviations from normality. Hedonic scale data showed slight deviation from normality and lack of homoscedasticity. Rank and self-adjusting scale showed the highest and the lowest discriminating power, respectively. (C) 2000 Elsevier Science Ltd. All rights reserved.11536337

Fermentation of soymilk by commercial lactic cultures: Development of a product with market potential

Soymilk suppleniented with 2% sucrose was inoculated witli a mixture of Streptococcus thermophilus, Bifidobacterium lactis and Lactobacillus acidophilus. The fermentation was monitored by pH as a function of time. Tins sample was used as a basis for the fomulation of beverages flavoured with pineapple, strawberry, coconut, kiwi, guava and hazelnut. The beverages were submitted to a sensory acceptance test with consumers using the nine-point structured hedonic scale. ANOVA and Preference Mapping were used to analyse data and results showed higher significant (P<0.05) acceptance for pineapple and guava flavours. The strawberry, kiwi and coconut flavours obtained acceptance close to 6.0 (liked slightly), while the hazelnut flavour was rejected (acceptance less than 5.0). This study demonstrated that it is possible to formulate highly acceptable soymilk beverages by way of lactic fermentation and addition of flavourings.33210110

The efficiency of TBHQ, beta-carotene, citric acid, and tinuvin 234 (R) on the sensory stability of soybean oil packaged in PET bottles

The use of plastic packaging for oils permits exposure to light, increasing oxidation. The goal of this work was to maximize sensory stability of soybean oil packaged in PET bottles. A central composite design was used to combine different levels of TBHQ, beta-carotene, and citric acid, added to oil, and Tinuvin 234(R), added to bottles. After 6 mo of storage, the oxidation degree was assessed by sensory and peroxide tests. TBHQ and Tinuvin 234 were the most effective antioxident, and the minimum concentrations required to keep a reasonable stability during storage were: 120 ppm of TBHQ; 7 ppm of beta-carotene; 15 ppm of citric acid and 0.1% of Tinuvin 234.68130230

Development of extruded snacks using jatoba (Hymenaea stigonocarpa Mart) flour and cassava starch blends

The use of the jatoba trees (Hymenaea stigonocarpa Mart) by the timber industry poses an ecological problem in Brazil. The objective of this research was to investigate the use of jatoba flour for the production of snacks by the thermoplastic extrusion of a composite flour consisting of jatoba and cassava starch. Chemical analysis showed that the jatoba fruit provides high-fibre flour (486 g kg(-1)) with 66 g kg(-1) protein, and 398 and 88 g kg(-1) of insoluble and soluble fibre, respectively. Such flour is of potential use for the production of high-fibre snacks, allowing for the economical exploitation of the jatoba while preserving the tree. Composite flours with jatoba flour and cassava starch mixtures (150:850, 300:700, 450:550), conditioned to moisture levels of 170, 200 and 230 g kg(-1) were processed in a Brabender single-screw extruder. The extrusion conditions were 150 rpm screw speed, 4 mm die diameter and 125, 150 and 175 degrees C of barrel temperatures. The snacks produced were evaluated as to their sensory characteristics and response surface methodology was used to optimise the extrusion process. Response surface and contour diagrams revealed that all mixtures conditioned to 170 g kg(-1) moisture and extruded at 150 degrees C produced snacks of acceptable quality, higher levels of jatoba flour leading to significant quality losses with respect to sensory characteristics. (C) 1998 Society of Chemical Industry.781596

Selective attention to affective value alters how the brain processes olfactory stimuli

How does selective attention to affect influence sensory processing? In a functional magnetic resonance imaging investigation, when subjects were instructed to remember and rate the pleasantness of a jasmin odor, activations were greater in the medial orbitofrontal and pregenual cingulate cortex than when subjects were instructed to remember and rate the intensity of the odor. When the subjects were instructed to remember and rate the intensity, activations were greater in the inferior frontal gyrus. These top-down effects occurred not only during odor delivery but started in a preparation period after the instruction before odor delivery, and continued after termination of the odor in a short-term memory period. Thus, depending on the context in which odors are presented and whether affect is relevant, the brain prepares itself, responds to, and remembers an odor differently. These findings show that when attention is paid to affective value, the brain systems engaged to prepare for, represent, and remember a sensory stimulus are different from those engaged when attention is directed to the physical properties of a stimulus such as its intensity. This differential biasing of brain regions engaged in processing a sensory stimulus depending on whether the cognitive demand is for affect-related versus more sensory-related processing may be an important aspect of cognition and attention. This has many implications for understanding the effects not only of olfactory but also of other sensory stimuli.O TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE NOVEMBRO DE 2014.201018151826Gottlieb-Daimler- and Karl Benz-Foundatio

Aroma compounds derived from the thermal degradation of carotenoids in a cashew apple juice model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The thermal degradation of carotenoids in cashew apple (Anacardium occidentale L) juice leads to changes in the beverage colour, and possibly in the aroma and flavour, although the latter hypothesis has not yet been properly investigated. Thus the objective of this study was to investigate the formation of odour active volatiles derived from the thermal degradation of carotenoids in a cashew apple juice model. A carotenoid extract in an acidic aqueous medium was submitted to 60 and 90 degrees C for 1 and 2 h. The non-volatile compounds were identified by high performance liquid chromatography coupled with a photodiode array and mass spectrometry detectors (HPLC-PDA). The volatiles were isolated by headspace-solid phase micro-extraction, separated by gas chromatography, identified by mass spectrometry (SPME-GC-MS) and their odour significance assessed by GC-Olfactometry. Thirty-three odour active volatiles were identified in the heated system, amongst which 1,2,3,5-tetramethylbenzene, naphthalene and p-xylene. The results indicated that the volatiles formed from the thermal degradation of the carotenoids influence the aroma and flavour of thermally processed cashew apple products. (C) 2013 Elsevier Ltd. All rights reserved.56108114Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Aroma volatiles recovered in the water phase of cashew apple (Anacardium occidentale L.) juice during concentration

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)BACKGROUND: There is a considerable loss of volatile compounds during the thermal concentration of cashew apple juice, damaging product quality, and as yet there is little research on the subject. Thus the purpose of this research was to identify the aroma volatiles evaporated off from cashew apple juice and recovered in the water phase during concentration of this beverage in an industrial plant. Water phase volatiles were extracted using dichloromethane, concentrated under a nitrogen flow, separated by gas chromatography (GC) and identified by GC-mass spectrometry. In order to determine the contribution of each volatile to the cashew aroma, five trained judges evaluated the GC effluents using the Osme GC-olfactometry technique. RESULTS: 71 volatiles were identified; of these, 47 were odour active. Alcohols were preferentially recovered in the cashew water phase, notably heptanol, trans-3-hexen-1-ol and 3-methyl-1-butanol, representing 42% of the total chromatogram area and imparting green grass and fruity aroma notes to the water phase. Esters represented 21% of the total chromatogram area, especially ethyl 2-hydroxyhexanoate, ethyl trans-2-butenoate and ethyl 2-methylbutanoate, and were responsible for the fruity/cashew-like aroma of the water phase. On the other hand, 3-methylbutanoic and 2-methylbutanoic acids were the volatiles that presented the greatest odour impact in the GC effluents of the water phase. CONCLUSION: Overall, the results of the present study strongly indicated that further concentration of the esters recovered in the water phase, either by partial distillation or by alternative technologies such as pervaporation, could generate a higher-quality natural cashew apple essence. (C) 2011 Society of Chemical Industry911018011809Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Bank of Interamerican Regional Development (BIRD)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

How pleasant and unpleasant stimuli combine in different brain regions: Odor mixtures

Many affective stimuli are hedonically complex mixtures containing both pleasant and unpleasant components. To investigate whether the brain represents the overall affective value of such complex stimuli, or the affective value of the different components simultaneously, we used functional magnetic resonance imaging to measure brain activations to a pleasant odor (jasmine), an unpleasant odor (indole), and a mixture of the two that was pleasant. In brain regions that represented the pleasantness of the odors such as the medial orbitofrontal cortex (as shown by activations that correlated with the pleasantness ratings), the mixture produced activations of similar magnitude to the pleasant jasmine, but very different from the unpleasant indole. These regions thus emphasize the pleasant aspects of the mixture. In contrast, in regions representing the unpleasantness of odors such as the dorsal anterior cingulate and midorbitofrontal cortex the mixture produced activations that were relatively further from the pleasant component jasmine and closer to the indole. These regions thus emphasize the unpleasant aspects of the mixture. Thus mixtures that are found pleasant can have components that are separately pleasant and unpleasant, and the brain can separately and simultaneously represent the positive and negative hedonic value of a complex affective stimulus that contains both pleasant and unpleasant olfactory components. This type of representation may be important for affective decision making in the brain in that separate representations of different affective components of the same sensory stimulus may provide the inputs for making a decision about whether to choose the stimulus or not.O TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE FEVEREIRO DE 2015.2749135321354