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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.
61

Sėmeninių linų tyrimai somatinių ir generatyvinių audinių kultūrose / Investigation of linseed flax in the cultures of somatic and generative tissues

Blinstrubienė, Aušra 17 January 2006 (has links)
Linseed flax studies in vitro were carried out at the Laboratory of Genetic – Biotechnological, Department of Crop Science and Animal Husbandry of Lithuanian University of Agriculture in 2002-2005, photomorphogenetic processes were investigated at the Laboratory of Plant Physiology of the Lithuanian Institute of Horticulture in 2004-2005. Optimal conditions for the dedifferentiation of linseed flax stem segments and hypocotyls cells and those of secondary differentiation in vitro were ascertained. Light technology of a solid body was used for investigation and an optimal combination of light parameters has been selected, promoting photomorphogenesis in vitro. Factors determining androgenesis and gynogenesis processes in vitro were evaluated and potential androgenic and gynogenic genotypes for the development of initial selection material were selected.
62

Veiksniai, įtakojantys sėmeninių linų morfogenezę in vitro / Factors affecting morphogenesis in vitro of linseed flax

Katauskytė, Lina 08 June 2006 (has links)
Study aim is to study endogenic and exogenic factors preconditioning morphogenesis of linseed flax in vitro. Linseed flax studies in vitro were carried out at the Laboratory of Genetic – Biotechnological of Lithuanian University of Agriculture in 2004-2006. Factors which influence morphogenetic capability of linseed flax cultivars ‘Lirina’, ‘Barbara’ and ‘Szaphir’ in tissue culture were investigated. Two different types of explants – stem segments and hypocotyls – of the three genotypes were cultivated in nutrient media differing in their macro and micro salts concentration, vitamins and different levels of growth regulators. Our results showed that intensity of morphogenesis was affected not only by exogenous growth regulators, but also by the type of explant and genotype. Hypocotyls-derived callus gave the better results than that stem-segment-derived callus on all tested media. Four-weeks-old callus showed the maximum shoot regeneration frequency. The best morphogenetic capabilities were demonstrated for cultivar ‘Szaphir’. The largest number of shoots was produced by all the cultivars on MSB5 nutrient medium supplemented with cytokinin 2iP (2.0 mg 1-1). The master’s final work comprises 50 pages, including 3 tables, 10 figures and 66 literature references.
63

Seed Coat Color in Flax (Linum usitatissimum L.) Conditioned by the b1 Locus, its Linkage with Simple Sequence Repeat Markers (SSRs) and its Association with Flower Shape, Flower Color, Fatty Acid Profile and Grain Yield

2015 January 1900 (has links)
Previously seed coat color in flax has been used as a phenotypic marker for specialty quality traits and currently there is an increasing demand to use seed coat color in flax to market flax for human and animal nutrition uses. Seed coat color was studied to 1) understand the inheritance of seed coat color conditioned by the b1 locus, to 2) understand the relationship of other important flax traits with seed coat color as well as to 3) identify markers that are linked to seed coat color for future marker assisted selection of seed coat color. Spearman’s rank correlation and an allelism test was used to show the inheritance of the alleles at the b1 locus. Bulked segregant analysis (BSA) was used to identify putatively linked markers with the b1 locus, these were then screened on the CDC Bethune x M96006 recombinant inbred line population. Furthermore, the CDC Bethune x M96006 and CDC Bethune x USDA-ARS Crystal recombinant inbred line populations were used to identify any important flax traits that had a significant relationship with seed coat color. It was shown that seed coat color conditioned by the b1 locus was stably inherited and that b1vg and b1 are allelic to one another. The results of the BSA showed that there were 17 candidates for linkage but when these markers were screened on the population only the Lu456 from linkage group (LG) six was identified to have linkage (χ²=3.90; P<0.05) with the b1 locus. Additionally, it was shown that the b1 seed coat color allele of the b1 locus had a pleiotropic effect on flower color and flower shape and that seed coat color was associated with linolenic fatty acid content. None of the traits examined were found to be associated with the b1vg allele of this locus. These results show that the b1 locus is likely present on linkage group six, more marker coverage on linkage group six of markers that are polymorphic between the two seed coat color parents would increase the accuracy of detection. Lastly, this study showed that plant breeders should consider using the b1vg allele that conditions the variegated seed coat color to mark unique lines with important combinations of traits because it sorted independently for seed quality traits. Whereas, the yellow seed coat color conditioned by the b1 allele was found to be associated with higher linolenic fatty acid content and the semi-lethality of this allele would make it not suitable for use in parental lines.
64

Phytoestrogen status in relation to sociodemographic factors and biomarkers of bone health in older Brisbane women

Hanna, Katherine Lavina January 2006 (has links)
Background: Phytoestrogens are diphenolic compounds found in plants with a structure and molecular weight similar to oestradiol which enables them to bind to the oestrogen receptor. Isoflavonoids occur mainly within the legume family with highest concentration in soybeans. Lignans are found in a range of plant foods and the richest known source is linseed. Few studies have been published on intake of isoflavonoids and none were located on intake of lignans in Australian women. The validity of methods designed to estimate intake can be assessed using urinary excretion of isoflavonoids and lignans as studies have found an association between intake and excretion of isoflavonoids and lignans. It has been proposed that, through their ability to act like oestrogen, phytoestrogens could decrease bone turnover and attenuate the loss of bone mineral density (BMD) at menopause. The aims of this research were to determine the pattern of intake of isoflavonoids and lignans in 500 women from food and supplements and to assess a questionnaire used to estimate intake using excretion in a sub-sample of 141 women. Associations between usual intake or excretion of isoflavonoids and lignans and biomarkers of bone health were also examined. Methods: A cross-sectional study was conducted involving 500 women aged 40-80 years participating in the Longitudinal Assessment of Ageing in Women (LAW), a 5 year study being conducted in the Betty Byrne Henderson Centre at the Royal Brisbane and Women's Hospital. Subjects were randomly selected from the electoral role and stratified into ten year age groups. Intake of isoflavonoids and lignans from food and supplements was assessed using a specially designed questionnaire containing 110 items. Values for individual items were obtained from published literature and summed to provide average daily intakes of isoflavonoids and lignans (mg/d). A sub-sample of 141 women was recruited to take part in the assessment of the association between phytoestrogen intake and excretion. Participants collected three 24-h urine samples spaced over one week. Samples were analysed using high performance liquid chromatography MS/MS for seven isoflavonoids and four lignans. Bone mineral densities (BMD) of the femur neck, total hip and lumbar spine were measured by dual energy x-ray absorptiometry. Bone formation was assessed using serum bone alkaline phosphatase (bone ALP) and osteocalcin (OC) and bone resorption was assessed using deoxypyridinoline (DPD) and urinary excretion of N-terminal cross-linking telopeptide of type-I collagen (NTX). Potential confounding factors were also evaluated. Statistical analyses were conducted using SPSS for windows (version 10). Participants were defined as consumers if they reported intake of one or more serves of soy or linseed in the prior month. Differences in socio-demographic and lifestyle characteristics between groups were assessed using ANOVA and Chi Square tests. Associations between intake and excretion of phytoestrogens were assessed using Spearman's rank-order correlations () for non-normal data. Phytoestrogen intake was categorised into four groups for the assessment of the association with markers of bone health. Associations between phytoestrogen excretion and markers of bone health were assessed using Pearson's product moment correlations for normal data (r) and Spearman's rank-order correlations for non-normal data. A value of P < 0.05 was taken as statistically significant. Results: Consumption of soy food was reported by 40% and consumption of linseed by 34% of women. Median (range) intakes among soy/linseed consumers for isoflavonoids, 3.87 (0-173) mg/d, and lignans, 2.40 (0.1-33) mg/d, were significantly higher than corresponding intakes among non consumers of 0.005 (0-2.6) and 1.57 (0.4-4.7) mg/d, respectively (P < 0.001). Soy/linseed consumers reported higher intakes of energy (P=0.043), dietary fibre (P=0.003) and polyunsaturated fat (P=0.004); and a higher level of physical activity (P=0.006), SEP (P < 0.001), education (P < 0.001) and supplement use (P < 0.001). Use of non-prescription supplements for menopause in the previous month was reported by 13% of women. A review of supplements available for treatment of menopause indicated that use of soy, red clover, black cohosh and sage could have a role in treatment of menopause symptoms. Evidence supporting the presence of oestrogenic components was available for soy and red clover isoflavonoids only. There was a significant association between intake and excretion of isoflavonoids within the total group (r=0.207, P < 0.05), with a stronger association in soy consumers (r=0.364, P < 0.01). Excretion of isoflavonoids was detected in women who did not report known intake of soy foods, suggesting isoflavonoids could be derived in small amounts from other plant foods or use of soy as an ingredient in processed foods. There was no significant association between intake and excretion of lignans, however both intake and excretion were associated with dietary fibre (r=0.303 and r=0.230, respectively, P < 0.01 for both). Bone ALP was higher among the very low isoflavonoid intake group (P=0.005) for the total sample (P=0.005) and women with BMI≤25 kg/m2 (P=0.002). Data also demonstrated an inverse association between excretion of isoflavonoids and NTX within women with BMI≤25 kg/m2 (r=-0.33, P < 0.05). There was a positive association between lignan excretion and bone ALP in the total sample (r=0.21, P < 0.05) which was strengthened in women with osteoporosis/osteopenia (r=0.41, P < 0.05) and a positive association between lignan excretion and DPD among women with BMI≤25 kg/m2 (ρ=0.28, P < 0.05) All associations remained significant after adjustment for confounding. Conclusions: Few women who chose phytoestrogen-rich foods consumed amounts similar to women with traditional soy-based diets although some achieved high intakes with supplements. Women who consumed soy or linseed foods differed in lifestyle and sociodemographic characteristics that could influence the association with disease in epidemiological studies. Results indicated that the phytoestrogen questionnaire was useful for assessment of isoflavonoids but was not acceptably precise for measurement of lignans. Findings suggest that there is an inverse association between isoflavonoid status and bone ALP and NTX although the precise mechanism of action has not been clarified. The association between lignan intake and bone is less well understood; however findings of a positive association with bone ALP indicate that further research on the lignan content of foods and the inclusion of lignans in studies is warranted.
65

Fornecimento de fontes lipídicas na dieta de poedeiras e seus efeitos sobre o desempenho, qualidade dos ovos, perfil de ácidos graxos e colesterol na gema

Faitarone, Ana Beatriz Garcia [UNESP] 17 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-17Bitstream added on 2014-06-13T19:04:39Z : No. of bitstreams: 1 faitarone_abg_dr_botfmvz.pdf: 754134 bytes, checksum: 45dd71e6381045c73eb898cfbd217a7f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O presente experimento teve duração de 112 dias e teve por objetivo avaliar o desempenho e qualidade dos ovos de poedeiras leves alimentadas com dietas suplementadas com óleos vegetais. As aves foram distribuídas em um delineamento experimental inteiramente casualisado com 10 tratamentos - (T1 – Controle; T2 – inclusão de 2,5% de óleo de linhaça; T3 – inclusão de 2,5% de óleo de canola; T4 – inclusão de 2,5% de óleo de soja; T5 – inclusão de 5% de óleo de linhaça; T6 – inclusão de 5% de óleo de canola; T7- inclusão de 5% de óleo de soja; T8 – inclusão de 2,5% de óleo de linhaça + 2,5% de óleo de soja; T9 – inclusão de 2,5% de óleo de canola + 2,5% de óleo de soja e T10 – inclusão de 2,5% de óleo de linhaça + 2,5% de óleo de canola) - e seis repetições de oito aves por parcela experimental, perfazendo um total de 480 aves. Foram avaliadas o consumo de ração, a produção de ovos, o peso dos ovos, a massa de ovos, a conversão alimentar por dúzia e por quilograma de ovos produzidos, a gravidade específica dos ovos, a resistência da casca à quebra, a cor de gema, as percentagens de gema, albúmen e casca, a espessura de casca e o índice gema. Não foram observadas diferenças significativas entre os tratamentos para peso e massa de ovos, conversão alimentar por dúzia de ovos produzidos, gravidade específica dos ovos, resistência da casca à quebra, espessura de casca, percentagens de gema, albúmen e casca. Concluiuse que a suplementação de óleos vegetais, na ração de poedeiras comercias leves não promoveu melhoras no desempenho e na qualidade dos ovos / The present experiment lasted 112 days and aimed to weigh up the performance and eggs quality of light laying hens fed with diets supplemented with vegetal oil. The light laying hens were distributed on an completely randomized design with 10 treatments (T1 - control, T2- inclusion of 2.5% of linseed oil in the diet, T3- inclusion of 2.5% of canola oil in the diet; T4-inclusion of 2.5% of soybean oil in the diet; T5- inclusion of 5% of linseed oil in the diet; T6- inclusion of 5% of canola oil in the diet; T7-inclusion of 5% oil soy in the diet; T8- inclusion of 2.5% of linseed oil +2.5% soybean oil in the diet; T9- inclusion of 2.5% canola oil + 2.5% soybean oil in the diet and T10- inclusion of 2.5% of linseed oil + 2.5% of canola oil in the diet) and six repetition of eight birds by experimental sector, adding up to 480 birds. The ration consumption, the eggs production, the weight and mass, the alimentary conversion per dozen and per kilogram of produced eggs, specific gravity of the eggs, the strength egg shell to break, the yolk color, proportion of yolk, albumen and shell, shell thickness and yolk index were weighed up. Significant differences among the treatments for weight and eggs mass, food conversion by produced dozen eggs, specific eggs gravity, resistance to shell break, shell thickness, percentages of yolk, albumen and shell were not observed. It was concluded that the vegetal oils supplementation on the given diets to light laying commercial hens doesn’t affect the performance and the eggs quality
66

Perfil de ácidos graxos e energia metabolizável aparente de diferentes fontes lipídicas para galinhas poedeiras

Araujo, Robert Guaracy Aparecido Cardoso January 2017 (has links)
Orientador: Valquíria Cação Cruz-Polycarpo / Resumo: É importante a determinação atualizada dos valores nutricionais dos alimentos para a prática de formulação de rações para aves. O objetivo desta pesquisa foi avaliar o perfil de ácidos graxos e energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) de diferentes fontes de óleos (soja, girassol, linhaça e peixe) para galinhas poedeiras da linhagem Hysex White, com 24 semanas de idade. As dietas experimentais consistiram de: T1 – ração basal, T2 – ração basal + 10% de inclusão de óleo de soja, T3 – ração basal + 10% de inclusão de óleo de girassol, T4 – ração basal + 10% de óleo de linhaça e T5 – ração basal + 10% de óleo de peixe, distribuídas num delineamento inteiramente casualizado com sete repetições e oito aves por unidade experimental. O perfil de ácidos graxos das fontes lipídicas foi analisado por cromatografia gasosa. O ensaio de digestibilidade foi realizado pelo método de coleta total de excretas, utilizando-se 280 poedeiras em 35 gaiolas experimentais, incluindo aves do grupo controle. Os resultados foram submetidos à análise de variância e as médias dos tratamentos foram comparadas pelo teste de tukey à 5% de probabilidade. Os maiores níveis de ácidos graxos insaturados foram encontrados nas fontes de origem vegetal, com mais de 80% enquanto o óleo de peixe apresentou 58,38%. Os valores de EMAn na matéria natural foram: 9.334 kcal/kg para o óleo de soja; 10.533 kcal/kg para o óleo de girassol; 10.928 kcal/kg para o óleo de linhaça e 9.005 kcal/... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
67

Efeitos da radiação ionizante de Cobalto-60 nas características físico-químicas, sensoriais e microbiológicas de pães com adição de linhaça (Linum usitatissimum) / Ionizing radiation effects of Cobalt-60 on the physical-chemical, sensorial and microbiological of bread with addition of linseed (Linum usitatissimum)

Neila Camargo de Moura 20 January 2012 (has links)
A incorporação de ingredientes funcionais a produtos de panificação tem crescido muito ultimamente, em função da preocupação com a saúde dos consumidores. A linhaça tem despertado o interesse pelo seu alto teor de fibras, lignanas, ômega-3 e compostos antioxidantes. O presente trabalho teve por objetivo avaliar o efeito da radiação ionizante de 60Co nas características físico-químicas, sensoriais e microbiológicas de pães com adição de diferentes concentrações de linhaça marrom. Foram elaborados 3 tipos de pães: pão francês, pão de forma preparado com pré-mistura e pão de forma elaborado com ingredientes (\"convencional\"). Foi adicionada linhaça marrom triturada na massa dos pães nas concentrações 8% e 12%. Após o preparo, os pães foram embalados em embalagem de polipropileno e levados ao Instituto de Pesquisas Energéticas Nucleares (IPEN/USP) e irradiados nas doses 6, 8 e 10 kGy. Foram elaborados tratamentos sem adição de linhaça e sem irradiação para controle, totalizando no experimento 12 tratamentos, para cada formulação de pão testado. Foram realizadas análises químicas (composição centesimal, compostos antinutricionais, atividade antioxidante, índice glicêmico, ácidos graxos, vitaminas do complexo B e minerais); análises físicas (índice de cocção, volume, cor e atividade de água); análise sensorial (teste de preferência e Análise Descritiva Quantitativa - ADQ); análise microbiológica e uma pesquisa de opinião sobre produtos irradiados. Observou-se que a adição de linhaça foi eficiente para aumentar o teor de fibras alimentares e o teor de lipídeos nas 3 formulações de pães. Os pães que receberam adição de linhaça e que não foram irradiados apresentaram aumento no teor de fenólicos totais, porém, ao submeter as amostras que receberam adição de linhaça ao processo de irradiação, observou-se diminuição da capacidade antioxidante. Houve aumento no teor de ômega 3 de acordo com a porcentagem de linhaça adicionada aos pães. A adição de linhaça foi eficiente para aumentar o teor de potássio, fósforo e magnésio. Porém a irradiação diminuiu o teor de vitamina B1 e vitamina B6 dos pães. A irradiação não influenciou na qualidade dos pães obtidos. Os provadores não treinados aceitaram os pães independentemente da dose de radiação aplicada. A ADQ evidenciou que as características sensoriais das amostras são dependentes da variação dos ingredientes utilizados nas formulações e da irradiação. As amostras irradiadas apresentaram contagens de bolores consideravelmente mais baixos que as amostra não irradiadas, o que aumentou o shelflife desses produtos. A pesquisa de opinião revelou que a maioria dos entrevistados tem pouco ou nenhum conhecimento sobre irradiação e acreditam que a irradiação pode trazer algum tipo de prejuízo ao humano. Portanto, a fabricação de pães enriquecidos com sementes de linhaça triturada e submetidos à radiação gama é promissora, uma vez que as propriedades químicas e sensoriais foram consideradas satisfatórias, além de terem o tempo de prateleira aumentado / The incorporation of functional ingredients on breading products has grown very much lately, because of the preoccupation with the consumers\' health. The linseed has awakened the interest by its high level of fiber, lignin, omega-3 and antioxidants compounds. The objective of the present work is evaluate the ionizing radiation effect of 60Co on the physical-chemical, sensorial and microbiological characteristics of bread with addition of different concentration of brown linseed. There were elaborated 3 types of bread: French roll, form bread prepared with the mixture and form bread produced with conventional ingredients. It was added smashed brown linseed on the bread dough, with concentrations of 8% and 12%. After the preparation, the three kinds of bread packed with polypropylene packages and taken to the IPEN/USP (Institute of Nuclear Energetic Research/University of São Paulo) and irradiated with doses of 6, 8 and 10 kGy. Treatments were elaborated without the addition of linseed and without irradiation, for control, totalizing 12 distinct treatments, to each bread formula tested. Chemical analyses were made (centesimal composition, anti-nutritional compounds, anti-oxidant activity, glycemic index, fat acids, complex B vitamins and minerals); physical analyses (cooking index, volume, color and water activity); sensorial analyses (preference tests and Descriptive Quantitative Analysis - ADQ); microbiological analysis and a survey about irradiated products. It could be seen that the addition of linseed was efficient to increase the level of alimentary fiber and the level of lipids on the 3 bread formula. The three kinds of bread that received the linseed addition and that were not irradiated presented increase on the level of total phenolic; however, when the samples which received the linseed addition were submitted to the irradiation process, it could be noticed the decrease of the antioxidant capacity. There was an increase on the level of omega-3, depending on the percentage of linseed added to the bread. The linseed addition was effective to raise the level of potassium, phosphorus and magnesium. But, the irradiation decrease the level of vitamin B1 and vitamin B6 of the three kinds of bread. The irradiation did not influence the quality of the obtained bread. The sample tasters, not trained, accepted the bread independently of the doses of applied radiation. The ADQ test evidenced that the sensorial characteristics of the samples depend on the ingredient variation used on the formulas and on the radiation. The irradiated samples presented mold counting considerably lower than the non-irradiated samples, which increased the shelf-life of those products. The survey reveals that the majority of the people interviewed has little or any knowledge about radiation and believe that the irradiation can generate some kind of harm for human beings. Therefore, the bread production enriched with mashed linseed and submitted to gamma radiation is promising, given that the chemical and sensorial properties were considered satisfactory, besides the increasing of the shelf-time
68

Estudo do efeito de autorreparação nos revestimentos aditivados com microcápsulas contendo óleo de linhaça. / Study of the self-healing effect of coatings additivated with microcapsules containing linseed oil.

Mónica Baptiste Restrepo 24 October 2012 (has links)
O objetivo deste trabalho foi a preparação de um revestimento inteligente com resina epóxi, capaz de autorreparar-se quando o sofre um defeito mecânico. A autorreparação é possibilitada pela presença de microcápsulas, dispersas na resina (revestimento de epóxi sem pigmentos) e que contêm no seu núcleo o agente de autorreparação, o óleo de linhaça. Estas cápsulas foram preparadas por uma emulsão de óleo de linhaça em água para formar micelas e sobre estas uma parede ou casca exterior de poliuréia-formaldeído. Para a avaliação da resistência à corrosão e do efeito de autorreparação do revestimento, chapas de aço carbono foram revestidas e avaliadas pela técnica de espectroscopia de impedância eletroquímica (EIE) em 0.1molL-1 1 NaCl e também foram avaliadas pelo teste acelerado de corrosão em câmara de névoa salina (SSC). Após a cura do revestimento aditivado com as microcápsulas, aplicado sobre placas de aço carbono, as medidas eletroquímicas de impedância foram realizadas em corpos de prova com um defeito mecânico provocado de forma controlada e reprodutível. Uma célula de três eletrodos foi utilizada. Estas medidas foram efetuadas após 0h, 24h e 48h da execução da incisão ou defeito mecânico. Para comparação, as mesmas medidas foram realizadas com as placas pintadas com o revestimento não-aditivado, com a mesma espessura total de 120 m. Os resultados mostraram que as cápsulas foram quebradas e se liberou o óleo de linhaça, reparando a área da incisão o defeito após pelo menos 24 horas de exposição natural ao ar ambiente. Verificou-se que para as placas revestidas sem defeito, os valores de | Z | mantiveram-se elevados. No entanto, o revestimento sem as microcápsulas, após 24 horas, mostrou uma diminuição considerável no valor de módulo de impedância, |Z|. Assim, usando a técnica de EIE foi possível avaliar quantitativamente o mecanismo de autorreparação do revestimento aditivado com microcápsulas que contêm óleo de linhaça. Os ensaios acelerados de corrosão (SSC) mostraram resultados em estreita concordância com os obtidos por EIE. / The aim of this work was the preparation of a smart coating with epoxy resin which is able to repair itself (self-healing effect) after suffering a mechanical defect. Self-healing is possible due to the presence of microcapsules, dispersed in the resin (clear type epoxy coating) and contain in their core the self-healing agent, the linseed oil. These capsules were prepared in an emulsion of linseed oil in water to form micelles and an outer skin or wall of poly(urea-formaldehyde) was formed. For the corrosion resistance and the self-healing effect evaluation of the coating, carbon steel plates were coated and tested by electrochemical impedance spectroscopy technique (EIS) in 0.1molL-1 NaCl solution and by accelerated corrosion test in salt spray chamber (SSC). After curing of the capsules additivated epoxy based clear coating applied on carbon steel plates, electrochemical impedance measurements were performed on plates with a controlled and reproducible mechanical defect. A three-electrode electrochemical cell was used. These measurements were performed after 0h, 24h and 48h of making the incision or mechanical defect. For comparison, the same measurements were performed with the plates painted with a non- capsules additivated clear coating of the same total thickness of 120 m. The results showed that the capsules were broken and released the linseed oil, which indeed have repaired the incision area after at least 24 hours of natural air aging. It was found that for the plates coated without a defect, the values of impedance modulus, |Z|, remained high. However, the coating without the capsules after 24 hours, showed a considerable decrease in |Z|. So, using EIS it was possible to quantitatively assess the mechanism of self-healing of the additivated coating using microcapsules containing linseed oil. The SSC accelerated corrosion tests showed results in close agreement with those obtained by EIS.
69

Reformulação do perfil lipídico de produto cárneo emulsionado adicionado de óleo de linhaça e ervas e especiarias = avaliação das características físico-químicas e sensoriais / Reformulation of the lipid profile of emulsified meat product with the addition of linseed oil and herbs and spices : evaluation of the physico-chemical and sensory

Ignácio, Ana Karoline Ferreira 08 May 2011 (has links)
Orientador: Marise Aparecida Rodrigues Pollonio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T16:44:45Z (GMT). No. of bitstreams: 1 Ignacio_AnaKarolineFerreira_M.pdf: 13650039 bytes, checksum: 86e2c4212924c9feca270a8406774621 (MD5) Previous issue date: 2011 / Resumo: O desenvolvimento de produtos alimentícios com propriedades mais saudáveis é uma das tendências mais relevantes na atualidade, favorecido por novas orientações nutricionais e por mudança de hábitos dos consumidores. A reformulação lipídica de produtos cárneos implementada pelo uso de componentes substitutos à gordura saturada, nesse contexto, tem sido tema de muitas pesquisas. Desta forma, o objetivo deste estudo foi avaliar os efeitos da adição de óleo de linhaça como substituto parcial de gordura suína em produto cárneo tipo mortadela sobre suas características físico-químicas e sensoriais. Inicialmente, foi realizado um delineamento fatorial composto central para determinar os efeitos do teor de gordura (5-20%) e do óleo de linhaça (2,5-12,5%) sobre a estabilidade da emulsão, perfil de textura, cor e aceitação sensorial. O teor de gordura influenciou os atributos firmeza e mastigabilidade em valores acima de 15% nas amostras. Os valores de L* e b* foram significativamente maiores (p<0,05) para as formulações contendo óleo de linhaça na maioria dos níveis avaliados. A adição do óleo de linhaça pré-emulsionado com caseinato de sódio contribuiu para a melhora da estabilidade do batter cárneo. Com relação às propriedades sensoriais, a adição de óleo de linhaça influenciou principalmente os atributos aroma, cor e sabor, resultando em notas menores nas formulações com óleo quando comparadas com a formulação controle. Posteriormente, foram estudadas diferentes ervas e especiarias como componentes antioxidantes para serem utilizadas na formulação de melhores resultados da fase anterior. As ervas que apresentaram maior efeito antioxidante foram o coentro, salvia e pimenta branca, segundo as melhores respostas em teste de oxidação lipídica acelerada. Foi também observado um efeito pró-oxidante na salsa. Na última etapa do estudo, uma formulação previamente selecionada na primeira fase com 60% de substituição da gordura suína por óleo de linhaça, adicionada de blends de ervas e especiarias com melhores resultados antioxidantes, foi avaliada através das. análises de perfis de ácidos graxos, cor, perfil de textura, estabilidade de emulsão, TBARS e aceitação sensorial. As amostras de uma forma geral apresentaram menores valores para firmeza e mastigabilidade em relação à formulação padrão. Os blends de ervas e especiarias influenciaram a cor objetiva com maiores valores de b* e menores de L* em relação à formulação padrão com óleo e sem ervas. Os blends de ervas e especiarias conferiram proteção antioxidante aos produtos até o 30º dia de armazenamento sob refrigeração. Houve um aumento considerável de PUFAs e uma diminuição na relação ?-6/?-3 na formulação estudada quando comparada à formulação controle, além de uma boa aceitação sensorial sem diferenças perceptíveis na textura e com notas semelhantes ao padrão para o sabor e o aroma. As características físico-químicas e sensoriais demonstram que é possível produzir uma mortadela mais saudável com um perfil lipídico favorável sob aspecto nutricional, com até 60% de substituição da gordura suína por óleo de linhaça, rico em ácidos graxos polinsaturados / Abstract: The development of food products with healthier properties is one of the more relevant current, favored by new nutritional guidelines for nutrition and changing habits of consumers. The reformulation of lipid meat products implemented by the use of substitute components to saturated fat in this context has been the subject of many investigations. Thus, the aim of this study was to evaluate the effects of addition of linseed oil as a partial replacement of pork fat in bologna sausage on its characteristics physical-chemical and sensory. Initially, was realized a factorial central composite design to determine the effects of fat content (5-20%) and linseed oil (2.5 to 12.5%) on the emulsion stability, texture profile, color and acceptance sensory. The fat content influenced the attributes firmness and chewiness at concentrations above 15% in the samples. The values of L * and b * were significantly higher (p<0.05) for formulations containing linseed oil in majority of the level evaluated. The addition of linseed oil pre-emulsified with sodium caseinate contributed to the improved stability of the meat batter. With respect to sensory properties, the addition of linseed oil influenced mainly attributes aroma, color and flavor, resulting in lower scores in the formulations with oil when compared with the control formulation. Later, was studied different herbs and spices as antioxidant compounds for use in the formulation with better results of the previous phase. The herbs with the highest antioxidant effect are coriander, sage and white pepper, referring the best answers to the test of accelerated lipid oxidation. It was observed a pro-oxidant effect in parsley. In the last stage of the study, a formulation previously selected in the first phase with 60% substitution of pork fat in linseed oil, plus blends of herbs and spices with the best results antioxidants, was evaluated by analysis of fatty acid profiles, color, texture profile, emulsion stability, TBARS and sensory acceptance.The samples generally showed lower values for firmness and chewiness than the standard formulation. The blends influenced in the objective color with higher values of b * and lower L * compared with standard formulations with oil and without herbs. The blends of herbs and spices conferred antioxidant protection to the products until the 30th day of refrigerated storage. There was a considerable increase of PUFAs and a decrease in the ratio ?-6/?-3 formulation studied when compared to the control formulation, besides good sensorial acceptance without noticeable differences in texture and notes similar to the standard for flavor and aroma. The physico-chemical and sensory characteristics demonstrated that it is possible to produce a healthier bologna sausage with a favorable lipid profile in the nutritional aspect, with up to 60% substitution of pork fat in linseed oil, rich in polyunsatured fatty acids / Mestrado / Tecnologia de Alimentos / Mestre em Tecnologia de Alimentos
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Efecto de una bebida alta en fibra sobre el nivel de trigliceridos en pacientes con dislipidemia de un hospital de Lima 2019 / Effect of a High-fiber drink on the level of triglycerides in patients with dyslipidemia of a hospital in Lima 2019

Del Castillo Vidal, Giuliana Rosa 14 August 2020 (has links)
Objetivo. Evaluar el efecto de una bebida alta en fibra a base de linaza, ajonjolí, avena y piña sobre los niveles de triglicéridos en pacientes adultos de un Hospital de Lima Perú. Materiales y método. Ensayo clínico controlado no aleatorizado, se enroló a 60 participantes adultos con diagnóstico de hipertrigliceridemia de un Hospital de Lima-Perú, y se asignó a tres grupos: a un grupo de 23 participantes se le administró una bebida alta en fibras en el hospital, 27 participantes consumieron la bebida alta en fibras en sus casas y a 10 participantes se le prescribió sólo dieta, la bebida y la dieta se administró por 05 días seguidos y se midió los niveles de triglicéridos al inicio y al final de la intervención. Resultados. El 60% fueron del sexo femenino y la edad media 51.11 DS= 13.51, el sexo masculino fue el 40% y la edad media fue 55.29, DS=10.0. El efecto de la bebida alta en fibra fue beneficiosa al reducir significativamente los niveles de triglicéridos en el subgrupo de pacientes que recibió el preparado en el hospital reduciendo los niveles de triglicéridos en 109.87 mg/dL p< 0.05) y en el subgrupo que preparó la bebida en sus casa los niveles de triglicéridos redujeron en 118.48 mg/dL, p< 0.05).En el subgrupo de pacientes que solo recibieron dieta los niveles de triglicéridos también disminuyeron en 80.90 mg/dL con un p<0.05. Cuando se comparó el grupo preparado en hospital y el grupo preparado por ellos mismos hubo (diferencia negativa de 8.6119, un error típico de 20.97, un p valor de 0,911 no significativo) pero con un mejor promedio para aquellos que recibieron la bebida en sus hogares. Conclusión. El efecto de la bebida alta en fibra fue beneficiosa al reducir significativamente los niveles de triglicéridos en el subgrupo de pacientes que recibió el preparado en el hospital y en el grupo que recibió la bebida en sus hogares, pero la diferencia entre ambos grupos no fue significativa. / Objective. To evaluate the effect of a high-fiber drink based on linseed, sesame, oats, and pineapple on triglyceride levels in adult patients at a hospital in Lima, Peru. Materials and methods. Non-randomized controlled clinical trial, 60 adult participants diagnosed with hypertriglyceridemia were enrolled from a hospital in Lima, Peru. They were assigned to three groups: A group of 23 participants was given a high-fiber drink at the hospital, 27 participants consumed the high-fiber drink at home, and 10 participants were prescribed diet only, the drink and diet were administered for 05 consecutive days, and triglyceride levels were measured at the beginning and end of the intervention. Results. 60% (36) were female and the mean age was 51.11 SD=13.51, and 40% (24) were male and the mean age was 55.29, SD=10.0. The effect of the high-fiber drink (based on linseed, sesame, oats, and pineapple) was beneficial in significantly reducing triglyceride levels by 109.87 mg/dL p<0.05 in the subgroup of patients who received the preparation at the hospital, and by 118.48 mg/dL, p<0.05 in the subgroup of patients who prepared the drink at home. In the subgroup of patients who only received diet, triglyceride levels also decreased by 80.90 mg/dL with a p<0.05. When comparing the group who received the preparation at the hospital and the group who prepared the drink themselves, there was a negative difference of 8.6119, a typical error of 20.97, a non-significant p-value of 0.911, but a better average for those who received the drink at home. Conclusion. The effect of the high-fiber drink was beneficial in significantly reducing triglyceride levels in the subgroup of patients who received the preparation at the hospital and in the group of patients who received the drink at home, but the difference between the two groups was not significant. / Tesis

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