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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.
1

An evaluation of the role of eggs and DATEM on the quality of gluten-free sorghum bread

Bize, Magali January 1900 (has links)
Master of Science / Food Science / Fadi Aramouni / Due to an increase in awareness of celiac disease, the gluten-free market continues to expand. However, gluten-free breads are still characterized by a poor structure and overall mediocre quality. This research was aimed at determining the impact of egg addition as well as an antistaling agent (DATEM) on the quality of a batter-based gluten-free sorghum bread. Gluten-free bread loaves containing 20, 25, or 30% eggs (as is) on a flour basis were evaluated against a control (no egg). The impact of the antistaling agent, DATEM at 0.5% was also studied for each of these formulations. Quality factors evaluated included water activity, color, specific volume, and cell size. Texture profile analysis was performed to evaluate staling rate based on changes in crumb hardness values and a trained panel evaluated staling attributes by descriptive analysis. Finally, a consumer acceptance test on sorghum bread with and without eggs was also conducted. Results showed that sorghum breads with eggs had higher specific volumes than control (increase from 0.06 cm[superscript]3/g to 0.11 cm[superscript]3/g), while DATEM had a negative effect on the volume of gluten-free bread (decrease of 0.73 cm[superscript]3/g). Eggs also improved cell structure and produced significantly darker crust (p<0.05). Additionally, the addition of eggs reduced bread hardness (from 54 g force to 142 g force on fresh bread) and slowed the rate of staling over the 12 day storage period studied. Descriptive analysis results confirmed the findings of the texture analysis, showing control bread significantly harder (p<0.05) than egg-containing bread at days 0 and 4. The consumer test indicated a significant preference (p<0.05) for sorghum bread with eggs over the control. The overall acceptability score for this bread was above 6 on a 1 to 9 hedonic scale. The score was closer to 7 when the bread was rated by consumers with celiac disease. This research proved that the addition of eggs to a gluten-free sorghum bread formulation resulted in delayed staling and better overall quality and acceptability of the product.
2

Effect of sorghum flour treated with ozone and heat on the quality of gluten-free bread and cake

Marston, Kathryn G. January 1900 (has links)
Master of Science / Food Science Institute, Animal Science & Industry / Fadi M. Aramouni / In order to improve the quality of products available for consumers who require a gluten-free diet, this study examined the effects of heat and ozone treatments on sorghum flour functionality in gluten-free bread and cake. In the ozone treatment experiment, commercially milled food-grade sorghum flour was subjected to ozone at the rate of 0.06 L/min for 15, 30, and 45 minutes. In the heat treatment experiment, commercially milled food-grade sorghum flour was subjected to dry-heat at two temperatures (95ºC and 125º) for 15, 30, and 45 minutes. Characterization of flour from each treatment included measurements of flour pH, color, and pasting properties. Evaluation of bread quality from each treatment included measurements of specific volume, color, crumb properties, and crumb firmness. Evaluation of cake quality from each treatment included measurements of specific gravity, volume, symmetry, uniformity, color, crumb structure, and crumb firmness. Bake testing using ozonated sorghum flour in a high-ratio white layer cake formulation showed that volume significantly increased (p<0.05) as ozonation time increased. Additionally, longer ozonation exposure times increased cells per slice area, lightness, and slice brightness values in gluten-free cakes while reducing crumb firmness. Despite improving lightness and slice brightness values, ozonation did not significantly increase (p>0.05) the specific volume of gluten-free batter based bread. In the heat treatment experiment, the optimum time and temperature relationship for improving sorghum flour was 125ºC for 30 minutes. This treatment level produced bread with the highest specific volume (3.08 mL/g) and the most cells per slice area (50.38 cells/cm2). This treatment level also produced cakes with the highest volume (72.17 cc) and most cells per slice area (79.18 cells/cm2). Additionally, cake and bread made from this heat treatment was deemed more acceptable in comparison to the control during consumer testing. The control sorghum flour in both studies produced breads and cakes with low volume, poor crumb properties, and dense textures. These results can assist in the product development process in advancing the quality of sorghum-based gluten-free foods for the consumers who require a gluten-free diet.
3

Glycemic Response to Gluten-Free Bread in Healthy Adults

January 2019 (has links)
abstract: Background: Research has found that nearly a quarter of the American population follows a gluten-free diet in some capacity, while only about 1% of the population is diagnosed with celiac disease. Although the amount of research-based evidence supporting any health benefits of a gluten-free diet in an individual without a gluten- related disorder is limited, the number of people claiming to follow a gluten-free diet continues to rise. Also, despite an increasing belief that gluten is harmful for health, the potentially undesirable effects of gluten substitutions used in gluten-free foods are largely unknown. Due to the protein network encapsulating starch granules, gluten is thought to lengthen the amount of time needed during starch digestion, thereby reducing postprandial glycemia. Therefore, it is predicted that breads containing gluten will produce a lower glycemic response compared to gluten-free breads. Aim: The aim of this study was to investigate the glycemic response of gluten-free bread made with different types of flour compared to bread made with gluten-containing wheat flour. Methods: This study involved a 3-week, randomized, single blind crossover study in which 17 healthy individuals were asked to consume a different type of bread each week, 2 of which were gluten-free. Blood glucose was taken by finger prick at fasting as a baseline measurement, then for 2 hours after bread consumption in 30-minute increments. Results: Across the three groups, there was no significant difference in iAUC values after 120 minutes (p=0.192 ). The greatest mean was seen in the gluten-containing bread (145.3 ± 82.6), then the gluten-free bread made with rice flour (125.5 ± 62.8), and lastly the gluten-free bread made with potato and fava bean flour (112.4 ± 64.5). Conclusion: The inconsistent results of this study compared to previous, similar studies suggests that the postprandial glycemic response of gluten-free products can not be generalized as a whole, but instead is dependent on the type of product and the ingredients used to replace the gluten. Although the results did not show a significant difference, it does argue against the belief that gluten-free products are invariably better for health in the general, non-gluten sensitive population. / Dissertation/Thesis / Masters Thesis Nutrition 2019
4

Properties of Malanga Flours and their Use in Pastes and Gluten Free Breads

Calle Domínguez, Jehannara 25 June 2021 (has links)
Tesis por compendio / [ES] El uso de Colocasia esculenta (L.) Schott y Xanthosoma sagittifolium (L.) Schott como materia prima en forma de almidón o harina es una alternativa sostenible y nutritiva al trigo y otros granos. Esta alternativa permite a los agricultores minimizar las pérdidas después de su cosecha y garantizar la seguridad alimentaria ya que sus propiedades nutricionales, digestivas y saludables son reconocidas por la comunidad científica. Sin embargo, la información existente sobre este rizoma dirigida a su aplicación es bastante limitada. Esta tesis expone la caracterización funcional y tecnológica de los almidones obtenidos a partir de cormos y cormelos de Xanthosoma sagittifolium (L.) Schott. Asimismo, se evaluó tecnológicamente el efecto de la combinación de enzimas, hidrocoloides, almidón de patata, harina pregelatinizada sobre la harina de los cormelos de la Colocasia esculenta (L.) Schott en el desarrollo de un pan sin gluten. Además, se evaluaron las propiedades tecnológicas y digestivas de una fórmula básica para puré desarrollada a partir de harina de cormelos de Xanthosoma spp. y Colocasia spp. Además, la revisión bibliográfica realizada permitió poner en contexto los efectos saludables demostrados clínicamente de esta materia prima y sus componentes. Se demostró que existen diferencias significativas entre el almidón de cormos y cormelos de la misma especie. Se concluyó que la harina de Colocasia esculenta (L.) Schott es una buena opción para incrementar el valor nutricional de los panes sin gluten. Entre las estrategias probadas, el pan elaborado a partir de la mezcla con almidón de patata resultó la menos aconsejable. Además, todas las estrategias aplicadas originaron panes con menor índice glucémico que sus homólogos sin gluten reportados en otros estudios. Por primera vez, este trabajo recomienda el uso de harina de cormelos de Xanthosoma sagittifolium (L.) Schott y Colocasia esculenta (L.) Schott y para desarrollar purés con un valor nutricional agregado. La revisión bibliográfica realizada permitió recopilar los efectos demostrados clínicamente, concretamente antihiperglucémicos, antihepatotóxicos, antihipertensivos, hipoglucemiantes, anticancerosos, hipolipidémicos y prebióticos, entre otros, de los compuestos bioactivos presentes en esta planta. / [CA] L'ús de Colocasia esculenta (L.) Schott i Xanthosoma sagittifolium (L.) Schott com a matèria primera en forma de midó o farina, és una alternativa per a minimitzar les perdues després de la seua collita i garantir la seguretat alimentària ja que les seues propietats nutricionals, digestives i saludables són reconegudes per la comunitat científica. Aquesta tesi exposa la caracterització funcional i tecnològica dels midons obtinguts a partir de corms i cormelos de Xanthosoma sagittifolium (L.) Schott. D'una banda és va avaluar tecnològicament l'efecte de la combinació d'enzims, hidrocol·loides, midó de creïlla, farina pregelatinitzada sobre la farina dels cormelos de la Colocasia esculenta (L.) Schott en el desenvolupament d'un pa sense gluten. D'altra banda, es van avaluar les propietats tecnològiques i digestives d'una fórmula bàsica per a puré desenvolupada a partir de farina de cormelos de Xanthosoma spp. i Colocasia spp. que es pot destinar a poblacions vulnerables amb afeccions gastrointestinals, diabètics, celíacs, entre altres. A més, es va realitzar una revisió on s'exposen els efectes saludables demostrats clínicament, dels seus components. Es va demostrar que existeixen diferències significatives entre el midó de corms i cormelos de la mateixa espècie. Per tant, es va concloure que la farina dels cormelos de la Colocasia esculenta (L.) Schott és una bona opció per a incrementar el valor nutricional dels pans sense glútens i entre les estratègies provades, el pa elaborat a partir de la mescla amb midó de creïlla va resultar la menys aconsellable, però tots van mostrar menor índex glucèmic que els seus homòlegs sense glútens reportats en altres estudis. A més, per primera vegada es va recomanar l'ús de farina cormelos de Xanthosoma sagittifolium (L.) Schott i Colocasia esculenta (L.) Schott per a desenvolupar purés amb un valor nutricional agregat. La revisió bibilogràfica realitza va permetre recopilar el efectes demostrats clínicament, en concret antihiperglucémic, antihepatotóxic, antihipertensiu, hipoglucemiant, anticancerós, hipolipidémic i prebiòtic, entre altres, dels compostos bioactius presents en aquest rizoma. / [EN] The use of Colocasia esculenta (L.) Schott and Xanthosoma sagittifolium (L.) Schott as a raw material in form of starch or flour is a nutritious and sustainable alternative to wheat and other grains. This alternative allows farmers to minimize losses after harvest and guarantee food safety since its nutritional, digestive and healthy properties are recognized by the scientific community. Nevertheless, there is still scarce information about these rhizomes that limit their application. This thesis illuminates the functional and technological characterization of the starches obtained from corms and cormels of Xanthosoma sagittifolium (L.) Schott. Likewise, the effect of the combination of enzymes, hydrocolloids, potato starch, pregelatinized flour on Colocasia esculenta (L.) Schott cormels flour toward the development of a gluten-free bread was technologically evaluated. Furthermore, the technological and digestive properties of a basic formula for pastes developed from cormels flour of Xanthosoma sagittifolium (L.) Schott and Colocasia esculenta (L.) Schott was evaluated. In addition, a review was conducted and the health effects clinically demonstrated are exposed. It was shown that there are significant differences between the starch of corms and cormels of the same species. It was concluded that the flour from Colocasia esculenta (L.) Schott cormels is a good option to increase the nutritional value of gluten-free breads. Among the strategies tested, the bread made from mixtures with potato starch was the least desirable, but all strategies tested gave breads with lower glycemic index than gluten-free counterparts reported in other studies. For the first time, this works recommends the use of cormels flour from Xanthosoma sagittifolium (L.) Schott and Colocasia esculenta (L.) Schott was recommended to develop pastes to nutritional value to gluten-free products. In addition, the bibliographic review carried out allowed the compilation and analysis of the clinically demonstrated effects, especifically, antihyperglycemic, antihepatotoxic, antihypertensive, hypoglycemic, anti-cancer, hypolipidemic and prebiotic effects, among others, of the bioactive compounds present in these plants. / Authors acknowledge the financial support of the Spanish Ministry of Science, Innovation and Universities (RTI2018-095919-B-C21), Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2-1-R), the European Regional Development Fund (FEDER) and Generalitat Valenciana (Project Prometeo 2017/189). Tropical Food Research Institute from Cuba provided the rhizomes. / Calle Domínguez, J. (2021). Properties of Malanga Flours and their Use in Pastes and Gluten Free Breads [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/168396 / Compendio
5

Otimização de propriedades nutricionais e sensoriais de produtos à base de amaranto enriquecidos com frutanos, para intervenção em celíacos / Nutritional and sensory optimization of amaranth based products enriched with fructans, for nutritional intervention in celiac

Capriles, Vanessa Dias 17 December 2009 (has links)
Introdução: A doença celíaca não tem cura e apresenta como único tratamento a dieta isenta de glúten. Frequentemente observa-se a má absorção de cálcio em celíacos, consequência dos menores níveis de transportadores de cálcio no enterócito desses indivíduos. Os celíacos têm dificuldade em dar sequência ao tratamento dietético devido à escassez de produtos isentos de glúten, tornando fundamental o desenvolvimento de produtos para esta população. Isso pode ser feito por meio do uso de matérias primas isentas de glúten e com valor nutritivo agregado, como o grão de amaranto, e de ingredientes que contribuem para o aumento da absorção de cálcio através de absorção passiva nos colonócitos, como os frutanos inulina e oligofrutose. Objetivo: Desenvolver e otimizar as propriedades nutricionais e sensoriais de produtos à base de amaranto enriquecidos com frutanos, para intervenção nutricional em celíacos. Metodologia: Foram elaborados snacks à base de milho e amaranto (50, 75 e 100%), barras e pães sem glúten, enriquecidos com 4 gramas de frutanos/ porção. Para maximizar a aceitabilidade das barras foi utilizado um planejamento experimental para misturas de amaranto extrusado, estourado e laminado. Para maximizar o valor nutritrivo e a aceitabilidade do pão sem glúten foi utilizado o planejamento experimental para misturas de farinha de arroz, fécula de batata e farinha de amaranto. Os produtos foram caracterizados quanto a composição centesimal, o índice glicêmico (IG) e a carga glicêmica (CG). Também foram avaliadas as propriedades físicas e a aceitabilidade (escala hedônica estruturada de nove pontos) durante o período de armazenamento. Resultados e discussão: Os snacks foram aceitos e apresentaram estabilidade de suas características físicas e da aceitabilidade durante os 135 dias de armazenamento. O efeito combinado do amaranto e dos frutanos gerou redução de 19% do IG e de 56% da CG dos snacks. O amaranto estourado e laminado apresentaram interações sinérgicas para a aceitabilidade das barras (R2(aj)>92%, p=0,00). A formulação à base de amaranto estourado e laminado (½,½) foi diversificada em seis diferentes sabores e apresentou estabilidade de suas propriedades físicas e da aceitabilidade durante os seis meses de armazenamento. A estimativa da resposta glicêmica revelou IG moderado e CG baixa das barras. Pães com 33 e 45% de farinha de amaranto apresentaram destacado valor nutritivo e aceitabilidade. A incorporação de amaranto e de frutanos ocasionou redução de 20% do IG e de até 53% da CG do pão sem glúten. Conclusão: Os produtos desenvolvidos (snacks, barras e pães sem glúten) apresentaram destacado valor nutritivo em relação aos produtos convencionais, atenuação da resposta glicêmica e alta aceitabilidade pelo consumidor, podendo contribuir para uma maior variação e adequação da dieta dos celíacos e também para auxiliar no aumento da absorção de cálcio / Introduction: Celiac disease does not have a cure and the only scientifically proven treatment is strict lifelong adherence to a gluten-free diet. Calcium malabsorption is frequently found in celiac, possibly due to negligible amounts of calcium-binding protein in their enterocytes. Compliance with dietary treatment is often difficult due to the lack of gluten-free products, so it is essential to develop specific products for this population. This can be done through the use of gluten-free raw materials of great nutritional value, such as amaranth grain, and ingredients that contribute to the calcium absorption increasement through passive absorption in colonocytes, such as the fructans inulin and oligofructose. Objective: Develop and optimize the nutritional and sensory properties of amaranth based products enriched with fructans, for nutritional intervention in celiac. Methods: Snacks from blends of corn and amaranth (50, 75 and 100%), amaranth bars and gluten-free bread, all enriched with 4 grams of fructans/ portion, were prepared. A mixture experiment of extruded, popped and flaked amaranth was used to optimize the sensory acceptability of the bars. A mixture experiment of rice flour, potato starch and amaranth flour was used to maximize the nutritional value and sensory acceptability of gluten-free bread. Products chemical composition, glycemic index (GI) and glycemic load (GL), were evaluated. The physical properties and sensory acceptability (nine point hedonic scale) were assessed during the storage time. Results and discussion: Snacks were sensory accepted and maintained their physical characteristics and sensory acceptability during the 135 days of storage. The combined effect of amaranth and fructans resulted in 19% reduction of GI and 56% of GL of snacks. Popped and flaked amaranth present synergistic interactions to sensory acceptability of the bars (R2(adj)>92%, p=0,00). Bars were produced with popped and flaked amaranth (½,½) in six different flavors and its physical properties and sensory acceptability were stable during the six months of storage. The predicted glycemic response showed moderate GI and low GL bars. Breads with 33 and 45% of amaranth flour had higher nutritional value and sensory acceptability. Amaranth and fructans addition led to a reduction of approximately 20% of GI and up to 53% of the GL of gluten-free breads. Conclusion: The developed products (snacks, bars and gluten-free breads) had superior nutritional composition than conventional products, reduced glycemic response, high consumer sensory acceptability, great potential to contribute to variation and adequacy of celiac diet and also help to increase calcium absorption.
6

Hodnocení kvality bezlepkových potravin se zaměřením na pečivo / Quality evaluation of gluten-free food, concretely gluten-free pastries

MARKO, Tomáš January 2015 (has links)
This diploma thesis deals with theme "Quality evaluation of gluten-free food, concretely gluten-free pastries". Theoretical part is concerned about coeliac disease in general, their symptoms, forms and diagnostic. There is described basic principal of coeliac disease and approachable gluten-free food. Then the basics of sensory analyse are described. Practical part is focused on finding suitable gluten-free flour and baking samples of bread based on recipe with care about improving nutritional value. Baked bread samples, made from commixture of gluten-free flour with enrichment of different amount of flaxseed, were evaluated with suitable methods of sensory analysis. This analyse shows which sample is the most preferred and based on those information it is proposed to enlarge offer in gluten-free pastry.
7

UTILIZAÇÃO DE FARINHA DE CHIA (Salvia hispânica) NA ELABORAÇÃO DE PÃO SEM GLÚTEN SEM ADIÇÃO DE GOMA E GORDURA / THE USE OF CHIA (hispanic Salvia) FLOUR ON PREPARATION OF GLUTEN FREE BREAD WITHOUT GUM AND FAT

Huerta, Katira da Mota 12 March 2015 (has links)
Celiac disease is a permanent intolerance to gluten and its treatment is based in the total removal of these dietary proteins . The chia seed is highly nutritious because of the high content of protein, dietary fiber and essential fatty acids. In presence of water the seed exudes a transparent mucilaginous gel that has emulsifying properties, becoming it an excellent ingredient for use as a substitute for fats and starches in the baking industry. This work aimed to evaluate the effect chia flour (Salvia Hispanic L.) in the physical, microbiological, nutritional and sensory gluten-free breads prepared without addition of starch and fat. Chemical composition analysis were carried out at the flour and developed products. To determine the quality of the bread was developed analyzes of specific volume, mass rearing, cooking losses , water activity , texture, crust color and crumb . The count of yeasts and molds was held for five days of storage and the acceptability and purchase intent of the bread was evaluated by an affective test with 50 untrained volunteers. The chemical composition of the bread indicates that the presence of chia flour increases the nutritional value and provides the decrease in carbohydrate content . All the texture parameters were influenced by partial replacement of rice and soybean flour by chia flour. Also the color of the bread became darker and decreased the specific volume and the losses caused during cooking. Regarding sensory analysis, for bread prepared without gum , the formulation containing 2.5% of chia in replacement of rice and soy flour was the most accepted with values close to 5 score on the scale represented by " liked ". On the other hand, for bread prepared without fat all the treatments showed no significant difference for flavor and texture from the standard sample. Also, the treatment with 2.5% of chia flour showed purchase intention similar to the standard for both cases . The addition of chia flour on gluten-free breads without gum and fat resulted in a healthy food product alternative for celiac consumer. However we suggest more studies to improve the bread texture parameters. / A doença celíaca é uma intolerância permanente ao glúten e seu tratamento consiste basicamente na remoção total dessas proteínas da dieta. A chia é um grão altamente nutritivo devido ao seu elevado conteúdo de proteínas, fibra alimentar e ácidos graxos essenciais, em presença de água, ela exsuda um gel transparente mucilaginoso que possui propriedades emulsificantes, isso a torna um excelente ingrediente para ser utilizado como substituto de gorduras e gomas na indústria da panificação. Este trabalho teve como objetivo avaliar o efeito da farinha de chia (Salvia hispânica L.) na qualidade física, microbiológica, nutricional e sensorial de pães sem glúten elaborados sem adição de goma e gordura. Foram realizadas análises de composição química nas farinhas e nos produtos desenvolvidos. Para determinar a qualidade dos pães, foram desenvolvidas análises de volume específico, elevação da massa, perdas por cocção, atividade de água, textura, cor da crosta e miolo. A contagem de bolores e leveduras foi realizada durante cinco dias de estocagem e a aceitabilidade e intenção de compra dos pães foi avaliada através de um teste afetivo com 50 provadores não treinados. A composição centesimal dos pães indica que a farinha de chia quando adicionada a formulação aumenta o valor nutricional e diminui o teor de carboidratos. Todos os parâmetros de textura foram influenciados com a substituição parcial das farinhas de arroz e soja por farinha de chia, a cor dos pães tornou-se mais escura e houve diminuição do volume específico e das perdas ocasionadas durante a cocção. Com relação a análise sensorial, para os pães elaborados sem goma, a formulação que continha 2,5% de farinha de chia em substituição as farinhas de arroz e soja foi a mais aceita com valores próximos a 5, escore representado na escala por gostei , já para os pães elaborados sem gordura todos os tratamentos não apresentaram diferença significativa para sabor e textura com relação ao padrão. O tratamento com 2,5% de farinha de chia apresentou intenção de compra semelhante ao padrão para ambos os casos. A adição de farinha de chia na elaboração de pães sem glúten sem goma e gordura resultou em um produto que pode ser uma alternativa de alimento saudável para o consumidor celíaco, porém sugerem-se mais estudos que busquem a melhoria dos parâmetros de textura dos pães.
8

Desenvolvimento de pão sem glúten com farinha de arroz e de batata-doce / Development of gluten-free bread with rice and sweet potato flour

Franco, Vilmara Araújo 30 September 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-28T10:26:08Z No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-28T10:27:53Z (GMT) No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-01-28T10:27:53Z (GMT). No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-09-30 / Celiac disease (CD) is a permanent intolerance to gluten, characterized by atrophy of the small intestine and consequent malabsorption of nutrients. Treatment of DC consists in the introduction gluten free diet permanently. The gluten-free bread is the product that celiac would like to find more easily in the market, allowing wider distribution of products with low cost, and convenience. This research aimed to characterize the flours of rice and sweet potatoes flour, formulate gluten-free bread for celiacs, applying different hydrocolloids (carboxymethyl cellulose and xanthan gum) and verify the effect of substitution of rice flour (RF) for sweet potatoes flour (SPF) on technological and sensory quality of bread. First, it determined the chemical composition of flour performing moisture analysis, water activity, acidity, pH, lipids, protein, ash, dietary fiber, carbohydrates, amylose content, grain size and color. Were also made microbiological analysis (Salmonella sp., Bacillus cereus, coliforms, molds and yeasts). Starch paste property was determined for RF, and their mixtures (25% and 75% RF, 50% and 50% RF, 75% SPF and 25% RF). At the second stage, the processing of breads occurred using the hydrocolloids carboxymethylcellulose (CMC) and xanthan gum (XG) in a farinaceous-based rice flour to develop gluten-free bread. Then, it was found the best results in respect to texture (hardness, elasticity, cohesiveness and chewiness), color (of the crust and crumb) and specific volume. Thus, it was held the replacement of rice flour by sweet potato flour and assessed their effects on textural parameters, color and specific volume, such as the acceptability of using sweet potatoes flour in bread formulation without gluten. For the production of bread were used rice flour (100%), granulated sugar (12%), water (150%), albumin (10%), margarine (10%), dried yeast (6%), salt (2%) and different concentrations of CMC and XG (in the values of 0%, 0,5%, 1,0%, 1,5% and 2%). The data were submitted to analysis of variance (ANOVA) and the averages compared by Tukey test (p ˂ 0,05). Yet, it was held microbiological analysis of the loaves and ordering preference test with consumers of bread. Flours differed significantly (p <0,05) according to L*, a* and b* color coordinates. The sweet potato flour presented itself darker than the rice one. In the characterization were obtained the following standards: sweet potatoes flour (moisture 9,18%, 9,92% protein, lipid 1,72%, 1,51% ash, 3,77% fiber and carbohydrates 77,81 %) and rice flour (13,31% moisture, 10,34% protein, 1,41% lipid, ash 0,31%, fiber 0,76%, carbohydrates 75,03%). In the assessment of paste properties of the flours and their mixtures, it was observed that RF paste temperature (88,65°C) was superior compared to the other samples. The maximum viscosity decreased with the increase of SPF in the blend. The values of final viscosity and retrogradation tendency decreased as increased SPF content in the mix. The paste properties of the mixtures of RF and SPF should be seen in a joint manner because they affect the texture in gluten-free breads. In gluten-free bread with rice flour processing it was discovered that for all the analyzes the control sample (without hydrocolloid) differed significantly (p <0,05) of others. It was found that with the use of 2% of CMC, there was obtained best results in relation to the set of analyzes, and sensorially there was no significant difference (p <0,05) between samples containing hydrocolloids. With the use of hydrocolloid CMC and replacement of RF for SPF, it was found that the higher the ratio of SPF, the lower the specific volume and the higher the hardness of the samples. However, the sample with 25% SPF was not significantly different compared to control hardness, chewiness, 10 cohesiveness and elasticity sample. The addition of SPF in the breads gave a darker color to the samples. The microbiological evaluation of the sample with 25% SPF resulted in a bread with a shelf life of 07 days. This same sample achieved a 80,3% acceptance rate, considered high for being a new product developed,. The analysis of only 2% purchase intent of tasters certainly would not buy the product, showing that the use of hydrocolloids combined with the use of sweet potato flour in gluten-free bread formulations, is an option for celiac public to obtain Products with sensorial quality. / A doença celíaca (DC) é uma intolerância permanente ao glúten, caracterizada por atrofia da mucosa do intestino delgado e consequente má absorção de nutrientes. O tratamento da DC consiste na introdução de dieta sem glúten de forma permanente. O pão sem glúten é o produto que os celíacos gostariam de encontrar com maior facilidade no mercado permitindo ampla distribuição dos produtos com baixo custo, além da praticidade. Esta pesquisa teve como objetivo caracterizar as farinhas de arroz e de batata-doce, elaborar pão isento de glúten para doentes celíacos, aplicando diferentes hidrocolóides (carboximetilcelulose e goma xantana) e verificar o efeito da substituição da farinha de arroz (FA) por farinha de batatadoce (FBD) na qualidade tecnológica e sensorial dos pães. Primeiramente, determinou-se a composição centesimal das farinhas realizando análises de umidade, atividade de água, acidez, pH, proteínas, lipídios, cinzas, fibra alimentar, carboidratos, teor de amilose, granulometria e cor; além das análises microbiológicas (Salmonela sp., Bacillus cereus, coliformes, bolores e leveduras). A propriedade de pasta do amido foi determinada para FA, FBD e suas mesclas (25% FBD e 75% FA; 50% FBD e 50% FA; 75% FBD e 25% FA). Na segunda etapa, ocorreu o processamento dos pães utilizando os hidrocolóides carboximetilcelulose (CMC) e goma xantana (GX) em base farinácea de farinha de arroz para desenvolvimento de pão sem glúten, em seguida, verificou-se o melhor resultado em relação à textura (dureza, elasticidade, coesividade e mastigabilidade), cor (da crosta e do miolo) e volume específico, com isso, realizou-se a substituição da farinha de arroz pela farinha de batata-doce e analisou os seus efeitos sobre os parâmetros texturais, cor e volume específico, tal como, a aceitabilidade do uso da farinha de batata-doce em formulação de pão sem glúten. Para a fabricação dos pães foram usados farinha de arroz (100%), açúcar cristal (12%), água (150%), albumina (10%), margarina (10%), fermento biológico seco (6%), sal (2%) e diferentes concentrações de CMC e GX (nos valores de 0%, 0,5%, 1,0%, 1,5% e 2%). Os dados foram submetidos a análise de variância (ANOVA) e as médias comparadas pelo teste de Tukey (p ˂ 0,05). Ainda, realizou-se análise microbiológica dos pães e teste de preferência por ordenação com consumidores de pães. As farinhas diferiram significativamente (p<0,05) em relação às coordenadas L*, a* e b* de cor, onde a farinha de batata-doce apresentou-se mais escura que a de arroz. Na caracterização obtiveram-se os seguintes padrões: farinha de batata-doce (umidade 9,18%, proteína 9,92%, lipídio 1,72%, cinzas 1,51%, fibras alimentares 3,77% e carboidratos 77,81%) e farinha de arroz (umidade 13,31%, proteína 10,34%, lipídio 1,41%, cinzas 0,31%, fibras alimentares 0,76%, carboidratos 75,03%). Na avaliação das propriedades de pasta das farinhas e de suas mesclas, observou-se que a temperatura de pasta de FA (88,65°C) foi superior em relação às demais amostras. A viscosidade máxima diminuiu com o aumento de FBD na mescla. Os valores de viscosidade final e de tendência à retrogradação diminuíram à medida que aumentou o teor de FBD na mescla. As propriedades de pasta das mesclas de FA com FBD devem ser vistas de forma conjunta, pois afetam a textura em pães sem glúten. No processamento de pão sem glúten com farinha de arroz detectou-se que para todas as análises a amostra controle (sem hidrocolóide) diferiu significativamente (p<0,05) das demais. Observou-se que com o uso de 2% de CMC obtevese o melhor resultado em relação ao conjunto de análises, e sensorialmente não foi detectada diferença significativa (p<0,05) entre as amostras contendo hidrocolóides. Com o uso do hidrocolóide CMC e a substituição de FA por FBD, detectou-se que quanto maior a proporção de FBD, menor foi o volume específico e maior a dureza das amostras. No entanto, a amostra com 25% de FBD não diferiu significativamente em relação ao controle na dureza, mastigabilidade, coesividade e elasticidade da amostra. A incorporação de FBD nos pães 8 conferiu uma cor mais escura às amostras. A avaliação microbiológica da amostra com 25% de FBD resultou em um pão com vida útil de 07 dias. Esta mesma amostra obteve um índice de aceitabilidade de 80,3%, sendo considerado alto por ser um novo produto desenvolvido, onde na análise de intenção de compra apenas 2% dos provadores certamente não comprariam o produto. Mostrando que o uso de hidrocolóides e a adição de farinha de batata-doce a formulações de pão sem glúten, é uma opção para o público celíaco obter produtos com qualidade sensorial.
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Otimização de propriedades nutricionais e sensoriais de produtos à base de amaranto enriquecidos com frutanos, para intervenção em celíacos / Nutritional and sensory optimization of amaranth based products enriched with fructans, for nutritional intervention in celiac

Vanessa Dias Capriles 17 December 2009 (has links)
Introdução: A doença celíaca não tem cura e apresenta como único tratamento a dieta isenta de glúten. Frequentemente observa-se a má absorção de cálcio em celíacos, consequência dos menores níveis de transportadores de cálcio no enterócito desses indivíduos. Os celíacos têm dificuldade em dar sequência ao tratamento dietético devido à escassez de produtos isentos de glúten, tornando fundamental o desenvolvimento de produtos para esta população. Isso pode ser feito por meio do uso de matérias primas isentas de glúten e com valor nutritivo agregado, como o grão de amaranto, e de ingredientes que contribuem para o aumento da absorção de cálcio através de absorção passiva nos colonócitos, como os frutanos inulina e oligofrutose. Objetivo: Desenvolver e otimizar as propriedades nutricionais e sensoriais de produtos à base de amaranto enriquecidos com frutanos, para intervenção nutricional em celíacos. Metodologia: Foram elaborados snacks à base de milho e amaranto (50, 75 e 100%), barras e pães sem glúten, enriquecidos com 4 gramas de frutanos/ porção. Para maximizar a aceitabilidade das barras foi utilizado um planejamento experimental para misturas de amaranto extrusado, estourado e laminado. Para maximizar o valor nutritrivo e a aceitabilidade do pão sem glúten foi utilizado o planejamento experimental para misturas de farinha de arroz, fécula de batata e farinha de amaranto. Os produtos foram caracterizados quanto a composição centesimal, o índice glicêmico (IG) e a carga glicêmica (CG). Também foram avaliadas as propriedades físicas e a aceitabilidade (escala hedônica estruturada de nove pontos) durante o período de armazenamento. Resultados e discussão: Os snacks foram aceitos e apresentaram estabilidade de suas características físicas e da aceitabilidade durante os 135 dias de armazenamento. O efeito combinado do amaranto e dos frutanos gerou redução de 19% do IG e de 56% da CG dos snacks. O amaranto estourado e laminado apresentaram interações sinérgicas para a aceitabilidade das barras (R2(aj)>92%, p=0,00). A formulação à base de amaranto estourado e laminado (½,½) foi diversificada em seis diferentes sabores e apresentou estabilidade de suas propriedades físicas e da aceitabilidade durante os seis meses de armazenamento. A estimativa da resposta glicêmica revelou IG moderado e CG baixa das barras. Pães com 33 e 45% de farinha de amaranto apresentaram destacado valor nutritivo e aceitabilidade. A incorporação de amaranto e de frutanos ocasionou redução de 20% do IG e de até 53% da CG do pão sem glúten. Conclusão: Os produtos desenvolvidos (snacks, barras e pães sem glúten) apresentaram destacado valor nutritivo em relação aos produtos convencionais, atenuação da resposta glicêmica e alta aceitabilidade pelo consumidor, podendo contribuir para uma maior variação e adequação da dieta dos celíacos e também para auxiliar no aumento da absorção de cálcio / Introduction: Celiac disease does not have a cure and the only scientifically proven treatment is strict lifelong adherence to a gluten-free diet. Calcium malabsorption is frequently found in celiac, possibly due to negligible amounts of calcium-binding protein in their enterocytes. Compliance with dietary treatment is often difficult due to the lack of gluten-free products, so it is essential to develop specific products for this population. This can be done through the use of gluten-free raw materials of great nutritional value, such as amaranth grain, and ingredients that contribute to the calcium absorption increasement through passive absorption in colonocytes, such as the fructans inulin and oligofructose. Objective: Develop and optimize the nutritional and sensory properties of amaranth based products enriched with fructans, for nutritional intervention in celiac. Methods: Snacks from blends of corn and amaranth (50, 75 and 100%), amaranth bars and gluten-free bread, all enriched with 4 grams of fructans/ portion, were prepared. A mixture experiment of extruded, popped and flaked amaranth was used to optimize the sensory acceptability of the bars. A mixture experiment of rice flour, potato starch and amaranth flour was used to maximize the nutritional value and sensory acceptability of gluten-free bread. Products chemical composition, glycemic index (GI) and glycemic load (GL), were evaluated. The physical properties and sensory acceptability (nine point hedonic scale) were assessed during the storage time. Results and discussion: Snacks were sensory accepted and maintained their physical characteristics and sensory acceptability during the 135 days of storage. The combined effect of amaranth and fructans resulted in 19% reduction of GI and 56% of GL of snacks. Popped and flaked amaranth present synergistic interactions to sensory acceptability of the bars (R2(adj)>92%, p=0,00). Bars were produced with popped and flaked amaranth (½,½) in six different flavors and its physical properties and sensory acceptability were stable during the six months of storage. The predicted glycemic response showed moderate GI and low GL bars. Breads with 33 and 45% of amaranth flour had higher nutritional value and sensory acceptability. Amaranth and fructans addition led to a reduction of approximately 20% of GI and up to 53% of the GL of gluten-free breads. Conclusion: The developed products (snacks, bars and gluten-free breads) had superior nutritional composition than conventional products, reduced glycemic response, high consumer sensory acceptability, great potential to contribute to variation and adequacy of celiac diet and also help to increase calcium absorption.
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Uticaj prehrambenih vlakana šećerne repe i jabuke na reološke parametre testa i kvalitet bezglutenskog hleba / Influence of sugar beet and apple dietary fibres on batter rheology and gluten free bread quality

Đorđević Marijana 25 September 2020 (has links)
<p>Sagledavajući značaj nutritivne vrednosti bezglutenskog hleba u prevenciji dodatnih zdravstvenih poremećaja kod obolelih od celijakije, kao i prisutnog trenda bezglutenske ishrane, u okviru ove disertacije analizirana je mogućnost obogaćenja bezglutenskog hleba prehrambenim vlaknima. Ispitan je uticaj različite vrste i količine (3, 5, 7%) prehrambenih vlakana (vlakna &scaron;ećerne repe i vlakna jabuke), količine hidroksipropil metil celuloze - HPMC (2, 3, 4%) i količine vode (180&ndash;230%) na reolo&scaron;ke osobine bezglutenskog testa (svojstva proticanja i viskoelastične osobine), kvalitet i nutritivnu vrednost bezglutenskog hleba. Rezultati ove disertacije ukazuju da dodatak vlakana &scaron;ećerne repe i jabuke ne umanjuje pozitivan uticaj HPMC na reolo&scaron;ke osobine bezglutenskog testa, formiranje i ojačavanje njegove strukture. Bezglutenski hleb privlačne boje, veće zapremine, manje tvrdoće sredine i odličnih senzorskih karakteristika dobijen je kod uzoraka sa 4% HPMC, 3, 5 ili 7% vlakana &scaron;ećerne repe/jabuke i 220%/190% vode. Sadržaj ukupnih prehrambenih vlakana kod uzoraka sa 3% vlakana je iznad 4,5 g/100 g, a kod uzoraka sa 7% vlakana čak oko 6 g/100 g bezglutenskog hleba. Postignut sadržaj ukupnih prehrambenih vlakana je iznad propisane vrednosti za proizvode koji mogu biti nosioci nutritivne izjave &bdquo;izvor vlakana&ldquo;, čime je ostvaren cilj ove disertacije.</p> / <p>Considering the importance of the gluten-free bread nutritional value in the prevention of additional health disorders in patients with celiac disease, as well as the arising gluten-free diet trend, the possibility of enriching gluten-free bread with dietary fibers was analyzed within this dissertation. The influence of different types and amounts (3, 5, 7%) of dietary fibers (sugar beet and apple fibers), the amount of hydroxypropylmethylcellulose - HPMC (2, 3, 4%) and the amount of water (180&ndash;230%) on rheological properties of gluten-free batter (flow and viscoelastic properties), quality and nutritional value of gluten-free bread. The results of this dissertation indicate that the addition of sugar beet and apple fibers does not diminish the positive influence of HPMC on the rheological properties of the gluten-free batter, the formation and strengthening of its structure. Gluten-free bread with appealing color, higher volume, lower hardness and excellent sensory characteristics was obtained in samples with 4% HPMC, 3, 5 or 7% sugar beet/apple fibers and 220%/190% water. The total dietary fibers content in samples with 3% fibers is above 4.5 g/100 g, and in samples with 7% fibers approximately 6 g/100 g of gluten-free bread. The accomplished total dietary fibers content is above the prescribed value for products that may bear the nutritional statement &quot;source of fiber&quot;, thus achieving the goal of this dissertation.</p>

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