107 resultados para 090801 Food Chemistry and Molecular Gastronomy (excl. Wine)


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pH-detachable poly(styrene) brushes formed on indium−tin oxide (ITO) glass substrates using metal complex chemistry and reversible addition−fragmentation chain transfer (RAFT) polymerization was described. These pH-detachable polymeric brushes were generated using both “graft-from” and “graft-to” methodologies. The methodologies involved either the surface self-assembly of catechol-functional RAFT agents (graft-from) or catechol-terminal polymer chains (graft-to) onto the ITO substrate via titanium−diol coordination. The stepwise functionalization of the ITO glass surfaces was characterized successfully using X-ray photoelectron spectroscopy (XPS) and contact angle measurement. Poly(styrene) brushes generated using the “graft-from” method were denser than those generated using the “graft-to” method, as exemplified by atom force microscopy (AFM) and quantified using cyclic voltammetry. Poly(styrene) brushes assembled using both methods could be detached easily by manipulating the pH of the brush environment. Cyclic voltammetry was utilized to calculate precisely the surface coverage of the RAFT functionality and polymeric brush density.

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While weight, health, diet, and exercise receive constant media and governmental attention, relatively little is known about the influence of body image in the food consumption process. Moreover, there is general consensus within the literature that the factors that influence consumption behavior can have a different impact on different consumer groups. Body image, for example, is perceived to be a modulating force in the consumption behavior of young women. As a result, there is a need for an empirically based understanding of the factors that influence food-purchasing and consumption behavior among this group. Studies have investigated the links between perceived body image and food-purchasing behavior. In 18- to 30-year-old women, it has been shown that personal values, vanity, physical health, and perceived body image were major factors of influence in the purchasing and consumption decisions of this group. It was also identified that respondents across these studies engaged in healthy and unhealthy consumption practices in order to achieve their perceived body image ideals.

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An inclusion host-guest complex between β-cyclodextrin (β-CD) and L-phenylalanine (LPhe) was investigated using 1H nuclear magnetic resonance spectroscopy and molecular docking techniques. 1H chemical shift changes of β-CD were used to calculate the stability constant (Kstb) of the complex. On the basis of the Hildebrand-Benesi method, the Kstb of the 1:1 complex in D2O solution at 300 K, pD 7.6 was of 25.5 M-1, implying a fast intermolecular exchange rate process. Interestingly, docking simulation indicates the toroidal space can be occupied by L-Phe with two favorable arrangements. For the predicted model with the higher probability score, the L-Phe aromatic ring is facing to the secondary hydroxyl groups of β-CD. Results from NMR and docking simulation are in good agreement with the x-ray structures of β-CD/L-phenylalanine derivatives.

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This Account covers research dating from the early 1960s in the field of low-melting molten salts and hydrates,which has recently become popular under the rubric of “ionic liquids”. It covers understanding gained in the principal author’s laboratories (initially in Australia, but mostly in the U.S.A.) from spectroscopic, dynamic, and thermodynamic studies and includes recent applications of this understanding in the fields of energy conversion and biopreservation. Both protic and aprotic varieties of ionic liquids are included, but recent studies have focused on the protic class because of the special applications made possible by the highly variable proton activities available in these liquids.

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A passion for food that is understood in certain ways – slow, organic, not industrialised – plays a central role in the drama of the successful and popular Jamie’s Kitchen (2002) and Jamie’s Kitchen Australia (2006). Large parts of the drama in these shows revolve around an apparent lack of passion that is displayed by the marginalised, unemployed young people that are the central characters in this story. In this paper I examine the ways in which these accounts of food, passion, and the training of marginalised young people expose some of the challenges and opportunities faced by marginalised young people as they seek to transition into the uncertain and risky labour markets of 21st century capitalism. I argue that Michel Foucault’s (1988) concept of technologies of the self enables us to understand passion, and its particular manifestations in Jamie’s Kitchen, and in the training of marginalised young people, as a powerful technology of self transformation. The drama of Jamie’s Kitchen suggests that as a technology of the self passion for food promises to provide precarious, possibly temporary, forms of salvation, meaning and purpose for the young people engaged in the Fifteen Foundation’s social enterprise transitional labour market program.

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Interfacial chemistry and adhesion between titanium dioxide (TiO2) nanotube layers and titanium (Ti) substrates were studied in this Article. TiO2 nanotube layers were produced on pure Ti by anodization and annealed in air for different time durations. The adhesion of the TiO2 nanotube layers was then investigated by Rockwell C indentation test. Results show that adhesion of TiO2 nanotube layers improved with the extension of annealing time. This improvement in adhesion of TiO2 nanotube layers was analyzed from the viewpoint of interfacial chemistry using energy dispersive X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS). It suggests that more Ti-O bonds formed in the interface after annealing, and this led to the improved adhesion of the TiO2 nanoube layers.

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This study extends McPhie et al. (2011)'s [Maternal correlates of preschool child eating behaviours and body mass index: A cross-sectional study. International Journal of Pediatric Obesity, Early Online, 1–5.] McPhie et al. (2011)’s cross-sectional research, by prospectively evaluating maternal child-feeding practices, parenting style and mother–child interactions as predictors of child-eating behaviours, food habits and weight. A sample of 117 mothers of preschoolers (63 girls, 54 boys) participated at two time-points, Time 1 (T1) and Time 2 (T2), 12 months apart. Results from the two path models revealed maternal pressure to eat at T1 positively predicted change in child enjoyment of food. Maternal warmth at T1 negatively predicted child unhealthy food habits at T2. At T1, family income and maternal control negatively predicted change in child body mass index z-scores (BMIz); maternal pressure to eat at T1 also positively predicted change in child BMIz. There were significant results specific to each model. Both final path models provided an adequate fit. Our findings suggest childhood obesity is predicted by a complex interplay of demographic, maternal and child variables.

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The present study examined associations between food marketing exposure and adolescents’ food choices and reported consumption of energy-dense and nutrient-poor (EDNP) foods. A cross-sectional survey of 12,188 Australian secondary students aged 12–17 years was conducted, using a web-based self-report questionnaire. Measures included students’ level of exposure to commercial television and non-broadcast types of food marketing, whether they had tried a new product or requested a product they had seen advertised, and their reported consumption of fast food, sugary drinks and sweet and salty snacks. Results indicated greater exposure to commercial television, print/transport/school food marketing and digital food marketing were all independently associated with students’ food choices. High commercial television viewers (>2 h/day) were more likely to report higher consumption of EDNP foods (ORs ranged from 1.31 for fast food to 1.91 for sweet snacks). Some associations between digital food marketing exposure and students’ eating behaviors were found; however, print/transport/school food marketing was only related to sweet snack consumption. These study results suggest that cumulative exposure to television food advertising and other food marketing sources are positively linked to adolescents’ food choices and eating behaviors. Policy changes to restrict food marketing to young people should include both television and non-broadcast media.

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Background/objectives: Takeaway food consumption is positively associated with adiposity. Little is known about the associations with other cardio-metabolic risk factors. This study aimed to determine whether takeaway food consumption is associated with fasting glucose, insulin, lipids, homeostasis model assessment (HOMA) and blood pressure.

Subjects/methods:
A national sample of 1896, 26–36 year olds completed a questionnaire on socio-demographics, takeaway food consumption, physical activity and sedentary behaviour. Waist circumference and blood pressure were measured, and a fasting blood sample was taken. For this analysis, takeaway food consumption was dichotomised to once a week or less and twice a week or more. Linear regression was used to calculate differences in the adjusted mean values for fasting lipids, glucose, insulin, HOMA and blood pressure. Models were adjusted for age, employment status, leisure time physical activity and TV viewing.

Results:
Compared with women who ate takeaway once a week or less, women who ate takeaway twice a week or more had significantly higher adjusted mean fasting glucose (4.82 vs 4.88 mmol/l, respectively; P=0.045), higher HOMA scores (1.27 vs 1.40, respectively, P=0.034) and tended to have a higher mean fasting insulin (5.95 vs 6.45 mU/l, respectively, P=0.054). Similar associations were observed for men for fasting insulin and HOMA score, but the differences were not statistically significant. For both women and men adjustment for waist circumference attenuated the associations.

Conclusion: Consuming takeaway food at least twice a week was associated with cardio-metabolic risk factors in women but less so in men. The effect of takeaway food consumption was attenuated when adjusted for obesity.

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Glycogen plays a major role in supporting the energy demands of skeletal muscles during high intensity exercise. Despite its importance, the amount of glycogen stored in skeletal muscles is so small that a large fraction of it can be depleted in response to a single bout of high intensity exercise. For this reason, it is generally recommended to ingest food after exercise to replenish rapidly muscle glycogen stores, otherwise one's ability to engage in high intensity activity might be compromised. But what if food is not available? It is now well established that, even in the absence of food intake, skeletal muscles have the capacity to replenish some of their glycogen at the expense of endogenous carbon sources such as lactate. This is facilitated, in part, by the transient dephosphorylation-mediated activation of glycogen synthase and inhibition of glycogen phosphorylase. There is also evidence that muscle glycogen synthesis occurs even under conditions conducive to an increased oxidation of lactate post-exercise, such as during active recovery from high intensity exercise. Indeed, although during active recovery glycogen resynthesis is impaired in skeletal muscle as a whole because of increased lactate oxidation, muscle glycogen stores are replenished in Type IIa and IIb fibers while being broken down in Type I fibers of active muscles. This unique ability of Type II fibers to replenish their glycogen stores during exercise should not come as a surprise given the advantages in maintaining adequate muscle glycogen stores in those fibers that play a major role in fight or flight responses.