Detalhes bibliográficos
| Ano de defesa: |
2019 |
| Autor(a) principal: |
Moreno, Raquel Troncoso Chaves
 |
| Orientador(a): |
Caliari, Márcio
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| Banca de defesa: |
Caliari, Márcio,
Ferreira, Tânia Aparecida Pinto de Castro,
Ribeiro, Alline Emannuele Chaves,
Oliveira, Érica Resende de,
Sousa, Gardênia Martins de |
| Tipo de documento: |
Dissertação
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| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de Goiás
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| Programa de Pós-Graduação: |
Programa de Pós-graduação em Ciência e Tecnologia de Alimentos (EA)
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| Departamento: |
Escola de Agronomia - EA (RG)
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| País: |
Brasil
|
| Palavras-chave em Português: |
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| Palavras-chave em Inglês: |
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| Área do conhecimento CNPq: |
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| Link de acesso: |
http://repositorio.bc.ufg.br/tede/handle/tede/11051
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Resumo: |
The objective of this work was to develop and characterize the chemical, physical and physicochemical properties of gluten-free breads prepared from the mixture of flour from broken rice grains (FA), chickpea flour (FGB), potato starch (FB) and cassava starch (FM), added with different proportions of enzymatic extract of alpha amylase, amyloglucosidase and cellulase. The flours and starches used in the research were characterized as to their physical, chemical and technological properties. To define the ideal concentration of each of the flour and starch in the mixture, two experimental designs were carried out, the first one being a completely randomized design (DIC), in which the best proportion of FGB in the formulation was defined, and the second the mixtures , in which the ideal proportions for FA, FM and FB were defined in the treatments. The loaves were analyzed for specific volume, texture parameters and instrumental parameters of color. Also, enzymatic extracts of alpha amylase and amyloglucosidase and cellulase were produced, and the enzymatic activity for each enzyme was defined. Breads with different concentrations of enzymatic extracts were prepared and evaluated according to the specific volume, texture parameters, color instrumental parameters, moisture content and water activity, where the ideal formulation was physicochemical characterization. Chickpea flour had higher fiber, protein, lipid and ash content. For the amylose content, the values of 19.77 g 100-1 were found for chickpea flour, 26.83 g 100-1 for rice flour, 28.36 g 100-1 for cassava starch and 29.60 g 100-1 for potato starch. In relation to the technological properties, rice flour had a higher retrogradation value (337 RVU), and cassava and potato starch had the highest viscosity drop values (367 RVU and 1285 RVU, respectively) and maximum viscosity (514.58 RVU and 1447.71 RVU, respectively). According to the DIC, bread formulated with 35 g 100g-1 of FGB had a higher specific volume (2.96 cm3 g-1) and a hardness value of 12.55 N, and therefore was selected as being ideal. According to the design of the mixtures, the formulation with 50 g 100g-1 of FM, 25 g 100g-1 of FA and 25g 100g-1 of FB presented a higher specific volume (3 cm3 g-1), being then selected as ideal. The enzymatic extracts produced enzymatic activity of 2.68 U mL-1, 4.53 U mL-1 and 0.89 U mL-1 for alpha amylase, amyloglucosidase and cellulase, respectively. The formulation with the addition of 2 mL of the alpha amylase and amyloglucosidase enzyme extract presented significantly higher specific volume (3.26 cm3 g-1) and a significantly lower hardness value (4.72 N) than the other formulations and, therefore, was selected as the ideal. According to the physicochemical analysis, the addition of the enzyme extract reduced the value of available carbohydrates and total carbohydrates of the bread, but did not cause changes in fiber content, ashes, pH and titratable total acidity. From the results obtained for chickpea and rice flour and for manioc and potato starches it was possible to conclude that these are suitable for application in bakery products. The application of 2 mL of alpha amylase and amyloglucosidase enzymatic extract was able to significantly improve the specific volume and hardness values of the loaves, as well as to reduce the amount of available carbohydrates, demonstrating that the use of amylolytic enzymes may be an alternative feasible to improve the specific volume characteristics and texture parameters of gluten-free breads. |
