Browsing by Author "Silva, M.A."
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- 4-Hydroxynonenal: a parameter of quality and safety of vegetable oilsPublication . Albuquerque, T.G.; Oliveira, M.B.P.P.; Silva, M.A.; Costa, H.S.Due to several factors, namely social, economic and technical, people have less time to spend in food preparation. Consequently, the consumption of fried and pre-fried foods has been increasing due to its easy preparation. This behaviour has been linked to an increase in the intake of fats and oils subjected to high temperatures. Oils and fats are previously processed (refining) to improve their quality, stability and safety. Despite the removal of a large amount of impurities from the oil that influence negatively their quality, some processing conditions can often originate new compounds with additional health hazards.
- Alimentos funcionais: perceção e hábitos de consumoPublication . Silva, M.A.; Albuquerque, T.G.; Oliveira, M.B.P.P.; Alves, R.C.; Costa, H.S.Introdução: O aumento da exigência dos consumidores em relação aos alimentos e aos seus benefícios para a saúde promove a necessidade de desenvolver alimentos funcionais com ingredientes que, de alguma forma, melhorem a saúde de quem os consome. Esses ingredientes podem contribuir para reduzir o risco de algumas doenças, como doenças cardiovasculares, cancro, obesidade, osteoporose, entre outras. Objetivos: Este trabalho teve como objetivo a avaliação da perceção do consumidor e os seus hábitos de consumo relativamente a alimentos funcionais. Métodos: Em 2019, foi aplicado um questionário online, disponibilizado através de email e redes sociais. O questionário era composto por 2 partes: i) dados gerais e sociodemográficos e ii) alimentos funcionais. No final do questionário, e após a submissão da resposta, foi disponibilizada uma breve explicação sobre o tema. Resultados: Participaram 233 indivíduos (18 aos 77 anos). Apenas 58% dos inquiridos dizem saber o que são alimentos funcionais, apesar de 87% referirem que sabem que existem alimentos com atributos adicionais e efeitos positivos na saúde e bem-estar. Desses 87%, 80% referem que já consumiram este tipo de alimentos, e 85% indicam que o principal motivo do consumo são os seus benefícios para a saúde. Noventa e sete por cento (97%) da população inquirida considera importante melhorar o nível de informação relativamente a este tipo de alimentos, indicando as campanhas de informação, criação de símbolos para a rápida identificação do produto/benefício e educação nas escolas como algumas das possíveis medidas a tomar. Conclusões: Com os resultados obtidos neste trabalho foi possível verificar a importância da criação de medidas que possibilitem melhorar o nível de informação da população em relação aos alimentos funcionais e aos seus potenciais benefícios para a saúde.
- An innovative food product based on melon by-product: mineral profilePublication . Silva, M.A.; Albuquerque, T.G.; Santo, L.E.; Alves, R.C.; Oliveira, M.B.P.P.; Costa, H.S.The demand for foods with positive health effects has increased as a result of the notable expansion in interest in health, food, and well-being in Europe and other developed countries. Fruit by-products are a good source of important nutrients like dietary fiber, fat, protein, vitamins, minerals, and other bioactive elements. In recent years, research has been conducted to determine whether these by-products may be used to enrich food products, with the goal of producing foods that are more nutritious and may have positive health effects. The objective of this study was to develop a muffin formulation based on melon peel flour and evaluate its composition regarding macroelements and trace elements (essential and non-essential). In 2021, melon peels were recovered from melon production and distribution companies, located in Torres Vedras and Rio Maior (Portugal). The melon peels were manually separated, dehydrated (50 ºC, 18h), homogenised, and sieved until a fine powder (melon peel flour) was obtained. A traditional recipe for muffins (control sample) and an innovative muffin, where the wheat flour was replaced by melon peel flour were prepared. The macroelements (Ca, Mg and P) and trace elements were analysed by inductively coupled plasma mass spectrometry and sodium and potassium were analysed by flame atomic absorption spectrometry. Regarding the results obtained, the main macroelements present in the melon peel flour were potassium (26 ± 0,7 mg/g) and calcium (8 ± 0,1 mg/g) and the most abundant essential trace elements were iron, manganese and zinc. By replacing wheat flour with melon peel flour, the magnesium, calcium and potassium contents increased. The highest increase was observed for potassium content (4 mg/g). Regarding essential trace elements, the incorporation of melon peel flour increased the content of iron, manganese and molybdenum. The melon peel flour can be considered a good source of macroelements such as potassium, calcium and phosphorus, and essential trace elements such as iron, manganese and zinc. The incorporation of melon peel flour allowed the development of a formulation rich in potassium, phosphorus and magnesium. This by-product has the potential to improve food security, nutrition, and economic well-being on a global scale, as well as the general health and well-being of people, animals, and the environment, supporting the One Health concept.
- An innovative food product based on the recovery of melon by-productsPublication . Silva, M.A.; Costa, H.S.; Alves, R.C.; Oliveira, M.B.P.P.; Albuquerque, T.G.Food reformulation or development of new foods is necessary to improve the nutritional profile of energy-dense foods (high fat, sugar and salt contents) or to reduce the content of ingredients or to decrease the amount of nutrients of concern. Biscuits are bakery goods characterized by high sugar and fat content, but are also very palatable foods, highly appreciated. AIMS: To develop an innovative biscuit with enhanced nutritional properties, based on the recovery of melon by-products, contributing to healthier food options. In 2022, melon peels were recovered from producers of melon fruits, mainly discarded fruits which do not correspond to market needs in terms of size, and/or shape, or colour. Melon peels were dehydrated and homogenised until a fine powder (melon peel flour) was obtained. A traditional recipe for biscuits (control sample) and an innovative biscuit, where 50% of the wheat flour was replaced by melon peel flour, were prepared. The nutritional composition of both products was evaluated. The control biscuit is characterized by its poor nutritional quality, namely due to its low dietary fibre (1.53 ± 0.3 g/100 g) and high available carbohydrates contents. By replacing, wheat flour with melon peel flour, dietary fibre content increases to 14.7 ± 0.6 g/100 g. Since the dietary reference intake for adults for fibre is 25 g/day, one portion of the innovative biscuit (35 g) can contribute with 21% of the recommended needs. Moreover, according to Regulation (EU) n.º 1924/2006, this innovative product can be claimed as high fibre. This work demonstrates not only that melon peel is an excellent source of dietary fibre, that contributes to enhancing the nutritional quality of biscuits, but also that it is possible to reduce the economic, social and environmental impacts of these by-products that up to now are discarded.
- An update on processed foods: Relationship between salt, saturated and trans fatty acids contentsPublication . Albuquerque, T.G.; Santos, J.; Silva, M.A.; Oliveira, M.B.P.P.; Costa, H.S.To update the current situation on salt, fat and fatty acid composition of processed foods, a study including a wide range of different food categories was conducted in Portugal. Different validated analytical techniques were used, and a PCA and correlation analysis were conducted to establish a trend between the different components in each food category. The highest salt content was found in snacks, fast-food, sauces and ready-to-eat meals, while the saturated fatty acids were higher (p < .05) in bakery products, cookies, biscuits and wafers, and snacks. The highest levels of trans fatty acids were found in the fast-food group, followed by the snacks, potato and potato-products and bakery products. A significant positive correlation (p < .05) was found between salt and fat content in ready-to-eat meals and in the potato and potato-products. The PCA analysis identified total fat, low trans fatty acids and high salt content as distinctive characteristics of some food categories.
- Análise comparativa do poder antioxidante de frutas e hortícolasPublication . Santos, I.C.; Albuquerque, T.G.; Silva, M.A.; Costa, H.S.Os antioxidantes são substâncias que, quando presentes em baixas concentrações comparativamente ao substrato oxidável, inibem ou retardam significativamente a oxidação desse substrato. Embora o organismo humano possua um sistema de defesa antioxidante bastante complexo, que o protege contra os efeitos nefastos de várias reações de oxidação, muitas vezes não é suficiente para evitar danos a nível celular. Diversos estudos epidemiológicos demonstram existir uma correlação positiva entre o consumo regular de hortícolas e frutas (alimentos naturalmente ricos em compostos antioxidantes) com a diminuição do stress oxidativo e aparecimento de doenças crónicas. Os compostos antioxidantes assumem assim um papel de extrema importância no nosso organismo e a sua determinação tem suscitado um grande interesse a nível científico. O objetivo deste trabalho foi determinar a atividade antioxidante de hortícolas e frutas amplamente disponíveis no mercado, bem como realizar uma análise comparativa dos seus teores. No ano de 2016 foram adquiridas em grandes superfícies comerciais da região de Lisboa 14 tipos de frutas (abacate, abacaxi, banana, framboesas, kiwi, laranja, limão, manga, meloa, mirtilos, morangos, papaia, pera e pêssego) e 12 tipos de hortícolas (abóbora, alface iceberg, beringela, beterraba, brócolos, cenoura, courgette, couve roxa, espinafres, gengibre, pepino e tomate). A atividade antioxidante foi determinada utilizando dois métodos, 2,2-difenil-1-picril-hidrazilo (DPPH•) e o poder de redução férrica (FRAP). De acordo com os resultados obtidos verificou-se que as amostras analisadas apresentaram resultados distintos consoante o método utilizado. Para o método de DPPH• as amostras que apresentaram maior atividade antioxidante foram as framboesas (EC50 = 2,4 mg/mL), a couve rouxa (EC50 = 3,2 mg/mL) e os mirtilos (EC50 = 5,6 mg/mL) enquanto para o método FRAP foram o kiwi (217 ± 3,9 μg de equivalentes de trolox/mL), os morangos (214 ± 2,6 μg de equivalentes de trolox/mL) e a laranja (213 ± 3,5 μg de equivalentes de trolox/mL). Relativamente às amostras com menor atividade antioxidante, podemos destacar o pepino, para o método FRAP e a cenoura para o método de DPPH•. É importante referir que para o método de DPPH• não foi possível aferir a atividade antioxidante de algumas amostras (alface, courgette, abóbora, pepino e meloa). Considerando as amostras analisadas, verificamos que a atividade antioxidante variou consideravelmente consoante o tipo de frutas e hortícolas analisados, existindo em ambos os casos exemplos de alimentos com elevado e baixo poder antioxidante. No entanto, considerando as 10 amostras com maior atividade antioxidante para os dois métodos verificamos que apenas 3 destas amostras correspondem a hortícolas, sendo as restantes amostras correspondentes a frutas.
- Analysis of total vitamin C, ascorbic acid and dehydroascorbic acid in red fruits and green leafy vegetables by HPLC-PDAPublication . Salgado, N.; Silva, M.A.; Costa, H.S.; Figueira, M.E.; Albuquerque, T.G.Ascorbic acid (AA), also known as vitamin C, is an essential micronutrient due to its role in human development and wellbeing since it has antioxidant properties and is involved in the production of proteins like collagen. [1] It has been associated with several health benefits: reduced risk of mortality, cardiovascular disease, different types of cancer, and respiratory and neurological issues. [2] Despite being mainly found in citrus species, AA also exists in other fruits and vegetables. This study aimed to assess the variability of vitamin C content in red fruits (strawberry, raspberry and blueberry) and green leafy vegetables (spinach and lettuce) from different brands and supermarkets, measuring total vitamin C, by high-performance liquid chromatography with photodiode array detection (HPLC-PDA), an extremely sensitive and validated method. According to our results, brand B of strawberry was the richest in total vitamin C (51.3 mg/100 g) with 45 mg/100 g of AA and 6.27 mg/100 g of DHA, followed by brand A of raspberry (44.7 mg/100 g), being the majority AA. On the contrary, all brands of blueberry did not contain any form of vitamin C and brand B of lettuce had 5.01 mg/100 g of total vitamin C, reporting the lowest detectable value. Within the different brands, total vitamin C ranged between 37.4-51.3, 20.8-44.7, 5.01-5.13 and 10.1-12.4 mg/100 g for strawberry, raspberry, lettuce and spinach, respectively. Thus, red berries seem to have higher quantity of vitamin C than green leafy vegetables, except for blueberry. Differences between the same food of distinct brands can be justified due to cultivation practices, ripeness, environmental and soil conditions, as well as storage conditions since vitamin C is sensitive to heat, light, and oxygen. Furthermore, consulting Regulation Nº 1169/2011, which indicates 80 mg of vitamin C as daily reference dose for adults, consuming 1 portion (160 g) of brand B of strawberry will make you achieve 103% of the recommendation. References: [1] Santos, K et al. (2022) Essential features for antioxidant capacity of ascorbic acid (vitamin C). J Mol Model., 28, 1-8; [2] Xu, K et al. (2022) Vitamin C intake and multiple health outcomes: an umbrella review of systematic reviews and meta-analyses. Int J Food Sci Nutr., 73, 588-599.
- Analysis, Identification, and Quantification of Anthocyanins in Fruit JuicesPublication . Albuquerque, T.G.; Silva, M.A.; Oliveira, M.B.P.P.; Costa, H.S.Anthocyanins are naturally present in a wide range of plant foods, and are usually associated with the orange, pink, red, violet, and blue colors of fruits, such as berries, plums, cherries, pomegranates, citrus fruits, among others. Juices produced from fruits, especially berries, such as black currants, elderberries, chokeberries, or sour cherries, are a source of vitamins and other compounds, such as anthocyanins. High- or ultra-high-performance liquid chromatography techniques coupled with diode array detection or mass spectrometry detection, are by far the most widely used techniques for the qualitative and quantitative analysis of anthocyanins in fruit juices. Anthocyanin content in fruit juices can be used as quality control parameters to check authenticity. Significant differences can be found for anthocyanin content in the same type of juice, but the profile of anthocyanins should be similar.
- Aplicação das metas da EIPAS em produtos de padaria e pastelariaPublication . Rodrigues, H.I.; Costa, H.S.; Silva, M.A.; Oliveira, M.B.P.P.; Albuquerque, T.G.Introdução: A implementação e adoção de hábitos alimentares saudáveis é apontada como uma medida com um papel protetor e preventivo da saúde dos indivíduos. No entanto, apesar de já existirem diversos programas neste sentido, é necessário continuar a desenvolver esforços para serem fornecidas opções alimentares mais saudáveis. É preciso continuar a promover a educação alimentar dos consumidores, sobretudo no ato da compra, de forma a garantir escolhas alimentares conscientes e informadas. Objetivos: Avaliar a conformidade e adequação nutricional de produtos de padaria e pastelaria, relativamente aos teores de açúcares e sal, de acordo com a informação contida nos rótulos, considerando as metas estabelecidas na Estratégia Integrada para a Promoção da Alimentação Saudável (EIPAS). Métodos: Foram recolhidas as informações nutricionais de 163 produtos de padaria e pastelaria a partir de plataformas de venda online. Estes foram divididos em 7 categorias (croissants, pães de leite, donuts, napolitanas, travesseiros, brownies, tortas, muffins/madalenas) e para a avaliação da qualidade nutricional foram selecionados os valores declarados dos teores de açúcares e sal. A avaliação da adequação nutricional foi realizada através das metas definidas pela EIPAS. Resultados: Relativamente ao teor de açúcares, 99% dos produtos (n=161) tem um valor superior a 5 g de açúcares, sendo a média dos valores 28,9 g/100 g. Em relação ao sal, apenas 8% (n=13) tem um valor inferior relativamente à meta definida (0,3 g/100 g). O grupo dos pães de leite com e sem recheio é o que mais contribui para estes valores. Conclusões: Os géneros alimentícios analisados apresentam teores elevados de açúcares e sal, evidenciando assim a importância da definição de estratégias para reformulação destes alimentos de forma a obter-se uma redução gradual e efetiva dos teores destes nutrientes, e promover a Saúde Pública da população.
- Application of an HPLC method for the quality control of vitamin C content in foods for infantsPublication . Silva, M.A.; Albuquerque, T.G.; Oliveira, M.B.P.P.; Costa, H.S.Vitamin C is an important water-soluble vitamin that humans are not able to synthesize, so it needs to be provided by the diet. Babies less than 1 year usually do not eat foods naturally rich in vitamin C, so the main sources are breast milk and/or infant formulas. Regulation (EU) No. 609/2013, Commission Delegated Regulation (EU) No. 2016/127 and Ministério da Agricultura, do Desenvolvimento Rural e das Pescas (2008) establishes compositional and information requirements for food intended for infants and young children [1-3]. Adequate intake of vitamin C is very important to assure children’s good health and development, so it is crucial to evaluate vitamin C content in this type of foods. The aim of this study was to validate a high-performance liquid chromatography (HPLC) method for the quality control of vitamin C content in infant foods (2 infant formulae (IF), 2 follow-on formulae (FF), 2 processed cereal-based foods (PCF) and 2 baby foods (BF)). In 2016, the infant foods were collected from major supermarket chains and parapharmacies in the region of Lisbon (Portugal). Two of the acquired samples were already ready-to-use, while the remaining samples were prepared according to manufacturer’s instructions. Separation and quantification of vitamin C was carried out on an Alliance 2695 HPLC system, with diode array detection (DAD), using a SynergiTM Hydro-RP analytical column (150 x 4.6 mm I.D., 4.0 μm particle size). Samples were monitored at 245 nm. The HPLC-DAD analytical method was validated for selectivity, linearity, LOD, LOQ, precision and accuracy, using an infant formula. Calibration curves were linear over the range 1-100 µg/mL. The achieved LOD and LOQ were 0.026 and 0.086 µg/mL, respectively. Vitamin C content in the analysed samples ranged from 1.5 ± 0.01 to 178 ± 1.01 mg/100 g for BF1 and PCF2, respectively. The developed method is rapid, specific, precise and accurate, for the quantification of vitamin C in different categories of foods for infants and young children, showing satisfactory data for all the tested parameters. Since this type of food products are very important for such young and vulnerable consumers, regulation and assurance of an adequate intake of essential nutrients, like vitamin C, is extremely important for a healthy development. References: [1] European Parliament/Council of the European Union. (2013). Regulation (EU) No 609/2013 of the European Parliament and of the Council of 12 June 2013 on food intended for infants and young children, food for special medical purposes, and total diet replacement for weight control. Official Journal of the European Union, L181, 35-56. [2] European Commission. (2016). Commission Delegated Regulation (EU) 2016/127 of 25 September 2015 supplementing Regulation (EU) No 609/2013 of the European Parliament and of the Council as regards the specific compositional and information requirements for infant formula and follow-on formula. Official Journal of the European Union, L25, 1-29. [3] Ministério da Agricultura, do Desenvolvimento Rural e das Pescas (2008). Decreto-Lei n.º 53/2008 de 25 de Março. Diário da República, 1ª série - Nº 59, 1667-1674.