924 resultados para FOOD COMPOSITION
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Objective To develop a height and weight based equation to estimate total body water (TBW) in Sri Lankan children. Methods Cross sectional descriptive study done involving 5–15 year old healthy children. Height and weight were measured. TBW was assessed using isotope dilution method (D2O) and fat free mass (FFM) calculated. Multiple regression analysis was used to develop prediction equation and validated using PRESS statistical technique. Height, weight and sex code (male=1; female=0) were used as prediction variables. Results This study provides height and weight equation for the prediction of TBW in Sri Lankan children. To the best of our knowledge there are no published height weight prediction equations validated on South Asian populations. Conclusion Results of this study need to be affirmed by more studies on other closely related populations by using multicomponent body composition.
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Abstract: Over the years bioelectrical impedance assay (BIA) has gained popularity in the assessment of body composition. However, equations for the prediction of whole body composition use whole body BIA. This study attempts to evaluate the usefulness of segmental BIA in the assessment of whole body composition. A cross sectional descriptive study was conducted at the Professorial Paediatric Unit of Lady Ridgeway Hospital, Colombo, involving 259 (M/F:144/115) 5 to 15 year old healthy children. The height, weight, total and segmental BIA were measured and impedance indices and specific resistivity for the whole body and segments were calculated. Segmental BIA indices showed a significant association with whole body composition measures assessed by total body water (TBW) using the isotope dilution method (D2O). Impedance index was better related to TBW and fat free mass (FFM), while specific resistivity was better related to the fat mass of the body. Regression equations with different combinations of variables showed high predictability of whole body composition. Results of this study showed that segmental BIA can be used as an alternative approach to predict the whole body composition in Sri Lankan children.
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Background: Appetitive traits and food preferences are key determinants of children’s eating patterns but it is unclear how these behaviours relate to one another. This study explores relationships between appetitive traits and preferences for fruits and vegetables, and energy dense, nutrient poor (noncore) foods in two distinct samples of Australian and British preschool children. Methods: This study reports secondary analyses of data from families participating in the British GEMINI cohort study (n=1044) and the control arm of the Australian NOURISH RCT (n=167). Food preferences were assessed by parent-completed questionnaire when children were aged 3-4 years and grouped into three categories; vegetables, fruits and noncore foods. Appetitive traits; enjoyment of food, food responsiveness, satiety responsiveness, slowness in eating, and food fussiness were measured using the Children’s Eating Behaviour Questionnaire when children were 16 months (GEMINI) or 3-4 years (NOURISH). Relationships between appetitive traits and food preferences were explored using adjusted linear regression analyses that controlled for demographic and anthropometric covariates. Results: Vegetable liking was positively associated with enjoyment of food (GEMINI; β=0.20 ± 0.03, p<0.001, NOURISH; β=0.43 ± 0.07, p<0.001) and negatively related to satiety responsiveness (GEMINI; β=-0.19 ± 0.03, p<0.001, NOURISH; β=-0.34 ± 0.08, p<0.001), slowness in eating (GEMINI; β=-0.10 ± 0.03, p=0.002, NOURISH; β=-0.30 ± 0.08, p<0.001) and food fussiness (GEMINI; β=-0.30 ± 0.03, p<0.001, NOURISH; β=-0.60 ± 0.06, p<0.001). Fruit liking was positively associated with enjoyment of food (GEMINI; β=0.18 ± 0.03, p<0.001, NOURISH; β=0.36 ± 0.08, p<0.001), and negatively associated with satiety responsiveness (GEMINI; β=-0.13 ± 0.03, p<0.001, NOURISH; β=-0.24 ± 0.08, p=0.003), food fussiness (GEMINI; β=-0.26 ± 0.03, p<0.001, NOURISH; β=-0.51 ± 0.07, p<0.001) and slowness in eating (GEMINI only; β=-0.09 ± 0.03, p=0.005). Food responsiveness was unrelated to liking for fruits or vegetables in either sample but was positively associated with noncore food preference (GEMINI; β=0.10 ± 0.03, p=0.001, NOURISH; β=0.21 ± 0.08, p=0.010). Conclusion: Appetitive traits linked with lower obesity risk were related to lower liking for fruits and vegetables, while food responsiveness, a trait linked with greater risk of overweight, was uniquely associated with higher liking for noncore foods.
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Objective We examined whether exposure to a greater number of fruits, vegetables, and noncore foods (ie, nutrient poor and high in saturated fats, added sugars, or added salt) at age 14 months was related to children’s preference for and intake of these foods as well as maternal-reported food fussiness and measured child weight status at age 3.7 years. Methods This study reports secondary analyses of longitudinal data from mothers and children (n=340) participating in the NOURISH randomized controlled trial. Exposure was quantified as the number of food items (n=55) tried by a child from specified lists at age 14 months. At age 3.7 years, food preferences, intake patterns, and fussiness (also at age 14 months) were assessed using maternal-completed, established questionnaires. Child weight and length/height were measured by study staff at both age points. Multivariable linear regression models were tested to predict food preferences, intake patterns, fussy eating, and body mass index z score at age 3.7 years adjusting for a range of maternal and child covariates. Results Having tried a greater number of vegetables, fruits, and noncore foods at age 14 months predicted corresponding preferences and higher intakes at age 3.7 years but did not predict child body mass index z score. Adjusting for fussiness at age 14 months, having tried more vegetables at age 14 months was associated with lower fussiness at age 3.7 years. Conclusions These prospective analyses support the hypothesis that early taste and texture experiences influence subsequent food preferences and acceptance. These findings indicate introduction to a variety of fruits and vegetables and limited noncore food exposure from an early age are important strategies to improve later diet quality.
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Intermittent microwave convective drying (IMCD) is an advanced technology that improves both energy efficiency and food quality in drying. Modelling of IMCD is essential to understand the physics of this advanced drying process and to optimize the microwave power level and intermittency during drying. However, there is still a lack of modelling studies dedicated to IMCD. In this study, a mathematical model for IMCD was developed and validated with experimental data. The model showed that the interior temperature of the material was higher than the surface in IMCD, and that the temperatures fluctuated and redistributed due to the intermittency of the microwave power. This redistribution of temperature could significantly contribute to the improvement of product quality during IMCD. Limitations when using Lambert's Law for microwave heat generation were identified and discussed.
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Asthma prevalence in children has remained relatively constant in many Western countries, but hospital admissions for younger age groups have increased over time.1 Although the role of outdoor aeroallergens as triggers for asthma exacerbations requiring hospitalization in children and adolescents is complex, there is evidence that increasing concentrations of grass pollen are associated with an increased risk of asthma exacerbations in children.2 Human rhinovirus (HRV) infections are implicated in most of the serious asthma exacerbations in school-age children.3 In previous research, HRV infections and aeroallergen exposure have usually been studied independently. To our knowledge, only 1 study has examined interactions between these 2 factors,4 but lack of power prevented any meaningful interpretation...
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Contemporary food systems promote the consumption of highly processed foods of limited nutrition, contributing to overweight and obesity, diet-related disease and significant financial burden on healthcare systems. In part, this has resulted from highly successful design, development and marketing strategies for processed foods. The successful application of such strategies to healthy food options, and the services and business plans that accompany them, could assist in enhancing health and alleviating burden on health care systems. Product designers have long been aware of the importance of intertwining emotional experiences with new products. However, a lack of theoretical precision exists for applying emotional design beyond food products, to the food systems, services and business models that drive them. This article explores emotional design within the context of food and food systems and proposes a new concept – Emotional Food Design (EFD), through which emotional design is integrated across levels of a food system. EFD complements the dominating deductive view of food systems research with an abductive iterative design approach contextualized within the creation of new food products, services and business models and their associated emotional attachments. This paper concludes by outlining what EFD can offer to reorient food systems to successfully promote healthy eating.
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The concept of energy gap(s) is useful for understanding the consequence of a small daily, weekly, or monthly positive energy balance and the inconspicuous shift in weight gain ultimately leading to overweight and obesity. Energy gap is a dynamic concept: an initial positive energy gap incurred via an increase in energy intake (or a decrease in physical activity) is not constant, may fade out with time if the initial conditions are maintained, and depends on the 'efficiency' with which the readjustment of the energy imbalance gap occurs with time. The metabolic response to an energy imbalance gap and the magnitude of the energy gap(s) can be estimated by at least two methods, i.e. i) assessment by longitudinal overfeeding studies, imposing (by design) an initial positive energy imbalance gap; ii) retrospective assessment based on epidemiological surveys, whereby the accumulated endogenous energy storage per unit of time is calculated from the change in body weight and body composition. In order to illustrate the difficulty of accurately assessing an energy gap we have used, as an illustrative example, a recent epidemiological study which tracked changes in total energy intake (estimated by gross food availability) and body weight over 3 decades in the US, combined with total energy expenditure prediction from body weight using doubly labelled water data. At the population level, the study attempted to assess the cause of the energy gap purported to be entirely due to increased food intake. Based on an estimate of change in energy intake judged to be more reliable (i.e. in the same study population) and together with calculations of simple energetic indices, our analysis suggests that conclusions about the fundamental causes of obesity development in a population (excess intake vs. low physical activity or both) is clouded by a high level of uncertainty.
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Change in temperature is often a major environmental factor in triggering waterborne disease outbreaks. Previous research has revealed temporal and spatial patterns of bacterial population in several aquatic ecosystems. To date, very little information is available on aquaculture environment. Here, we assessed environmental temperature effects on bacterial community composition in freshwater aquaculture system farming of Litopenaeus vannamei (FASFL). Water samples were collected over a one-year period, and aquatic bacteria were characterized by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rDNA pyrosequencing. Resulting DGGE fingerprints revealed a specific and dynamic bacterial population structure with considerable variation over the seasonal change, suggesting that environmental temperature was a key driver of bacterial population in the FASFL. Pyrosequencing data further demonstrated substantial difference in bacterial community composition between the water at higher (WHT) and at lower (WLT) temperatures in the FASFL. Actinobacteria, Proteobacteria and Bacteroidetes were the highest abundant phyla in the FASFL, however, a large number of unclassified bacteria contributed the most to the observed variation in phylogenetic diversity. The WHT harbored remarkably higher diversity and richness in bacterial composition at genus and species levels when compared to the WLT. Some potential pathogenenic species were identified in both WHT and WLT, providing data in support of aquatic animal health management in the aquaculture industry.
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Species identification based on short sequences of DNA markers, that is, DNA barcoding, has emerged as an integral part of modern taxonomy. However, software for the analysis of large and multilocus barcoding data sets is scarce. The Basic Local Alignment Search Tool (BLAST) is currently the fastest tool capable of handling large databases (e.g. >5000 sequences), but its accuracy is a concern and has been criticized for its local optimization. However, current more accurate software requires sequence alignment or complex calculations, which are time-consuming when dealing with large data sets during data preprocessing or during the search stage. Therefore, it is imperative to develop a practical program for both accurate and scalable species identification for DNA barcoding. In this context, we present VIP Barcoding: a user-friendly software in graphical user interface for rapid DNA barcoding. It adopts a hybrid, two-stage algorithm. First, an alignment-free composition vector (CV) method is utilized to reduce searching space by screening a reference database. The alignment-based K2P distance nearest-neighbour method is then employed to analyse the smaller data set generated in the first stage. In comparison with other software, we demonstrate that VIP Barcoding has (i) higher accuracy than Blastn and several alignment-free methods and (ii) higher scalability than alignment-based distance methods and character-based methods. These results suggest that this platform is able to deal with both large-scale and multilocus barcoding data with accuracy and can contribute to DNA barcoding for modern taxonomy. VIP Barcoding is free and available at http://msl.sls.cuhk.edu.hk/vipbarcoding/.
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Objective To examine whether psychosocial factors mediate (explain) the association between socioeconomic position and takeaway food consumption. Design A cross-sectional postal survey conducted in 2009. Setting Participants reported their usual consumption of 22 takeaway food items, and these were grouped into a “healthy” and “less healthy” index based on each items' nutritional properties. Principal Components Analysis was used to derive three psychosocial scales that measured beliefs about the relationship between diet and health (α = 0.73), and perceptions about the value (α = 0.79) and pleasure (α = 0.61) of takeaway food. A nutrition knowledge index was also used. Socioeconomic position was measured by highest attained education level. Subjects Randomly selected adults (n = 1,500) aged between 25–64 years in Brisbane, Australia (response rate = 63.7%, N = 903). Results Compared with those with a bachelor degree or higher, participants with a diploma level of education were more likely to consume “healthy” takeaway food (p = 0.023) whereas the least educated (high school only) were more likely to consume “less healthy” choices (p = 0.002). The least educated were less likely to believe in a relationship between diet and health (p<0.001), and more likely to have lower nutritional knowledge compared with their highly educated counterparts (p<0.001). Education differences in beliefs about the relationship between diet and health partly and significantly mediated the association between education and “healthy” takeaway food consumption. Diet- and health-related beliefs and nutritional knowledge partly and significantly mediated the education differences in “less healthy” takeaway food consumption. Conclusions Interventions that target beliefs about the relationship between diet and health, and nutritional knowledge may reduce socioeconomic differences in takeaway food consumption, particularly for “less healthy” options.
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A simple one-step electrodeposition method was used to construct a glassy carbon electrode (GCE), which has been modified with Cu doped gold nanoparticles (GNPs), i.e. a Cu@AuNPs/GCE. This electrode was characterized with the use of scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The eugenol was electrocatalytically oxidized at the Cu@AuNPs/GCE. At this electrode, in comparison with the behavior at the GCE alone, the corresponding oxidation peak current was enhanced and the shift of the oxidation potentials to lower values was observed. Electrochemical behavior of eugenol at the Cu@AuNPs/GCE was investigated with the use of the cyclic voltammetry (CV) technique, and additionally, in order to confirm the electrochemical reaction mechanism for o-methoxy phenols, CVs for catechol, guaiacol and vanillin were investigated consecutively. Based on this work, an electrochemical reaction mechanism for o-methoxy phenols was suggested, and in addition, the above Cu@AuNPs/GCE was successfully employed for the analysis of eugenol in food samples.
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Biodiesels produced from different feedstocks usually have wide variations in their fatty acid methyl ester (FAME) so that their physical properties and chemical composition are also different. The aim of this study is to investigate the effect of the physical properties and chemical composition of biodiesels on engine exhaust particle emissions. Alongside with neat diesel, four biodiesels with variations in carbon chain length and degree of unsaturation have been used at three blending ratios (B100, B50, B20) in a common rail engine. It is found that particle emission increased with the increase of carbon chain length. However, for similar carbon chain length, particle emissions from biodiesel having relatively high average unsaturation are found to be slightly less than that of low average unsaturation. Particle size is also found to be dependent on fuel type. The fuel or fuel mix responsible for higher particle mass (PM) and particle number (PN) emissions is also found responsible for larger particle median size. Particle emissions reduced consistently with fuel oxygen content regardless of the proportion of biodiesel in the blends, whereas it increased with fuel viscosity and surface tension only for higher diesel–biodiesel blend percentages (B100, B50). However, since fuel oxygen content increases with the decreasing carbon chain length, it is not clear which of these factors drives the lower particle emission. Overall, it is evident from the results presented here that chemical composition of biodiesel is more important than its physical properties in controlling exhaust particle emissions.
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Objective: To develop bioelectrical impedance analysis (BIA) equations to predict total body water (TBW) and fat-free mass (FFM) of Sri Lankan children. Subjects/Methods: Data were collected from 5- to 15-year-old healthy children. They were randomly assigned to validation (M/F: 105/83) and cross-validation (M/F: 53/41) groups. Height, weight and BIA were measured. TBW was assessed using isotope dilution method (D2 O). Multiple regression analysis was used to develop preliminary equations and cross-validated on an independent group. Final prediction equation was constructed combining the two groups and validated by PRESS (prediction of sum of squares) statistics. Impedance index (height2/impedance; cm2/Ω), weight and sex code (male = 1; female = 0) were used as variables. Results: Independent variables of the final prediction equation for TBW were able to predict 86.3% of variance with root means-squared error (RMSE) of 2.1l. PRESS statistics was 2.1l with press residuals of 1.2l. Independent variables were able to predict 86.9% of variance of FFM with RMSE of 2.7 kg. PRESS statistics was 2.8 kg with press residuals of 1.4 kg. Bland Altman technique showed that the majority of the residuals were within mean bias±1.96 s.d. Conclusions: Results of this study provide BIA equation for the prediction of TBW and FFM in Sri Lankan children. To the best of our knowledge there are no published BIA prediction equations validated on South Asian populations. Results of this study need to be affirmed by more studies on other closely related populations by using multi-component body composition assessment.
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Background: Eosinophilic esophagitis (EE) is an emerging condition where patients commonly present with symptoms of gastroesophageal reflux disease and fail to respond adequately to anti-reflux therapy. Food allergy is currently recognized as the main immunological cause of EE; recent evidence suggests an etiological role for inhalant allergens. The presence of EE appears to be associated with other atopic illnesses. Objectives: To report the sensitization profile of both food and inhalant allergens in our EE patient cohort in relation to age, and to profile the prevalence of other allergic conditions in patients with EE. Method: The study prospectively analyzed allergen sensitization profiles using skin prick tests to common food allergens and inhalant allergens in 45 children with EE. Patch testing to common food allergens was performed on 33 patients in the same cohort. Comorbidity of atopic eczema, asthma, allergic rhinitis and anaphylaxis were obtained from patient history. Results: Younger patients with EE showed more IgE and patch sensitization to foods while older patients showed greater IgE sensitization to inhalant allergens. The prevalence of atopic eczema, allergic rhinitis and asthma was significantly increased in our EE cohort compared with the general Australian population. A total of 24% of our cohort of patients with EE had a history of anaphylaxis. Conclusion: In children with EE, the sensitization to inhalant allergens increases with age, particularly after 4 years. Also, specific enquiry about severe food reactions in patients presenting with EE is strongly recommended as it appears this patient group has a high incidence of anaphylaxis. © 2007 The Authors.