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Abstract(s)
A panificação é um processo industrial através do qual se realizam uma série de
operações ordenadas e sequenciais, que conduzem à obtenção de um produto final - o
pão. O Pão é um alimento fundamental para todas as classes sociais, tendo conseguido
uma posição transversal no comportamento alimentar da sociedade. Por isso a indústria
de panificação, alcançou uma posição de destaque a nível económico, visto ser, o pão,
um dos alimentos fundamentais da dieta diária humana.
Neste trabalho estudou-se o trigo panificável Barbela que constitui uma variedade
tradicional portuguesa antiga com boa produtividade em solos de baixa fertilidade em
ambientes com alta acidez, além de se adaptar a diferentes condições ambientais. O
objetivo foi desenvolver e caracterizar o pão produzido com farinha de trigo Barbela
T150, analisando as suas características microbiológicas, físico-químicas, químicas, e
atividade antimicrobiana.
A farinha de trigo Barbela apresentou teor de fenóis totais (7,57 ± 0,14 mg eq.
AG/g) e uma atividade antioxidante significativa (32,49 ± 0,57 mg eq. Trolox/g), o que
evidenciou o seu potencial como fonte de compostos bioativos. Em termos
microbiológicos, a farinha não apresentou contaminações, garantindo a sua conformidade
com os padrões de segurança alimentar. Nas análise físico-químicas, a farinha apresentou
um teor de humidade de 11,12%, o que está dentro dos limites regulamentares, e um teor
de cinzas de 1,58%, sugerindo riqueza em minerais. O conteúdo proteico foi de 12,65%,
o teor de glúten húmido foi 35,05% e o glúten seco de 13,13%. Estas características são
essenciais para a panificação, pois garantem a formação adequada de glúten.
Durante o processo de panificação, foram realizados ensaios para otimização das
condições de fermentação. Para tal aplicou-se o desenho de Plackett-Burmann efetuando
18 ensaios, usando 3 níveis de 4 fatores: tempo de fermentação (1h; 3h ;5h), temperatura
de fermentação (20°C; 30°C; 40°C), quantidade de sal (0,6; 1,0 e 4 g/L) e quantidade de
levedura (1,0; 3,0 e 4,0 g/L). Com base nos resultados do desenho experimental
selecionaram-se as seguintes condições ótimas para a preparação do pão: quantidade de
água 70g/L, quantidade de farinha 100 g, 1h de fermentação, temperatura 25°C, e 1g de
sal e levedura.
A massa fermentada ótima revelou resultados importantes, as análises físico-
químicas, obtiveram-se os resultados: teor de cinzas foi de 1,39%, indicando a quantidade
de material mineral presente na amostra, a proteína total 8,72%, um valor considerável para garantir a qualidade do glúten e a formação da estrutura adequada do pão. O pH da
massa foi de 6,9, essencial para a atividade enzimática e a produção de dióxido de carbono
durante a fermentação. Em termos de análises químicas, o teor de fenóis totais foi de 8,81
± 0,44 mg eq. AG/g, destacando a presença de compostos bioativos com propriedades
antioxidantes. Além disso, a atividade antioxidante, medida pelo ensaio de DPPH, atingiu
29,57 ± 0,65 mg eq. Trolox/g, reforçando o potencial antioxidante da massa fermentada.
As análises microbiológicas indicaram uma contagem total de leveduras de 6,48
± 0,04 log UFC/mL, o que reflete o desenvolvimento eficaz das leveduras, em particular
Saccharomyces cerevisiae, responsáveis pela produção de dióxido de carbono,
fundamental para a formação da rede de glúten. Estes resultados demonstram que a massa
fermentada ótima possui um perfil equilibrado de composição mineral, proteínas e
atividade antioxidante, o que contribui diretamente para a qualidade do pão final.
O teor de fenóis totais foi de 13,69 ± 0,26 mg eq de AG/ g por 100 g de pão,
indicando uma presença relevante de compostos fenólicos, conhecidos pelos seus
benefícios antioxidantes. Além disso, a capacidade antioxidante, medida através do
ensaio DPPH, apresentou um valor de 59,09 ± 2,00 mg eq de Trolox/g, evidenciando a
potencial.
Em termos físico-químicos, o pão apresentou um teor de humidade de 36,64%,
teor de cinzas de 1,69% e proteína total de 9,80%, teor de gordura 1,02%, um valor de
pH 5,98, teor em hidratos de carbono 50,84 g/100g e valor energético entre 251,82
Kcal/100g.Verificou-se uma atividade antimicrobiana significativa contra bactérias
Gram-positivas, como Staphylococcus aureus e Bacillus cereus, embora não tenha sido
verificada inibição contra Escherichia coli, sugerindo uma ação seletiva. No estudo do
tempo de vida de prateleira, observou-se ausência de microrganismos até ao T2. No
entanto, a partir do T4, registou-se um aumento progressivo na contagem de
microrganismos mesófilos totais, bem como de bolores e leveduras. Esta tendência
culminou numa degradação significativa ao T6, com a presença de Bacillus cereus.
Breadmaking is an industrial process involving a series of ordered and sequential operations that lead to the production of a final product—bread. Bread is a fundamental food for all social classes, having achieved a transversal position in the dietary behavior of society. For this reason, the baking industry has reached a prominent economic position, as bread is one of the staple foods of the human daily diet. In this study, the focus was on the bread wheat variety Barbela, a traditional Portuguese cultivar known for its good productivity in low-fertility soils in highly acidic environments and its adaptability to different environmental conditions. The aim was to develop and characterize bread made with Barbela wheat flour T150, analyzing its microbiological, physicochemical, chemical properties, and antimicrobial activity. Barbela wheat flour showed a total phenolic content of 7.57 ± 0.14 mg GAE/g and significant antioxidant activity (32.49 ± 0.57 mg Trolox equivalent/g), demonstrating its potential as a source of bioactive compounds. Microbiological analysis revealed no contamination, ensuring compliance with food safety standards. Regarding physicochemical analysis, the flour had a moisture content of 11.12%, within regulatory limits, and an ash content of 1.58%, indicating a richness in minerals. The protein content was 12.65%, with a wet gluten content of 35.05% and dry gluten of 13.13%. These characteristics are essential for breadmaking, ensuring the proper gluten formation. During the breadmaking process, experiments were conducted to optimize fermentation conditions. A Plackett-Burman design was applied with 18 trials, testing 4 factors at 3 levels: fermentation time (1h, 3h, 5h), fermentation temperature (20°C, 30°C, 40°C), salt content (0.6, 1.0, and 4 g/L), and yeast content (1.0, 3.0, and 4.0 g/L). Based on the experimental results, the following optimal conditions were selected for bread preparation: 70 g/L of water, 100 g of flour, 1h fermentation at 25°C, and 1 g of salt and yeast. The optimized fermented dough yielded important results. Physicochemical analysis showed an ash content of 1.39%, indicating the mineral content of the sample, and a total protein content of 8.72%, a significant value to ensure gluten quality and proper bread structure formation. The dough's pH was 6.9, critical for enzymatic activity and carbon dioxide production during fermentation. Chemically, the total phenolic content was 8.81 ± 0.44 mg GAE/g, highlighting the presence of bioactive compounds with antioxidant properties. Furthermore, antioxidant activity measured by the DPPH assay reached 29.57 ± 0.65 mg Trolox equivalent/g, reinforcing the dough's antioxidant potential. Microbiological analysis showed a total yeast count of 6.48 ± 0.04 log CFU/mL, reflecting the effective development of yeasts, particularly Saccharomyces cerevisiae, responsible for carbon dioxide production, essential for gluten network formation. These results demonstrate that the optimized fermented dough has a balanced profile of mineral composition, proteins, and antioxidant activity, directly contributing to the final bread's quality. The bread showed a total phenolic content of 13.69 ± 0.26 mg GAE/100 g, indicating a significant presence of phenolic compounds known for their antioxidant benefits. Additionally, antioxidant capacity measured by the DPPH assay reached 59.09 ± 2.00 mg Trolox equivalent/g, highlighting its potential. Physicochemically, the bread had a moisture content of 36.64%, ash content of 1.69%, total protein content of 9.80%, fat content of 1.02%, pH of 5.98, carbohydrate content of 50.84 g/100 g, and an energy value of 251.82 kcal/100 g. Significant antimicrobial activity was observed against Gram-positive bacteria such as Staphylococcus aureus and Bacillus cereus, although no inhibition was noted against Escherichia coli, suggesting selective action. In the shelf-life study, no microorganisms were detected until T2. However, from T4 onward, there was a progressive increase in the total mesophilic microorganism count, as well as molds and yeasts. This trend culminated in significant degradation at T6, with the presence of Bacillus cereus.
Breadmaking is an industrial process involving a series of ordered and sequential operations that lead to the production of a final product—bread. Bread is a fundamental food for all social classes, having achieved a transversal position in the dietary behavior of society. For this reason, the baking industry has reached a prominent economic position, as bread is one of the staple foods of the human daily diet. In this study, the focus was on the bread wheat variety Barbela, a traditional Portuguese cultivar known for its good productivity in low-fertility soils in highly acidic environments and its adaptability to different environmental conditions. The aim was to develop and characterize bread made with Barbela wheat flour T150, analyzing its microbiological, physicochemical, chemical properties, and antimicrobial activity. Barbela wheat flour showed a total phenolic content of 7.57 ± 0.14 mg GAE/g and significant antioxidant activity (32.49 ± 0.57 mg Trolox equivalent/g), demonstrating its potential as a source of bioactive compounds. Microbiological analysis revealed no contamination, ensuring compliance with food safety standards. Regarding physicochemical analysis, the flour had a moisture content of 11.12%, within regulatory limits, and an ash content of 1.58%, indicating a richness in minerals. The protein content was 12.65%, with a wet gluten content of 35.05% and dry gluten of 13.13%. These characteristics are essential for breadmaking, ensuring the proper gluten formation. During the breadmaking process, experiments were conducted to optimize fermentation conditions. A Plackett-Burman design was applied with 18 trials, testing 4 factors at 3 levels: fermentation time (1h, 3h, 5h), fermentation temperature (20°C, 30°C, 40°C), salt content (0.6, 1.0, and 4 g/L), and yeast content (1.0, 3.0, and 4.0 g/L). Based on the experimental results, the following optimal conditions were selected for bread preparation: 70 g/L of water, 100 g of flour, 1h fermentation at 25°C, and 1 g of salt and yeast. The optimized fermented dough yielded important results. Physicochemical analysis showed an ash content of 1.39%, indicating the mineral content of the sample, and a total protein content of 8.72%, a significant value to ensure gluten quality and proper bread structure formation. The dough's pH was 6.9, critical for enzymatic activity and carbon dioxide production during fermentation. Chemically, the total phenolic content was 8.81 ± 0.44 mg GAE/g, highlighting the presence of bioactive compounds with antioxidant properties. Furthermore, antioxidant activity measured by the DPPH assay reached 29.57 ± 0.65 mg Trolox equivalent/g, reinforcing the dough's antioxidant potential. Microbiological analysis showed a total yeast count of 6.48 ± 0.04 log CFU/mL, reflecting the effective development of yeasts, particularly Saccharomyces cerevisiae, responsible for carbon dioxide production, essential for gluten network formation. These results demonstrate that the optimized fermented dough has a balanced profile of mineral composition, proteins, and antioxidant activity, directly contributing to the final bread's quality. The bread showed a total phenolic content of 13.69 ± 0.26 mg GAE/100 g, indicating a significant presence of phenolic compounds known for their antioxidant benefits. Additionally, antioxidant capacity measured by the DPPH assay reached 59.09 ± 2.00 mg Trolox equivalent/g, highlighting its potential. Physicochemically, the bread had a moisture content of 36.64%, ash content of 1.69%, total protein content of 9.80%, fat content of 1.02%, pH of 5.98, carbohydrate content of 50.84 g/100 g, and an energy value of 251.82 kcal/100 g. Significant antimicrobial activity was observed against Gram-positive bacteria such as Staphylococcus aureus and Bacillus cereus, although no inhibition was noted against Escherichia coli, suggesting selective action. In the shelf-life study, no microorganisms were detected until T2. However, from T4 onward, there was a progressive increase in the total mesophilic microorganism count, as well as molds and yeasts. This trend culminated in significant degradation at T6, with the presence of Bacillus cereus.
Description
Keywords
Trigo Barbela pão Microbiológicas Compostos fenólicos Atividade antioxidante Físico-químicas