Browsing by Author "Sanches-Silva, Ana"
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- Active Edible PackagingPublication . Barbosa, Cássia; Andrade, Mariana; Vilarinho, Fernanda; Fernando, Ana; Sanches-Silva, AnaDefinition: Active edible packaging is a food packaging made of comestible bioproducts and active compounds that interacts with the food. The bioproducts, usually biopolymers, must be recognized as safe and with characteristics to be consumed by humans—comestible—and not toxic and capable of carrying an active compound, like anti-browning agents, colorants, flavors, nutrients, antimicrobial and/or antioxidant compounds, in order to extend the product shelf-life, reduce contamination and maintain or even enhance the nutritional value.
- Active Packaging: application of natural antioxidantsPublication . Sanches-Silva, Ana; Costa, Denise; Albuquerque, T.G.; Castilho, Maria Conceição; Ramos, Fernando; Machado, Ana V.; Costa, H.S.Natural antioxidants applied in Active food Packaging: Food oxidation; Antioxidants; Food Packaging; Active Packaging; Legislation; Natural antioxidants.
- Advances in phenolic compounds analysis of aromatic plants and their potential applicationsPublication . Carvalho-Costa, Denise; Costa, H.S.; Albuquerque, T.G.; Ramos, Fernando; Castilho, Maria Conceição; Sanches-Silva, AnaBackground: Aromatic plants may contribute for human health promotion due to their antioxidant properties and also by replacing added salt in foods. Phenolic compounds are one of the major groups contributing for aromatic plants properties, including the prevention of cancer, cardiovascular and neurodegenerative diseases. Scope and approach: This review focuses on the main uses of aromatic plants generally recognized as safe (GRAS) and overviews the extraction, purification and analytical methods used to determine phenolics in these food matrices. The current state of the art is evaluated and future trends in the analysis of these compounds and food industry applications are discussed. Key findings and conclusions: In general, aromatic plants are complex matrices regarding their content on phenolic compounds. Their composition can be affected by the chemical structure of the studied analytes, the selected methods, the composition/nature of the aromatic plant and storage conditions. The most usual separation technique to determine these compounds is High Performance Liquid Chromatography (HPLC) coupled with ultraviolet (UV) or diode array detectors (DAD), although the use of mass spectrometry (MS) detectors is increasing. The future trends include the use of more sophisticated and automated techniques in order to reduce both analysis time and the amount of solvents used. Food industry widely uses aromatic plants, but other industries like food packaging, cosmetics, perfumery and pharmaceutical can also benefit from their properties.
- Antioxidant activity evaluation of Rose apple and Surinam cherry from Madeira IslandPublication . Ferreira, Joana O.; Costa, Denise; Castilho, Maria Conceição; Sanches-Silva, Ana; Albuquerque, T.G.; Ramos, Fernando; Costa, H.S.Rose apple or jambu (Syzygium jambos L.), Surinam cherry (Eugenia uniflora L.) are tropical fruits from Madeira Island. Rose apple is reddish and rose-scented while Surinam cherry is a small eight-ribbed fruit, of about 2-3 cm and ranges from orange to red colour. The goal of this study was to evaluate their antioxidant activity using two methods, β-carotene bleaching assay and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging assay. The extract concentration providing 50% inhibition of DPPH radical (EC50) was calculated from the graph of scavenging effect percentage against extract concentration in the solution. The β-carotene bleaching assay studied the ability of the extracts to avoid the oxidative bleaching of β-carotene in a β-carotene/linoleic acid emulsion. DPPH• reduction assay showed higher antioxidant activity of Surinam cherry (EC50 = 3.74 ± 0.09 mg/mL) than Rose apple (EC50 = 10.0 ± 0.21 mg/mL). β-carotene bleaching assay showed an antioxidant activity capacity (AAC) also higher for Surinam cherry (AAC=831.5) than for Rose apple (AAC=582.5). Surinam cherry showed better antioxidant capacity in both trials. Madeira Island has many tropical fruits with antioxidant activity, which could improve health status, by preventing diseases caused by oxidative stress, since these bioactive compounds can help to counteract the oxidizing agents. The results of this study indicate that both Rose apple and Surinam cherry have potential as antioxidants sources. In the future more research is needed in order to identify the compounds responsible for the antioxidant properties.
- Antioxidant activity of phytochemicalsPublication . Patras, Ankit; Yuan, Yvonne; Costa, H.S.; Sanches-Silva, Ana
- Antioxidantes naturales aplicados a envases activos alimentarios: evolución recientePublication . Sanches-Silva, Ana; Costa, Denise; Albuquerque, T.G.; Castilho, Maria Conceição; Ramos, Fernando; Machado, Ana V.; Costa, H.S.Recent Advances in Antioxidant Active Food Packaging: Food oxidation; Antioxidants; Food Packaging; Active Packaging; Legislation; Natural antioxidants.
- Bisfenol A (BPA)Publication . der Kellen, Ana Van; Vilarinho, Fernanda; Andrade, Mariana; Figueira, Maria Eduardo; Sanches-Silva, AnaPoster de divulgação sobre Bisfenol A (BPA) informando sobre: O que é? Onde pode estar presente? Efeitos na saúde; Como ocorre a contaminação dos alimentos? Prevenção.
- Capacidade antioxidante de óleos essenciais para potencial incorporação em embalagens alimentares ativasPublication . Ribeiro-Santos, Regiane; Melo, Nathália R.; Costa, H.S.; Sanches-Silva, AnaOs óleos essenciais (OEs) são produtos aromáticos naturais, que contêm na sua composição misturas de compostos tais como: terpenos, fenóis, aldeídos e ésteres, que variam com a espécie e a parte da planta utilizada. Esses compostos podem conferir ação antioxidante aos OEs que, quando adicionados a alimentos ou incorporados em embalagens alimentares, podem minimizar a oxidação lipídica. O objetivo deste trabalho foi determinar a capacidade antioxidante dos OEs comerciais de alecrim (Rosmarinus officinalis L.), canela (Cinnamomum cassia L. e Cinnamomum zeylanicum L.), e manjericão (Ocimum basilicum L.) e avaliar a contribuição dos seus principais constituintes. A análise de capacidade antioxidante foi realizada pelos métodos da inibição do radical livre DPPH e do branqueamento do β-caroteno. O OE de C. zeylanicum obteve a maior capacidade antioxidante no ensaio do radical DPPH, apresentando uma concentração de extrato necessária para inibir 50 % do radical DPPH (EC50) de 0,14 g/L, seguida pelo OE de alecrim (EC50= 8,49 g/L). Os OEs de C. cassia e O. basilicum mostraram baixa eficácia. Entre as substâncias puras, o eugenol destacou-se com EC50 de 0,078 g/L, não diferindo significativamente (p > 0,05) do OE de C. zeylanicum. Enquanto que, o cinamaldeído, metil chavicol, eucaliptol e α-pineno tiveram muito pouca atividade, sem diferenças significativas (p > 0,05) entre eles. O OE de C. zeylanicum também apresentou ter maior capacidade antioxidante pelo método do branqueamento do β-caroteno, apresentando um coeficiente de atividade antioxidante (CAA) de 927,0, seguido pelo OE de alecrim (68,3). O eugenol observou-se um CAA de 804,46, seguido pelo α-pineno (29,40), metil chavicol (27,34), cinamaldeído (20,60) e eucaliptol (1,84). Não houve diferenças (p> 0,05) entre os OEs de manjericão e o de C. cassia e entre as substâncias puras α-pineno e metil chavicol. A elevada capacidade antioxidante do OE de C. zeylanicum está relacionada com a presença de eugenol como componente maioritário, enquanto que os efeitos antioxidantes dos OEs de C. cassia e de O. basilicum relacionam-se com o cinamaldeído e o metil chavicol, respectivamente. O eucaliptol e o α-pineno apresentam-se em maior percentagem no OE de alecrim. Dos OEs estudados neste trabalho, o de C. zeylanicum foi o que apresentou maior capacidade antioxidante, sendo o que apresenta maior potencial de utilização na preparação de embalagens alimentares ativas antioxidantes.
- Cardoon (Cynara cardunculus L.): different multipurpose food industry applicationsPublication . Barbosa, Cássia; Andrade, Mariana; Vilarinho, Fernanda; Fernando, Ana; Sanches-Silva, AnaCynara cardunculus L. (Asteraceae) is a multipurpose crop native to the Mediterranean area, commonly called cardoon. It comprises three botanical varieties: the globe artichoke (var. scolymus (L.) Fiori), the cultivated cardoon (var. altilis DC.), and the wild cardoon (var. sylvestris (Lamk) Fiori). Cardoon can develop in adverse climate conditions, low inputs, high temperature, severe drought, and infertile soils as a resistant species. Yet, it can persist for several years, re-sprouting annually. Cardoon can be used for different purposes due to its composition. For instance, the fleshy stems and the immature heads are used in Mediterranean cuisine. The flowers are used in the production of some cheeses as vegetal rennet. In traditional medicine cardoon is used due to its high content in cynarin and silymarin. Kidneys and liver malfunction, high blood cholesterol levels, diabetes, and cancer are some of the medicinal applications. On the other hand, cardoon’s by-products, leaves, stems and seeds, can be used to produce biomass for energy, biodiesel, seed oil, animal feed and paper pulp. Cardoon’s leaves bioactive properties (e.g.: antioxidant and antimicrobial activities) are due to its excellent polyphenol profile, rich in chlorogenic acid and flavonoids. As leaves represent, on average, about 60% of total cardoon waste, in the context of a circular economy it is essential to take advantage of its composition in bioactive compounds. Concerning the food industry, leaves, and leaves extracts bioactivity may represent an added value as a food additive, as an ingredient in developing a novel food, or in active food packaging to control lipid oxidation and microbial deterioration. Hence, this study aims to address the current food applications of cardoon’s leaves and their functional properties and explore new potential ones adding value to its properties.
- Determinação do ergosterol no cogumelo ostra (Pleurotus ostreatus) cultivado em borras de café e palha de trigoPublication . Ricardo, Sofia; Sanches-Silva, Ana; Ramos, Fernando; Castilho, Maria ConceiçãoUm dos cogumelos comestíveis que tem suscitado maior interesse nos últimos anos é o Pleurotus ostreatus, conhecido como cogumelo ostra, devido à facilidade de cultivo e ao seu grande potencial económico e qualidade nutricional. Existe, assim, a necessidade de estudar a sua composição em nutrientes e compostos bioativos para valorizar o seu cultivo. Este estudo teve por objetivo determinar o teor de ergosterol, por Cromatografia Líquida de Alta Eficiência acoplada a detetor de Ultravioleta-Visível, do cogumelo Pleurotus ostreatus cultivado em diferentes substratos, nomeadamente, borras de café e palha de trigo. Verificou-se que as amostras de cogumelo P. ostreatus cultivadas em borras de café apresentaram uma concentração de ergosterol superior (4,06 ± 0,32 mg/g de matéria seca) relativamente às amostras da mesma espécie de cogumelo cultivadas em palha de trigo (3,34 ± 0,19 mg/g de matéria seca). O uso das borras de café no substrato de crescimento de cogumelos ostra permitiu um aumento da concentração de ergosterol. No futuro seria de todo o interesse avaliar a influência do uso deste subproduto no substrato de crescimento de outras espécies comestíveis de cogumelos e no teor de outros compostos bioativos.