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Authors
Abstract(s)
O trigo espelta, chamado trigo ancestral, possui um perfil nutricional interessante devido ao alto teor de proteínas, aminoácidos essenciais e vitaminas. A composição nutricional desse grão tem sido associada a efeitos benéficos à saúde, e, com isso, estudos têm sido voltados à utilização da farinha de trigo espelta em diversos produtos de panificação. Assim, o objetivo geral deste trabalho foi avaliar o efeito da substituição parcial de farinha de trigo por farinha de trigo espelta na qualidade tecnológica do pão e na sua vida de prateleira, bem como a possível utilização de melhoradores para aprimorar a sua qualidade final. Estes objetivos foram atingidos por meio de três experiências que visaram: (i) entender os efeitos da substituição parcial por farinha espelta (0, 5, 10, 15%), do tipo de farinha de trigo (T65, T55 e T150) e do nível de adição de água (55,0, 57,5, 60,0 e 62,5%) na reologia da massa; (ii) avaliar a qualidade tecnológica do pão composto (0, 10, 20, 30, 100%) e a sua deterioração durante o tempo de prateleira; e (iii) otimizar uma formulação fortificada com glúten (9%) e ácido ascórbico (0,50%) mediante o uso de dois melhoradores, fosfolipase (0,10, 0,30 e 0,50%) e glicose oxidase (0,02, 0,06 e 0,10%), com a finalidade de aperfeiçoar as características tecnológicas dos pães de farinha espelta.
A massa foi caracterizada quanto as propriedades reológicas de adesividade com a célula SMS/Chen-Hoseney, e extensibilidade com o acessório Kieffer; a qualidade tecnológica do pão foi avaliada por volume específico, atividade de água, perdas por cocção, análise do perfil de textura e análise de imagem da distribuição alveolar do miolo; e os indicadores de deterioração do pão foram avaliados mediante atividade da água, dureza, coesividade e resiliência do miolo ao longo de 5 dias de armazenamento. Toda a análise estatística foi realizada no programa estatístico R, e consistiu no ajuste de análises de variância para testar efeitos principais e interações, seguido de provas de comparação de médias Tukey (α=0,05).
Neste trabalho, verificou-se que os níveis de adição de água, nível de farinha de espelta e tipo de farinha de trigo causaram mudanças significativas (p<0,05) nas propriedades reológicas das 48 formulações de massas. Observou-se que os níveis de 5% e 10% de farinha de espelta em farinha de trigo T55 não apresentaram diferenças significativas nas propriedades de resistência à extensão e extensibilidade; em contra partida, para as farinhas T65 e T150, ocorreu uma redução significativa da resistência à extensão (p<0,05). Mais ainda, as formulações com substituições parciais realizadas na farinha T55 apresentaram-se mais extensíveis. Por estas razões, a farinha de trigo T55 foi a escolhida para a elaboração de pães compostos.
Os maiores níveis de substituição de farinha T55 por farinha de espelta causaram uma diminuição (p<0,05) no volume e um aumento (p<0,05) da dureza dos pães; contudo, entre os níveis de 20% e 30%, o miolo dos pães compostos não apresentou diferenças (p>0,05) nos atributos de resiliência, elasticidade, coesividade e mastigabilidade. Todavia, o mais alto nível de substituição por farinha de espelta (30%) produziu um miolo mais apelativo, de maior uniformidade alveolar (p<0,05) e menor tamanho de alvéolo (p<0,05). Durante o tempo de prateleira, observou-se que todos os níveis de substituição diferiram da amostra controle (p<0,05). A dureza aumentou progressivamente em cada um dos tratamentos com os dias de armazenamento (p<0,01); entretanto, os pães de 20% e 30% de farinha espelta não apresentaram diferenças mínimas significativas (p<0,05) entre eles. O fato das amostras com 20% e 30% não diferirem estatisticamente para a maioria dos parâmetros, permitiu a escolha da mistura de 70% de farinha de trigo T55 e 30% de farinha de espelta para dar continuidade ao experimento.
As enzimas glicose oxidase e fosfolipase alteraram a reologia da massa: verificou-se que as doses de 0,02% a 0,06% para glicose oxidase e 0,30% e 0,50% para a fosfolipase aumentaram (p<0,05) a extensibilidade das massas substituídas. O volume dos pães decaiu (p<0,05) com o aumento da dose de glicose oxidase, enquanto maiores doses de fosfolipase causaram um aumento (p<0,05) deste importante atributo de qualidade. As doses de 0,02% de glicose oxidase e 0,50% de fosfolipase produziram as maiores médias (p<0,05) de volume específico dentre todas as concentrações testadas. Para as propriedades texturiais, todos os tratamentos testados causaram melhora nos parâmetros avaliados; contudo, as doses de 0,30% fosfolipase e 0,06% glicose oxidase ocasionaram um aumento (p<0,05) da dureza e mastigabilidade. Com doses de 0,02% glicose oxidase e 0,50% fosfolipase obtiveram-se as melhores médias para os parâmetros avaliados e, por esta razão, consideram-se como as concentrações ótimas para melhorar a qualidade das propriedades tecnológicas dos pães substituídos com 30% de farinha de espelta.
Spelt wheat, also known as ancestral wheat, has an interesting nutritional profile due to its high content of proteins, essential amino acids and vitamins. The nutritional composition of this grain has been associated with beneficial health effects; and hence, studies have been focused on the use of spelt wheat flour in various bakery products. Thus, the general objective of this work was to evaluate the effect of the partial replacement of wheat flour with spelt wheat flour on the technological quality of bread and on its shelf life, as well as the possible use of enzymatic improvers to enhance its final quality. These objectives were achieved through three experiments aimed at: (i) understanding the effects of partial replacement with spelt flour (0, 5, 10, 15%), type of wheat flour (T65, T55 and T150) and level of water addition (55.0, 57.5, 60.0 and 62.5%) on the rheology of the composite dough; (ii) evaluating the technological quality of composite bread (0, 10, 20, 30, 100%), and its deterioration during shelf life; and (iii) optimising a formulation fortified with gluten (9%) and ascorbic acid (0.50%) using two enzymatic enhancers, phospholipase (0.10, 0.30 and 0.50%) and glucose oxidase (0.02, 0.06 and 0.10%), in order to improve the technological characteristics of spelt flour breads. The dough was characterised in terms of the rheological properties of stickiness using the SMS/Chen-Hoseney cell, and extensibility using the Kieffer accessory; the technological quality of the bread was evaluated by volume, water activity, cooking loss, texture profile analysis, and bread crumb grain image analysis; and the indicators of bread deterioration through crumb water activity, hardness, cohesiveness and resilience over 5 days of storage. All statistical analyses were performed in the free programme R, and consisted of adjusting analysis of variance to test main effects and interactions, followed by Tukey’s comparison of means (α = 0.05). In the first experiment, it was found that the levels of water addition, spelt flour level and wheat flour type caused significant changes (p<0.05) in the rheological properties of the 48 dough formulations. Formulations with partial substitutions made in wheat flour T55 were overall more resistant and extensible. The substitution levels of 5% and 10% of T55 with spelt flour did not present a significant reduction in the properties of resistance to extension and extensibility; by contrast for the base flours T65 and T150 there was a significant reduction in the resistance to extension (p<0.05). For this reason, wheat flour T55 was chosen for the preparation of the composite breads. The higher levels of substitution of T55 wheat flour with spelt flour caused a decrease (p <0.05) in specific volume and an increase (p <0.05) in bread crumb hardness; however, between the levels of 20% and 30%, the bread crumbs showed no differences (p>0.05) in the attributes of resilience, elasticity, cohesiveness and chewiness. However, the highest level of substitution by spelt flour (30%) produced crumbs of greater alveolar uniformity (p<0.05) and smaller alveolar size (p<0.05). During shelf life, it was observed that all levels of substitution differed statistically from the control sample. Crumb hardness increased progressively in each treatment with days of storage (p<0.01); however, there were no minimum significant differences (p<0.05) between the 20% and 30% substitution levels. The fact that the samples with 20% and 30% did not differ statistically for most of the quality parameters, allowed the choice of a mixture of 70% wheat flour T55 and 30% spelt flour to carry on with this experiment. The enzymes glucose oxidase and phospholipase modified dough rheology: it was found that doses between 0.02% to 0.06% glucose oxidase and doses between 0.30% to 0.50% phospholipase increase (p<0.05) the extensibility of the composite doughs. The specific volume of the bread loaves declined (p<0.05) with higher doses of glucose oxidase, while the higher doses of phospholipase caused an increase (p<0.05) in loaf volume. The concentrations of 0.02% glucose oxidase and 0.50% phospholipase rendered the highest means (p<0.05) of specific volume among all tested concentrations. For textural properties, all treatments caused an improvement in the parameters evaluated; however, the concentrations of 0.30% phospholipase and 0.06% glucose oxidase caused a significant increase (p<0.05) in hardness and chewiness. Using doses of 0.02% glucose oxidase and 0.50% phospholipase, the best values were obtained for most of the quality parameters and, for this reason, this is the most suitable enzymatic improvers combination to enhance the technological quality properties of breads replaced with 30% of spelt flour.
Spelt wheat, also known as ancestral wheat, has an interesting nutritional profile due to its high content of proteins, essential amino acids and vitamins. The nutritional composition of this grain has been associated with beneficial health effects; and hence, studies have been focused on the use of spelt wheat flour in various bakery products. Thus, the general objective of this work was to evaluate the effect of the partial replacement of wheat flour with spelt wheat flour on the technological quality of bread and on its shelf life, as well as the possible use of enzymatic improvers to enhance its final quality. These objectives were achieved through three experiments aimed at: (i) understanding the effects of partial replacement with spelt flour (0, 5, 10, 15%), type of wheat flour (T65, T55 and T150) and level of water addition (55.0, 57.5, 60.0 and 62.5%) on the rheology of the composite dough; (ii) evaluating the technological quality of composite bread (0, 10, 20, 30, 100%), and its deterioration during shelf life; and (iii) optimising a formulation fortified with gluten (9%) and ascorbic acid (0.50%) using two enzymatic enhancers, phospholipase (0.10, 0.30 and 0.50%) and glucose oxidase (0.02, 0.06 and 0.10%), in order to improve the technological characteristics of spelt flour breads. The dough was characterised in terms of the rheological properties of stickiness using the SMS/Chen-Hoseney cell, and extensibility using the Kieffer accessory; the technological quality of the bread was evaluated by volume, water activity, cooking loss, texture profile analysis, and bread crumb grain image analysis; and the indicators of bread deterioration through crumb water activity, hardness, cohesiveness and resilience over 5 days of storage. All statistical analyses were performed in the free programme R, and consisted of adjusting analysis of variance to test main effects and interactions, followed by Tukey’s comparison of means (α = 0.05). In the first experiment, it was found that the levels of water addition, spelt flour level and wheat flour type caused significant changes (p<0.05) in the rheological properties of the 48 dough formulations. Formulations with partial substitutions made in wheat flour T55 were overall more resistant and extensible. The substitution levels of 5% and 10% of T55 with spelt flour did not present a significant reduction in the properties of resistance to extension and extensibility; by contrast for the base flours T65 and T150 there was a significant reduction in the resistance to extension (p<0.05). For this reason, wheat flour T55 was chosen for the preparation of the composite breads. The higher levels of substitution of T55 wheat flour with spelt flour caused a decrease (p <0.05) in specific volume and an increase (p <0.05) in bread crumb hardness; however, between the levels of 20% and 30%, the bread crumbs showed no differences (p>0.05) in the attributes of resilience, elasticity, cohesiveness and chewiness. However, the highest level of substitution by spelt flour (30%) produced crumbs of greater alveolar uniformity (p<0.05) and smaller alveolar size (p<0.05). During shelf life, it was observed that all levels of substitution differed statistically from the control sample. Crumb hardness increased progressively in each treatment with days of storage (p<0.01); however, there were no minimum significant differences (p<0.05) between the 20% and 30% substitution levels. The fact that the samples with 20% and 30% did not differ statistically for most of the quality parameters, allowed the choice of a mixture of 70% wheat flour T55 and 30% spelt flour to carry on with this experiment. The enzymes glucose oxidase and phospholipase modified dough rheology: it was found that doses between 0.02% to 0.06% glucose oxidase and doses between 0.30% to 0.50% phospholipase increase (p<0.05) the extensibility of the composite doughs. The specific volume of the bread loaves declined (p<0.05) with higher doses of glucose oxidase, while the higher doses of phospholipase caused an increase (p<0.05) in loaf volume. The concentrations of 0.02% glucose oxidase and 0.50% phospholipase rendered the highest means (p<0.05) of specific volume among all tested concentrations. For textural properties, all treatments caused an improvement in the parameters evaluated; however, the concentrations of 0.30% phospholipase and 0.06% glucose oxidase caused a significant increase (p<0.05) in hardness and chewiness. Using doses of 0.02% glucose oxidase and 0.50% phospholipase, the best values were obtained for most of the quality parameters and, for this reason, this is the most suitable enzymatic improvers combination to enhance the technological quality properties of breads replaced with 30% of spelt flour.
Description
Mestrado de dupla diplomação com o Centro Federal de Educação Tecnológica Celso Suckow da Fonseca - CEFET/RJ
Keywords
Espelta Panificação Massas Análise de perfil de textura Melhoradores