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- Discrimination of different monovarietal wines by FTIR-ATRPublication . Antunes, Carlos Alberto Lopes; Carrilho, Cláudia; Peres, Maria de Fátima; Queirós, Rodolfo; Gouveia, Cecília; Teixeira, M.C.C.; Ramos, António Santos; Anjos, O.Discrimination of different monovarietal wines by FTIR-ATR.
- Physicochemical fingerprint of "Pera Rocha do Oeste". A PDO pear native from PortugalPublication . Pedro, Soraia; Coelho, Elisabete; Peres, Maria de Fátima; Machado, Ana; Rodrigues, A.M.; Wessel, Dulcineia F.; Coimbra, Manuel A.; Anjos, O."Pera Rocha do Oeste" is a pear (Pyrus communis L.) variety native from Portugal with a Protected Designation of Origin (PDO). To supply the world market for almost all the year, the fruits are kept under controlled storage. This study aims to identify which classical physicochemical parameters (colour, total soluble solids (TSS), pH, acidity, ripening index, firmness, vitamin C, total phenols, protein, lipids, fibre, ash, other compounds including carbohydrates, and energy) could be fingerprint markers of PDO "Pera Rocha do Oeste". For this purpose, a data set constituting fruits from the same size, harvested from three orchards of the most representative PDO locations and stored in refrigerated conditions for 2 or 5 months at atmospheric conditions or for 5 months under a modified atmosphere, were selected. To validate the fingerprint parameters selected with the first set, an external data set was used with pears from five PDO orchards stored under different refrigerated conditions. Near infrared (NIR) spectroscopy was used as a complementary tool to assess the global variability of the samples. The lightness of the pulp; the b* CIELab coordinate of the pulp and peel; and the pulp TSS, pH, firmness, and total phenols, due to their lower variability, are proposed as fingerprint markers of this pear.
- Grape composition during ripening, in two cultivars and different sites of "Beira Interior" regionPublication . Ramos, António Santos; Valério, Fátima Alexandra; Gouveia, Cecília; Antunes, Carlos Alberto Lopes; Teixeira, M.C.C.; Peres, Maria de Fátima; Anjos, O.Grape composition during ripening, in two cultivars and different sites of "Beira Interior" region
- ATR-FTIR spectroscopy for determination of free acidity, electrical conductivity, ash and total polyphenol content in honeyPublication . Anjos, O.; Peres, Maria de Fátima; Antunes, Paulo; Rodrigues, José CarlosATR-FTIR spectroscopy for determination of free acidity, electrical conductivity, ash and total polyphenol content in honey.
- Implementação e validação de um método por HPLC para determinação de frutose, glucose e sacarose em mel.Publication . Gouveia, Cecília; Vitorino, Conceição; Anjos, O.; Peres, Maria de FátimaO mel é constituído, maioritariamente, por açúcares, água e um grande número de constituintes minoritários. A composição em açúcares influência diversas características do mel, como o sabor, a viscosidade, a cristalização, a conservação, as propriedades térmicas, a higroscopicidade, o valor energético, além das propriedades antibacterianas. Os açúcares representam cerca de 65-85 % dos sólidos totais do mel. A soma de frutose e glucose correspondem no mínimo a 90 % da fração glucídica. O teor destes dois açúcares (que de acordo com o CODEX (2001) deve ser superior a 60 g/100 g) é muito importante para a avaliação da qualidade deste alimento dado que a sua proporção define a possibilidade de cristalização do mel. Por seu turno, a sacarose é um dissacárido que, tal como a frutose e a glucose, assume um papel muito importante na avaliação da qualidade do mel já que, o seu teor máximo se encontra regulamentado em 5 g/100 g, sendo a sua quantificação fundamental para a verificação do cumprimento da legislação (CODEX, 2001). Com o objetivo de criar uma nova técnica analítica que possa juntar-se às que já existem na ESACB, nomeadamente, na prestação de serviços à comunidade e aos trabalhos de investigação, o Laboratório de Instrumentação Analítica, decidiu implementar um método que permitisse determinar em méis os açúcares mais abundantes (frutose e glucose); a sacarose por ter um limite legislado; e a turanose e a maltose para maior caracterização e possível diferenciação dos méis de diferentes regiões. Neste sentido, implementou-se um método por cromatografia líquida de alta pressão (HPLC) com detetor de índice de refração (IR), estudando os parâmetros estatísticos que permitem validar este procedimento. Utilizou-se um cromatógrafo HPLC Agilent 1100, forno de coluna a 30 ºC, uma coluna Purospher STAR NH2 (250 mm x 4,6 mm x 5 !m). A eluição foi isocrática, com eluente acetonitrilo/água 80:20 (v/v), com um fluxo de 1,3 mL/min. A quantificação foi efectuada pelo método do padrão externo. Neste trabalho, estudaram-se os parâmetros de validação mais relevantes já que, se partiu de um método normalizado. Para a sacarose, por existir uma concentração máxima legislada para amostras de mel, avaliaram-se também, a linearidade, repetibilidade, o limite de detecção (LD) e quantificação (LQ) e a sensibilidade.
- Floral monitoring and biophysics parameters as a tool to beekeepers installation decisionPublication . Anjos, O.; Roque, Natália; Lidónio, Eurico; Albuquerque, M.T.D.; Peres, Maria de Fátima; Antunes, I.M.H.R.Beekeeping offers a great development potential, as a source of food, as a nutritional complement and also as raw material provider to several activities. Moreover, biodiversity improvement conservation, incentive for retention of natural habitats and an ideal activity for forest conservation programmes are important factors associated with this activity. Honey is a natural sweet product that is produced in almost all Portuguese Regions. Honeys from certain areas are preferred mainly because of their sensory characteristics, which are related to their floral origin. The pollen and nectar variability influences the honey flavour and determines its commercial quality. The aims of this work are: geographical identification of existing apiaries in the central region of Portugal; identification and quantification of floral sources; characterization of honey (sensory and physico-chemical); construction of thematic maps supporting the new hives installation, predicting the honey characteristics. This methodology has been applied in a Portuguese studied area (Vila Velha de Ródão). A first identification of the apiaries allowed the establishment of the potential zones to future beekeepers installation (Lidónio et al., 2009) (Figure 1). In order to complete the previous information, it is in progress the identification and quantification of species for apiculture interest as well as the honey physical and chemical characterization. Potential apiculture development characterization has been mapped using the following attributes: surrounding area for 200 vegetation units (Forestry zones, agricultural zones and bush zones); slopes warm temperate (warm and very hot); the surrounding area, about 200m, around the water lines and water points; surrounding feeding apiary area (50m diameter); urban admissible legal boundary (100 m diameter for each apiary). It was also considered, the shading maps because of its importance on hive production and bee behaviour. Shading values considered favourable are between 0 and 127. A methodological procedure was developed, aiming the potential beekeeping map construction. Identification of favourable areas, for future beekeepers apiaries installation, will be possible in result of this study. In many Portuguese regions some beekeepers transport their hives, according to the floral sources development in order to reach regions where the production of some species is higher, allowing the improvement of some crop pollinization, for a specific month. Vila Velha de Rodão area, about 10885ha, presents excellent conditions for proper development of beekeeping. It is well documented that the pollen quality and variability, influences the honey flavour and quality (Anjos et al., 2009). The studied region is limited by the major watercourses and their respective valleys and steep slopes. Predominantly those uncultivated land, presents high biodiversity with high beekeeping potential. Some of the most important species present in this region are, Lavandula pedunculata (Miller) Cav., Cistus ladanifer L., Rosmarinus officinalis L., Erica umbellata L., Erica 13th AGILE International Conference on Geographic Information Science 2010 Page 2 of 3 Guimarães, Portugal australis L., Erica lusitanica, Calluna vulgaris (L.) Hull, Retama sphaerocarpa (L.) Boiss., Echium plantagineum L., Genista triacanthos Brot., Quercus rotundifolia Lam, Quercus pyrenaica Willd., Cytisus multiflorus (L'Hér.) Sweet and Cytisus striatus (Hill) Rothm, Arbutus unedo L., Eucalyptus globulus Labill. and Juniperus oxycedrus L. (Almeida, 2004; Carvalhinho, 2004; Monteiro, 2003). In future works, iso-quality mapping, for beekeeping potential characterization, will be concluded, for central Portugal. This will allow the beekeepers installation optimization and support a honey production sustainable management.
- Determinação do teor de polifenois totais for ATR-FTIRPublication . Anjos, O.; Rodriguez, J.C.; Fernandes, A.; Gouveia, Cecília; Peres, Maria de FátimaNeste trabalho foram utilizadas 30 amostras de mel monofloral de diferentes proveniências botânicas, entre as quais se destacam, a urze, o rosmaninho, a laranjeira, o eucalipto, a alfarrobeira e o castanheiro. O teor em fenóis totais foi determinado utilizando o método de Folin-Ciocalteu, usando o ácido gálico como padrão.
- Sensory evaluation of virgin olive oils from organic agriculture and integrated productionPublication . Peres, Maria de Fátima; Gouveia, Cecília; Anjos, O.; Vitorino, Conceição; Henriques, LuísIn the present work four olive groves were selected: two in organic agriculture and two in integrated production. Olives were handpicked at two ripening stages and processed by a low-scale mill with a working capacity of 0.05 tons h-1. Differences between olive oils were evaluated through a sensory quantitative descriptive analysis (QDA) for positive attributes; moreover, some chemical parameters that could be related with bitterness, like phenol content and the specific absorbance at 225 nm (K225), were determined as well. Some analyses were also conducted with an Alpha MOS electronic nose system, FOX 2000.
- Chemical characterization of almond varieties natives from Algarve regionPublication . Carreira, Luís; Neves, Alcinda; Marreiros, António; El-Guendouz, Soukaïna; Ângelo, Luís; Peres, Maria de Fátima; Pedro, Soraia; Anjos, O.; Miguel, Maria GraçaAlmond, Prunus dulcis (Miller) D.A. Webb, syn. Prunus amygdalus Batsch is an important crop due to its fruits with high comercial value. In Portugal, there are traditional orchards in which almond trees grew on marginal soils, rainfed and with consequent low productivity; more recently huge investments in modern orchards with varieties originally from France and Spain such as ‘Ferraganés’, ‘Ferraduel’, ‘Guara’, ‘Marcona’, among others, are replacing the Portuguese varieties1. So, it is important to preserve the traditional almond varieties and the purpose of the present study was to compare the chemical composition of 18 traditional cultivars maintained in the field collection with those commercial cultivars from Europe.
- Aplicación de redes neuronales en la determinación de origen botánico de miel a partir de sus propiedades físico-químicasPublication . Iglesias, Carla; Anjos, O.; Martínez, Javier; Peres, Maria de Fátima; García, Ángela; Taboada, JavierAplicación de redes neuronales en la determinación de origen botánico de miel a partir de sus propiedades físico-químicas.