Freitas, Patrícia; Dias, L.G.; Peres, António M.; Castro, Luís M.; Veloso, Ana C.A.
The electrochemical reduction of 2,4,6-trichloroanisole (TCA), a chlorinated arene with electron-donating substituents, was evaluated by cyclic voltammetry (CV). TCA is a major concern for the winery industry since it is related with “cork taint”, a wine defect. The results obtained showed that CV could be used to detect and quantify TCA in standard solutions. Linear relationships could be set between the current amplitude and TCA concentrations (R>0.990) with detection and quantification limits of 0.08 and 0.26 ppm. Although, these preliminary limits are higher than the human sensory threshold (5 ppt in wine), the simplicity of the methodology confers this study...
Cardoso, Susana M.; Falcão, Soraia; Peres, António M.; Pereira, Olívia R.; Domingues, M.R.M.
Fernandes, Conceição; Monteiro, Sandra Mariza; Fontaínhas-Fernandes, A.; Salgado, Maria Antónia
The Esmoriz/Paramos coastal lagoon, is a habitat of ecological
importance due to the presence of unique animal and plant species. During the past few years its immersed area has been gradually
reduced due to effluent discharges and siltation. The major
contaminants in the lagoon are derived from a multitude of nonpoint
sources associated with urbanization and industrial activities
within the watershed. Heavy metals are probably a class of
pollutants contributing to the observed decline of fish species. The
metal content in the water and sediments in the lagoon were
investigated as well as gill metal bioaccumulation and gill
histopathological changes of the grey leaping mullet, Mugil saliens.
Fernandes, Conceição; Fontaínhas-Fernandes, A.; Peixoto, Francisco P.; Salgado, Maria Antónia
The Esmoriz-Paramos coastal lagoon represents an ecosystem of great physical and ecological
significance. However, as a result of industrial, agricultural and antropogenic activities this habitat
has been progressively degrading over the last decades. The heavy metal contamination is an
important factor to the decline of sediments quality and may adversely affect fish health. In the
present work the leaping grey mullet Liza saliens was studied because it is the dominant endemic
species in the lagoon. It is a filter feeder and also being a detritus-mud feeder, it is therefore
exposed to contaminated sediments.
Machado, Carla; Fernandes, Conceição; Pereira, Joel; Poças, Maria de Fátima
This paper presents an exercise to simulate exposure of Portuguese consumers to benzophenone, a photoinitiator used in packaging printing inks. The simulation model combines experimental data of benzophenone concentration actually found in packages collected from the market and food consumption and packaging usage data obtained from a database. The model follows a probabilistic approach: the distribution of occurrence data was combines with food consumption data in a probabilistic simulation with the Monte Carlo sampling method. Exposure values found indicate that benzophenone levels of exposure are of no concern healthwise according to the tolerable daily intake defined by EFSA.
Almeida, Arlindo; Peça, José; Pinheiro, Anacleto; Dias, António; Santos, Luís S.S. dos; Reynolds, Domingos; Lopes, João
Three mechanical harvesting systems for olives have been tested in field trials in the two main Portuguese regions of olive production: Trás-os-Montes and Alentejo. These tests took place in traditional olive orchards with 100 to 150 trees per hectare.
In the three systems, olives were harvested with the same trunk shaker and were collected manually (system I); with a tractor mounted rolling canvas (system II); with an inverted umbrella (system III).
Results are revealed in terms of working rates. The main factors that influence the systems performance are discussed.
Gomes, Teresa; Barradas, Carla; Dias, Teresa; Andrade, João Verdial; Morais, Jorge Sá; Ramalhosa, Elsa; Estevinho, Leticia M.
Mead production represents a possible economic alternative to honey producers that intend to obtain honey products with surplus value. From that the present work aims to study the influence of using different production scales on the quality of the final mead obtained and on the process performance. Increasing the production scale almost ten times (1.5 to 20 L), some differences were observed. Maximum specific growth rates equal to 0.045 and 0.038 h-1 were obtained for fermentations carried out at 1.5 and 20 L, respectively. The time course of glucose and glycerol were similar for both production scales. Nevertheless, slight differences...
Ramalhosa, Elsa; Lamas, Hugo; Pereira, J.A.; Morais, A.M.M.B.
Chestnut is a fruit of great importance in Portugal, being generally sold fresh or frozen. Alternative products may be obtained by hot air drying.
The present work is on the dehydration behavior of Portuguese ‘Longal’ chestnut, that is the most used in industry. Different models for representing the variations of water content and drying rate along time were tested successfully. As expected, higher temperatures correspond to faster drying processes. The apparent diffusivity was predicted by Fick’s second law equation, and it ranged from 1.25x10-11 m2/s, at 20ºC, to 8.42x10-10 m2/s, at 100ºC.
Rodrigues, M.A.; Arrobas, Margarida
In this study, the variability in olive yields per individual tree within homogeneous plots of trees was analyzed as well as the variability on the mean olive yields of each plot of trees over a period of years. Data supporting this work were recorded from two dry farmed olive orchards located in Bragança and Mirandela, NE Portugal. From each olive orchard data were collected separately from two different plots, where the ground was managed by conventional tillage or by using post-emergence herbicides.
Guerra, Luís; Pereira, Carla; Rodrigues, M.A.; Andrade, P.B.; Gonçalves, Rui; Seabra, R.M.; Valentão, P.
Several species of the Rumex (Polygonaceae) genus have been used in traditional medicine, although their high oxalic acid content has been implicated in oxalic intoxication, mainly la children. Rumex induratus Boiss & Reuter is an endemic Liberian herb that prefers rocky habitats of the thermo Mediterranean region.
Rodrigues, M.A.; Coutinho, João; Martins, Fernando
The study was conducted over a 4 year period with the purpose of measuring N mineralization using an in situ incubation technique, following the application of farmyard manure, poultry manure or municipal solid waste. The results varied from –10 % (net immobilization) to +28 % (net mineralization) in relation to the total organic N applied. N fluxes were assessed through plant N analysis during the growing season and through determination of potato tuber dry weight (TDW), N uptake by tubers and the apparent N recovery (ANR) of added N at harvest. Organic material applications slightly increased TDW above the control...