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1.
This study investigated the effect of hunger on consumers’ visual attention during a food choice task, and the role of time orientation (i.e., present and future orientation) in this interplay. A lab-based eye-tracking experiment including 102 participants was conducted, with hunger as the manipulated factor (hungry, satiated). Participants in the satiated condition were served a breakfast buffet before the experimental tasks, whereas participants in the hungry condition were served the buffet after completion of the tasks. Both groups were exposed to a set of planograms depicting supermarket shelves and were asked to choose an option they could consider buying, while their eye movements were recorded. Stimuli included non-food items as well as the key category of interest, Swedish crisp bread. After completion of the eye-tracking recordings, participants indicated their time orientation as well as their height and weight, which were used to calculate body mass index (BMI). The results revealed that hunger (vs. satiation) increased participants’ present orientation and visual attention towards bread, but decreased their future orientation, with participants’ present orientation mediating the effect of hunger on visual attention. Additional exploratory analyses revealed a positive correlation between participants’ BMI and their present orientation. Taken together, the results offer several fruitful avenues for future research, which may be used to promote public health. Moreover, the findings contribute to the literature by documenting that hungry individuals do not necessarily make more rapid decisions in drive-relevant domains; rather, they may actually devote a larger share of their attentional resources in the food domain, given their desire to acquire food.  相似文献   

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We report evidence concerning how the visual appearance of a drink (dark vs. light pale/amber beer) can influence the consumer’s tasting experience. Two experiments were designed to study the effect of visual appearance on people’s hedonic and sensory judgments of beer. Importantly, the beers were indistinguishable in terms of their flavor when tasted in the absence of visual cues.Participants rated the same beer (pale or dark, depending in which group they were assigned) under blind conditions as having more body than when tasted under sighted condition (regardless of whether it was pale or dark; see Experiment 1).When the participants evaluated the expectations and tasting experience of the two different beers under sighted conditions (pale vs. dark), after tasting, those who preferred pale beers, rated the darker beer as tasting sweeter than those who usually prefer other types of beers, such as dark ones (see Experiment 2). Prior tasting, when asked which beer they thought was the most expensive, the majority of the participants chose the darker beer. Furthermore, after tasting both beers, participants reported being willing to pay up to 6% more on average for the darker beer as compared to the pale one.  相似文献   

4.
The influence of reducing and oxidizing buckwheat sourdoughs on the rheological, protein, and bread properties of buckwheat and brown rice flour was investigated. Batters and breads prepared with chemically acidified doughs, fresh pre-doughs, and fresh pre-doughs containing glutathione (3 mM) were used as controls. No significant differences were observed after the addition of reducing and oxidizing sourdoughs in all trials. Proteolysis was observed after proofing time in buckwheat and brown rice batters, respectively. Acidified doughs increased the elasticity and the gelatinization temperature of buckwheat batters. No notable microstructure changes were detected in brown rice batters. The extension of fermentation time in sourdough caused a slight decrease in bread volumes in all trials. Sourdoughs increased the bread volume and decreased the crumb hardness of buckwheat breads. In trials with brown rice flour, the addition of sourdough did not show relevant volume differences as compared to the controls, except big voids in sourdough bread crumb. Linear correlations between hardness, volume, and cells’ density were observed. However, no clear correlations among rheological parameters and bread characteristics could be detected. These results indicated that the applied strains were responsible for the leavening capacity of the yeast during the proofing time and for crumb structure in trials with buckwheat and brown rice flour. Applied sourdoughs were able to change the molecular, and bread properties of buckwheat and brown rice bread.  相似文献   

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The overall impression of a glossy surface is an important parameter for consumer’s choice of wooden products. A new gloss parameter, called gloss impression, which calculates a reflexion structure image, was developed in order to complement the measurements made by industrial glossmeters, which are highly limited in describing the visual human perception, for example the commonly used gloss value. The objective of this study is to investigate to what extent the new measurement method of surface gloss is applicable to describe human gloss perception, in other words, to validate the new method. In order to analyse the concordance of the new methodology with human perception, 113 naïve observers had to rank the glossiness of eight series of black and white samples. The results were compared to both gloss impression and gloss value. The statistical evaluation by means of Pearson’s chi-squared tests revealed that the new method has an overall better correspondence to human perception than the gloss value. For black samples, it describes human perception significantly better than the gloss value and gives better results than those which would be achieved by guessing.  相似文献   

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Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60, 70, and 80 °C) and time (6, 12, and 24 h). Different physicochemical, histological and structural parameters were studied. Increasing cooking temperatures led to higher weight losses and lower moisture contents, whereas the effect of cooking time on these variables was limited. Samples cooked at 60 °C showed the highest lightness and redness, while increasing cooking temperature and cooking time produced higher yellowness values. Most textural variables in a texture profile analysis showed a marked interaction between cooking temperature and time. Samples cooked for 24 h showed significantly lower values for most of the studied textural parameters for all the temperatures considered. Connective tissue granulation at 60 °C and gelation at 70 °C were observed in the SEM micrographs. The sous-vide cooking of lamb loins dramatically reduced microbial population even with the less intense heat treatment studied (60 °C–6 h).  相似文献   

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Dietary fiber incorporation into bread dough systems greatly interferes with protein association and behavior during heating and cooling. The objective of this study was to understand the individual and combined effects of dietary fibers on dough behavior during mixing, overmixing, pasting and gelling using the Mixolab® device. Impact of different commercial dietary fibers (inulin, sugar beet fiber, pea cell wall fiber and pea hull fiber) on wheat dough mixing, pasting and gelling profiles has been investigated. Mixolab® plots indicate that the incorporation of sugar beet fiber into the dough matrix induces the disruption of the viscoelastic system yielding weaker doughs, and it greatly competes for water with starch affecting pasting and gelling. Conversely, inulin in the range tested seems to integrate into the dough increasing its stability. Additionally, the responses acquired with this device were compared with those obtained with other available methodologies, such as the Brabender Farinograph and the Rapid Visco Analyser, to explore its use as a suitable technique for studying fiber-enriched bread dough physical properties. A broad range of correlation between Mixolab® and traditional devices were found.  相似文献   

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Front-of-Pack (FoP) nutrition labels are emerging as a prominent public policy tool for promoting healthy eating. In this study, we question how different FoP nutrition labels ranging from more directive (Nutriscore, NS), to semi-directive (monochromatic Guided Daily Amount, GDA) and non-directive (multiple-traffic lights, MTL), affect perceived visual attention and nutritional quality perception. The visual attention was measured by eye-tracing measures, and nutritional quality by healthiness perception and recommended frequency of consumption. Seventy-six participants (N = 76) were randomly assigned in one of three experimental conditions, where they were asked to give estimates on eight different chocolate snack bars. To test whether participants estimates were accurate, we surveyed fifty-six (N = 56) nutritionists and asked for their assessments of the same group of products. The results showed that Nutriscore required least visual attention in terms of dwell-time, number of fixations, and average fixation duration, followed by MTL and GDA. Participants in NS and MTL condition gave significantly higher estimates of nutritional quality compared to experts' estimates. Most accurate estimates came from products with GDA label. Color-coded fields (MTL) required less visual attention, compared to GDA, without adding to visual efficiency. More directive FoP nutrition labels require less visual attention but lead to inflated estimates of products' nutrition quality in the category of less healthy products. In creating public policies, removing the possibility for consumers to process nutritional information and absolute estimates of products' nutrition quality should not be disregarded.  相似文献   

10.
The drying and rehydration process of conventionally and organically cultivated carrots was studied and the resulting data were fitted to the Pelegs model. Carrots were fluid-bed and halogen dried and after that soaked in water at room temperature. The Pelegs model gave a good prediction of water removal and water uptake in all experiments (R>0,994). During the drying process the Pelegs rate constant (K1) was affected by temperature. K1 values decreased with the increase of the drying temperature. This relation was linear for fluid-bed drying and exponential for halogen drying, which implied a higher impact of the drying temperature on the dehydration kinetics during halogen drying. The lower K1 values for fluid-bed drying suggested higher initial drying rates in comparison with halogen drying at all drying temperatures. The temperature dependence of 1/K1 followed an Arrhenius-type relationship. Both Pelegs rehydration constants (K1 and K2) increased with the increase of the drying temperature. This implied regular decrease of initial rehydration rate and water uptake with the increase of the drying temperature.  相似文献   

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Contact lenses (CLs) designed to deliver medication gradually to the eye are being developed and investigated for the use in ocular drug delivery. The aim of the current research is to determine patients’ acceptance of the use of lenses for ocular drug delivery. In addition, the study aimed to seek the views and perceptions of healthcare professionals (HCPs) on CLs as a method of ocular drug delivery and whether it will be prescribed to treat ocular conditions.This was a cross-sectional survey targeted at patients and HCPs. Two separate questionnaires were created with open-closed ended and multiple response questions, gauging the perceptions and acceptance of CLs as drug delivery tool. The patients’ survey was distributed in John Radcliffe (JR), Oxford and Moorfields eye hospital (MEH), London, UK. The HCPs’ questionnaire was manually distributed and was also devised on Survey Monkey and sent by email to ophthalmologists, optometrists, opticians, GPs and hospital and community pharmacists. The data were analysed using SPSS statistical software and Excel.Over 60% (92/151) of patients would accept the use of CLs for their ocular treatment with the highest acceptance being reported by patients in the age group of 30–49 years old. The most frequently used conventional treatment formulation was eye drops as indicated by 87% (131/151) of the responses. More than half of eye drop users (57%, 75/131) indicated that they would accept using CLs expecting them to reduce the frequency of application of the medicine and be less time consuming. Interestingly, half of HCPs were not aware of CLs as an ocular drug delivery method; nevertheless, a total of 65 HCPs out of the 112 surveyed stated that they would prescribe/dispense CLs to treat ocular disease.  相似文献   

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Structural and textural properties of extruded corn and corn–lentil mixtures were investigated as a result of process conditions, including extrusion temperature (170–230 °C), feed rate (2.52–6.84 kg/h) and feed moisture content (13–19% wb). Lentil was used in mixtures with corn flour at a ratio of 10–50% (legume/corn). Apparent density increased with feed rate, moisture content and material ratio and decreased with temperature, while expansion ratio showed an opposite behavior. Modulus of elasticity increased with feed composition and decreased with extrusion conditions. Number of peaks during compression decreased with extrusion temperature and feed composition. Similar behavior was also found for sensory evaluated structural and textural characteristics. The examination of macrostructure confirmed the effects of extrusion conditions and feed composition on structural and textural properties. The properties correlation revealed critical relationships among instrumental and sensorial characteristics. Hence, simple power model equations were developed, which enable their prediction and consequently the design of extruded snacks with acceptable quality characteristics.  相似文献   

14.
To design and optimize high pressure processes at low temperatures, a quantification of the effects of different processing steps on the food structure is required. Beside pressure-shift freezing, the processes of freezing to ice III and ice V, as well as storage at −27 °C and 250 MPa up to 24 h (metastable liquid state of water) of potato samples were examined. Analyses of the structural changes of the plant tissue included impedance measurements, texture analysis, color measurements and the evaluation of the optical appearance. Storage at subzero temperatures without phase transitions resulted in low membrane damage; however, cell lysis was triggered. Freezing to ice III resulted in the lowest damaging effect on the tissue compared to the other phase transition processes investigated. Samples frozen to ice V and pressure-shift frozen were more deteriorated compared to those frozen to ice III. However, considerable improvements compared to conventional freezing were found. The direction of solid–solid phase transitions (phase transition of ice I to ice III or phase transition of ice III to ice I) influenced the result of high pressure–low temperature processing significantly.Industrial relevanceIt was previously shown that pressure supported phase transitions of ice I like pressure shift freezing are able to preserve the fragile stucture of biological samples like food better than conventional freezing. The present study extends the knowledge of pressure supported phase transitions to a higher pressure domain with the participation of other ice modifications. The authors demonstrate the influences of high pressure phase transitions of water on plant tissue material depending on the processing conditions. The study opens the way to new industrial processing concepts based on high pressure low temperature applications.  相似文献   

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A three-factor–three-level Box–Behnken design was adopted to study the simultaneous effects of two compositional variables (6–8% sago starch and 25–35% sugar) and one processing variable (shearing speed of mixer at 20–50 rpm) on textural and rheological properties of gels. Analysis of variance (ANOVA) was performed to evaluate the potential interactive and quadratic effects between these variables. Sago starch and sugar levels both increased gel stiffness and viscoelasticity. Shearing, on the other hand, reduced gel stiffness and viscoelasticity. Ridge analysis was performed to estimate the values of these variables which maximised and minimised the textural parameters of hardness, gumminess, resilience, cohesiveness, and springiness. Pearson correlations among various rheological and textural properties of gels were studied. The processing conditions that contributed to an optimum gel setting were found at sago starch of level of 7.69%, sugar of 30.29%, and shearing speed of 45.86 rpm.  相似文献   

16.
Brewer’s spent grain (BSG) represents 85?% of brewing industry by-products. Currently, BSG is underutilised as low-value animal fodder. The current study aims to expose additional nutritional and economic benefits of BSG as a food ingredient in wheat breads. The raw material properties were studied revealing that BSG by-product contains (on a w/w) 22.13?% protein (including exceptionally high levels of essential amino acids), 1.13?% minerals, 131.0?mg/L polyphenols, 28.22?% total fibre and 3.6?% essential fatty acids. Additionally, BSG was fermented (BSG SD), using the lactic acid bacteria, Lactobacillus plantarum FST 1.7, to elucidate the benefits of traditional sourdough for processing crude BSG. Fermentation resulted in softer breads with increased springiness. Farinograph results revealed that wheat flour incorporating BSG had increased water absorption. Rheological measurements showed a positively correlated increase in dough resistance in line with BSG or BSG SD incorporation. Supplemented breads had sensory acceptability up to levels of 10?% BSG or BSG SD, resulting in breads comparing favourably with wholemeal breads from a nutritional, technological and textural perspective. Using BSG as a main stream food ingredient would increase the market value of this by-product, thus enhancing its economic potential, a factor that is also discussed.  相似文献   

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Boiled peanuts are preferable as a ready-to-eat healthy snack; however, gamma irradiation as a postharvest treatment of raw peanuts may induce unfavourable food components. Hence, the phytochemical, antioxidant, and the texture of boiled ‘Tainan 9’ peanuts pretreated with gamma irradiation (0, 2.5, 5, and 10 kGy) and stored at 29 ± 2 °C for up to 180 days were investigated. Both gamma irradiation and storage time contributed to testa darkening in raw peanuts. In boiled irradiated products, irradiation doses and storage time affected the moisture content (MC), total proteins, total oil, total soluble sugars, and antioxidant capacity (P ≤ 0.05). Total phenolic and flavonoid contents showed an increase at days 90 and decreased at days 180 across all treatments. A positive correlation was observed among ferric reducing antioxidant power (FRAP), total phenolics, and total flavonoids. Gamma irradiation at 10 kGy led to increase of peroxide value (PV) (P ≤ 0.05), but malondialdehyde (MDA) content was unaffected. Textural properties of boiled irradiated peanuts were soft. As a result, gamma irradiation at 5 kGy is recommended for postharvest treatment of raw peanuts with subsequent storage up to 180 days to obtain the eating quality of boiled peanuts with good phytochemicals and antioxidant properties, which is a challenge for food industry.  相似文献   

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Bread represents a suitable food product for the addition of functional ingredients, such as the cholesterol-lowering dietary fibre oat β-glucan and the prebiotic inulin. Therefore, these soluble fibres were incorporated into wheat as well as gluten-free bread, and their effects on rheological properties of the dough, on bread quality and on crumb microstructure were compared. The level of remaining β-glucan as well as its molecular weight was determined using an enzyme kit and size-exclusion chromatography. The addition of oat β-glucan resulted in a higher water addition level, whereas incorporation of inulin had the opposite effect. Rheological testing showed that the incorporation of oat β-glucan results in a more elastic dough. The baking characteristics mainly affected by fibre addition were volume and crust colour, with inulin increasing and oat β-glucan decreasing loaf-specific volume in the gluten-free breads. Inulin led to a darkening of the crust of both bread types, whereas addition of oat β-glucan resulted in a lighter crust of gluten-free bread. Oat β-glucan softened the crumb of gluten-free bread, but had the opposite effect on wheat bread. Inulin resulted in an increased crumb hardness as well as the rate of staling. Beta-glucan breakdown was more pronounced in wheat bread than in gluten-free bread. The results show that the use of β-glucan to increase the nutritional value of wheat bread is limited due to negative influences on technological properties. However, this soluble fibre is highly suitable for incorporation into gluten-free bread.  相似文献   

19.
The objective of this study was to evaluate the ability of milk infrared spectra to predict blood β-hydroxybutyrate (BHB) concentration for use as a management tool for cow metabolic health on pasture-grazed dairy farms and for large-scale phenotyping for genetic evaluation purposes. The study involved 542 cows (Holstein-Friesian and Holstein-Friesian × Jersey crossbreds), from 2 farms located in the Waikato and Taranaki regions of New Zealand that operated under a seasonal-calving, pasture-based dairy system. Milk infrared spectra were collected once a week during the first 5 wk of lactation. A blood “prick” sample was taken from the ventral labial vein of each cow 3 times a week for the first 5 wk of lactation. The content of BHB in blood was measured immediately using a handheld device. After outlier elimination, 1,910 spectra records and corresponding BHB measures were used for prediction model development. Partial least square regression and partial least squares discriminant analysis were used to develop prediction models for quantitative determination of blood BHB content and for identifying cows with hyperketonemia (HYK). Both quantitative and discriminant predictions were developed using the phenotypes and infrared spectra from two-thirds of the cows (randomly assigned to the calibration set) and tested using the remaining one-third (validation set). A moderate accuracy was obtained for prediction of blood BHB. The coefficient of determination (R2) of the prediction model in calibration was 0.56, with a root mean squared error of prediction of 0.28 mmol/L and a ratio of performance to deviation, calculated as the ratio of the standard deviation of the partial least squares model calibration set to the standard error of prediction, of 1.50. In the validation set, the R2 was 0.50, with root mean squared error of prediction values of 0.32 mmol/L, which resulted in a ratio of performance to deviation of 1.39. When the reference test for HYK was defined as blood concentration of BHB ≥1.2 mmol/L, discriminant models indicated that milk infrared spectra correctly classified 76% of the HYK-positive cows and 82% of the HYK-negative cows. The quantitative models were not able to provide accurate estimates, but they could differentiate between high and low BHB concentrations. Furthermore, the discriminant models allowed the classification of cows with reasonable accuracy. This study indicates that the prediction of blood BHB content or occurrence of HYK from milk spectra is possible with moderate accuracy in pasture-grazed cows and could be used during routine milk testing. Applicability of infrared spectroscopy is not likely suited for obtaining accurate BHB measurements at an individual cow level, but discriminant models might be used in the future as herd-level management tools for classification of cows that are at risk of HYK, whereas quantitative models might provide large-scale phenotypes to be used as an indicator trait for breeding cows with improved metabolic health.  相似文献   

20.
The understanding of what the consumer considers as craftsmanship is a sensitive question in the food sector. Despite food label regulations on this issue having undergone partial harmonisation, revealing what the consumer perceives as a craft food is a feat that has yet to be achieved. Drawing upon a review of literature in the field of consumer research, this investigation addresses this knowledge gap. In the light of the Alphabet Theory framework, the review offers a systematic overview of the motives affecting individuals’ perception of food product craftsmanship, as well as of the key factors affecting consumer behaviour towards craft foods. The findings provide useful insight to add to the body of extant literature and to discuss the possible directions of research. Moreover, the results can also have relevant importance to support legislators in designing appropriate regulations on craft foods.  相似文献   

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