Browsing by Author "Lopes, Arminda"
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- Avaliação preliminar da diversidade e abundância de artrópodes num pomar de aveleirasPublication . Santos, António; Lopes, Arminda; Martins, Sérgio; Costa, Cristina Amaro DaA biodiversidade funcional é uma mais-valia para os sistemas agrícolas, em particular pelo papel que desempenha na promoção de vários serviços do ecossistema, designadamente a limitação natural dos inimigos das culturas. A biodiversidade de artrópodes associados à cultura da aveleira em Portugal, em particular no que se refere à fauna auxiliar, é pouco conhecida, resumindo-se a listagens das pragas mais relevantes. Neste sentido, com o objetivo de contribuir para a conservação e promoção da biodiversidade funcional, na cultura da aveleira, importa conhecer a diversidade e abundância de artrópodes deste agroecossistema. O trabalho foi desenvolvido no pomar de aveleiras da Estação Agrária de Viseu, conduzido em modo de produção biológico. Procedeu-se à recolha de artrópodes, quinzenalmente, entre maio e agosto de 2018, através da técnica das pancadas, após o que foram triados em laboratório e separados por ordens, morfotipos e tipos funcionais (predadores, parasitóides, fitófagos, detritívoros e indiferentes). Capturaram-se 1557 artrópodes pertencentes a 9 ordens da classe Insecta (88% dos exemplares) e à classe Arachnida (ordem: Araneae). Relativamente à classe Insecta, as ordens mais abundantes foram: Hemiptera – subordem Heteroptera, (Anthocoridae e Miridae), Coleoptera (maior número de morfotipos, em particular da família Coccinelidae) e, ainda, Hymenoptera, Dermaptera e Neuroptera.
- Chemical and Physical Properties of Some Hazelnut Varieties Grown in PortugalPublication . Ferrão, Ana Cristina; Guiné, Raquel P. F.; Ramalhosa, Elsa; Lopes, Arminda; Rodrigues, Cláudia Filipa; Martins, Hugo; Gonçalves, Roberto; Correia, PaulaHazelnuts are one of the most appreciated nuts worldwide due to their unique organoleptic and nutritional characteristics. The present work intended to analyse several physical and chemical properties of different hazelnut varieties grown in Portugal, namely Tonda de Giffoni, Grada de Viseu, Segorbe, Longa de Espanha, Butler, Gunslebert, and Negreta. In general, the results revealed statistically significant differences between the varieties under study. The Gunslebert had more elongated hazelnuts and with heavier shelled fruits, while the kernels of the Grada de Viseu revealed to be heavier. Grada de Viseu was harder in the shell, Gunslebert had a harder core, and Segorbe was more resistant to fracture. Fat was the more representative component for all varieties and in some cases the values of moisture and water activity were over the recommended amount (≥0.62). Tonda de Giffoni was the variety with the highest induction time, indicating the highest oxidation stability. Moreover, discriminant analysis revealed that the variables more important to distinguish the varieties were protein (λ = 0.007) and water activity (λ = 0.010). The results of this study help to better understand the differences between some hazelnut varieties that are cultivated in Portugal, which gives important hints for all players in the hazelnut sector.
- Comparação de propriedades de maçãs produzidas em modo biológico e convencional.Publication . Guiné, Raquel; Lopes, Arminda; Correia, Ana Cristina; Jordão, António; Ferreira, DulcineiaNão disponível
- Composition of apples from regional varieties in different harvest years.Publication . Guiné, Raquel; Sousa, Rute; Alves, Ana; Figueiredo, Catarina; Fonseca, S; Soares, s; Correia, Ana Cristina; Jordão, António; Lopes, Arminda; Ferreira, DulcineiaIn the present work apples of regional varieties originating from Portugal were studied in terms of some chemical properties along three consecutive harvest years. It was possible to conclude that these regional varieties of apples were generally sweeter and contained more minerals than other varieties described in literature. The data obtained revealed that the content in acidity, protein and minerals depends on the apple variety. The acidity content varied much along the 2004, 2005 and 2006 harvests. For total sugar,or protein contents the variations observed were comparatively smaller. In the 2004 and 2005 harvests the sugar and protein contents do not differ so much differing more in the 2006 harvest. In respect to mineral content, the 2004 harvest registered the higher differences, and this was also the year when the apples were considerably riper.
- Evaluation of morphological and physical characteristics of hazelnut varietiesPublication . Lopes, Arminda; Matos, Alexandre; Guiné, RaquelIn this study 15 hazelnut varieties existing in a collection of Viseu Agricultural Station were evaluated. The nuts were studied in respect of their morphological characteristics, such as fruit and kernel weight, index of compression and of shape and shell thickness. The study was complemented with analysis of physical properties such as colour and texture, and the determination of moisture content and water activity, given the importance that these parameters take in the conservation capacity of the fruits. All experiments followed standard methods, being also used the following equipment: texturometer, colorimeter and hygrometer. The results obtained allowed to know the expectable ranges for each color parameters in the shell, film and kernels: L*, a*, b* chroma and hue, having been found statistically significant differences among the cultivars studied. As regards the textural parameters evaluated by crust crushing and crumb cutting tests (hardness, friability and resilience) there were also significant differences. Evaluation of moisture was of great importance because confirmed that the solar drying, used to extract the excess of moisture from the fruits, was sufficient to reach low values, between 1.66% and 4.52%, being so a guarantee of preservation.
- Phenolic, dietetic fibre and sensorial analyses of apples from regional varieties produced in conventional and biological mode.Publication . Guiné, Raquel; Sousa, Rute; Alves, Ana; Teixeira, Luís; Figueiredo, Catarina; Fonseca, S; Soares, S; Sousa, I; Almeida, P; Coreria, Ana Cristina; Jordão, António; Lopes, Arminda; Ferreira, DulcineiaIn the present work apples from eleven regional varieties originating from Portugal were studied in terms of their content in phenolic compounds and dietetic fibres (soluble and insoluble). In some cases, apples from two different production modes were analysed: conventional and biological. Some of the most commercialized apples in Portugal were also studied for comparison purposes. In addition, a sensorial evaluation of some of the varieties was performed. From the present work was possible to conclude that the regional varieties studied contain higher amounts of dietetic fibre than those of commercial varieties and other fruits. With respect to the content in total phenolic compounds, the apples of regional varieties showed values clearly higher than those quantified in commercial varieties, and being concentrated mainly on the peel, then on the seeds, and finally on the pulp. From the sensorial analyses was possible to infer that the regional varieties which were more appreciated were Bravo de Esmolfe and Camoesa de Alcongosta
- Physicochemical and Microbiological Properties of Hazelnuts from Three Varieties Cultivated in PortugalPublication . Ferrão, Ana Cristina; Guiné, Raquel; Silva, Marco; Lopes, Arminda; Correia, PaulaHazelnut is an important crop worldwide, and the characteristics of the fruits are quite variable according to a number of factors, including variety and cultivation conditions, which in turn can vary according to harvest year. This study aimed to investigate some physical and chemical characteristics of three hazelnut varieties grown in Portugal (Grada de Viseu, Tonda di Giffoni and Butler) along two different harvesting years (2021 and 2022). Also, the microbial quality was investigated for its relevance to the conservation of the fruits. The physical properties evaluated were biometric characteristics and colour, the chemical components analysed were moisture, lipids, protein, ash and fibre, and the microbial properties investigated were the microorganisms, moulds and yeasts. The results showed that, generically, statistically significant differences were found between the three varieties under study on several properties investigated. The kernel was confirmed as the lighter part of all hazelnuts, and when comparing between varieties, Tonda di Giffoni presented the lighter fruits in both harvesting years. With respect to weight, the Tonda di Giffoni variety was the lightest in both harvest years. Moisture content was observed to be higher than the recommended limits for two of the samples (Grada de Viseu in 2021: 6.01 ± 0.26 g/100 g and Butler in 2022: 6.02 ± 0.37 g/100 g), although the difference was marginal given that the recommended limit is 6%. Not surprisingly, lipids were the major chemical component, ranging from 66.46 ± 1.67 to 70.14 ± 1.75 g/100 g in 2021 and from 64.38 ± 1.67 to 77.77 g/100 g in 2022. It was further observed that the three varieties presented a satisfactory microbiological quality. Finally, applying factor analysis with principal components and Varimax rotation, a solution that explains 92.8% of the variance was obtained. This study provided information that is relevant for the characterisation and evaluation of variability according to the year of hazelnuts of three varieties cultivated in Portugal.
- Properties of regional portuguese apple cultivars produced in conventional and organic modes.Publication . Guiné, Raquel; Andrade, Sérgio; Sousa, Rute; Alves, Ana; Teixeira, Luís; Figueredo, Catarina; Fonseca, S; Soares, S; Correia, Ana Cristina; Jordão, António; Lopes, Arminda; Ferreira, DulcineiaThe present work aimed at studying apples from regional varieties originating from Portugal in terms of physical and chemical attributes. The apples analysed were produced in two different production modes: conventional and biological, to verify in which extent this variable influences the results. The data obtained enabled us to conclude that the chemical properties: moisture content, total and reducing sugars, protein and ash, were influenced by the production mode in different ways, depending on the variety. As to the textural properties estimated, the results showed that the variety Lila is the one that presents the higher similarity when comparing the conventional with the biological modes of production. Furthermore, it was possible to observe that the production mode does not significantly influence the fibre contents in the varieties of apples analysed.