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1

Weir, Ruth Roberta. "Cow's milk : a potential vehicle for vitamin D enrichment and fortification". Thesis, Ulster University, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.706464.

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Evidence of both low dietary intakes of vitamin D and poor vitamin D status are frequently reported within the literature, including that from nationally representative population surveys in the UK and Ireland. With this evidence in mind, it is clear that novel food-based strategies are required to help the UK population meet the recently revised recommended nutrient intakes (RNIs) for vitamin D. There is increasing evidence to support the efficacy of dairy fortification to increase vitamin D intakes. To-date, however, limited research has been conducted outside the US, Canada and Scandinavia, and pasteurised cows’ milk as a vehicle for such fortification is rarely considered in research studies, with ultra-high temperature milk and milk powder preferred. Therefore, the aim of this thesis was to evaluate the potential o f cows’ milk to increase the dietary vitamin D intake and vitamin D status of consumers. An additional study was also incorporated to validate a vitamin D food frequency questionnaire, which is useful for assessing habitual intake rather than relying on 3-4 day food records. Following the development of a HPLC method to quantify vitamin D3 within milk, analysis of monthly milk samples collected from two processors in Northern Ireland over a 1-year period revealed higher vitamin D3 concentrations in whole milk than those currently listed in food composition tables. Although exposing dairy cattle (n 32) to supplemental UVB light for longer than 8-weeks may be required to significantly increase the vitamin D content of the milk naturally produced, results from a 24-week randomised controlled trial in healthy adults (n 52) demonstrated that vitamin D3 fortified milk (2pg/100g) was as effective as supplemental vitamin D3 at increasing vitamin D status. A dietary modelling scenario supported that fortification of cows’ milk with vitamin D (up to this level; 2gg/100g) could be an effective strategy to increase vitamin D intakes by approximately 2-fold across the population. Consequently, such fortification would also help a larger proportion of the population meet the new RNI, without an individual exceeding the tolerable upper limits, for vitamin D. Overall, this research has demonstrated the efficacy of fresh cows’ milk as a vehicle for either mandatory or voluntary vitamin D fortification (with or without additional dietary supplementation) to help consumers meet the revised requirements and tackle the problem of vitamin D deficiency at the population level.
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2

Laillou, Arnaud. "Vitamins and minerals deficiencies - From epidemiology to food fortification strategy : Vietnam case study". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20041/document.

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Contexte: L'enrichissement des aliments est une stratégie efficace pour lutter contre les carences en micronutriments. Toutefois, il existe de nombreuses étapes critiques, tels que l'évaluation des besoins de la population, l'obtention de l'appui du gouvernement et de l'industrie, le choix du véhicule alimentaire, la sélection des bons micronutriments (s) et son dosage, et enfin le suivi. Objectif: Cette thèse évalue et de discute les défis de l'enrichissement des aliments au Vietnam. Méthodologie: Les méthodes suivantes ont été utilisées: une étude transversale, une enquête sur la consommation, une étude d'impact, une étude de stabilité, une étude coût-conséquences, deux revues de littérature, une étude de validation, et les leçons tirées de programmes d'enrichissement financés par GAIN. Résultats: Les carences en micronutriments chez les femmes et les enfants au Vietnam sont encore très répandues et se chevauchent souvent. Bien qu'il n'y ait pas de consensus sur le meilleur indicateur pour déterminer le statut en zinc, la prévalence du déficit en zinc semble être élevée par example. De nombreuses initiatives d'enrichissement ont montré que le soutien du gouvernement et de l'industrie est essentiel pour réussir. Le gouvernement vietnamien a reconnu la nécessité de lutter contre les carences en micronutriments. Les véhicules appropriés pour l'enrichissement des aliments au Vietnam sont les huiles végétales et le riz, ainsi que la sauce de poisson, la sauce soja, les bouillons cubes et les aliments de complément. Cependant, il y a des questions qui doivent être soigneusement étudiés, tels que le niveau de peroxyde dans l'huile, la présence d'inhibiteurs de l'absorption du fer, ou le risque de sédimentation dans les sauces. Lors de l'ajout de micronutriments aux aliments, des facteurs tels que les coûts, la qualité et la sécurité doivent être pris en considération. Enfin, l'enrichissement doit être soigneusement surveillés pour s'assurer de la qualité et de surveiller les effets sur la santé de la population. Conclusion: Avant que la fortification des aliments puisse être mise en œuvre et être efficace au Vietnam, une série de défis devront être surmontés
Background: Food fortification is an effective strategy to combat micronutrient deficiencies. However, there are many critical steps, such as assessing the population's needs, obtaining support from the government and industries, choosing the food vehicle, selecting the right micronutrient(s) and the dosage and finally monitoring. Objective: The overall objective of this thesis is to assess and discuss the challenges of food fortification in Vietnam. Methodology: The following methods were used: a cross-sectional study, a consumption survey, an impact study, a stability study, a cost-implication study, two literature reviews, a validation study, and lessons learned from GAIN funded fortification programs. Results: Micronutrient deficiencies in women and children in Vietnam are still widespread and often overlap. Although there is no consensus on which indicator is best to use to determine zinc status, zinc deficiency prevalence seems to be high. Numerous fortification initiatives have shown that the support from the government and the industry is essential in order to be successful. The Vietnamese government has recognized the need to fight micronutrient deficiencies. Suitable food vehicles for fortification in Vietnam are vegetable oil and rice, as well as fish sauce, soy sauce, wheat flour and possibly flavoring powders and complementary foods. However, there are issues that need to be carefully studied, such as the peroxide level in the oil, the presence of absorption inhibitors in the flour, or the risk of sedimentation in sauces. When adding micronutrients to foods, factors such as costs, quality and safety need to be considered. Finally, fortification needs to be carefully monitored to assure quality and to supervise the effect on the population's health. Conclusion: Before food fortification can be implemented and be effective in Vietnam, a series of challenges will need to be overcome
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3

Allen, R. E. "Would fortification of more foods with vitamin D improve vitamin D intakes and status of groups at risk of deficiency in the UK?" Thesis, London School of Hygiene and Tropical Medicine (University of London), 2013. http://researchonline.lshtm.ac.uk/2026583/.

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Groups of the UK population have poor vitamin D status, particularly those with low sun exposure and/or poor dietary intake. This study looked at the impact of fortifying more foods with vitamin D in the UK on population vitamin D intakes and status. It included: • A systematic review, which found that consumption of a wide variety of foods (including milk, orange juice and bread) fortified with vitamin D can improve vitamin D status; and that national schemes have been effective at improving status of some, but not all groups of the target population. • An update of the vitamin D content of fortified foods and supplements within the National Diet and Nutrition Survey (NONS) Nutrient Databank, which increased current population vitamin D intakes by 3%. Consideration of a standard level of 'overage' applied during fortification increased population intakes by a further 3%. • A computer-based data processing exercise to simulate the effect of fortifying flour and milk with vitamin D using NONS data. At 10µg vitamin D per 100g flour, the proportion of 'at risk' groups with vitamin D intakes below the UK Reference Nutrient Intake (RNI) was reduced from a current level of 97% to 53%, without anyone exceeding the European Tolerable Upper Intake Level (UL) for vitamin D. Fortification of flour at this level improved intakes across all socio-economic groups and was found to be more effective than fortification of milk, as well as simultaneous fortification of milk and flour. Fortification therefore provides an opportunity for improving vitamin 0 intakes and status in the UK However, there remains much uncertainty surrounding vitamin D, in particular around intake and status levels required for optimum health and the analytical methods used to determine these. Further research is therefore recommended prior to introducing a national scheme to fortify with vitamin D in the UK.
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4

Mooney, Kathleen Marie. "Homocysteine and B vitamins : interventions to assess the effects of B vitamin status and to propose public health strategies for folic acid fortification". Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437484.

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5

Askin, Nadina. "Intake and status of vitamin B12 in healthy younger and older adults : implications for food fortification policy". Thesis, Ulster University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529554.

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6

Mutetikka, David B. "Effect of pasture, confinement and diet fortification of vitamin E and selenium on reproducing gilts and their progeny /". The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487841975358942.

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7

Neves, Daniela Andrade 1988. "Bioacessibilidade in vitro do ácido fólico em pão francês e avaliação de sua estabilidade térmica". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254317.

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Orientadores: Helena Teixeira Godoy, Giovanna Pisanelli Rodrigues de Oliveira
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-23T09:26:52Z (GMT). No. of bitstreams: 1 Neves_DanielaAndrade_M.pdf: 1283645 bytes, checksum: 04bc54a00f7c9c30f4f77c52b62a51c1 (MD5) Previous issue date: 2013
Resumo: A bioacessibilidade é a proporção de um composto ingerido que apresenta-se disponível no intestino para ser absorvido. A verificação da bioacessibilidade do ácido fólico presente em amostras de pão francês produzidos com farinha de trigo fortificada foi realizada através da simulação in vitro da digestão, o que permite a avaliação da eficiência do processo de fortificação da farinha de trigo. O teor de ácido fólico das amostras de farinha de trigo, pão francês e dos extratos obtidos a partir da simulação da digestão foram determinados por cromatografia líquida de ultra performance (UPLC), e em seguida, foram calculadas as retenções do ácido fólico em cada uma das amostras e extratos. Para a verificação da influência da temperatura e tempo de aquecimento na degradação de amostras de padrão de ácido fólico livre e microencapsulado foram realizadas análises térmica diferencial e termogravimétrica (ATD-TG) e difração de raios-X (DRX). Os resultados mostraram que o ácido fólico apresentou retenção de 85% e aproximadamente 70% nas etapas de homogeneização e assamento do pão francês, respectivamente, enquanto que a bioacessibilidade do ácido fólico foi de 100% nas amostras analisadas. As amostras de padrão de ácido fólico apresentaram total degradação após exposição a 155°C por 35 min e 175°C por 15 min. Já o padrão de ácido fólico microencapsulado apresentou completa decomposição a 100°C por 15min. Assim, pode-se concluir que o processo de enriquecimento das farinhas de trigo com ácido fólico, no que diz respeito ao fabrico de pães francês se mostra eficiente e que novas técnicas de recobrimento e técnicas de microencapsulamento devem ser estudadas para poderem ser aplicadas ao ácido fólico
Abstract: Bioaccessibility is the proportion of a compound ingested that is available to be absorbed. The bioaccessibility of folic acid in bread samples made with fortified wheat flour was carried out through the in vitro simulation of the digestion. This vitamin concentration in the flour, bread extracts and in the extracts obtained by de digestion simulation were measured by ultra-performance liquid chromatography (UPLC). Then the folic acid retention was calculated for each sample. The influence of temperature and time in the degradation of free and microencapsulated folic acid standard during a heating process were determined by a thermogravimetric and differential thermal analysis (TG-DTA) and X-ray diffraction (DRX). The results showed that folic acid retention was 85% and near 70% after the flour homogenization and the bread baking, respectively. Even though there were losses during the bread production the folic acid was 100% bioaccessible in the bread samples. The free folic acid standards samples presented total degradation after 35 min at 155°C and 15 min at 175°C exposition. However, the microencapsulated folic acid standards showed a complete degradation under 100°C for 15 min. Thus, it is conclude that in bread fabrication the wheat flour fortification process with folic acid is efficient and that new coating and microencapsulation techniques must be studied in order to be applied to folic acid
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
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8

Hau, Rodney, e s3016872@student rmit edu au. "The analysis and stability of microencapsulated folic acid during the processing and preparation of instant Asian noodles". RMIT University. Applied Sciences, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091006.120940.

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Fortification of instant Asian noodles with folic acid has the potential to enhance dietary folate intakes. Recent studies show folate deficiency is prevalent in many countries. Furthermore, this vitamin is unstable upon exposure to light, air, heat and extreme conditions of acidity and alkalinity. Internationally, folate in foods has traditionally been analysed by a microbiological assay, however, due to the extensive time required for sample preparation and analysis, alternative procedures for analysis require consideration. The aims of the current study have been to investigate the stability of added folic acid in fortified instant fried noodles by analytical methods of capillary electrophoresis and reversed-phase HPLC. Additionally, procedures for the microencapsulation of folic acid by spray drying have been evaluated along with their significance in increasing the stability of the vitamin during processing and boiling of instant noodles. Optimisation of capillary electrophoretic conditions showed that the maximum response of folic acid relative to an internal standard was achieved using various concentrations of phosphate and borate. Analytical parameters including the effects of pH, voltage and temperature were studied along with enzymatic treatments for liberation of folic acid from the noodle matrix based. Higher recoveries were obtained using the enzymes however these exceeded 100% due to sample matrix interference. Standard addition or internal calibration were both effective in correcting for matrix interferences. Comparative investigations with reversed-phase HPLC confirmed the results obtained with the capillary electrophoresis. Using either a phosphate based buffer in conjunction with an ion-pairing agent at alkaline pH or an acidic mobile phase, the results attained were in good agreement as folic acid exhibited excellent stability under typical processing conditions. Various food approved hydrocolloids were evaluated for encapsulation of folic acid by spray drying. Incorporation of the microcapsules into formulations of instant fried noodles showed that after boiling the folic acid was chemically degraded to some extent and leaching also occurred. The microcapsules exhibited similar properties regardless of the binding agent used, with losses still occurring during the boiling stage. In order to enhance the structural integrity of the spray dried microcapsules, CaCl2 was used as a cross-linking agent for capsules prepared using alginate or pectin binding agents. Considerable increases in retention of core material were observed as the network exhibited a reduction in swelling and hydration, and subsequently a decrease in the release of folic acid. In summary, capillary electrophoresis and reversed-phase HPLC provided excellent separation and good quantitatation of added folic acid in instant Asian noodles. Excellent resolution was obtained between the sample matrix interference of instant noodles and the analysed vitamin. Folic acid displayed high stability throughout the processing of instant noodles whereas there was consistent evidence that unencapsulated folic acid was degraded during boiling. Microencapsulation of folic acid with combinations of alginate and pectin as the binding agents, proved to be effective in maintaining folic acid stability when calcium treatment was performed after spray drying. These findings provide an effective way to retain folic acid used in fortifying Asian instant noodles.
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9

Lee, Garth Anthony. "Blend Uniformity and Vitamin Stability in Dairy-Based Foods Fortified with Lipid-Encapsulated Ferrous Sulfate". BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8138.

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Homogeneity of powder blends is an important metric for industrial applications in fortified dairy foods including commercial pediatric nutrition products. Product development practices evaluating physical properties and nutrient stability performance are reliant on blending parameters that deliver a uniform powder at both the pilot and commercial scale. Quantities of individual micronutrients in finished products are particularly critical for formulated infant foods. The two preliminary phases of this study focused on developing a simple, efficient method, specifically for a pilot scale ribbon blender, in which maximum homogeneity in fortified dairy-based powder blends could be reached. In phase one, a red iron oxide pigment powder was mixed throughout a white dairy powder and color homogeneity was measured by comparing L*a*b* color values from powder samples extracted from different areas of the ribbon blender. For phase two, sixteen similar fortified dairy blends were produced with varying ribbon blade shaft rpm, fill level, and blending durations according to a response surface method (RSM). The level of homogeneity of ferrous sulfate in the dairy blend was measured in these fortified mixtures to determine optimal blender parameters. After operating parameters were determined for uniform blending, phase three was enacted using these parameters. A comparison study of nutrient stability in fortified model non-agglomerated powder infant formula (PIF) and agglomerated whey protein concentrate (WPC) powder blends was executed to evaluate the degradative effect of microencapsulated ferrous sulfate (MFS) vs. unencapsulated ferrous sulfate (UFS) in these fortified dairy blends. The nutrient degradation rates of vitamins A, E and C in both PIF and WPC base powder, fortified with either MFS or UFS, were determined and compared during an accelerated eight-week stability study. Using p = 0.05, no statistically significant differences in vitamin degradation rates were observed when comparing independent spray-dried dairy-based blends containing unencapsulated or microencapsulated ferrous sulfate (using an encapsulating composition of 60% stearic acid) during eight weeks of accelerated shelf-life storage conditions (37 °C with a 75% relative humidity, RH). Of note, the degradation rates of vitamins A and E in blends containing PIF and UFS were more rapid than the control and suggestively significantly different (p = 0.07).
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10

Wilson, Louise R. "A systems biology approach to studying the effect of increasing vitamin D intake through food fortification on 25OHD status, in different population groups". Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/810863/.

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Vitamin D deficiency is a major public health concern in the UK. As the natural sources of vitamin D in the UK are limited, supplementation or food fortification are possible strategies for achieving the dietary recommendations of 10 μg/d that will be introduced in 2016 for the whole population. However, there is controversy as to whether vitamin D2 and vitamin D3 are equally effective at raising vitamin D status (25OHD concentration). The primary and secondary aims of this PhD project were: to investigate the effects of both these forms of vitamin D independently on vitamin D status, markers of bone and cardiovascular health, and gene expression; as well as to examine whether common genetic variants affect response to either form of vitamin D. A cohort of 90 South Asian and 245 Caucasian women were recruited onto a randomised-controlled trial; the D2-D3 Study. Participants were given either 15 µg/d of vitamin D2, 15 µg/d of vitamin D3 or placebo, in fortified foods, for 12 weeks. At baseline, serum total 25OHD concentrations were significantly lower in the South Asian women (27.6 nmol/L) than the Caucasian women (60.3 nmol/L). In both the South Asian and Caucasian women, 25OHD concentrations significantly decreased in the placebo intervention (-5% and -15% respectively, p<0.001), and significantly increased in both the vitamin D2 (112% and 39% respectively, p<0.001) and the vitamin D3 interventions (243% and 72% respectively, p<0.001), with significantly greater increases seen in the vitamin D3 intervention (p<0.001). In the vitamin D3 groups, parathyroid hormone (PTH) concentrations decreased in the South Asian women (p<0.001), who had higher baseline concentrations, and were maintained in the Caucasian women, who had healthy baseline PTH concentrations. This effect was not seen with vitamin D2 fortification. Over the 12 weeks, there were no clinically relevant changes in blood lipid concentrations in response to either vitamin D2 or D3, in the South Asian and Caucasian women. Interestingly, whole blood transcriptome analysis indicated that the vitamin D2 and D3 interventions triggered a difference in expression of entirely different genes, and predicted therefore a difference in the activity of the respective metabolic and cellular pathways. The associations between genetic polymorphisms and change in 25OHD concentration in response to vitamin D also appear to differ depending on the form of vitamin D taken, although baseline 25OHD concentration may be a confounder. The implications of this work, as the largest RCT conducted to date and showing conclusively that vitamin D3 is more effective than vitamin D2 at raising total 25OHD concentration and achieving or maintaining a healthy PTH concentration, are important: in the clinical setting vitamin D3 may be preferable in the treatment of vitamin D deficiency. The novel findings that vitamin D2 and vitamin D3 lead to different metabolic/cellular responses requires further research to determine whether the response to vitamin D2 is due to a decrease in 25OHD3 concentration (observed in this study following vitamin D2 treatment) or whether it is in response to the increase in 25OHD2 concentration.
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11

Jelena, Milešević. "Razvoj prediktivnog modela obogaćivanja prehrambenih proizvoda vitaminom D u Srbiji". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110223&source=NDLTD&language=en.

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Kreirana je specijalizovana baza podataka o sadržaju vitamina D koja sadrži 981 analitički podatak prikupljen iz evropskih baza podataka, od čega je 658 (67%) izraženo u formi ukupnog vitamina D. Podaci o svim vitamerima pronađeni su za meso, obogaćene namirnice/formulacije i za ribu, dok su podaci o D3 pronađeni za ribu, meso i mlečne proizvode. Podaci o sadržaju vitamina D, iz srpske baze podataka o sastavu namirnica (BPSN), ažurirani su za ukupno 541 namirnicu, jelo i dijetetski suplement.Da bi se upotpunio kvalitet podataka o vitaminu D u srpskoj BPSN, određen je sadržaj vitamina D u svežim konzumnim kokošijim jajima proizvedenim na teritoriji Srbije. Analizirana su jaja iz intenzivne proizvodnje i iz malih domaćinstava. Analize su izvedene u laboratoriji Danskog Tehničkog Univerziteta (DTU) standardizovanom HPLC metodom. Sadržaj vitamina D u jajima iz intenzivne proizvodnje iznosio je 5,78 μg/100g, a u jajima iz slobodnog uzgoja 2,99 μg/100 g. Izračunati prosečni sadržaj vitamina D u svežim jajima iznosio je 4,39 μg/100 g te je ovaj podatak unet u srpsku BPSN.Uobičajeni unos vitamina D analiziran je programom SPADE u populaciji koju su činili ispitanici iz četiri regiona Srbije, ukupno 605 odraslih, od toga 54% žena. Ustanovljeno je da uobičajeni prosečni unos vitamina D iznosi 4±1,4 μg/dan, kod muškaraca 4,3±1,5 μg/dan, a kod žena 3,7±1,2 μg/dan, što je znatno niže od preporučenih vrednosti od 10 μg/dan za procenjene prosečne potrebe (Estimated Average Requirement-EAR) i 15 μg/dan za adekvatni unos (Adequate Intake –AI). Čak 95% srpske populacije ne dostiže EAR vrednosti.Analiza ishrane srpske populacije pokazala je da su glavni nutritivni izvori vitamina D jaja, riba, meso i mlečni proizvodi. Konzumacija obogaćenih namirnica vitaminom D (obogaćenih i biljnih mleka, kakao praha, obogaćenih sokova, margarina i instant žitarica) identifikovana je kod trideset petoro ispitanika. Prateći kriterijume za odabir adekvatnih namirnica za obogaćivanje, a za potrebe dizajniranja prediktivnog modela, odabrano je 70 namirnica koje su sortirane u sedam karakterističnih grupa: beli hleb, mleko, jogurt, sir, pavlaka, jaja i paradajz pire.Prediktivni model obogaćivanja namirnica baziran je na matematičkoj formuli kojom se izračunava količina vitamina D (fc) koju treba dodati određenoj namirnici, odnosno grupi namirnica. Izračunata količina zavisi od tri faktora:- prosečne konzumacije date namirnice, ili grupe, u gramima na n-tom percentilu populacije,- njenog (njihovog) procentualnog udela u dnevnom energetskom unosu,- unosa vitamina D (u μg/dan) na n-tom percentilu.Odabrano je sedam scenarija koji su simulirani da bi se validirala efektivnost „dodavanja“ vitamina D radi dostizanja preporučenih nutritivnih vrednosti. U optimalnom scenariju, AI je dostignut na 65. percentilu populacije, a unos vitamina D na 95. percentilu populacije bio je ispod 25 μg/dan. U maksimalnom scenariju, 50% populacije bilo je između AI i gornjeg tolerisanog nivoa nutritivnog unosa (Upper Tolerable Intake Level-UL), pri čemu niko nije dostigao UL vrednosti. Na ovaj način definisane su optimalne i maksimalne količine vitamina D koje se mogu dodati odabranim namirnicama da bi se zadovoljile potrebe, odnosno korigovao unos vitamina D kod srpske populacije.
A specialized database on the content of vitamin D was created with 981 analytical data on vitamin D content obtained from European databases, of which 658 (67%) were expressed as total vitamin D. The data (for all vitamins) were mainly found for meat, enriched foods/formulations and fish, while D3 data was identified for fish, meat and dairy products. Updating data on vitamin D content in Serbian food composition database (FCDB) was done in 541 foods, dishes and dietary supplements. To enhance the quality of data in Serbian FCDB, content of vitamin D in fresh eggs from the farm and domestic production on the territory of Serbia has been determined. Analysis was performed in Danish Technical University-DTU, Denmark, using standardized HPLC method. Eggs from the farm contained 5.78 μg vitamin D/100 g, while domestic eggs were 2.99 μg vitamin D/100 g, and the average vitamin D content in fresh eggs - 4.39 μg/100 g which value was inserted into Serbian FCDB. The usual dietary intake of vitamin D was analyzed using the SPADE program in the survey covering 605 adult respondents from four regions of Serbia, of which 54% were women. The average intake of vitamin D was found to be 4±1.4μg/day, which is 4.3±1.5 μg/day for men and 3.7±1.2 μg/day for women, and is significantly lower than the recommended Estimated Average Requirement (EAR) values (10 μg/day) and Adequate Intake (AI) values (15 μg/day). As many as 95% of Serbian population are not reaching the EAR values. Nutritional analysis of Serbian diet has shown that the main sources of vitamin D are eggs, fish, meat and dairy products. Consumption of vitamin D-fortified foods (fortified and plant milk, cocoa powder, fortified juices, margarine, and instant cereals) was identified in 35 subjects. Following the criteria for selecting adequate foods for fortification, for the needs of designing the model, 70 foods were selected that were sorted into 7 characteristic food groups: white bread, milk, yoghurt, cheese, sour cream, eggs and tomato puree.The prediction model of food fortification is based on a mathematical formula that calculates the amount of vitamin D (fc) to be added to a particular food group in accordance with:- the amount of consumption of that food vector and- the percentage factor in the total energy intake of the considered foods (food vectors) in the observed population,- the intake of vitamin D on n-th percentile.Seven scenarios were simulated to validate the effect of addition of vitamin D toward reaching the given reference values. In the optimal scenario, AI was reached at the 65th percentile of the population, and vitamin D intake at 95th percentile was below 25 μg/day. In the maximum scenario, 50% of the population was between AI and Upper Tolerable Intake Level (UL), while none has reached UL values. This defines the ranges of optimal and maximum values of vitamin D that, by being added to the chosen food-vectors, can help in reaching vitamin D requirements of Serbian population.
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Hardy, Dallin Max. "Sensory Acceptability and Nutrient Stability in Micronutrient-Fortified Soymilk Prepared in Small-Scale Batch Processes". BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/8284.

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Fortified and unfortified soymilk were produced from the same production batches for comparative evaluation. Fortification included a comprehensive array of micronutrients of interest to community and humanitarian nutrition programs. The effects of time after fortification prior to cooling, cooling method, and light or dark refrigerated storage on the stability of 5 vitamins (vitamin A, vitamin C, thiamine, riboflavin, and folate) were investigated for both fortified and unfortified soymilk. Significant vitamin C loss (6%) and mild vitamin A isomerization occurred while soymilk was hot immediately following fortification. Cooling bottled soymilk in an ambient water bath or ice water bath made no difference in the levels of any of the vitamins measured. Significant loss of riboflavin (18%) and significant vitamin A isomerization to cis isomers other than 13-cis, resulting in loss of bioactivity, occurred during 12 days of light-exposed refrigerated storage. An increase of 13-cis isomer was observed in dark refrigerated storage but with no significant loss of vitamin A bioactivity. No significant degradation of any other vitamins occurred during 12 days of dark refrigerated storage. Sensory evaluation by a panel of youth and children revealed no significant preferences between fortified and unfortified soymilk excepting colour, for which property there was a slight preference for unfortified soymilk. Acceptable vitamin stability and sensory characteristics can be achieved in comprehensively fortified soymilk produced in small-scale batch processes with appropriate management of production and storage conditions.
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13

Silva, Lara Lívia Santos da. "Fortificação da alimentação complementar com múltiplos micronutrientes em pó na prevenção da anemia e no estado nutricional de vitamina A em crianças da Atenção Básica &ag". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-04012018-142026/.

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Abstract (sommario):
Introdução - A anemia e a deficiência de vitamina A (DVA) estão entre os principais problemas de saúde pública no mundo. No Brasil, 20,9 por cento das crianças menores de cinco anos apresentam anemia e 17,4 por cento DVA. Recentemente, a Organização Mundial de Saúde recomendou o uso de múltiplos micronutrientes em pó (MNP) para assegurar o aporte adequado de vitaminas e minerais da alimentação complementar. Embora essa estratégia seja considerada eficaz na prevenção da anemia ferropriva, é ainda controverso seu impacto no estado nutricional de vitamina A. Objetivo - Os objetivos desta tese foram: avaliar o impacto da fortificação da alimentação complementar com MNP no estado nutricional de vitamina A (artigo 1), investigar fatores associados à anemia (artigo 2) e descrever o estado nutricional de folato e vitamina B12 e o efeito dessas vitaminas no risco para anemia (artigo 3) em crianças atendidas em Unidades Básicas de Saúde (UBS). Métodos - Trata-se de um estudo de intervenção multicêntrico, do tipo ensaio pragmático, realizado em 24 UBS de quatro cidades brasileiras (Goiânia, Olinda, Porto Alegre e Rio Branco) - Estudo Nacional de Fortificação caseira da Alimentação Complementar (ENFAC). A coleta de dados ocorreu entre junho de 2012 e junho de 2013. No início do estudo, o grupo controle (GC) foi constituído por crianças de 10 a 14 meses de idade (n=521) atendidas na rotina vigente de puericultura e, paralelamente, o grupo intervenção (GI) foi constituído por crianças entre seis e oito meses de idade (n=462) que passaram a receber a intervenção com MNP uma vez ao dia por um período de dois a três meses. No artigo 1, modelos de regressão de Poisson multinível foram utilizados para analisar o impacto da fortificação no estado nutricional de vitamina A, comparando-se as crianças do GI, após quatro a seis meses de acompanhamento, com as crianças do GC. Nos artigos 2 e 3, modelos de regressão de Poisson multinível foram utilizados para investigar fatores associados ao risco para anemia (concentração de hemoglobina sanguínea <110 g/L) e o efeito combinado do estado nutricional de vitamina B12 e folato em relação ao risco de anemia. Resultados - No artigo 1, a prevalência da DVA (retinol sérico <0,7 ?mol/L) nas crianças do GC foi de 16,2 por cento enquanto no GI foi de 7,5 por cento , representando uma redução de 55 por cento na prevalência de DVA no GI quando comparado ao GC. Esta redução foi também significativa na vigência ou ausência do Programa Nacional de Suplementação de Vitamina A. A média ajustada das concentrações de vitamina A melhorou no GI, quando comparado ao GC, com um desvio à direita na distribuição da vitamina A. No artigo 2 foi observado que 23,1 por cento das crianças do GC apresentavam anemia, sendo a presença de mais de uma criança <5 anos na casa, introdução de frutas e legumes após oito meses de idade, desnutrição, hospitalização prévia e menores concentrações de folato associados ao maior risco para anemia. No artigo 3, observou-se elevada concentração mediana de folato sérico (39,7 nmol/L) e 15 por cento de deficiência de vitamina B12 (< 148 pmol/L). O efeito combinado de altas concentrações de folato com valores de vitamina B12 >= 148 pmol/L reduziu o risco para anemia enquanto que a condição de altas concentrações de folato com baixas concentrações de vitamina B12 não foi associada a maior risco para anemia nessa população. Conclusões - A fortificação da alimentação complementar com MNP reduziu a prevalência de DVA e melhorou o estado nutricional desta vitamina nas crianças participantes do ENFAC. Estratégias para apoio, promoção e proteção do aleitamento materno e da alimentação complementar saudável são essenciais para a prevenção da anemia e garantia de um estado nutricional adequado de micronutrientes na infância.
Introduction - Anemia and vitamin A deficiency (VAD) are among the major public health problems in the world. In Brazil, 20.9 per cent of children under five years of age have anemia and 17.4 per cent VAD. Recently, the World Health Organization recommended the use of multiple micronutrients in powder form (MNP) to promote adequate intake of vitamins and minerals in complementary feeding. Although this strategy is considered effective in the prevention of iron deficiency anemia, its impact on the nutritional status of vitamin A is still controversial. Objectives - The objectives of this thesis were: to evaluate the impact of fortification of complementary feeding with MNP on vitamin A status (article 1), to investigate factors associated with anemia (article 2) and to assess the nutritional status of folate and vitamin B12 and explore their combined effect on anaemia risk (article 3) in young Brazilian children attended at Primary Health Centers (PHC). Methods - This is a multicenter study, pragmatic intervention trial, carried out in 24 PHC in four Brazilian cities (Goiânia, Olinda, Porto Alegre and Rio Branco) - Estudo Nacional de Fortificação caseira da Alimentação Complementar (ENFAC). Data collection took place between June 2012 and June 2013. At study baseline, the control group (CG) consisted of children 10-14 months old (n = 521) attending in routine pediatric health care and, in parallel, the intervention group (IG) was composed of children between 6-8 months old (n = 462) who followed the MNP intervention once daily for a period of two to three months. In article 1, multilevel Poisson regression models were used to analyze the impact of fortification on vitamin A status, comparing the IG children, after four to six months follow-up, with the CG children. In articles 2 and 3, multilevel Poisson regression models were used to investigate risk factors for anemia (blood hemoglobin concentration <110 g/L) and the combined effect of folate and vitamin B12 status on anemia risk among CG children. Results - In article 1, the prevalence of VAD (serum retinol <0.7 ?mol/L) in the CG was 16.2 per cent , while in the IG was 7.5 per cent , representing a 55 per cent reduction in the prevalence of VAD in the IG when compared to the CG. This reduction was also significant when stratifying the study centers by coverage of the National Vitamin A Supplementation Program. The adjusted mean of vitamin A serum concentrations improved in the IG compared with CG children, with a shift to the right in the vitamin A distribution. In article 2, it was observed that 23.1 per cent of children in the CG had anemia, with more than one child <5 years old in the household, introduction of fruits and vegetables after eight months of age, stunting, previous hospitalization and lower concentrations of serum folate associated with increased risk for anemia. In article 3, a high median serum folate (39.7 nmol/L) and 15 per cent of vitamin B12 deficiency (<148 pmol/L) were observed in these children. The combined effect of high serum folate concentration (>= 50.1 nmol/L) and vitamin B12 >= 148 pmol/L significantly reduced the risk for anemia whereas the condition of high serum folate concentrations and low vitamin B12 concentrations was not associated with an increased risk for anemia in this population. Conclusion - The fortification of complementary feeding with MNP reduced the prevalence of VAD and improved the vitamin A status in children participating in the ENFAC. Strategies to support, promote and protect breastfeeding and healthy complementary feeding are essential for the prevention of anemia and ensuring an adequate nutritional status of micronutrients in childhood.
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14

Moreschi, Elaine Cristina Pinto. "Desenvolvimento e validação de métodos cromatográficos e avaliação da estabilidade de vitaminas hidrossolúveis em alimentos". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15032007-140659/.

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Abstract (sommario):
A adição de vitaminas aos produtos industrializados tornou-se prática comum para as indústrias de alimentos e os teores adicionados devem obedecer à legislação brasileira durante toda a vida de prateleira dos produtos. Sabendo da sensibilidade das vitaminas a fatores como oxigênio, luz e calor, é essencial conhecer o comportamento destes compostos no alimento frente aos fatores críticos. Informações confiáveis sobre teores de vitaminas somente podem ser obtidas com métodos analíticos validados. Neste trabalho foi desenvolvido e validado um método de análise para vitaminas B1, B2, B6 e PP em leite em pó/fórmulas infantis, cereais e bebidas instantâneas por cromatografia líquida de alta eficiência com uma única etapa de extração que apresentou recuperações de 90 a 120% dependendo do teor e da matriz analisada. Após a validação do método analítico, foi avaliada a estabilidade das vitaminas em amostras submetidas a diferentes condições de estocagem durante 10 meses. Os resultados mostram que a principal causa de perda das vitaminas B2 e B6 é a exposição à luz, que pode ser agravada pela temperatura e/ou presença de oxigênio no meio, enquanto as vitaminas PP e B1 mostraram-se bem estáveis sob as diferentes condições e no tempo estudado.
Food fortification with vitamins is a very common practice in food industry and the added content must be in compliance with Brazilian Legislation during the whole product shelf life. Due to the vitamins sensibility to light, temperature and oxygen it\'s necessary to know the behavior of these compounds when submitted to these critical conditions. Trustful information about the vitamins content just can be obtained from validated analytical methods. In this work it was developed and validated a HPLC method for determination of vitamins B1, B2, B6 e PP in milk/infant formula, cereals and beverage powders with the same extract which presented recoveries within 90 and 120% depending on the matrix and the vitamins level. After method validation, the vitamins stability in different samples was evaluated during 10 months under different storage conditions. The results showed the high sensitivity of vitamins B2 and B6 to light exposure that can become worse when samples were exposed to high temperature and oxygen. Vitamins PP and B1 had very stable behavior under the studied conditions and for the period of this study.
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15

Mousties, Célia. "Caractérisation des aliments fortifiés en circuits réels de distribution : impact de la température et de l'oxygène sur les cinétiques de dégradation". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG037.

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Abstract (sommario):
Dans le monde, la malnutrition touche encore 200 millions d’enfants en âge préscolaire. La nutrition infantile est alors un enjeu majeur dans les pays du Sud. Pour cela, la fortification alimentaire est largement utilisée pour combattre les problèmes de santé publique liés aux carences en micronutriments. Cependant, tout au long de la chaîne de logistique, le transport, le stockage sur de longues périodes et les conditions de distribution peuvent affecter le profil nutritionnel de ces aliments fortifiés. L’objectif de ces travaux de thèse était d’évaluer la qualité nutritionnelle d’aliments fortifiés afin d’identifier les déterminants (facteurs intrinsèques, facteurs environnementaux, emballage…) de la stabilité et de simuler le comportement de ces aliments dans le système de distribution via une approche cinétique.Pour cela, un panel de produits fortifiés comprenant des farines infantiles fortifiées (FI) et des aliments thérapeutiques prêts à l’emploi (ATPE) ont été collectés sur le terrain et étudiés, avec un focus sur le profil lipidique, les vitamines liposolubles (A, D et E), le statut oxydatif (indices de peroxyde et d’acide, composés secondaires d’oxydation) et les mycotoxines. Les résultats ont montré une qualité et une stabilité nutritionnelle moindre pour les FI que les ATPE. Une matrice modèle de type FI a, ensuite, été développée. Deux études cinétiques ont alors été menées pour évaluer la stabilité du complexe minéral et vitaminiques (CMV) et de la farine infantile modèle fortifiée ; pour cela, différentes températures et teneurs en oxygène du milieu environnant ont été testées. Les vitesses de dégradations et énergies d’activation des réactions de dégradations des vitamines ont été calculées. Intégrées dans un modèle mathématique prédictif, elles permettent d’estimer la rétention des vitamines dans les FI en fonction des températures des circuits de distribution et à terme en fonction des propriétés barrière aux gaz des matériaux d’emballage. Ce travail a pu souligné les problèmes de qualité et stabilité nutritionnelle des matrices fortifiées. Il est vraiment nécessaire de porter une attention particulière aux modalités de commercialisation des produits pour garantir les allégations nutritionnelles et pour favoriser une réelle efficacité biologique
In the world, malnutrition still affects 200 millions of preschool-age children. Infant nutrition is a major challenge in low income countries. Then, food fortification is widely used to address the public health problem of micronutrient deficiencies. However, along the supply chain, shipping, long term storage, and retailing conditions can affect the nutritional profile of fortified food. The objective of this thesis was to assess the nutritional quality of fortified food to identify the determinant (intrinsic factors, environmental factors, packaging) of the stability and to simulate the behaviour in the distribution system via a kinetic approach.A panel of fortified food including fortified infant flour (FI) and ready to use therapeutic food (RUTF) has been collected in the field and studied, with a focus on lipid profile, lipophilic vitamins (A, D and E), oxidative status (peroxide and acid index, secondary oxidation compounds) and mycotoxins. The results have shown a less quality and nutritional quality for the FI than the RUTF. Two studies were conducted, on the complex mineral and vitamins (CMV) and on the fortified infant flour model fortified with the CMV; distinct temperatures and oxygen contents of the environment were tested. The initial rate and activation energy of the degradation reactions of vitamins were calculated. In a mathematic model, they allow us to estimate the vitamin retention in FI according to the temperatures of the supply chains and, in a next step, according to the barrier properties to gas transfer of packaging materials. Our research has underlined the issues of quality and stability of fortified food. It is really necessary to pay attention to the parameters of distribution and commercialization of these products to guarantee the nutritional claims and favor a real biological efficiency
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16

Hassel, Sarrah. "Application of a Handheld Infrared Sensor for Monitoring the Distribution of Vitamins and Minerals in Fortified Corn-based Snacks". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250602087.

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17

Al-Khalidi, Banaz. "Casein Proteins as a Vehicle to Deliver Vitamin D3: Fortification of Dairy Products with Vitamin D3 and Bioavailability of Vitamin D3 from Fortified Mozzarella Cheese Baked with Pizza". Thesis, 2012. http://hdl.handle.net/1807/33319.

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Abstract (sommario):
Current vitamin D intakes in Canada are inadequate. The extension of vitamin D fortification to additional foods may be an effective and appropriate strategy for increasing vitamin D intakes in the general population. Cheese is potentially an ideal candidate for vitamin D fortification. We introduce the potential use of casein proteins as a vehicle for vitamin D3 fortification in industrially made cheeses where we found that over 90% of vitamin D3 added to milk was retained in both Cheddar and Mozzarella cheeses. Use of casein proteins for vitamin D3 fortification did not fully prevent vitamin D3 loss into whey. However the loss was minimized to approximately 8%. We then show that vitamin D3 is bioavailable from fortified Mozzarella cheese baked with pizza suggesting that the high temperature baking process does not significantly breakdown vitamin D3. Our findings could have important implications in increasing fortified food options for Canadians.
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18

Wagner, Dennis. "Fortification of hard cheese with vitamin D(3): Stability and bioavailability of vitamin D(3) from fortified cheeses". 2008. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=772047&T=F.

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19

Kwan, Lana. "Triple Fortification of Salt with Vitamin A, Self-emulsifying Drug Delivery System, Iron, and Iodine". Thesis, 2012. http://hdl.handle.net/1807/32478.

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Abstract (sommario):
Triple fortification of salt with vitamin A, iron, and iodine has been investigated in the past to reduce micronutrient deficiencies in the developing world. The objective is to develop integrated nutrient delivery technology by microencapsulating a self-emulsifying drug delivery system (SEDDS) made of surfactants and a bioactive compound, retinyl palmitate. The SEDDS is used to enhance absorption of the vitamin A through food systems and to achieve targeted release of the active ingredient. Encapsulating vitamin A was difficult when using the spray dryer and the enteric coating, Aquacoat®. Losses of the micronutrient after a three month storage period ranged from 50-99% at both 25°C/20% RH and 45°C/60% RH. The result of a matrix encapsulation and poor coating formation contributed to the high losses. Further investigation of coating systems with the aim of stabilizing all three samples for a six month storage period such as using other encapsulating methods is recommended.
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20

Masih, Shannon. "Maternal Intakes and Sources of Folate and other One-carbon Nutrients in the Post-fortification Era". Thesis, 2013. http://hdl.handle.net/1807/43178.

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Abstract (sommario):
This study characterizes B vitamin supplement use prior to and during pregnancy, changes in dietary one-carbon nutrient intakes (folate, vitamin B12, vitamin B6, choline, betaine and methionine) and most significant dietary sources. In Canadian women (Toronto, Ontario) supplemental (n=364) and dietary intakes (using a food frequency questionnaire) (n=290) were assessed during early and late pregnancy. Majority reported using a B vitamin-containing supplement prior (60%) to and during early (93%) and late (89%) pregnancy. Median supplemental intakes of folic acid, B12 and B6 were 1000 µg/d, 2.6 µg/d and 1.9 mg/d, respectively. Dietary one-carbon nutrient intakes did not change appreciably between early and late pregnancy. Most significant sources of folate and B6 were fruits and vegetables, of folic acid were cereals and grains and of B12 were dairy and egg products. Overall, this study provides novel information about one-carbon nutrient intakes in pregnancy which are crucial in maternal and child health.
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21

Paterson, Linda Jane. "Prevalence of Hyperhomocysteinemia in Patients with Chronic Kidney Disease After Folic Acid Food Fortification of the Canadian Food Supply". Thesis, 2011. http://hdl.handle.net/1807/27358.

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Abstract (sommario):
Elevated plasma total homocysteine (ptHcy) or hyperhomocysteinemia (hHcy) independently predicts cardiovascular disease in predialysis chronic kidney disease (pCKD). Folate status is one of the known nutritional determinants of ptHcy. In the era of folic acid food fortification, this cross-sectional study aimed to describe in pCKD subjects (n=48): 1) Prevalence of hHcy. 2) Intake and status of nutrients involved in homocysteine metabolism. 3) Determinants of ptHcy. The prevalence of hHcy was 93.8% (95% CI: 81.8 to 98.4). Median (25th, 75th percentile) total folate intake from food and supplements was 389 (282,640) µg DFE/d. No subject was folate deficient (red blood cell < 317 nmol/L). Red blood cell folate (r = - 0.406, p=0.004) and energy-protein undernutrition (r = 0.357, p=0.013) independently predicted ptHcy. To conclude, total folate intake among subjects with pCKD was sufficient to prevent folate deficiency but not able to prevent a high prevalence of hHcy.
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22

Steele, Benjamin D. "The Masking Effect: A comparison of pre and post folic acid fortification periods for vitamin B-12 deficiency without macrocytosis in the United States". 2014. http://scholarworks.gsu.edu/nutrition_theses/56.

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Abstract (sommario):
Background: There has been a concern regarding the masking of vitamin B-12 deficiency in the post-fortification period (after January 1, 1998). Objective: The objective of this study was to investigate the potential masking of vitamin B-12 deficiency by comparing the proportion of individuals with low serum B-12 without macrocytosis between pre- and post-fortification periods using data from the National Health and Nutrition Examination Survey (NHANES). Methods: The study included 7242 individuals from NHANES III (pre-fortification group) and combined NHANES 1999-2000, 2001-2002, 2003-2004, 2005-2006 (post-fortification group). Vitamin B-12 deficiency and macrocytosis were defined as having <148 pmol/L of serum vitamin B-12 and mean corpuscular volume (MCV) of>98 fL, respectively. A multivariate logistic regression was performed to estimate the likelihood of being low serum B-12 without macrocytosis in the post-fortification period in relation to the pre-fortification period. Results: Between pre- and post-fortification periods, there was no significant difference in the proportion of individuals with low serum vitamin B-12 without macrocytosis. However, odds of having low serum vitamin B-12 without macrocytosis in the post fortification era increased in men (OR=2.65, 1.24-5.65), non-Hispanic blacks (OR=3.12, 1.04-9.35), Non-smokers (OR=4.63, 1.90-11.27), and those aged 55 and older (OR=2.183, 1.01-4.74) compared their respective counterparts in the pre-fortification period. Conclusions: No significant difference in the proportion of individuals with vitamin B-12 deficiency without macrocytosiss was seen between the pre and post-fortification periods suggesting no making of vitamin B-12 deficiency. In the post-fortification period, serum folate was found to be a predictor of the masking effect. The impact of increased folic acid intake in the post-fortification period needs to be evaluated on a periodic basis especially, in non-target population.
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23

Pretorius, Beulah. "Vitamin A content and bio-availability of South African maize meal (as purchased and consumed)". Thesis, 2011. http://hdl.handle.net/2263/28134.

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Abstract (sommario):
In 2003 the Department of Health of South Africa embarked on a mandatory fortification programme of maize meal as part of the Integrated Nutrition Program (INP) to alleviate malnutrition. The aim of this study was two-fold: firstly, to determine the vitamin A content of South African fortified white maize meal as purchased and the maize porridge as traditionally prepared from it as consumed and secondly, to determine the relative efficacy of the daily consumption of maize meal in sustaining or improving vitamin A status. Maize meal samples for analysis were purchased from various supermarkets and small retail outlets. A High Performance Liquid Chromatograph-Diode Array Detector system with a Reverse Phase C-18 column and isocratic elution was used for separation and quantification of vitamin A. The highest mean vitamin A concentration measured in the maize meal was 261 μgRE/100g and the lowest mean vitamin A concentration was <19 μgRE/100g. Pertaining to the regulations the final minimum level of vitamin A in fortified maize meal must not be less than 187.7 μgRE/100g. The average retention of vitamin A in maize porridge as the difference in vitamin A concentration measured between raw maize meal and cooked porridge was calculated at 39.8%. One of the considerations in a fortification program is the availability of certain micronutrients in the fortified foods, with the focus in this project on vitamin A. An animal model, namely chickens, closely relating the metabolism of vitamin A in humans was used. Chickens are very susceptible to vitamin A deficiencies with similar symptoms. Growth and vitamin A status was evaluated by the weight, feed conversion and liver retinol stores of chickens on five different maize based diets over a six week period. No significant difference in vitamin A levels in the livers of birds on diets with fortified white maize meal, compared to the normal poultry diet consisting of yellow maize meal with added vitamin A was found. It can thus be concluded that the fortificant in the white maize meal is as bioavailable as the vitamin A in the premix used in poultry nutrition. The results of this study show that the vitamin A added as fortificant is absorbed and available to the body. Therefore, fortification of commonly eaten staple foods in the country can significantly improve the vitamin A intake of the population and will improve the overall micronutrient density of their diets. Fortification should be set at levels to include losses incurred through packaging and during transportation, shelf losses and preparation losses. It is also important that the vitamin A content of the product as purchased and consumed must be regularly monitored and regulated by government. Valid and reliable evaluation data are needed to evaluate a program’s success, and to make timeous adjustments for optimal efficiency.
Thesis (PhD)--University of Pretoria, 2011.
Animal and Wildlife Sciences
unrestricted
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24

Ramashia, Shonisani Eugenia. "Physical, functional and nutritional properties of flours from finger millet (Eleusine coracana) varieties fortified with vitamin B₂ and zinc oxide". Thesis, 2018. http://hdl.handle.net/11602/1245.

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Abstract (sommario):
PhD (Food Science and Technology)
Department of Food Science and Technology
Finger millet (FM) (Eleusine coracana) grains are the staple food in Africa and India for communities with low socio-economic growth. The grains have high content of calcium, dietary fibre, carbohydrates that are rich in protein, fat, iron, phosphorus, vitamin and essential amino acids. Flours from milky cream (MC), brown and black varieties of FM were fortified with vitamin (vit) B₂ and zinc oxide (ZnO) in order to restore the nutrients that were lost during milling and sieving processes. The main aim of the study was to analyse the physical, nutritional composition and functional properties of flours from three (3) FM varieties fortified with vit B2 and ZnO. Pearl millet was used for comparison with the results obtained from this study. MC, brown and black varieties of FM flour treatments were arranged as a completely randomized design (CRD) in three (3) replicates. Physical properties: dimensional properties, colour attributes, kernel weight, bulk density (BD), true density, porosity, surface area, kernel volume, aspect ratio, sphericity and moisture content of the FM grains were analysed. Vitamins and minerals were also analysed. Functional properties: colour attributes, bulk density (BD), water absorption capacity (WAC), oil absorption capacity (OAC), swelling capacity (SC), swelling index (SI), foaming capacity (FC), foaming solubility (FS), dispersibility (Dis), viscosity (cool & hot paste), pasting properties, thermal properties and microscopic structure of FM flours were determined. Data generated were analysed using SPSS version 23.0. Moisture content of MC FM grain and flour was significantly higher (p < 0.05) than brown and black varieties but was within the specified range of <12%. This indicated the long storage shelf-life of the grains and flours. Length of brown FM grains was significantly higher (p < 0.05) when compared to MC and black varieties. MC variety was significantly higher than other varieties in width, kernel weight, bulk density, true density, aspect ratio and sphericity. The information obtained from this study will help in designing suitable equipment for planting, harvesting, storage, processing and packaging of grains. Pearl millet grain was significantly higher than FM flours in all physical properties. MC FM was significantly higher iii in L* (whiteness/ brightness), b* (yellowness/ blueness), C* (chroma), Hº (hue angle) and ZnO values compared to brown and black flours. MC raw fortified finger millet (RFFM) and instant fortified finger millet (IFFM) flours were significantly higher in vitamin B2. People prefer fortified MC flour because most of people living in South Africa use white maize as their staple food and it is similar to MC. Colour is the most important quality parameter in food processing industries and it is also attracts the consumer’s choice and preference. The vitamins and minerals that were lost during sieving, drying and milling were replaced by the two (2) fortificants added which may help to reduce the micronutrient deficiencies. Milky cream FM flours showed significantly high (p < 0.05) values in BD, WAC, OAC, SI, FC and dis. These are the fundamental physico-chemical properties that reflect the interaction between the composition and molecular structure. Length of brown FM grains was significantly higher (p < 0.05) when compared to MC and black variety. The MC variety was significantly higher than other varieties in width, kernel weight, bulk density, true density, aspect ratio and sphericity. Pearl millet was significantly higher than FM flours in all physical properties. MCFM variety was significantly higher in L* (whiteness/ brightness), b* (yellowness/ blueness), C* (chroma), and Hº (hue angle) values as compared to other FM varieties. Moisture content of MC flour was significantly higher as compared to brown and black FM flours. Pasting properties of MC raw finger millet (RFM) and RFFM flours showed significantly higher in peak viscosity (PV) (3518 cP), final viscosity (FV) (6554 cP), breakdown viscosity (BDV) (703 cP) and setback viscosity (SV) (3868 cP) as compared to other RFM and RFFM flours. Brown instant finger millet (IFM) and IFFM flours had significantly higher of PV (723 cP), trough viscosity (TV) (655 cP) and FV (983 cP). IFFM flours had significantly higher values of PV (712 cP), TV (614 cP) and FV (970 cP), respectively. The instant pearl millet (IPM) and instant fortified pearl millet (IFPM) showed significantly higher value in BDV (330 cP and 131 cP) and SV (362 cP and 346 cP), respectively. Thermal properties of black RFM was significantly higher in onset temperature (To) (74.31), peak temperature (TP) (81.94ºC) and conclusion temperature (Tc) (89.64) and RFFM starches were significantly high in To (81.80ºC), TP (84.22ºC) and TC (92.81ºC), respectively. Milky ivcream IFM starch showed significantly higher values in TO (84.57ºC), TP (87.27ºC), Tc (92.81ºC) and ΔH (7.63ºC) compared to other starches. Brown IFFM flour was significantly higher value in To (85.88ºC) and TP (87.14ºC). The starch of IFPM was significantly higher in enthalpy of gelatinisation (6.91ºC) and PHI (2.94ºC) as compared to other FM starches. Brown IFM flour showed significantly higher value in gelatinisation temperature range (13.50ºC). The microscopic structure revealed that RFM and RFFM flours had oval and smooth surfaces. RFM and RFFM flours showed positive effect after fortificants were added because the starch granules, protein bodies and protein matrix were visible and formed crystal. IFM and IFFM flours had some holes, dents and rough surfaces. Instant fortified flours showed negative effect after fortificants were added due to technological processes such as recooking and remilling of flours. Different variations observed on physical, nutritional and functional properties after adding the fortificants may affect the physical, chemical and organoleptic properties of food produced from fortified flour. There is need to fortify FM flours with ZnO which may help to replace the value lost during milling and sieving operations. It is possible that the availability of ZnO could reduce the incidence of some non-communicable diseases.
NRF
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25

Chen, Po-Chang, e 陳柏璋. "Effect of Different Iron Compound and Vitamin Fortification on Iron Bioavailability in Reconstituted Milk with Different Fat Contents during in vitro digestion". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/93440921150259447455.

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Abstract (sommario):
碩士
東海大學
畜產與生物科技學系
96
By adding different kinds of iron compounds and vitamins in reconstituted milk with different fat contents, this study was to investigate how much the iron compound and vitamin fortification affect the bioavailability of iron in reconstituted milk. Vitamin A, D, E and folic acid were added in whole (3.5% fat content; RWM), low-fat (1.5% fat content; RLM) and skim (0.3% fat content; RSM) reconstituted milk fortified with ferrous sulfate (FeSO4), ferric chloride (FeCl3) and of 1/2 of each (Mix), respectively. Through the in vitro digestibility test, iron bioavailability can be indicated as dialyzable ferrous iron (DFe(II)), total dialyzable iron (TDFe) and nondialyzable ferrous iron (NDFe(II)). The results of split-plot statistic design showed the bioavailability of ferrous sulfate (FeSO4) was the highest among different irons, and then the mix iron (Mix); the ferric chloride (FeCl3) had the lowest bioavailability. For different fat contents, the results denoted that the fat contents reached 3.5% content, it can significantly promote the iron bioavailability. As for results of vitamins, it can be concluded that vitamin D and E can significantly improve the iron bioavailability and they are the most proper additive for iron-fortified content in whole reconstituted milk.
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26

Shakur, Abdul Yaseer. "The Impact of Folic Acid Fortification on the Folate Intake of Canadians, Factors Associated with Sub-optimal Blood Folate Status among Women, and the Effect of Vitamin/Mineral Supplemental Use". Thesis, 2011. http://hdl.handle.net/1807/32084.

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Abstract (sommario):
Food fortification and nutrient supplementation are important strategies to address micronutrient deficiencies. Mandatory folic acid fortification was implemented in Canada and the U.S. in 1998 to reduce the incidence of neural tube defects (NTD). However, the actual amount of folic acid added to foods has not been reported in Canada. We analyzed 95 fortified foods and found that there is 50% more folate in foods than that reported in food composition tables, which are primarily based on minimum mandated fortification levels. We then determined if these observed folate overages impacted the prevalence of dietary folate inadequacy or intakes above the Tolerable Upper Intake Level (UL). Using data from the 2004 nationally-representative Canadian Community Health Survey (CCHS) 2.2 (n = 35,107), adjusted for folate overages, we found a low prevalence of folate inadequacy in Canada post-fortification. However, few women 14-50y consumed 400µg/d of synthetic folic acid, an amount associated with maximal protection against an NTD. Conversely, we also showed that use of folic acid-containing supplements led to intakes >UL in the general population. To develop a tool that would help clinicians identify women with red blood cell (RBC) folate concentrations that were not maximally protective against an NTD (<906nmol/L), we used data from the nationally-representative U.S. National Health and Nutrition Examination Survey 2003-2006 to define risk factors of RBC folate <906nmol/L. We found that 35% of American women 19-45y had RBC folate <906nmol/L. Younger age, low dietary folate intake, not consuming supplemental folic acid, smoking, and being African-American were associated with increased risk of RBC folate <906nmol/L. Given our observations of a low prevalence of folate inadequacy and folic acid supplement use leading to intakes >UL, we used CCHS 2.2 data to compare the diets of supplement users and non-users in terms of inadequacy and intakes >UL for other nutrients. We showed that the prevalence of inadequacy was low for most nutrients, and from diet alone, supplement users were not at increased risk of inadequacy compared to non-users. Furthermore, inclusion of supplements led to intakes >UL above 10% for vitamins A, C, niacin, folic acid, and iron, zinc and magnesium.
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27

Sacco, Jocelyn. "An Examination of the Population Health Implications of Voluntary Food Fortification and Nutrition-related Marketing Practices in Canada". Thesis, 2012. http://hdl.handle.net/1807/34872.

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Abstract (sommario):
The 2004 Canadian Community Health Survey (CCHS) revealed many indicators of poor diet quality in Canada which, together with the high rates of obesity and diet-related chronic disease, suggest that shifts in dietary patterns are urgently needed. Given the widespread promotion of foods on the basis of nutrition and health, the aim of this work was to explore the population health implications of voluntary food fortification and nutrition-related marketing in Canada. Using the CCHS, the potential impact of a proposed discretionary food fortification policy on nutrient inadequacies and excesses was examined, in addition to the relationship between consumption of foods eligible to be fortified under this policy and indicators of dietary quality. To better understand the potential risk associated with liberal fortification practices, the National Health and Nutrition Examination Survey (2007-08) was used to examine potential for risk of excess associated with voluntarily fortified food consumption in the US, where these practices have long been permitted. The results suggest that proposed changes to voluntary fortification may reduce inadequacy and increase excess, and may reinforce poor diet patterns. Excessive nutrient intakes were also found to be associated with consumption of voluntarily fortified foods in the US, particularly among children. Therefore, there appears to be real potential for risk associated with voluntary fortification practices in Canada. The extent, nature, and population health implications of nutrition marketing in Canada was examined, using a survey of front-of-package nutrition-related marketing on foods within three large grocery stores in Toronto. Nutrition-related marketing was found on 41% of all foods surveyed, and was widely found on highly processed, often fortified foods. References to nutrients of public health concern (e.g. sodium, vitamin D) were infrequently found. Overall, this practice provides limited nutritional guidance. Current directions in nutrition policy in Canada should be re-evaluated, to ensure that they support healthy diet patterns.
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