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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Efeito de alguns parâmetros operacionais nas características físicas, físico-químicas e funcionais de extrusados da farinha de batata-doce (Ipomoea batatas) / Effect of some extrusion parameters on physical, physicochemical and functional properties of sweet potato flour extruded products

Borba, Alexandra Moreli 30 August 2005 (has links)
A batata-doce é uma hortaliça de grande potencial energético, com elevado teor amiláceo e pode ser utilizada para consumo direto e para industrialização. Uma das tecnologias industriais viáveis para o processamento de alimentos amiláceos como a batata-doce, é a extrusão. Por este processo pode-se produzir snacks ou farinhas instantâneas (pré-gelatinizadas). O objetivo do presente trabalho foi avaliar o efeito dos parâmetros operacionais umidade da mistura, temperatura de processo e rotação do parafuso do extrusor sobre as características dos extrusados de batata-doce. As características avaliadas nos extrusados foram o índice de expansão (IE) e a dureza (DUR). As farinhas dos extrusados foram avaliadas quanto aos parâmetros: cor (L*, a*, b* e diferença de cor, índice de absorção de água (IAA), índice de solubilidade em água (ISA), grau de gelatinização (GG) e pontos críticos de viscosidade (Rapid Visco Analyser), ou seja, viscosidade inicial (VI), pico de viscosidade (PV) após o aquecimento e antes do resfriamento, quebra de viscosidade (QV), tendência a retrogradação (TR) e viscosidade final (VF). Foi empregada a metodologia de superfície resposta, com delineamento fatorial incompleto 33, de 3 níveis e 3 variáveis independentes: umidade (15, 18 e 21%), temperatura na 3a zona (100, 120 e 140oC) e rotação da rosca (180, 210 e 240 rpm). O modelo de regressão adotado mostrou que a umidade e a temperatura afetaram significativamente o IE dos extrusados. Mantendo-se a rotação média constante, o IE aumentou com a elevação da temperatura do processo para misturas com baixos teores de umidade. Os menores valores de IE ocorreram para baixas umidades e temperaturas e também para elevadas umidades e temperaturas. O modelo de regressão adotado para DUR dos extrusados não foi significativo para os parâmetros estudados. Ao se avaliar as características tecnológicas das farinhas extrusadas, o IAA, o ISA e a TR não apresentaram modelo de regressão de significância estatística dentro dos níveis das variáveis independentes. As farinhas extrusadas apresentaram GG variando entre 82,0 e 99,7%, contudo o modelo de regressão também não foi significativo para esta variável. Quanto a cor das farinhas extrusadas, o parâmetro L* (luminosidade) aumentou e o valor a* tendeu ao negativo (verde) com o aumento da umidade do material até aproximadamente 20-21%. O componente b* tendeu ao positivo (amarelo) e a diferença de cor (DCO) das farinhas extrusadas aumentou com a redução da umidade da massa, independentemente da variação de temperatura de extrusão. Quanto aos parâmetros de viscosidade das farinhas extrusadas, a VI, o PV e a QV diminuíram com a elevação da umidade até 20-21% e posteriormente, com elevação dos teores de umidade, mostraram aumento. Já a VF das farinhas extrusadas foi inversamente proporcional à rotação da rosca. O estudo mostrou que é viável a produção de extrusados de farinha de batata-doce com boas características utilizando-se os níveis das variáveis operacionais do processo. / The sweet potato is a vegetable of great energetic potential with high starch content. It can to be processed through extrusion which is efficient on the processing of starchy foods. In this work the effects of extrusion parameters on sweet potato extrudates and flours characteristics were studied. The properties evaluated in extrudates were expansion index (EI) and texture (hardness). The physical, physico-chemical and functional properties assayed in the extrudated flours were: water absorption index (WAI), water solubility index (WSI), color (L*, a*, b*) and color difference (CD), degree of gelatinization (DG) and pasting properties as initial viscosity (IV), raw peak (RP), breakdown (BD), setback (SB), cold viscosity (CV) and final viscosity (FV). The study was carried out by using Response Surface Methodology through an incomplete factorial design 33 with 3 levels and 3 independent variables: moisture content (15, 18, 21%), extrusion temperature (100, 120, 140oC) and screw speeds (180, 210, 240 rpm). The moisture content and extrusion temperature significantly affected expansion index of the extrudates.There was no influence of the parameters studied over extrudates hardness. The extrudates EI increased with the high extrusion temperature and low moisture content when the screw speed was medium. It decreased with the low moisture and temperature and at higher moisture content and temperature. The changes in independent variables did not result in significant regression model to extrudates hardness. The technological characteristics of extruded flours, WAI, WSI, SB and DG, did not present significant regression model to the parameters studied. The flours presented DG varying from 82.0 to 99.7%. The L* (lightness) component increased and value a* decreased with the increase of the moisture content until 20-21%. The color difference (CD) and parameter b* increased as the moisture content decreased, independent of the extrusion temperature. The IV, RP and BD values decreased with the increase the moisture until 20-21%. The flour FV decreased as srew speed increased. The study showed that is viable the production of sweet potato extrudates with good characteristics using the independent variables of the process.
412

Impacto de ingrediente funcional sobre a saúde intestinal / Impact of functional ingredient on intestinal health

Souza, Gabriela Santos 20 May 2014 (has links)
O microbioma intestinal influencia de maneira positiva e/ou negativa o bem estar e o equilíbrio da saúde no organismo humano. Carboidratos não disponíveis, tais como frutanos e amido resistente (encontrado na farinha de banana verde), são ingredientes funcionais que resistem à digestão, estimulam o peristaltismo e o trânsito intestinal, e podem aumentar população de bactérias benéficas. O presente estudo teve como objetivo avaliar o impacto do consumo regular e descontinuado (durante 6 semanas e 3 vezes por semana) de sopas adicionadas de inulina (8 g) ou farinha de banana verde (FBV) (8 g), sobre o funcionamento intestinal em voluntários saudáveis. Para a avaliação do funcionamento intestinal, o questionário semanal Gastrointestinal Symptom Rating Scale foi validado para o idioma português (Brasil), apresentando alfa de Cronbach de 0,82 e correlação intraclasse de 0,83. Além desta ferramenta, também foi utilizado um questionário diário de hábito gastrintestinal, que inclui a Escala de Bristol. Após o consumo das sopas adicionadas de inulina, os voluntários apresentaram redução na consistência das fezes, aumento na frequência de evacuações e na necessidade de evacuar, entretanto foi observado aumento leve de flatulência. O grupo que consumiu sopas adicionadas com FBV apresentou redução na consistência das fezes, no tempo de trânsito intestinal, nas dores abdominais e na sensação de esvaziamento incompleto do intestino, e aumento na frequência diária de evacuações. Dessa forma, estes carboidratos não disponíveis, na frequência e período de consumo estudados, podem melhorar o funcionamento intestinal, sem causar efeitos de desconforto gastrintestinal / The intestinal microbiome can positively and / or negatively influence both well-being and health balance in the human body. Unavailable carbohydrates, such as fructans and resistant starch (present in unripe banana flour) are functional ingredients that resist digestion, stimulate peristalsis and intestinal transit, and may increase the population of beneficial bacteria. The present study aimed to assess the impact of regular and discontinued consumption (for 6 weeks and 3 times per week) of soups added inulin (8 g) or unripe banana flour (UBF) (8 g), on intestinal function of healthy volunteers. For the evaluation of intestinal function, the weekly questionnaire Gastrointestinal Symptom Rating Scale was validated to Portuguese (Brazil), with Cronbach\'s alpha 0.82 and intraclass correlation 0.83. Besides this tool, a daily questionnaire of gastrointestinal habits was also used, which included the Bristol Stool Form Scale. After consumption of soups added inulin, the volunteers presented a reduction on stool consistency, increased frequency of bowel movements and evacuating need, however slightly increased flatulence was observed. The group that consumed soup added UBF presented a decrease in stool consistency, intestinal transit time, abdominal pain and sensation of incomplete bowel emptying, and an increase in the frequency of bowel movements. Therefore, these unavailable carbohydrates, when consumed in the frequency and period of the present study, can improve bowel function without causing any gastrointestinal discomfort
413

Efeito da farinha de banana verde sobre o funcionamento intestinal de pacientes diabéticos, constipados, com doença renal crônica, submetidos a tratamento de hemodiálise / Unripe banana flour effect on bowel function of diabetic, constipated with chronic kidney disease patients undergoing hemodialysis treatment

Gumbrevicius, Iara 22 November 2016 (has links)
A farinha de banana verde (FBV), fonte de amido resistente, pode melhorar o funcionamento intestinal de indivíduos saudáveis, porém, esta propriedade ainda não foi estudada em voluntários com enfermidades que causam constipação intestinal. O objetivo deste estudo foi avaliar o efeito do consumo regular e não diário da farinha de banana verde sobre o funcionamento intestinal de pacientes diabéticos, com constipação intestinal, doença renal crônica, tratados com hemodiálise. Em ensaio clínico prospectivo, modelo cross-over, 21 pacientes do Centro de Nefrologia de Amparo-SP foram divididos em dois grupos, que consumiram 11,3 g de FBV ou 4 g de maltodextrina, três vezes por semana, por seis semanas, com período de washout de 30 dias. O funcionamento intestinal foi avaliado pelo Gastrointestinal Symptom Rating Scale e questionário de funcionamento intestinal diário com Escala de Bristol. Também foram avaliadas a qualidade de vida pelo Medical Outcomes Study Questionnaire 36 - Item Short Form Health Survey e as concentrações plasmáticas de jejum de glicose, insulina, colesterol total e frações, triacilgliceróis, potássio e fósforo dos pacientes. Com o consumo da FBV houve redução significativa de distensão abdominal (p=0,019), flatulência (p=0,021), fezes duras (p=0,008) e sensação de esvaziamento incompleto do intestino (p=0,000). Na primeira semana de consumo da FBV, o número de evacuações aumentou (p=0,003) e a consistência das fezes melhorou (p=0,001). Não foram observadas diferenças na qualidade de vida. As concentrações plasmáticas de jejum de glicose (p=0,012) e potássio (p=0,020) foram significativamente reduzidas. Como a constipação intestinal é uma das queixas predominantes de pacientes diabéticos tratados com hemodiálise, a farinha de banana verde pode contribuir de forma eficaz com o tratamento desse sintoma e adicionalmente, melhorar parâmetros bioquímicos importantes no tratamento desses pacientes. / Unripe banana flour (UBF), a resistant starch source, is able to improve bowel function in healthy subjects; however, this property has not been studied in subjects with diseases that may cause constipation. The aim of this study was to evaluate the effect of regular, non-daily consumption of UBF on bowel function of diabetic patients with constipation, chronic renal disease and treated with hemodialysis.In a prospective clinical trial, cross-over designed, 21 patients who were treated in the Nephrology Center of Amparo city (SP, Brazil) were divided into two groups, which consumed 11.3 g of UBF or 4 g of maltodextrin, three times a week during six weeks with a washout period of 30 days. The bowel function was assessed by the Gastrointestinal Symptom Rating Scale and by a daily bowel function questionnaire with the Bristol Stool Scale. It were also evaluated the quality of life by the Medical Outcomes Study Questionnaire 36 - Item Short Form Health Survey and plasma concentrations of fasting glucose, insulin, total cholesterol and its fractions, triglycerides, potassium and phosphorus. The consumption of UBF led to significant reduction of abdominal distension (p = 0.019), flatulence (p = 0.021), hard stools (p = 0.008) and feeling of incomplete bowel evacuation (p = 0.000). In the first week of UBF consumption, patients related an increased number of evacuation (p = 0.003) and better stool consistency (p = 0.001). It was observed no differences in quality of life. The concentrations of fasting plasma glucose (p = 0.012) and potassium (p = 0.020) were significantly reduced. As the constipation is one of the predominant complaints of diabetic patients treated with hemodialysis, unripe banana flour can contribute effectively to the treatment of this symptom and additionally improve important biochemical parameters in the treatment of these patients.
414

Roteiro de inspeção das boas práticas de fortificação em moinhos de trigo / Good Manufacturing Practices checklist for the inspection of mills that fortify wheat flour

William Cesar Latorre 22 October 2009 (has links)
O governo brasileiro adotou a fortificação de farinhas de trigo com ferro para auxiliar na redução da anemia no país. Esta intervenção não está administrada como um programa sanitário coordenado, com monitoramento de atividades e avaliação de impacto. Essas ações têm ocorrido na forma de pesquisa acadêmica dispersa no país, e têm focado na compreensão da estratégia pelos moinhos de trigo, no monitoramento da concentração de ferro nas farinhas do mercado, e na avaliação do impacto sobre a saúde de grupos vulneráveis à anemia. Os resultados dessas pesquisas levam a pensar num trabalho coordenado, com avaliações padronizadas sobre alvos adequados, e na necessidade de instrumentos específicos de monitoramento da fortificação para a indústria e para a fiscalização sanitária. O objetivo deste trabalho foi elaborar um roteiro de verificação das Boas Práticas de Fabricação de farinhas enriquecidas com ferro em moinhos de trigo, que incluísse diretrizes para procedimentos operacionais padronizados de fortificação, nas hipóteses da existência de grande diversidade tecnológica de fortificação nos moinhos, e na necessidade deste checklist pela fiscalização para auditar esse processo. A padronização desses procedimentos é imprescindível para a efetividade do combate a anemia, porque normaliza a qualidade dos produtos fortificados, tornando-os mais homogêneos. Para elaborar o roteiro de verificação foi realizada uma pesquisa bibliográfica científica e de regulação, sobre Boas Práticas de Fabricação. Um roteiro inicial, para uma pesquisa de observação da indústria do trigo, foi extraído das legislações da vigilância sanitária, inclusive do programa nacional de fortificação do sal com iodo. A partir desse roteiro, entre 2007 e 2008, o pesquisador realizou uma pesquisa etnográfica em 11 moinhos de trigo no estado de São Paulo e elaborou uma lista de verificação de procedimentos operacionais de fortificação, contando com a colaboração de 20 profissionais de vigilância sanitária, convidados para aplicar o roteiro de BPF e apresentar parecer sobre o instrumento elaborado. Eles receberam do pesquisador uma capacitação em tecnologia de produção de farinhas em moinhos de trigo e posteriormente, colaboraram na elaboração e avaliação da efetividade do instrumento, acompanhando o pesquisador nas observações dos moinhos. O resultado é uma extensa lista de verificação das Boas Práticas de Fabricação em moinhos de trigo, com atenção às operações de fortificação das farinhas, que incluem procedimentos de dosagem e homogeneização de micronutrientes altamente diluídos na farinha, e de controles de qualidade de formulações de fortificantes e produtos finais, inclusive o registro de todas as informações. No checklist são indicados procedimentos operacionais padronizados de fortificação de farinhas e também, a amostragem para análise laboratorial da concentração de ferro e ácido fólico baseado no volume de moagem de trigo diário do moinho. A lista de verificação incluiu observações de moinhos de grande porte, que utilizavam diferentes sistemas de dosagem (volumétricos e gravimétricos) dos compostos de micronutrientes, controlados por procedimentos desde mecânicos até eletrônicos. Observações de laudos analíticos de farinhas levaram a concluir que existe ampla faixa de variação na concentração de micronutrientes entre as amostras analisadas. A qualidade dos resultados pode ser atribuída à baixa freqüência de controle dos sistemas de dosagem de menor automação, ao ponto de dosagem dos fortificantes que provoca pouca homogeneização da farinha fortificada, e à qualidade do composto de micronutrientes. Para melhorar a confiabilidade dos resultados de análise de ferro e ácido fólico são indicados procedimentos padronizados para análises laboratoriais com métodos analíticos validados. Concluiu-se que o método de observação participativa dos moinhos catalisou o conhecimento do pesquisador sobre a cultura do setor moageiro do trigo, fornecendo uma coleção significativa de itens de observação, que influenciam a qualidade dos procedimentos de fortificação. O checklist resultante de Boas Práticas de Fabricação enfocado na fortificação de farinhas contempla a variedade de situações tecnológicas observadas no mercado do estado de São Paulo e sugere-se sua utilização pelos moinhos de trigo para monitorar a produção de farinhas fortificadas e pela vigilância sanitária para auditorias e inspeções dos procedimentos industriais de fortificação. / The Brazilian government adopted the compulsory fortification of wheat flour with iron and folic acid to help reduce the iron deficiency anemia in the country. This intervention is not managed as a centralized sanitary program, with specific activities to monitor and to evaluate the impact on the health of a target population. These actions are being performed as a country spread academic research, on: the understanding of the intervention by wheat mills managers; the monitoring of the iron and folic acid concentration on samples of wheat flour for bakery and domestic use; and the evaluation of the intervention impact on the health of anemia vulnerable groups. The results of these researches make us think about a coordinated work, with standardized evaluations on adjusted targets, and specific instruments for monitoring the fortification process in the mills, and to be adopted by the sanitary inspection. The objective of this dissertation is to draw up a checklist for the inspection of the Good Manufacturing Practices of wheat mills focused in the production of iron fortified flour, including directions for the standardization of the fortification processes, in case there is great technological diversity in the mills in the country. In addition, it is useful to provide public health agents with a checklist for sanitary inspection. The standardization of the fortification processes is essential for the effectiveness of the fight against anemia, because it brings the quality of the fortified products into line, thus making them more homogeneous. To draw up the checklist, a scientific and regulatory bibliographical research was conducted on Good Manufacturing Practices. An initial checklist to make the first observation of the wheat mills was obtained from the Sanitary Surveillance Agency legislation, including the national program for fortifying salt with iodine. Between 2007 and 2008, the researcher conducted an ethnographic research in 11 wheat mills in the state of São Paulo, using the initial guideline, and elaborated the checklist for the inspection of the flour fortification operational procedures, counting on the contribution of 20 professionals of the Sanitary Surveillance system, who were invited both to use the checklist and to give their expert remarks. The researcher shared his knowledge and trained these professionals on wheat flour technology, and after that they could better collaborate to test the effectiveness of the checklist, accompanying the researcher during the wheat mills observation trip. The result is a comprehensive checklist for Good Manufacturing Practices in wheat mills, with special focus on the operations to fortify flour, including dosage and dilution of micronutrients, and quality control of micronutrients and fortified flours, including the registration of all information. The checklist highlights the standardized operational procedures for flour fortification and the sampling for laboratory analysis of iron and folic acid contents, based on the daily grinding volume of wheat in the mill. The checklist includes observation of big mills that used different systems for dosaging micronutrients (volumetric and gravimetrical), controlled by mechanic and electronic procedures. The analysis of some analytical reports on flours showed a considerable variation in the concentration of micronutrients of the samples. These results can be attributed to the infrequent control of the dosage systems of micronutrients; the point of dosage of fortifiers in the production line, thus impairing homogenization of the flour; and to the quality of the micronutrient compounds. To improve the reliability of lab results for iron and folic acid, some standardized procedures with validated analytical methods are recommended. As a conclusion, the ethnographic research method of participant observation of wheat mills has accelerated the researcher´s knowledge of the culture of the wheat milling sector. This approach brought significant information on items to be observed that influence the quality of the fortification process. The Good Manufacturing Practices checklist focused on the fortification of flour included a variety of technological situations observed in the state of São Paulo. We suggest its use for monitoring the production of fortified flours by the mills, and for inspections of the fortification procedures by the Sanitary Surveillance system.
415

Fizičke i senzorske karakteristike funkcionalnih prehrambenih namaza na bazi celuloznih hidrokoloida i brašna pogače uljane tikve / Physical and sensory characteristics of functional food spreads based on cellulose hydrocolloids and flour of pumpkin seed cake

Nikolić Ivana 13 October 2015 (has links)
<p>Osnovni cilj ovog istraživanja je utvrđivanje mogućnosti proizvodnje funkcionalnog niskoenergetskog prehrambenog namaza na bazi bra&scaron;na od semena tikve golice i hidrokoloida ugljenohidratnog porekla.<br />Utvrđivanju ove mogućnosti prethodilo je potpuno karakterisanje i definisanje sastavnih komponenti namaza. To su bra&scaron;no od semena tikve golice i prehrambeni hidrokoloidi na bazi vlakana. Bra&scaron;no od semena tikve golice analizirano je radi određivanja njegovih fizičko&ndash;hemijskih karakteristika, funkcionalnih svojstava, mikrobiolo&scaron;ke ispravnosti i mikrostrukturalne prirode. Analizama bra&scaron;na stečen je uvid u fizičke, nutritivne i mikrobiolo&scaron;ke karakteristike i u svojstva pona&scaron;anja, s ciljem utvrđivanja mogućnosti primene bra&scaron;na od semena tikve u daljem radu. Takođe, ispitane su dve vrste hidrokoloida ugljenohidratnog porekla metodom mikrostrukturalne analize, metodom određivanja raspodele veličina čestica, reolo&scaron;kim određivanjima i teksturalnim karakterisanjem sistema. Cilj ovog ispitivanja je definisanje vrste i koncentracije vlakana u gel strukturi hidrokoloida, koja ima sposobnost da ostvari ulogu nosača bra&scaron;na, odnosno kontinualne faze u namazu. Time je predviđeno i pona&scaron;anje ugljenohidratnih hidrokoloida u prehrambenom sistemu tipa namaza.<br />Nakon definisanja sastavnih komponenti, radi utvrđivanja optimalnih svojstava namaza, analizirani su namazi sa različitom vrstom i koncentacijom vlakana u gel sistemu i različitim udelom primenjenog hidrokoloida u sastavu namaza. Pri ispitivanju značajnosti uticaja promenljivih faktora na svojstva dobijenih namaza kori&scaron;ćena je metoda planiranja eksperimenta (DOE&ndash;design of experiment) u okviru koje je primenjen potpuni faktorijalni dizajn. Takođe, međusobna linearna zavisnost<br />između pojedinih promenljivih određena je metodom korelacije sa ciljem utvrđivanja povezanosti parametara senzorske analize sa instrumentalno određenim karakteristikama.<br />Cilj objedinjenja svih analiza je definisanje sastava namaza optimalnih svojstava i formulacija niskoenergetskog prehrambenog namaza na bazi bra&scaron;na od semena tikve.<br />Na osnovu prikazanih rezultata istraživanja u okviru ove doktorske disertacije izvedeni su zaključci da je bra&scaron;no od semena tikve golice nutritivno i biolo&scaron;ki vrlo vredna sirovina dobre održivost, bez patogenih mikroorganizama i da predstavlja pogodnu sirovinu za proizvodnju namaza. Takođe, hidrokoloid Vivapur MCG 611F se odlikuje<br />povoljnijim reolo&scaron;kim i teksturalnim svojstvima od hidrokoloida Vitacel WFG HS73, jer tiksotropno protiče, ima veći stepen uređenosti i povezanosti strukture sa izraženom elastičnom prirodom koja mu omogućava manju podložnost deformacijama i čini ga pogodnim za proizvodnju namaza.<br />Na osnovu analize uticaja promenljivih faktora, koji se odnose na sastav namaza, zaključeno je da posmatrani namazi predstavljaju realne reolo&scaron;ke sisteme i da sastav namaza izraženo utiče na njihove reolo&scaron;ke, teksturalne i senzorske osobine.<br />Na osnovu sprovedenih istraživanja zaključuje se da je moguća proizvodnja niskoenergetskog namaza na bazi bra&scaron;na od semena tikve golice. Pri tome namaz treba da sadrži 80% MCG zamenjivača masti (na masu namaza) koncentracije hidrokoloidnog gela 7% i 20% bra&scaron;na od semena tikve golice (na masu namaza). Namaz optimalnih svojstava je polidisperzan sistem sa uređenom strukturom u<br />kojoj su čestice primenjene količine bra&scaron;na uklopljene u kontinuiranu mrežu hidratisanih MCG vlakana i potpuno obložene dostupnom količinom zamenjivača masti. Zahvaljujući takvoj organizaciji i strukturi sistema optimalni namaz ispoljava dobre reolo&scaron;ke karakteristike, optimalnu mazivost, dobro prijanjanje na povr&scaron;inu i laku manipulaciju namazom tokom proizvodnje i tokom primene. Dobijeni namaz predstavlja nutritivno vredan proizvod koji se na osnovu sastava i zdravstvenog uticaja komponenti može svrstati u funkcionalne prehrambene proizvode.</p> / <p>The main objective of this study was to determine the possibility of production the low-fat functional food spreads based on flour of pumpkin seed and carbohydrate<br />hydrocolloids.<br />That included complete characterization of components of the spreads, the flour of hull&ndash;less pumpkin seed and fiber based food hydrocolloids. Flour of pumpkin seed was analyzed in order to determine its physico&ndash;chemical characteristics, functional characteristics, microbiological safety and microstructural nature. These analyses of flour defined the physical, nutritional and microbiological characteristics and behavior of flour, with the aim of determine the possibilities of its application in further work.<br />Also, two types of carbohydrate based hydrocolloids were examined by microstructural aspect, by particle size distribution, rheological determinations and textural characterization. The aim of these analysis was to define the type and concentration of fibers in the gel structure of hydrocolloids, which has the ability of to flour carrier and the role of continuous phase in the spread. This predicted<br />the behavior of carbohydrate based hydrocolloids in the food system such as spreads.<br />The determination of main components of the spreads was followed by determination of optimal properties of the spreads, which included analysis of spreads with different type and concentrations of fibers in the gel system and the<br />different amount of the applied hydrocolloid. To determine the significance of the influence of variable factors on the properties of the obtained spreads, the method of design of experiment (DOE) was used, with applied full factorial design. Also, correlation between certain sensory and instrumentally determined parameters was defined.<br />The aim of all analysis was to define the composition of the spread with optimal properties and to formulate the low&ndash;fat food spread based on flour of pumpkin seed<br />Based on the results obtained within this doctoral thesis, it was concluded that the flour of pumpkin seed cake is nutritionally and biologically very valuable raw material<br />with good sustainability, without pathogenic microorganisms, thus it is a suitable raw material for the production of spread. Also, Vivapur MCG 611F was characterized as hydrocolloid with better rheological and textural properties than the hydrocolloid Vitacel WFG HS73, because of its thixotropic flow properties, higher degree of<br />networking and pronounced elastic nature of structure that provides lower susceptibility to deformation and makes it suitable for the production of spread.<br />Based on the influence of variable factors, related to the composition of spreads, it was concluded that the observed spreads were real rheological systems and that the<br />composition of spreads signifficantly influenced on their rheological, textural and sensory characteristics. Obtained resultes of this research suggested that the production of low&ndash;fat food spread based on flour of pumpkin seed is possible. This spread contains 80% of MCG 611F fiber based hydrocolloid ( on the mass of the spread) with gel concentration of 7% and 20% of flour of pumpkin seed cake ( on the mass of the spread). The spread with optimal properties is poydisperse system with compact structure in which the flour particles are incorporated into continious network of hydrated MCG fibers and completly coated with avaliable amount of fat relacer. Due to this organization and structure of the system, optimal spread exhibits good properties for manipulation during production and application, such as good rheological characteristics, optimal spreadability and good adhesion to the surface. Obtained spread is nutritionaly valuable food product which can be classified into functional food product based on the composition and health inffluance.</p>
416

Autentičnost cerealija i pseudocerealija – razvoj novih metoda analize brašna i gotovih pekarskih proizvoda / Authenticity of cereals and pseudocereals -development of new methods for the analysis of flour and final bakery products

Pastor Kristian 05 March 2018 (has links)
<p>U ovoj doktorskoj disertaciji analizirano je bra&scaron;no strnih žita (p&scaron;enice, spelte, ječma,<br />raži, tritikalea, ovsa), prosolikog žita (kukuruza) i pseudocerealija (heljde i<br />amarantusa) primenom gasne hromatografije sa masenom spektrometrijom (GC-MS) u<br />kombinaciji sa multivarijantnom analizom, u cilju ispitivanja mogućnosti za<br />određivanje autentičnosti navedenih biljnih vrsta. U tu svrhu, iz bra&scaron;na navedenih<br />cerealija i pseudocerealija ekstrahovani su mali molekuli (lipidi i &scaron;ećeri). Lipidne<br />komponente bra&scaron;na ekstrahovane su heksanom. Nakon vi&scaron;estrukog obezma&scaron;ćivanja<br />istih uzoraka bra&scaron;na heksanom i su&scaron;enja, usledila je ekstrakcija &scaron;ećernih komponenata<br />96%-tnim etanolom. Dobijeni heksanski i etanolni ekstrakti derivatizovani su<br />odgovarajućim reagensima. Za derivatizacaju lipidnih komponenata kori&scaron;ćen je<br />rastvor TMSH (trimetilsulfonijum hidroksida, 0,2 M u metanolu). Time se masne<br />kiseline prevode u odgovarajuće metil-estre. Za derivatizaciju &scaron;ećernih komponenata<br />kori&scaron;ćen je etanolni rastvor natrijum-hidroksida i hidroksilamin-hidrohlorida u<br />kombinaciji sa BSTFA (bis-(trimetilsilil-trifluoroacetamidom). Na taj način su prosti<br />&scaron;ećeri prevedeni u odgovarujuće trimetilsilil-oksime. Ovako pripremljeni ekstrakti<br />uzoraka bra&scaron;na su analizirani na GC&ndash;MS uređaju.<br />Dobijeni hromatogrami međusobno pokazuju veliku sličnost, a naročito u okviru<br />uzoraka iste botaničke vrste. U obradi hromatograma i masenih spektara, kori&scaron;ćen je<br />MSD Productivity ChemStation program uz primenu Wiley 275 biblioteke masenih<br />spektara. Dobijeni podaci analizirani su na tri načina. Prvi način podrazumeva<br />kreiranje numeričkih matrica u modu ukupne jonske struje (TIC). Drugi postupak<br />podrazumeva kreiranje numeričkih matrica izolovanjem karakterističnih fragmentnih jona sa hromatograma (kod lipida 74 m/z, a kod &scaron;ećera 73 m/z u kombinaciji sa bar<br />jednim od sledećih jona: 204 m/z, 217 m/z, i 361 m/z). Kod trećeg načina obrade<br />podataka, analiza je urađena kreiranjem matrica primenom binarnog sistema (1/0), gde<br />&bdquo;1&ldquo; označava prisustvo određene komponente, a &bdquo;0&ldquo; označava njeno odsustvo u<br />posmatranom uzorku. Tako dobijeni podaci podvrgnuti su multivarijantnoj analizi<br />primenom statističkih programa &ndash; PAST i STATISTICA. U sva tri slučaja ispitivani<br />uzorci grupisani su u međusobno jasno odvojene grupe, prema odgovarajućoj biljnoj<br />vrsti. Uočeno je jasno razlikovanje pseudocerealija (heljde i amarantusa) i prosolikog<br />žita (kukuruza) od grupe strnih žita (p&scaron;enice, spelte, ječma, raži, tritikalea i ovsa).<br />Primenjenim metodama postiže se manje selektivna klasifikacija biljnih vrsta u okviru<br />strnih žita, sa izuzetkom uzoraka ovsa i spelte. Ovi rezultati pokazuju da je novim<br />navedenim postupcima moguće utvrditi autentičnost bra&scaron;na različitih botaničkih vrsta<br />cerealija i pseudocerealija.<br />Na isti način tretirani su i uzorci proizvedenog hleba (kore i sredine) u kojima je<br />p&scaron;enično bra&scaron;no supstituisano sa 0, 20, 40, 50, 60, 80 i 100% heljdinog bra&scaron;na.<br />Multivarijantnom analizom GC-MS podataka dobijaju se jasno odvojeni klasteri u<br />skladu sa porastom udela bra&scaron;na heljde u kori i sredini hleba. Najbolji rezultati<br />postignuti su koreliranjem sastava i sadržaja ugljenohidratnih komponenata u kori<br />hleba.<br />Krajnji ishod razvoja ovih novih originalnih metoda je mogućnost njihove praktične<br />primene u cilju rutinskih kontrola kvaliteta bra&scaron;na i gotovih pekarskih proizvoda u<br />laboratorijama, proizvodnim pogonima i inspekcijskim službama. Posebna pogodnost<br />primene predloženih metoda je to &scaron;to su one semi-kvalitativnog i semi-kvantitativnog<br />karaktera, pa se mogu izvoditi bez tačne identifikacije eluirajućih malih molekula</p> / <p>In this doctoral thesis various flour samples of small grains (wheat, spelt, barley, rye,<br />triticale, oats), corn and pseudocereals (buckwheat and amaranth) were analyzed using<br />gas chromatography - mass spectrometry (GC-MS) in combination with multivariate<br />analysis, in order to examine the possibilities for determining the authenticity of the<br />plant species listed. Small molecules (lipids and sugars) were extracted from flour<br />samples of the above-mentioned cereals and pseudocereals. The lipid components of<br />the flour were extracted with hexane. The extraction of sugar components from the<br />same flour samples was performed with 96% ethanol solution, after multiple defatting<br />with hexane and drying of the samples. The obtained hexane and ethanol extracts were<br />derivatized with appropriate reagents. For the derivatization of the lipid components, a<br />solution of TMSH (trimethylsulfonium hydroxide, 0.2 M in methanol) was used. Thus,<br />the fatty acids were converted into the corresponding methyl esters. For the<br />derivatization of the sugar components, an ethanol solution of sodium hydroxide and<br />hydroxylamine hydrochloride combined with BSTFA (bis- (trimethylsilyl<br />trifluoroacetamide) was used. Thus, the free sugars were converted into the<br />corresponding trimethylsilyl oximes. The derivatized extracts prepared in this manner<br />were analyzed on a GC -MS device.<br />The obtained chromatograms were very similar, and especially within the samples of<br />the same botanical species. In the processing of the chromatograms and mass spectra,<br />MSD Productivity ChemStation program was used with the Wiley 275 Mass Spectra<br />Library. The obtained data were processed in three ways. The first method involves the<br />creation of numerical matrices in the total ion current mode (TIC). The second method<br />involves the creation of numerical matrices by isolating characteristic ion fragments from the TIC chromatograms (74 m/z for the lipid components, and 73 m/z in<br />combination with at least one of the following ions: 204 m/z, 217 m/z, and 361 m/z, for<br />the sugar components). In the third way of data processing, the analysis was done by<br />creating a matrix using a binary system (1/0), where &ldquo;1&rdquo; denotes the presence of a<br />particular component, and &ldquo;0&rdquo; denotes its absence in the observed sample. The data<br />thus obtained were subjected to multivariate analysis using statistical programs - PAST<br />and STATISTICA. In all three cases, the analyzed samples were grouped in clearly<br />separated groups according to the appropriate plant species. A clear distinction was<br />observed between pseudocereals (buckwheat and amaranth), corn and the group of<br />small grains (wheat, spelt, barley, rye, triticale, oats). The applied methods achieved a<br />less selective classification of plant species within the group of small grains, with the<br />exception of oats and spelt samples. These results show that it is possible to determine<br />the authenticity of flour of various botanical species of cereals and pseudocereals,<br />applying new methods described in this doctoral thesis.<br />The samples of produced bread (crust and crumbs) in which wheat flour was<br />substituted with 0, 20, 40, 50, 60, 80 and 100% of buckwheat flour were treated in the<br />same way. Multivariate analysis of GC-MS data provided clearly separated clusters in<br />accordance with the increase in the share of buckwheat flour in bread crusts and<br />crumbs. The best results were achieved by correlating the composition and content of<br />the carbohydrate components in bread crusts.<br />The ultimate outcome of the development of these new original methods is the<br />possibility of their practical application for the purpose of routine quality control of<br />flour and bakery products in laboratories, production facilities and inspection services.<br />A particular advantage of applying the proposed methods is that they are semiqualitative<br />and semi-quantitative. Therefore, they can be performed without the exact<br />identification of eluting small molecules (lipids and free sugars), nor their<br />quantification using analytical standards.</p>
417

Sobrecarga moderada de ferro em ratos: interação com frutanos e/ou fitato no metabolismo hepático e ósseo / Moderate iron overload in rats: interaction with fructans and/or phytate in hepatic and bone metabolism

Cocato, Maria Lucia 06 October 2008 (has links)
O excesso de Fe no organismo gera espécies reativas de oxigênio (ERO) que são potencialmente tóxicas. Entretanto, a magnitude dos efeitos da exposição à moderada sobrecarga de Fe e da sua interação com facilitadores e/ou inibidores da absorção mineral não é conhecida. O objetivo deste trabalho foi avaliar esses efeitos e a sua interação com fruta nos e/ou fitato (facilitadores e inibidores da absorção de Fe, respectivamente) nos índices séricos do estado nutricional em Fe, no perfil dos lipídeos séricos e em parâmetros do metabolismo hepático e ósseo. Para o experimento foram utilizados 34 ratos machos Wistar, pesando inicialmente 49,3 ± 3,9g, alojados individualmente em gaiolas de aço semimetabólicas por 92 dias. Uma dieta AIN-93G (Dieta 1: Grupo Controle) e quatro dietas AIN93G modificadas foram usadas para o estudo, com as seguintes características: Dieta 2: sobrecarga moderada de ferro com 550mgFe/kg de ração (Grupo SBC); Dieta 3: sobrecarga moderada de ferro + 18% de farinha de yacon (Grupo SBC+FY); Dieta 4: sobrecarga moderada de ferro + 0,6% de fitato (Grupo SBC+FIT); Dieta 5: sobrecarga moderada de ferro + 18% de farinha de yacon + 0,6 % de fitato (Grupo SBC+FY+FIT). Os resultados demonstraram que a moderada sobrecarga de Fe ou a sua interação com farinha de yacon e/ou fitato não alterou os índices séricos do estado nutricional em Fe. Ocorreu aumento na atividade sérica da AST apenas no grupo SBC (p=0,055). Nos grupos SBC e SBC+FY houve diminuição na concentração do colesterol sérico (p=0,002) e, apenas no grupo SBC+FY+FIT, diminuição da concentração sérica do VLDL. No fígado, houve aumento significativo (p=0,002) da concentração de Fe não-heme nos grupos IO (+83%) e SBC+FIT (+117%) e, em todos os grupos SBC, na atividade da enzima GPx (p=0,000). A atividade da CAT foi menor (p=0,036) apenas para o grupo SBC+FY+FIT. Em todos os grupos SBC ocorreu significativo aumento nos depósitos de hemossiderina em torno das células de Kupffer (p=0,000). Houve aumento na apoptose em todos os grupos SBC, com os grupos SBC+FY e SBC+FY +FIT apresentando o maior número de corpúsculos apoptóticos/área (+405% e +342%, respectivamente) (p=0,000). Não houve alteração nos parâmetros relacionados ao metabolismo ósseo. No grupo SBC+FY houve significativo aumento na absorção aparente de Ca (p<0,05). Conclusões: A moderada sobrecarga de Fe não alterou os índices séricos do estado nutricional em Fe, mas resultou em alterações no tecido hepático e no perfil dos lipídeos séricos. Com exceção do perfil de lipídeos séricos, no qual apenas o fitato pareceu exercer efeito protetor, nos demais parâmetros avaliados a interação com farinha de yacon rica em fruta nos e/ou fitato reverteu parcial ou totalmente as alterações induzidas pela moderada sobrecarga de Fe. / Excess Fe in the organism generates potentially toxic reactive oxygen species (ROS). However, the magnitude of the effects of a moderate Fe overload and its interaction with factors which inhibit or facilitate mineral absorption is not known. The aim of the present work was to evaluate such effects and their interaction with fructans and/or phytate (compounds which facilitate and inhibit Fe absorption, respectively) on serum iron status indices, on the profile of serum lipids and on hepatic and bone metabolism parameters. In the experiment, thirty-four male Wistar rats initially weighing 49,3 ± 3,9g were used. The rats were housed in individual stainless-steel wire-mesh cages for 92 days. An AIN-93G diet (Diet 1: Control Group) and four modified AIN-93G diets were used in the study. The modified diets presented the following formulations: Diet 2: moderate Fe overload with 550mgFe/kg diet (IO Group); Diet 3: moderate Fe overload + 18% yacon flour (IO-YF Group); Diet 4: moderate Fe verload + 0.6% phytate (IO-Phy Group); Diet 5: moderate Fe overload + 18% yacon flour + 0.6% phytate (IO-YF-Phy Group). The results demonstrated that a moderate Fe overload or its interaction with yacon flour and/or phytate did not alter the serum iron status indices. An increase in the serum AST activity was observed only in the IO group (p=0,055). In the IO and IO-YF groups, there was a reduction in the serum cholesterol concentration (p=0,002) and a reduction in the serum VLDL concentration was observed only in the IO-YF-Phy group. In the liver, there was a significant increase (p=0,002) in non-heme Fe concentration in the IO (+83%) and IO-Phy (+117%) groups. Also, GPx activity was significantly increased (p=0,000) in all IO groups. CAT activity was lower (p=0,036) only in the IO-YF-Phy group. A significant increase in hemosiderin deposition around Kupffer cells was observed in all IO groups (p=0,000). Apoptosis was increased in all IO groups, whereas the IO-YF and IO-YF-Phy groups showed the largest number of apoptotic bodies/area (+405% and +342%, respectively) (p=0,000). There was no alteration in the parameters related to bone metabolism. In the IO-YF group, there was a significant increase in Ca apparent absorption (p<0,05).Conclusions: The moderate Fe overload did not alter the serum iron status índices, but led to alterations in the hepatic tissue and in the profile of serum lipids. Except for the profile of serum lipids where only phytate seemed to have a protective effect, in the other evaluated parameters the interaction with yacon flour rich in fructans and/or phytate partially or totally reversed the alterations induced by the moderate Fe overload.
418

Stability of Whole Wheat Flour, Rolled Oats, and Brown Rice During Long-Term Storage and Preparation

Scott, Victoria Elizabeth 01 December 2015 (has links)
Whole grains are an increasingly popular health food in America. However, shelf life of whole grains is compromised due to the presence of lipoxygenases in the bran and germ, which lead to rancidity and generation of oxidative byproducts. These byproducts reduce sensory quality and may have a degradative effect on vitamins in whole grain products. The purpose of this study was to determine the degree of lipid and vitamin degradation during long-term storage of three whole grains: whole wheat flour, brown rice, and rolled oats. We also examined vitamin loss after cooking to determine if oxidative byproducts had an effect on vitamins during typical household cooking. Whole wheat flour, brown rice, and rolled oats were stored for 12 months and periodically analyzed for conjugated dienes, free fatty acids, tocopherols, thiamin, and riboflavin. Whole wheat bread, steamed brown rice, and oat porridge were made from samples stored for 0 months and 12 months and were analyzed for thiamin and riboflavin. Conjugated dienes increased significantly only in rolled oats, while tocopherols decreased significantly in whole wheat flour and rolled oats and insignificantly in brown rice. Free fatty acids increased significantly in whole wheat flour and brown rice. Thiamin and riboflavin were stable in raw stored grains and cooked products made from stored grains with the exception of brown rice, in which we observed a significant decrease in thiamin after 12-month storage and cooking. These results suggest whole wheat flour, brown rice, and rolled oats experience significant lipid and tocopherol degradation, but it does not appear to affect thiamin and riboflavin in raw stored products. Cooking appears to cause degradation of thiamin after storage of brown rice, but thiamin and riboflavin were otherwise stable in these whole grains.
419

Effects of lupin kernel flour on satiety and features of the metabolic syndrome

Lee, Ya Ping January 2008 (has links)
[Truncated abstract] Obesity is now a major public health problem worldwide. More than half the Australian population is now overweight. This is an important public health concern primarily because of the impact of overweight and obesity on risk of diabetes, hypertension and cardiovascular disease. Many strategies have been proposed to fight the obesity epidemic. One possible strategy involves understanding of the role of dietary components in the control of food intake. In this regard, dietary protein and fibre appear to be the most satiating nutrients. Foods enriched in protein, replacing energy from carbohydrate, or dietary fibre can increase satiety and reduce energy intake in the short-term. Longer-term trials suggest benefits of increasing protein or fibre intake on weight loss and features of the metabolic syndrome. The effects of dietary approaches which increase both protein and fibre at the expense of refined carbohydrate are uncertain. A practical approach to increasing both protein and fibre content of processed foods is to incorporate high protein and fibre ingredients into high carbohydrate foods. Lupin kernel flour is a novel food ingredient derived from the endosperm of lupin. It contains 40 to 45% protein, 25 to 30% fibre, and negligible sugar and starch. Lupin kernel flour can be incorporated into refined carbohydrate rich foods such as bread to increase protein and fibre content at the expense of refined carbohydrate. ... Body weight was measured every 2 weeks throughout the 16 week intervention, and these data were analysed to determine whether there was any between group difference in the rate of change in weight over 16 weeks. Over 16 weeks, lupin bread compared to white bread resulted in a significant increase in protein (13.7 (2.3, 25.0) g/d) and fibre (12.5 (8.8, 16.2) g/d) intakes, and a decrease in carbohydrate intake (-19.9 (-45.2, 5.5) g/d). There was a significant difference between groups in the rate of weight change over the 16 weeks (P=0.05). However, at 16 weeks there was no significant effect on body weight (-0.4 (-1.3, 0.6) kg), fat mass (-0.5 (-1.2, 0.2) kg) or fat free mass (0.2 (-0.5, 0.8) kg). Plasma adiponectin and leptin were not altered. Mean 24 hour systolic blood pressure (-2.4 (-3.4, -1.3) mm Hg) and pulse pressure (-3.1 (-3.9, -2.3) mm Hg) were lower for lupin relative to white bread, but diastolic blood pressure was not significantly different between groups. Apart from a lower HDL cholesterol for lupin relative to white bread (-0.09 (-0.17, -0.01) mmol/L), there were no significant differences in other blood lipids and glucose and insulin concentrations. Interpretation of the results was not influenced after adjustment for potential confounding factors. These studies assessed effects of bread enriched in lupin kernel flour relative to white bread, resulting in a higher protein and fibre intake and lower refined carbohydrate intake. This increased satiety and reduced energy intake acutely, but did not significantly influence body weight over 16 weeks. Systolic blood pressure and pulse pressure were significantly reduced. There were no significant improvements in blood lipids or glucose and insulin concentrations. Therefore, increasing protein and fibre intake at the expense of refined carbohydrate using lupin kernel flour may benefit satiety and blood pressure. Longer-term trials incorporating weight loss may be needed to observe benefits on body weight.
420

Fusarium infection of bread wheat and subsequent mycotoxin contamination of milling products: Impact on quality parameters and composition of flour / Fusarium-Befall an Brotweizen und Kontamination der Mahlprodukte mit Mykotoxinen: Auswirkungen auf Qualitätsparameter und die Zusammensetzung des Mehls

Kreuzberger, Marie 17 November 2011 (has links)
No description available.

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