Browsing by Author "Ferreira Wessel, Dulcineia"
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- Analysis of the alterations in the color of pears dried under different systems.Publication . Guiné, Raquel; Lima, Maria João; Barroca, Maria João; Ferreira Wessel, DulcineiaIn Portugal, pears are traditionally dried by a direct sun-exposure method. However, because of the disadvantages associated with this procedure, alternative dryings are being tested. The objectives of this study were to evaluate how drying influences the color of pears, and to compare the products dried through different systems, to evaluate which one allows obtaining a product as much as possible with the same color of the traditional pears. From the results obtained was possible to see that dryings in systems with exposure to the sun (through glass) allow obtaining products that do not differ much from the traditional dried pears.
- Antioxidant Properties of Bee Products of Plant- Origin Part 2. Propolis and PollenPublication . Fernandes, Pedro; Ferreira, Sónia; Fonte, Alice; Ferreira Wessel, Dulcineia; Cardoso, SusanaOver the last years, the hive products such as propolis and pollen have been highlighted due to their potential health benefits, including antioxidant abilities that have been correlated with their content in phenolic compounds. Regardless of the several factors that may affect propolis and pollen antioxidant activity, these products have been shown to possess, either through the use of in vitro or in vivo models, important features concerning the modulation of cellular oxidative stress caused by environmental factors (e.g. UV-light), metals, pesticides and other xenobiotics. This modulatory effect focus not only on the capture of radicals that these elements might eventually generate, but also by the activation of cellular antioxidant mechanisms such as enzymatic antioxidants or by modifying gene expression patterns. Although the mechanisms behind these responses are not fully known, it has been showed that caffeic acid phenethyl ester, pinocembrin and chrisin are some of the compounds responsible for some of these responses. Taking into account the gathered results, propolis and pollen can be viewed as potential agents in the re-stabilization of cellular oxidative imbalance and in the prevention of oxidative stress related diseases.
- Avaliação de impacte ambiental da gestão de resíduos da produção de uma bancada com base na abordagem de ACVPublication . Silva, Luiza; Ferreira Silva, Maria Elisabete; Brás, Isabel; Domingos, Idalina; Ferreira Wessel, Dulcineia; Ferreira, JoséIntroduction: Consumerism has led to an increase in environmental problems, and for this reason, sustainable solutions must be the priority when designing new products or services. Life Cycle Assessment (LCA) is one of the most important analytical tools available for choosing the best decision when it comes to sustainability. Objective: The focus of this study was to apply an LCA to the management of wastes from a kitchen/bathroom countertop production. The waste management scenarios studied were landfill (current practice) and waste recycling. The panel consists of a ceramic layer on a lamellar panel substrate, formed by glassliner and PVC, which is intended to be resistant to water, scratches and impacts. The residues generated from the panel production are glassliner and PVC plastics and ceramics. Methods: The LCA methodology was followed and the EPD 2018 method available in the SimaPro software was chosen to quantify the environmental impacts of waste management. The environmental impact categories studied were eutrophication, global warming, photochemical oxidation, ozone layer depletion, abiotic depletion and acidification. Results: The results showed that the two plastic wastes are the main contributors to acidification, eutrophication and global warming. However, for photochemical oxidation and water scarcity, the ceramic component residue is the main contributor. Comparing the two scenarios, waste recycling reduces the impacts in all environmental impact categories, in comparison with landfill. Conclusion: Recycling the residues from the production of panels brings improvements in environmental impacts in all categories analyzed.
- Caracterização da Pêra Passa de ViseuPublication . Ferreira Wessel, Dulcineia; Costa, Cristina Amaro Da; Correia, Paula; Guiné, RaquelA pêra passa de Viseu surge como um produto agrícola regional, que resulta de um processo tecnológico artesanal e que reúne características organolépticas ímpares. A produção de pêra passa de Viseu tem decrescido acentuadamente nos últimos anos, provavelmente devido aos elevados custos de produção, à deficiente promoção do produto e ao desconhecimento das suas qualidades. No sentido de proteger e valorizar a qualidade deste produto agro-alimentar tradicional da Beira Alta iniciou-se um trabalho que tem por objectivo caracterizar em termos da produção, tecnologia e propriedades físico-químicas a pêra passa de Viseu. Neste contexto, vão ser apresentados, numa primeira fase, dados sobre a produção e caracterização química da pêra passa de Viseu.
- Caracterização da Pêra Passa de Viseu.Publication . Ferreira Wessel, Dulcineia; Costa, Cristina Amaro Da; Correia, Paula; Guiné, RaquelNão disponível
- A Cradle-to-Grave Life Cycle Assessment Study on a New Countertop MaterialPublication . Silva, Luiza; Silva, Maria; Brás, Isabel; Domingos, Idalina; Ferreira Wessel, Dulcineia; Ferreira, JoséThe life cycle of furniture products has been decreased in the last years as a consequence of the continuous improvement of people’s housing conditions. This behavior increases the waste amount in an urban area. The focus of this study was developing a Life Cycle Assessment (LCA) (cradle-to-grave) of a new countertop product. Two scenarios for countertop waste management were proposed, one considering landfilling and another considering recycling. The functional unit chosen was 1 m2 of finished panel (countertop) and the boundary system involved the study of raw materials, product packaging, the panel production process, the installation process, the panel use, and its end of life. The chosen method for impact assessment was EPD (2018) available in the SimaPro PhD software. The results showed that recycling has a positive effect on the environmental impacts, with the variation ranging from 0.3% on Abiotic Depletion (FF) to 15.9% on Eutrophication. A comparison between the product studied and products with similar functions was also conducted and although this product was not the worst performer, it has a lot of room for improvement.
- Effects of the Addition of Different Additives before Mechanical Separation of Pig Slurry on Composition and Gaseous EmissionsPublication . Pereira, José L.S.; Perdigão, Adelaide; Tavares, Ana; Silva, Maria E. F.; Brás, Isabel; Ferreira Wessel, DulcineiaThe treatment of animal slurry is used to improve management on a farm scale. The aim of this laboratory study was to assess the effects of the addition of the additives biochar, alum and clinoptilolite before the mechanical separation of whole pig slurry (WS) on the characteristics and emission of NH3 , N2O, CO2 and CH4 from solid (SF) and liquid fractions (LF). The additives were mixed with WS (5% w/w), followed by separation, in a total of 12 treatments with 3 replicates, including the controls and WS with additives. Gaseous emissions were measured for 30 d by a photoacoustic multigas monitor, and initial characteristics of the slurries were assessed. The results indicated that the separation of the WS modified the initial physicochemical characteristics and increased the GWP emissions of the SF and LF, but not the NH3 losses. However, the addition of additives before separation increased the nutrient value and reduced the GWP emissions from the SF and LF. Additionally, just the additive alum was effective in the reduction of E. coli. The additives led to significant reductions in NH3 and N2O emissions, with higher reductions in NH3 losses for alum (51% for NH3 ) and similar N2O losses for all additives (70% for N2O) observed, whereas the CO2 and CH4 emissions were reduced by biochar (25% for CO2 and 50% for CH4 ) and alum (33% for CO2 and 30% for CH4 ) but not by clinoptilolite. Although the additives had a positive effect on slurry management, it can be concluded that the addition of alum before mechanical separation has the potential to be the best mitigation measure because it improves the nutrient content and sanitation and decreases gaseous losses from slurry management.
- Greenhouse Gas Emissions and Ryegrass Yield after Application of Solid-Liquid Pig Slurry and Biochar to an Agricultural SoilPublication . Pereira, José Luís da Silva; Perdigão, Adelaide; Bonifácio, Gabriel; Figueiredo, Vitor; Marques, Francisco; Trindade, Henrique; Ferreira Wessel, DulcineiaBackground: The application of animal slurry to the soil improves its quality, as manure contains many nutrients for plants. However, this could negatively impact the environment. Objective: This field study investigated the effects of the addition of biochar after the mechanical separation of Whole pig Slurry (WS) into Solid (SF) and Liquid Fractions (LF) on Greenhouse Gases (GHG) emissions (N2O, CO2, and CH4) and ryegrass (Lolium multiflorum Lam. cv magnum) yield. Methods: Biochar (1.0 kg m-2) was applied in plots alone or together with each of the three slurries (80 kg N ha-1) in a total of eight treatments with three replications, including just soil with and without biochar as controls. Soil properties, Greenhouse Gas (GHG) fluxes, and yield were measured during theautumn/winter growing season. Results: The results showed that the addition of biochar to these three slurries significantly increased the soil pH and showed no impact on the other physicochemical properties. The GHG emissions were not significantly different between treatments with and without biochar. The N use efficiency increased significantly in SF > WS > LF, whereas no differences were observed among these three slurries with and without biochar. Conclusion: It can be concluded that the addition of biochar combined with WS or SF/LF to sandy-loam soil appears to have no impact on GHG emissions and ryegrass yield during the autumn/winter season. Overall, this finding suggests that amounts higher than 1.0 kg m-2 of biochar combined with SF may need to be applied to soil to reduce GHG emissions and nitrate leaching and increase N use efficiency and crop yield
- Influence of cardoon flower (cynara cardunculus L.) and flock lactation stage in PDO Serra da Estrela cheesePublication . Fogeiro, Élia; Barracosa, Paulo; Oliveira, Jorge; Ferreira Wessel, DulcineiaSerra da Estrela (SE) cheese is one of the most appreciated Portuguese cheeses, being produced only from raw ewe's milk, cardoon flower and salt. Cardoon takes part in two important processes in cheese production-coagulation and proteolysis-contributing to its unique features. Furthermore, milk chemical characteristics change during the milking season, being another factor that account for the high variability of cheese attributes. Therefore, the purpose of this work is to study the influence of cardoon flower (commercial, 6 M and 3 M) and flock lactation stage (November 2018, February and April 2019) in the final characteristics of SE cheese. The parameters analysed were moisture, protein, fat and salt contents, texture and colour. Results showed that flock lactation stage has the highest influence in all the studied characteristics, corresponding the early stages of lactation to the most protein-rich and low-fat cheeses. Cardoon flower affects mainly fat and rind colour. This study allows us to conclude that seasonal changes in ewe's milk have a considerable impact in cheese attributes, and that although cardoon type had a more restrained effect, when used with expertise it may help adjust cheese sensory characteristics in order to obtain a final product that matches consumer acceptability requirements.
- Influence of Different Agro-Food Waste on Ammonia and Greenhouse Gas Emissions during CompostingPublication . Pereira, José; Costa, Telma; Figueiredo, Vítor; Marques, Francisco; Perdigão, Adelaide; Brás, Isabel; Ferreira Silva, Maria Elisabete; Ferreira Wessel, DulcineiaComposting is one of the best organic waste management techniques, with zero waste; however, it generates environmental impacts. The objective of this study was to evaluate the emission of NH3, N2O, CO2, and CH4 from the composting of olive, elderberry, and grape agro-food waste. The experiment was carried out using reactors receiving straw as control and three treatments receiving mixtures of straw and olive, elderberry, or grape wastes. The gas emissions were measured for 150 days, and the composition of the mixtures and composts was determined. The results showed NH3 and CH4 emissions were reduced by 48% and 29% by the Olive and Elderberry treatments, while only NH3 loss was reduced by 24% by the Grape treatment. Nitrous oxide, CO2, and GWP emissions were reduced by 46%, 32%, and 34% by the Olive treatment, while these losses were not reduced by the Elderberry or Grape treatments. It can be concluded olive waste can effectively reduce NH3 and GWP, while elderberry and grape wastes are also effective in reducing NH3, but not GWP. Thus, the addition of agro-food waste appears to be a promising mitigation strategy to reduce gaseous losses from the composting process.