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Abstract(s)
Um muffin é um lanche doce, assado, popular, consumido normalmente ao pequeno almoço e ao lanche. A sua textura esponjosa e macia e o seu sabor adocicado são atributos procurados pelos consumidores, bem como sua fácil mastigação, o formato simétrico com o topo arredondado e acastanhado.
Um comportamento recente nos consumidores tem sido aliar a alimentação à procura de um estilo de vida mais saudável, à preferência por alimentos mais naturais, com propriedades funcionais e produtos mais sustentáveis. Essas tendências têm pressionado a indústria alimentar no sentido de desenvolver produtos com ingredientes naturais e com aporte de propriedades benéficas para a saúde dos seus consumidores. Um dos aspetos mais importantes no desenvolvimento de alimentos é a sua conservação, que hoje em dia depende de aditivos sintéticos ou artificiais. No entanto, devido a problemas relacionados com o consumo de aditivos alimentares e consequente toxicidade, procuram-se alternativas naturais e com menos ou nenhum efeito adverso, por exemplo, a adição de conservantes naturais derivados de plantas para estender o tempo de prateleira e evitar a sua deterioração. De entre as matrizes naturais consideradas como fontes de moléculas funcionais, encontram-se o alecrim, os orégãos e a cidreira, podendo ser utilizadas com esse propósito, pois apresentam uma variedade de fitoquímicos com grande atividade biológica.
Assim, o presente trabalho tem dois objetivos principais; por um lado a otimização da extração de compostos bioativos de plantas, e, por outro lado a utilização de extratos de alecrim, cidreira e orégãos como ingredientes conservantes e indutores de bioatividade, com vista a produzir muffins sem aditivos conservantes artificiais. A otimização foi feita com o auxílio do design fatorial fracionário, e utilizada a extração assistida por ultrassom para maximizar a quantidade de compostos fenólicos nos extratos, sendo também avaliada a atividade antimicrobiana e antioxidante. Após incorporação destes nos muffins, foi efetuada uma análise ao perfil nutricional, ácidos orgânicos, ácidos gordos, açúcares solúveis, além da cor e textura. Como esperado, a influência dos conservantes naturais assemelhou-se à utilização do sorbato de potássio sem alterar significativamente outros parâmetros nutricionais, químicos ou físicos dos muffins ao longo dos 8 dias de análise. Assim,
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confirma-se o potencial do uso dos extratos como conservantes naturais em substituição aos conservantes sintéticos.
A muffin is a sweet snack which is baked and usually consumed throughout the day, highly appreciated for its spongy and soft texture, sweet flavour, as well as its chewiness, symmetrical shape and rounded brownish top. A recent trend from consumers is a pursuit for a more adequate diet, allied to a healthier way of life, translated in the seek for healthier foods with functional properties. These tendencies have led the food industry to develop healthier foods with natural ingredients that can confer beneficial properties for their consumers. One of the most important aspects in the development of food is its preservation, which relies, nowadays, on synthetic or artificial food additives. However, due to problems related to the consumption of food additives and consequent toxicity, natural alternatives are sought with less or no adverse effect, for example, the addition of natural preservatives derived from plants to extend the shelf-life and prevent deterioration. Among the natural matrices, rosemary, oregano and lemon balm are interesting candidates due to the high number of functional molecules which can be used to preserve food. The present work has two main objectives; on the one hand the optimization of the phenolic fraction of extracts from lemon balm, oregano and rosemary, and, on the other, using the best extracts as preservative ingredients in muffins, to produce these snacks without artificial preservative additives. The optimization was done with the aid of factorial fraction design and using ultrasound-assisted extraction. Furthermore, the antioxidant and antimicrobial activities were also performed on these extracts prior to their incorporation in chocolate muffins. Then, the nutritional profile of these muffins was analysed, as well as the organic and fatty acids, soluble sugars, texture and color parameters were performed. As expected, the extracts showed as similar effect on preserving the muffins as sodium sorbate while not changing any other parameters of the muffins. This work shows that plant extracts can be alternatives to synthetic molecules.
A muffin is a sweet snack which is baked and usually consumed throughout the day, highly appreciated for its spongy and soft texture, sweet flavour, as well as its chewiness, symmetrical shape and rounded brownish top. A recent trend from consumers is a pursuit for a more adequate diet, allied to a healthier way of life, translated in the seek for healthier foods with functional properties. These tendencies have led the food industry to develop healthier foods with natural ingredients that can confer beneficial properties for their consumers. One of the most important aspects in the development of food is its preservation, which relies, nowadays, on synthetic or artificial food additives. However, due to problems related to the consumption of food additives and consequent toxicity, natural alternatives are sought with less or no adverse effect, for example, the addition of natural preservatives derived from plants to extend the shelf-life and prevent deterioration. Among the natural matrices, rosemary, oregano and lemon balm are interesting candidates due to the high number of functional molecules which can be used to preserve food. The present work has two main objectives; on the one hand the optimization of the phenolic fraction of extracts from lemon balm, oregano and rosemary, and, on the other, using the best extracts as preservative ingredients in muffins, to produce these snacks without artificial preservative additives. The optimization was done with the aid of factorial fraction design and using ultrasound-assisted extraction. Furthermore, the antioxidant and antimicrobial activities were also performed on these extracts prior to their incorporation in chocolate muffins. Then, the nutritional profile of these muffins was analysed, as well as the organic and fatty acids, soluble sugars, texture and color parameters were performed. As expected, the extracts showed as similar effect on preserving the muffins as sodium sorbate while not changing any other parameters of the muffins. This work shows that plant extracts can be alternatives to synthetic molecules.
Description
Keywords
Otimização Extratos de plantas Aditivo alimentar Muffins