CATAA - Centro de Apoio Tecnológico Agro-Alimentar
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- Metal contaminants in Largemouth bass (Micropterus salmoides) collected in large dams from Tejo River basin and small irrigation damsPublication . Andrade, L.P.; Antunes, Paulo; Paulo, Luísa; Pereira, M.E.; Rodrigues, A.M.Largemouth bass (Micropterus salmoides) is a very important fresh water fish in the Portuguese regional cuisine mainly in the countryside (Central region and north Alentejo). Because there’s no aquaculture industry, all eaten largemouth bass in Portugal are collected in large dams (Basins of Tejo and Guadiana rivers) and small irrigation dams. For decades, the Tejo River received environmental pollutants from non-point and point sources that included intensive agriculture, industrial entities, municipalities and nuclear power plant. The aim of this work was to evaluate some metals (Cd, Cr, Cu, Fe, Hg, Mn, Pb, Zn) present on largemouth bass muscle tissue collected in the section of Tejo River that makes border between Portugal and Spain (TR) (N=9) and collected in three irrigation reservoirs (IR) located near Castelo Branco – Portugal (N=11). Individual were weighted and measured. Age was determined by examining fish scales, and sex determined by gonads observation. Samples for liver, dorsolateral muscle and tail muscle were collected from the right side of the fish. TR average weight 435.14g (±109.15), average length 278.33mm (±23.28), average K condition factor 1.98 (±0.09) and average age 3.11 years (±0,78) were similar (P>0.05) to IR average weight 410.84g (±137.71), average length 278.36mm (±31.13), average K condition factor 1.86 (±0.17) and average age 3.18 years (±0,60). Total mercury was determined in freeze-dried samples by atomic absorption spectrometry with thermal decomposition and gold amalgamation. For the other metal analysis, freeze-dried powders were mineralized with a mixture of HNO3 and H2O2, followed by ICP-OES quantification. Cd and Pb presented concentrations below LOQ (0.025 and 0.15mg.kg-1wet.weight, respectively) for all muscle samples. These values are below legal limits in EU (0.05 and 0.3mg.kg-1wet.weight, respectively). Average Hg levels are below legal limits (0.5mg.kg-1wet.weight) and muscle presented higher levels than liver. These contaminant levels indicate that are no contamination sources in the sampling sites. Cu, Cr, Fe, Mn and Zn are essential micronutrients. Their concentrations were not significantly different between dorsal and tail muscle and were higher in liver (P>0.05), with mean concentrations on muscle being, respectively: TR 0.16 (±0.07),
- Chemical composition of largemouth bass (Micropterus salmoides) filletPublication . Rodrigues, A.M.; Antunes, Paulo; Andrade, L.P.Largemouth bass (Micropterus salmoides) is a freshwater fish originating from the United States of America (USA). This specie was introduced in Portugal (Azores) in the end of the XIX Century. Like in the USA, largemouth bass is one of the most popular freshwater sports fish in Portugal and it is very important in regional cuisine, especially in the countryside. However, there’s a lack of information about the chemical composition of largemouth bass fillet. All eaten largemouth bass in Portugal are caught in large dams and small irrigation dams because there’s no largemouth bass aquaculture industry. The aim of this work was to evaluate the chemical composition of largemouth bass fillet collected in an irrigation reservoir (39º49’27.89’’ N; 07º26’57.92’’ W) located in the Central region of Portugal. Thirteen largemouth bass were collected (average weight 349.85g ±74.23; average length 27.22cm ±1.43; average K condition factor 1.71 ±0.14) and were frozen during seven days. The cutting carcasses and the filet chemical analyses (moisture, protein, fat and ash) took place in the laboratory. In the carcass, the average amounts of viscera, spine, head, skin and filet were, respectively, 8.52% (±1.41), 17.24% (±1.29), 23.06% (±1.85), 7.58% (±0.60) and 43.59% (±1.91). In the filet, the average amounts of moisture, protein, fat and ash were, respectively, 77.67% (±1.07), 18.46% (±0.83), 0.90% (±0.31) and 1.20% (±0.05). We concluded that largemouth bass has a good filet yield with very low fat and high level of protein contents. In fact, as far as we know, these are the first results of carcass and filet characterization of largemouth bass collected in Portugal.
- High total phenol content, antioxidant activity and mineral content in ‘Sweetheart’ cherry peelPublication . Resende, Mafalda; Paulo, Luísa; Antunes, Paulo; Pintado, Cristina MiguelCherry is used for several processed products, resulting in a large volume of subproducts, mainly stones and peel. For evaluation of nutritional potential of some sub products, total phenol content (Folin-Ciocalteu reagent method), antioxidant activity (DPPH method), and calcium, magnesium, sodium, potassium and phosphorus content (ICP-AES) were determined in 'Sweetheart' cherry peel. Results were compared with those of 'Tulameen' raspberry fruit cultivated in the same region. Raspberry is recognised to having a high level of antioxidants, minerals and fibre. Average concentrations of 2793.8 mg gallic acid equivalent kg-1, 3450.9 mg TE kg-1, (Ca) 317.7, (Mg) 267.5, (Na) 9.8, (K) 2196.2, and (P) 407.5 mg kg-1 were found in 'Sweetheart' cherry peel. Regarding raspberries, concentrations of 1411.8 mg gallic acid equivalent kg-1, 2709.5 mg TE kg-1, (Ca) 281.9, (Mg) 227.2, (Na) 1.3, (K) 1646.7, and (P) 76.7 mg kg-1 were found. All nutritional concentrations in peel were significantly higher than in the remaining fruit, showing its potential for nutrition complement production.
- Análise química de mel para garantir conformidade de produtoPublication . Resende, Mafalda; Paulo, Luísa; Nunes, André; Antunes, Paulo
- Caracterização da composição em açúcares do mel da região de Castelo BrancoPublication . Antunes, Paulo; Resende, Mafalda; Anjos, O.Caracterização da composição em açúcares do mel da região de Castelo Branco.
- Convective dehydration processing of peachPublication . Resende, Mafalda; Paulo, Luísa; Nunes, André; Silveira, Ana; Pintado, Cristina Miguel; Antunes, PauloDehydration of peach is an alternative to enhance storage stability, mínimize packaging requirement and reducing post-harvest cost without a sensorial and nutritional quality loss. Preservation of fruits through sun drying techniques is practiced in Cova da Beira (a Portuguese region that has a protected geographical indication for peach), as a homemade process without quality and safety control. The aim of this work was to prepare quality dehydrated products based on a convective drying process with low cost. This process has short drying time and controlled temperature that causes minimal damage to the product without added preservatives or sugar. The samples of ‘Baby Gold’ cultivar (Prunus persica) obtained from local producer were peeled, laminated and immediately dehydrated. Samples were stored in sealed plastic containers at 25°C for subsequent analysis. In the drying process were controlled forced convection air velocity of 1.25 to 1.50 m/s, air temperature between 45 and 75°C and drying time between 7 to 11 hours. During dehydration process temperature and fruit moisture were controlled. pH, acidity, soluble solids content (SSC) and mesophilic aerobic count were performed in fresh and dehydrated fruit. Dehydrated peach were similar to homemade products. Moisture was below 12%, without significant variation of SSC and acidity (on a dry basis). No deleterious effect occurred on peach mesophilic aerobic count, since a slight decrease was registered between fresh and dehydrated fruit.
- Quality parameters, total phenolic content and antioxidant activity in different maturation stages of ‘Sweetheart’ cherryPublication . Paulo, Luísa; Resende, Mafalda; Nunes, André; Pintado, Cristina Miguel; Antunes, PauloThe cherry fruit is considered a nutrient dense food with a relatively low caloric content and a significant amount of important nutrients and bioactive food components. Nowadays there are some investigations regarding on nutritional and antioxidant properties of cherries. The objective of this study was to determine the stages of maturation of Sweetheart cherry from Cova da Beira (Portugal). Physicochemical parameters: firmness, color (L*, a* and b*), soluble solids content (SSC), pH, titratable acidity (TA), total phenolic content (Folin-Ciocalteu reagent method) and antioxidant activity (DPPH method) of ‘Sweetheart’ cherry were evaluated. Three maturation stages were identified and results demonstrated that solid soluble content, phenolic compounds and antioxidant activity increase with ripening stages. For soluble solids content and total phenolic content cherries showed the following average values: 19.9, 20.5 and 22.0 º Brix and 591, 788 and 810 mg galic acid kg-1, respectively. We can consider that this cultivar has an interest in nutritional terms, which may contribute to the enhancement of 'Sweetheart' cherry from the Cova da Beira region. Additionally, these data provide complementary information which can be used to ensure the quality of this regional product, ‘Cereja da Cova da Beira’.
- Composição em proteína, gordura e ácidos gordos de filetes de achigãs (Micropterus salmoides Lacépède, 1802) submetidos a três regimes alimentares diferentesPublication . Andrade, L.P.; Santos, C.; Resende, Mafalda; Antunes, Paulo; Rodrigues, A.M.Composição em proteína, gordura e ácidos gordos de filetes de achigãs (Micropterus salmoides Lacépède, 1802) submetidos a três regimes alimentares diferentes.
- Desidratação osmótica de pêssego com calda açucarada e calda à base de mel.Publication . Morais, Laura Varandas; Nunes, André; Pintado, Cristina Miguel; Paulo, Luísa; Resende, Mafalda; Anjos, O.A desidratação é um processo que consiste na eliminação de água de um produto por evaporação. Com o aumento da produção e sazonalidade de diversos frutos a produção de fruta desidratada pode ser uma alternativa para escoamento dos excedentes. Os produtos alimentares podem ser desidratados por processos baseados na vaporização, sublimação, remoção de água por solventes ou na adição de agentes osmóticos. Nos últimos anos, a desidratação de alimentos tem sido objeto de vários estudos no sentido de produzir alimentos desidratados, que conservem ou melhorem as características sensoriais e valor nutricional, garantindo um custo adequado. Este trabalho teve como objetivo avaliar os parâmetros de qualidade de rodelas de pêssego submetidas a desidratação osmótica utilizando dois tipos de caldas. Numa fase inicial foram realizados vários ensaios a fim de selecionar um programa de secagem adequado, que não proporcionasse alteração significativa da cor da fruta (determinado por colorímetro no sistema CIELAB), fosse adequado do ponto de vista microbiológico e tivesse a preferência dos provadores na avaliação sensorial. O programa de secagem selecionado tem a duração de 12 horas: 30 min até atingir a temperatura de 520C; 10,5 horas à temperatura de 520C; 1 hora para estabilização. De seguida foram testadas 4 caldas: calda açucarada com três concentrações diferentes de frutose (C1: 365 g/L, C2: 490 g/L e C3: 735 g/L) e uma calda à base de mel (diluição de 1:1 m/v); para desidratação osmótica seguida de secagem. Este programa de secagem teve a duração de 10 horas. Para estas 4 amostras foi efetuada uma prova de ordenação tendo a amostra C3 (735 g/L de frutose) obtido a maior pontuação. Para as amostras selecionadas de secagem simples e secagem com pré-tratamento de desidratação osmótica foram efetuadas as seguintes determinações: humidade (PT.LFQ.0135-Método interno); gordura (AOAC 2003.06); proteína (PT.LFQ.0105-Método interno); cinzas (AOAC 934.03); hidratos de carbono (cálculo); valor energético (cálculo); sódio (ICP-OES); sal (cálculo); glucose; frutose; sacarose; maltose; lactose (PT.LFQ.0129-Método interno). Os resultados demonstraram que o produto com pré-tratamento, embora mais apreciados pelos provadores apresenta um teor de açúcares (frutose) superior, inerente ao tratamento e um teor de humidade, gordura e proteína inferior. É de referir, no entanto, que este trabalho deve ser continuado de modo a aferir as melhores condições para a secagem após a desidratação osmótica (especialmente para a calda de mel) dado que os provadores gostaram do sabor da amostra tratada com mel mas pontuaram pior devido à elevada gomosidade que apresentava.
- Composição nutricional do filete de três espécies piscícolas de águas interiores com interesse gastronómicoPublication . Oliveira, Vítor Hugo; Antunes, Paulo; Resende, Mafalda; Andrade, L.P.; Rodrigues, A.M.Composição nutricional do filete de três espécies piscícolas de águas interiores com interesse gastronómico.