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- Composição química e propriedades bioativas da noz (Juglans regia L.).Publication . Peres, Maria de Fátima; Gouveia, CecíliaAs nozes são dos frutos secos mais consumidos em todo o mundo. Possuem um elevado valor nutricional, apresentando a relação mais elevada de ácidos gordos ω3/ω6, entre todos os frutos secos. Contêm ainda vários compostos bioativos relacionados com a prevenção de diversas doenças. As evidências científicas atuais permitem a utilização de uma alegacão de saúde específica para a noz designadamente "As nozes contribuem para a melhoria da elasticidade dos vasos sanguíneos".
- Life-cycle greenhouse gas emissions of portuguese olive oilPublication . Figueiredo, Filipa; Coroama, Vlad C.; Ramos, António Santos; Almeida, Arlindo; Ramalhosa, Elsa; Castanheira, Érica; Peres, Maria de Fátima; Carneiro, J.P.; Pereira, José Alberto; Feliciano, Manuel; Gomes, Paulo; Marques, Pedro; Freire, FaustoThe main goal of this paper was to assess the greenhouse gas (GHG) intensity of olive oil production in Portugal. A life-cycle model and inventory were implemented for the entire production process, including a comprehensive analysis of olive cultivation, olive oil extraction, packaging, and distribution. Data originates from five differently-sized Portuguese olive growers and from a total of six olive oil mills, representing the three extraction processes in use: three-phase extraction, two-phase extraction, and traditional pressing. The results show that the GHG intensity lies in the range 1.8-8.2 kg CO2eq/liter and that the main contributors were fertilizers (production and field emissions). Efficient use of fertilizers thus seems to be a key factor for mitigating the GHG intensity of olive oil production.
- Caracterização de azeite virgem coprocessado com citrinosPublication . Cunha, L.; Gouveia, Cecília; Vitorino, Conceição; Peres, Maria de FátimaCaracterização de azeite virgem coprocessado com citrinos.
- 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.
- Integrated production and quality of Galega olive ilPublication . Peres, Maria de Fátima; Luz, J.P.; Fragoso, Preciosa; Gouveia, Cecília; Vitorino, Conceição; Silva, M.C.A.; Henriques, Luís; Coutinho, J.P.; Pintado, Cristina Miguel; Peres, Cidália; Ferreira, ArmandoA study has been carried out to evaluate the influence of integrated olive production on the quality of Galega virgin olive oil. On three consecutive years, olive samples from two different groves in integrated production were taken, and submitted to extraction in industrial mills. The analytical determinations in olive oil were acidity, peroxide index, K232 and K270, sensory analysis, fatty acid composition, total phenol compounds, tocopherols, oxidation stability and organophosphate pesticides. Quality criteria were within the European Union limits for extra virgin olive oil, and the organophosphate pesticides residues were always undetectable.
- Laboratórios Unidades de Apoio Tecnológico : Tecnologia Alimentar, Análise Sensorial, Química e Bioquímica, Instrumentação Analítica.Publication . Peres, Maria de Fátima; Vitorino, Conceição; Gouveia, CecíliaLaboratórios Unidades de Apoio Tecnológico : Tecnologia Alimentar, Análise Sensorial, Química e Bioquímica, Instrumentação Analítica.
- Bioactive compounds of portuguese virgin olive oils discriminate cultivar and ripening stagePublication . Peres, Maria de Fátima; Martins, Luísa; Mourato, Miguel; Vitorino, Conceição; Dias, Suzana FerreiraThe presence of different bioactive compounds in virgin olive oil affects its nutritional, oxidative and sensorial properties. Phenolic compounds are olive endogenous bioactive compounds highly susceptible to degradation. Olive endogenous oxidoreductases, mainly polyphenol oxidases (PPO) and peroxidases (POD), may play an important role on the profile of bioactive compounds in olive oil by promoting oxidation of phenolic compounds. The aim of this study was to evaluate if changes on PPO and POD activities in olive fruits from two Portuguese cultivars (Olea europaea, cv ‘Cobrançosa’ and cv ‘Galega Vulgar’) are related with the composition of their olive oils, especially phenolic compounds. Pattern recognition techniques [principal component analysis (PCA), cluster analysis(CA), and discriminant analysis (DA)] were used for multivariate data analysis. Olive oils characterized by their FA composition were grouped by cultivar. When olive oils were characterized by their phenolic composition, green pigments, and enzymatic activities in fruits, they could be discriminated by olive ripening stage. Along ripening, PPO activity was only detected in the fruit mesocarp of both cultivars and POD activity was mainly detected in the seeds. The POD activity, as well as vanillin and gamma-tocopherol contents in olive oil increased with the ripening index. Conversely, higher PPO activity in fruits at early ripening stages together with higher levels of total phenols, green pigments, betatocopherol, hydroxytyrosol and p-coumaric acid in olive oils were observed. The ripening stage of fruits showed to be a key factor on the amount and profile of bioactive compounds of olive oil.
- Influence of enzymes and technology on virgin olive oil compositionPublication . Peres, Maria de Fátima; Martins, Luísa; Dias, Suzana FerreiraThis work aims at presenting the state-of-the-art about the influence of the activity of olive endogenous enzymes, as well as of the application of adjuvants in olive oil technology, discussing their influence on the composition of virgin olive oil, especially in phenols and volatile compounds.