3 resultados para Fula negra

em Repositório Digital da UNIVERSIDADE DA MADEIRA - Portugal


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A method for the simultaneous determination of major and minor volatiles composition in different types (dry, medium dry, sweet and medium sweet) of a young Tinta Negra Mole (TNM) monovarietal red wine from 2003 harvest has been validated. Wine samples preparation includes a dichloromethane liquid–liquid extraction followed by concentration under a nitrogen atmosphere. The extracted fraction was analysed by gas chromatography–mass spectrometry and give quantitative information for more than 86 analytes whose concentration range from few μg l−1 to 259.1 mg l−1. The method enables high recovery of volatile compounds in wine good linearity with (r2) values higher than 0.980 and good sensitivity. The limits of detection range from 0.003 to 0.534 mg l−1 and limits of quantification from 0.009 to 1.170 mg l−1. The method allows satisfactory determination of more than 80 compounds in the TNM red wines. These wines are characterized by a high content of higher alcohols, ethyl esters, fatty acids and lactones. The levels of sulphur compounds in Tinta Negra Mole medium sweet wines are very low, but they have the highest concentration of carbonyl compounds. Quantitative analysis of the main odorants followed by the determination of aroma index allow us elucidate the aroma of these varieties. On the basis of their odour description and odour threshold, the most powerful odorants of Tinta Negra Mole wines were tentatively established.

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This study represents the first phytochemical research of phenolic components of Sercial and Tinta Negra Vitis vinifera L. The phenolic profiles of Sercial and Tinta Negra V. vinifera L. grape skins (white and red varieties, respectively) were established using high performance liquid chromatography–diode array detection–electrospray ionisation tandem mass spectrometry (HPLC–DAD–ESI-MSn), at different ripening stages (véraison and maturity). A total of 40 phenolic compounds were identified, which included 3 hydroxybenzoic acids, 8 hydroxycinnamic acids, 4 flavanols, 5 flavanones, 8 flavonols, 4 stilbenes, and 8 anthocyanins. For the white variety, in both ripening stages, hydroxycinnamic acids and flavonols were the main phenolic classes, representing about 80% of the phenolic composition. For red variety, at véraison, hydroxycinnamic acids and flavonols were also the predominant classes (71%), but at maturity, anthocyanins represented 84% of the phenolic composition. As far as we know, 10 compounds were reported for the first time in V. vinifera L. grapes, namely protocatechuic acid-glucoside, p-hydroxybenzoyl glucoside, caftaric acid vanilloyl pentoside, p-coumaric acid-erythroside, naringenin hexose derivate, eriodictyol-glucoside, taxifolin-pentoside, quercetin-glucuronide-glucoside, malylated kaempferol-glucoside, and resveratrol dimer. These novel V. vinifera L. grape components were identified based on their MSn fragmentation profile. This data represents valuable information that may be useful to oenological management and to valorise these varieties as sources of bioactive compounds.

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O presente estudo teve por objetivo verificar se a implementação das ações afirmativas que interferem favoravelmente no processo de aprendizagem e na construção da identidade das crianças e jovens da comunidade Quilombola Onze Negras, podem ser entendidas como instrumento de Inovação Pedagógica. Para isso, inicialmente, embasamos teoricamente este estudo através da compreensão do conceito de ações afirmativas, e realizamos um resgate histórico das lutas empreendidas pelos negros no Brasil, tendo por foco a formação das comunidades quilombolas e a identidade dos negros brasileiros. Na sequência, as incursões à comunidade em estudo, a observação das suas vivências e a realização de inquéritos e entrevistas, dentro e fora da escola, permitiram-nos permear as nossas reflexões acerca deste contexto. Assim, a base metodológica utilizada nesta investigação foi a etnopesquisa crítica de natureza descritivo-exploratória e de abordagem qualitativa, cujos instrumentos utilizados foram a observação participante, a entrevista semi estruturada e o questionário. Os dados recolhidos possibilitaram-nos descrever, interpretar, compreender e analisar as ações cotidianas de nossos atores em seu ambiente natural, e, deste modo, concluir que as ações afirmativas realizadas no seu interior e mais especificamente na escola da comunidade Onze Negras, proporcionando um fortalecimento da identidade negra, podem ser vistas como instrumento de inovação pedagógica.