49 research outputs found

    From maize flour to bread: assessing the impact of processing on phenolic and volatile composition

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    Broa is a Portuguese ethnic bread traditionally prepared from maize open pollinated varieties (OPVs). These traditional varieties have been threatened by the progressive introduction of hybrid varieties, which do not possess the ability to produce high-quality broas and are less resilient to adverse environmental conditions. Scarce scientific studies have been reported regarding the nutritional and sensorial quality of broas and traditional Portuguese maize varieties. This work aimed to address this gap by providing information on the phenolic and volatile composition of broas and maize OPVs, important quality parameters in foods, related to health benefits and sensory attributes. Results showed that Portuguese maize OPVs and broas are a valuable source of phenolic compounds, in particular hydroxycinnamic acids and hydroxycinnamic acid amides (HCAAs). Several HCAAs were tentatively identified for the first time. Phenolic compounds not only resisted to the bread making process, but their free content also increased, suggesting that their bioaccessibility was improved. The traditional OPVs and corresponding broas showed higher phenolic contents when compared with a commercial maize flour and broa. The major volatiles detected in maize flours and broas were aldehydes derived from lipid oxidation reactions. Other compounds, derived from bread making, as pyranones, were also detected in broas. According to the results from a sensory panel evaluation, broas with higher contents in pyranones and lower in aldehydes were preferred by the consumers. Phenolic compounds appear to inhibit lipid oxidation reactions and increase browning reactions during bread making and, consequently, origin broas with better sensory characteristics. In addition, results suggested that a more advanced technique (comprehensive two-dimensional gas chromatography) is able to unveil relevant volatile compounds, since it allowed the detection of minor volatiles which may significantly influence broas overall aroma, as sulphur compounds. Overall, the results obtained in this work reinforce the importance of preserving these valuable genetic resources.A broa é um pão tradicional português preparado originalmente a partir de variedades de milho de polinização aberta. Estas variedades tradicionais têm sido ameaçadas pela introdução progressiva de variedades híbridas, menos resistentes a condições ambientais adversas e que originam broas de qualidade inferior. Existem poucos estudos científicos sobre a qualidade nutricional e sensorial das broas e das variedades de milho portuguesas. Este trabalho teve como objetivo colmatar esta lacuna, reunindo dados sobre a composição fenólica e volátil das variedades de milho tradicionais e broas, importantes parâmetros de qualidade alimentar, relacionados com características sensoriais e possíveis benefícios para a saúde. Os resultados demonstraram que as variedades de milho tradicionais portuguesas e respetivas broas são uma fonte importante de compostos fenólicos, em particular de ácidos hidroxicinâmicos e amidas de ácidos hidroxicinâmicos (HCAAs). Foram putativamente identificadas novas HCAAs que não tinham sido previamente reportadas. Os compostos fenólicos não apenas resistiram ao processo de panificação, como o seu teor livre aumentou, indicando uma melhoria na sua bioacessibilidade. As variedades tradicionais de milho e respetivas broas apresentaram teores superiores de compostos fenólicos, quando comparadas com uma farinha de milho e broa comercial. Os principais compostos voláteis detetados nas farinhas de milho e broas foram aldeídos derivados de reações de oxidação lipídica. Também foram identificados compostos resultantes do processo de panificação das broas, como piranonas. De acordo com os resultados de uma avaliação sensorial, as broas preferidas pelos consumidores apresentaram teores superiores em piranonas e inferiores em aldeídos. Os compostos fenólicos aparentam inibir as reações de oxidação lipídica e aumentar as reações que ocorrem durante o processo de cozedura e, consequentemente, originam broas com melhores características sensoriais. Adicionalmente, os resultados mostraram que a utilização de uma técnica mais avançada (cromatografia gasosa bidimensional abrangente) permite a deteção de voláteis minoritários, tais como compostos com enxofre, que podem influenciar significativamente o aroma das broas. De modo geral, os resultados obtidos neste trabalho reforçam a importância da preservação destes preciosos recursos genéticos

    Colaboração online: uma estratégia para o desenvolvimento profissional de professores

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    Neste texto colocaremos em discussão, de forma predominante, o referencial teórico que norteou uma pesquisa de doutoramento acerca do desenvolvimento profissional de professores de História da Rede Municipal de Ensino de Belo Horizonte/Brasil, que vivenciaram um processo de formação e consolidação de um grupo colaborativo, mediado pelas tecnologias de informação e comunicação aplicadas à educação - TICE. Destacamos como a colaboração online pode ser potencializadora do desenvolvimento profissional de professores e apresentamos exemplos desta interacção mediadas pela ferramenta E-group. A partir do conceito de desenvolvimento profissional adoptado por Garcia (1999) - como o conjunto de processos e estratégias que facilitam a reflexão dos professores sobre a sua prática, que contribui para que os professores gerem conhecimento prático, estratégico e sejam capazes de aprender com sua experiência - acreditamos que o grupo colaborativo pode ser um espaço desencadeador e propício para que essas reflexões ocorram.In this communication to explore, the predominant form, the theoretical framework that guided a doctoral research on the professional development of teachers of history of the Municipal School of Belo Horizonte, Brazil, which experienced a process of formation and consolidation of a collaborative group Mediated by information and communication technologies applied to education - TICE. We highlight how online collaboration can be an aggravator of the professional development of teachers and provide examples of this interaction is mediated by E-tool group. From the concept of professional development adopted by Garcia (1999) - as the set of processes and strategies that facilitate teachers' reflection on their practice, which helps teachers to manage knowledge, strategy and are able to learn from their experience - we believe the group may be a collaborative work space is conducive to these thoughts occur

    As crianças brincam ou trabalham? Conceções de crianças e profissionais em Jardim de Infância

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    Relatório de Prática de Ensino Supervisionada apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Educação Pré-EscolarEste relatório surge no âmbito da Unidade Curricular Prática Profissional Supervisionada II, inserida no plano de estudos do Mestrado em Educação Pré-Escolar. O mesmo realça o período em que me integrei como estagiária num Jardim de Infância (JI), no qual estive desde 17 de outubro de 2022 a 13 de fevereiro de 2023, com um grupo de crianças com idades compreendidas entre os três e os seis anos e com a respetiva equipa educativa (educadora de infância e assistente operacional). A investigação emerge do projeto que desenvolvi com as crianças, no qual estas manifestaram as suas opiniões acerca do que as crianças fazem: brincam, trabalham e/ou fazem ambos. Assim, defini os seguintes objetivos: i) conhecer as conceções das crianças da sala 3 sobre se “As crianças brincam e/ou trabalham?”; ii) conhecer as conceções das profissionais da sala 3 acerca da mesma questão. Procurei, ainda, compreender como os tempos-espaços do JI influenciam a projeção de momentos direcionados para o brincar e para o trabalhar e como a prática pedagógica do/a educador/a influencia o modo como as crianças consideram os diferentes momentos da rotina no JI. Esta investigação assume uma natureza qualitativa consubstanciada num estudo de caso. De entre as técnicas de recolha de dados utilizadas, é de destacar o recurso a entrevistas semiestruturadas e focalizadas, como forma de promover as vozes das crianças e das profissionais. A investigação, assim como a minha ação assentaram em princípios éticos. As conclusões da investigação remetem para: i) uma visão do brincar enquanto ofício da criança; ii) o reconhecimento de uma pressão social para valorizar e incentivar determinados tipos de aprendizagens, úteis futuramente; iii) a importância de dignificar o papel do/a educador/a e de contribuir para um novo olhar sobre o JI; iv) um olhar das crianças a partir do quadro dos direitos da criança.This report is part of the Curricular Unit Supervised Professional Practice II, inserted in the study plan of the Master's Degree of Pre-School Education. The report highlights the period in which I was integrated as a trainee in a Kindergarten, between October 17th of 2022 and February 13th of 2023, with a group of children aged between 3 and 6 years old and the education team (the Kindergarten teacher and operational assistant). This study comes from the project I developed with the children, in which they manifested their opinions about what children do: play, work and/or do both. Thus, I defined the following goals: i) to know the conceptions of children in Room 3 around the question "Do the children play and/or work?"; ii) to know the professional conceptions of Room 3 (cooperating educator and operational assistant) about the same issue. I also tried to understand how the times-spaces of the Kindergarten influence the projection of moments directed to play and to work and in what degree can the kindergarten teacher's pedagogical practice influence the way children look at the different moments that make up their day in Kindergarten. This investigation assumes a qualitative nature embodied in a case study. Among the choices of the data used, it is worth mentioning the use of semi-structured and focused interviews, as a way of giving voice to both children and professionals. The research, as well as my action, were based on ethical principles. The investigation's conclusions refer to: i) a vision of playing as a child's job; ii) the acknowledgement of a social pressure to value and encourage certain types of learning, useful in the future; iii) the importance of dignifying the role of the kindergarten teacher and contributing to a new look at kindergarten; iv) a vision of children from the framework of children's rights.N/

    Grupo colaborativo mediado pelas Tecnologias de Informação e Comunicação aplicadas à Educação : uma ferramenta potencializadora do desenvolvimento profissional de professores

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    Neste texto colocaremos em discussão, de forma predominante, o referencial teórico que norteia uma pesquisa de doutoramento em andamento acerca do desenvolvimento profissional de professores de História da Rede Municipal de Ensino de Belo Horizonte/Brasil, que vivenciam um processo de formação e consolidação de um grupo colaborativo, mediado pelas tecnologias de informação e comunicação aplicadas à educação - TICE. O processo vivido pelo grupo, na sua criação e consolidação, e o material produzido pelo mesmo constituem-se no objecto central da investigação, tendo em vista compreender as contribuições que esses processos trazem para o desenvolvimento profissional de professores e o papel mediador das TICE. O referencial teórico apoia-se na perspectiva do desenvolvimento profissional de professores, TICE, e, trabalho colaborativo. O percurso metodológico incluiu desde os procedimentos teórico - metodológicos orientadores da criação e funcionamento do grupo, passando pelos procedimentos a serem utilizados para apreender o processo vivido pelo próprio grupo na sua criação e consolidação, até aos procedimentos de colecta do material produzido ao longo do processo por eles vivenciado. Destacaremos também exemplos de colaboração e interacção online do grupo analisado - por meio da ferramenta E-group, como e-mails e reflexões postadas, dando enfoque à potencialidade desta ferramenta.CNPQUniversidade do Minho. Centro de Investigação em Educação (CIEd

    A colaboração on-line como estratégia para o desenvolvimento profissional dos professores

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    Nesta comunicação exploramos o conceito colaboração diferenciando da cooperação. Destacamos como a colaboração on-line pode ser potencializadora do desenvolvimento profissional de professores e apresentamos exemplos desta interacção mediadas pela ferramenta e-group. A partir do conceito de desenvolvimento profissional adoptado por Garcia (1999) - como o conjunto de processos e estratégias que facilitam a reflexão dos professores sobre a sua prática, que contribui para que os professores gerem conhecimento prático, estratégico e sejam capazes de aprender com sua experiência - acreditamos que o grupo de trabalho colaborativo pode ser um espaço desencadeador e propício para que essas reflexões ocorram

    Olive pomace phenolic compounds stability and safety evaluation: From raw material to future ophthalmic applications

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    Funding Information: This project has received funding from the European Union?s Horizon 2020 research and innovation program under the Marie Sk?odowska-Curie Initial Training Network (ITN) ?IT-DED3? (H2020-MSCA-ITN-2017) grant agreement No. 765608. The authors would like to acknowledge the financial support from Fundac?a?o para a Cie?ncia e Tecnologia (FCT) and Portugal 2020 to the Portu-guese Mass Spectrometry Network (Rede Nacional de Espectrometria de Massa RNEM; LISBOA 01 0145 FEDER 402 022125). Soraya Rodriguez Rojo acknowledges the University of Valladolid for her postdoctoral contract. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Nowadays, increasing interest in olive pomace (OP) valorization aims to improve olive’s industry sustainability. Interestingly, several studies propose a high-value application for OP extracts containing its main phenolic compounds, hydroxytyrosol and oleuropein, as therapy for ocular surface diseases. In this work, the stability and accessibility of OP total phenolic and flavonoid content, main representative compounds, and antioxidant activity were assessed under different pretreatment conditions. Among them, lyophilization and supercritical CO2 extraction were found to increase significantly most responses measured in the produced extracts. Two selected extracts (CONV and OPT3) were obtained by different techniques (conventional and pressurized liquid ex-traction); Their aqueous solutions were characterized by HPLC-DAD-MS/MS. Additionally, their safety and stability were evaluated according to EMA requirements towards their approval as ophthalmic products: their genotoxic effect on ocular surface cells and their 6-months storage stability at 4 different temperature/moisture conditions (CPMP/ICH/2736/99), together with pure hydroxy-tyrosol and oleuropein solutions. The concentration of hydroxytyrosol and oleuropein in pure or extract solutions was tracked, and possible degradation products were putatively identified by HPLC-DAD-MS/MS. Hydroxytyrosol and oleuropein had different stability as standard or extract solutions, with oleuropein also showing different degradation profile. All compounds/extracts were safe for ophthalmic use at the concentrations tested.publishersversionpublishe

    Pressurized Liquid Extraction Optimization from Supercritical Defatted Olive Pomace: A Green and Selective Phenolic Extraction Process

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    H2020-MSCA-ITN-2017 01 0145 FEDER 402 022125Olive pomace (OP) is the main by-product of the olive oil industry produced in large quantities. Its valorization as a source of phenolic bioactive compounds is paramount for the sustainable growth of related industries. This work proposes an intensified process to maximize the recovery of phenolic compounds in dry extracts using hydroalcoholic mixtures. Supercritical carbon dioxide defatting pre-treatment was performed. Following this, pressurized liquid extraction was optimized through a circumscribed central composite design. The factors consisted of temperature (65.0-185.0 °C), ethanol percentage (8.0-92.0%), and solid/liquid ratio (0.2-0.8 gOP/mLSOLVENT). Besides the total phenolic content (TPC) and the total flavonoid content (TFC), the major phenolic compounds of OP [hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OL)] were evaluated. Further, decarboxymethyl OL aglycone dialdehyde (3,4-DHPEA-DEDA) was identified by HPLC-DAD-MS/MS as the most abundant polyphenol and was studied for the first time for OP. Different conditions were found to optimize each key compound. In 67% shorter extraction time and 38% less solvent consumption compared to conventional extraction, an increase of 475% for OL, 428% for HT, 194% for TY, 373% for 3,4-DHPEA-DEDA, 89% for TPC, and 158% for TFC was observed. The antioxidant activity by oxygen radical absorbance capacity (ORAC) assay increased 89% (optimal conditions) and correlated with TPC, 3,4-DHPEA-DEDA, and TFC. Thus, an efficient, selective, scalable, and green extraction process was established.publishersversionpublishe

    Pressurized liquid extraction optimization from supercritical defatted olive pomace: a green and selective phenolic extraction process

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    Producción CientíficaOlive pomace (OP) is the main by-product of the olive oil industry produced in large quantities. Its valorization as a source of phenolic bioactive compounds is paramount for the sustainable growth of related industries. This work proposes an intensified process to maximize the recovery of phenolic compounds in dry extracts using hydroalcoholic mixtures. Supercritical carbon dioxide defatting pre-treatment was performed. Following this, pressurized liquid extraction was optimized through a circumscribed central composite design. The factors consisted of temperature (65.0–185.0 °C), ethanol percentage (8.0–92.0%), and solid/liquid ratio (0.2–0.8 gOP/mLSOLVENT). Besides the total phenolic content (TPC) and the total flavonoid content (TFC), the major phenolic compounds of OP [hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OL)] were evaluated. Further, decarboxymethyl OL aglycone dialdehyde (3,4-DHPEA-DEDA) was identified by HPLC-DAD-MS/MS as the most abundant polyphenol and was studied for the first time for OP. Different conditions were found to optimize each key compound. In 67% shorter extraction time and 38% less solvent consumption compared to conventional extraction, an increase of 475% for OL, 428% for HT, 194% for TY, 373% for 3,4-DHPEA-DEDA, 89% for TPC, and 158% for TFC was observed. The antioxidant activity by oxygen radical absorbance capacity (ORAC) assay increased 89% (optimal conditions) and correlated with TPC, 3,4-DHPEA-DEDA, and TFC. Thus, an efficient, selective, scalable, and green extraction process was established.European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Initial Training Network (ITN) “IT-DED3” (H2020-MSCA-ITN-2017) grant agreement No. 765608Fundação para a Ciência e Tecnologia (FCT) and Portugal 2020 to the Portuguese Mass Spectrometry Network (Rede Nacional de Espectrometria de Massa RNEM; LISBOA 01 0145 FEDER 402 022125

    High Inter- and Intra- Diversity of Amino Acid Content and Protein Digestibility Disclosed in Five Cool Season Legume Species with a Growing Market Demand

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    Funding Information: This research was funded by the Fundação Para a Ciência e Tecnologia through R&D Research Unit GREEN-IT-Bioresources for Sustainability (UIDB/04551/2020 and UIDP/04551/2020), Portugal 2020 through the Portuguese Mass Spectrometry Network (LISBOA-01-0145-FEDER-402-022125); and European Union through the project LEGumes for the Agriculture of TOmorrow (LEGATO), FP7 Framework Program (Grant Agreement 613551) and project Co-constructing interactive short and mid-tier food chains to value agrobiodiversity in healthy plant-based food (DIVINFOOD), Horizon 2020 (Grant Agreement 101000383). iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020) and the Associate Laboratories LS4FUTURE (LA/P/0087/2020). Spanish AEI support through the PID2020-114668RB-I00 project is also acknowledged. Publisher Copyright: © 2023 by the authors.Legumes have been sought as alternative protein sources to ensure food security and environmental sustainability. Characterizing their protein content and quality, including in underutilized grain legumes, e.g., grass pea, gives value to the legumes’ underexplored variability. To fill the gap of knowledge in legumes’ protein quality, for the first time, five extensive collections of cool season grain legumes were cropped under the same environmental conditions and further analyzed. Multivariate analysis showed the existent intra- and inter-species variability. The legume species with the highest protein content, grass pea, Lathyrus sativus (LS), was not the one with the overall highest individual amino acids content and in vitro protein digestibility. With these last characteristics lentil, Lens culinaris (LC), was highlighted. The highest average values of arginine (Arg), glutamic acid (Glu), and threonine (Thr) were found in LS and Vicia faba (VF). Cicer arietinum (CA) stood out as the species with the highest values of Thr and methionine (Met). Regarding the in vitro protein digestibility (IVPD), LC, followed by Pisum sativum (PS) and LS, were the legume species with the highest values. Ultimately, this study bought to the fore legume species that are not commonly used in western diets but have high adaptability to the European agricultural systems.publishersversionpublishe
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