Escola Superior Agrária
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Browsing Escola Superior Agrária by Sustainable Development Goals (SDG) "10:Reduzir as Desigualdades"
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- Assessing mitochondrial DNA variability in honey bees (Apis mellifera L.) across Europe: inference of introgression and implications for conservationPublication . Tounakti, Sahar; Pinto, M. Alice; Henriques, Dora; Yakoubi, SanaThe Western honey bee (Apis mellifera L.) diversified into 31 subspecies in its widespread native range in Africa, Europe, and part of Asia. Europe is home to 10 of these subspecies, which are grouped into three mitochondrial lineages; the Western European (M), the Eastern European (C), and the African (A). However, due to the increasing trading of commercial strains, typically of C-lineage ancestry, the genetic integrity of several European subspecies and local populations is threatened. This study assesses the maternal diversity patterns in 225 samples originating from 13 European countries by using the highly polymorphic tRNAleu-cox2 intergenic region. Nineteen distinct haplotypes belonging to the M, C, and A lineages were identified, revealing notable regional patterns. In Portugal, A-lineage haplotypes were exclusively identified, suggesting a unique level of conservation within the A. m. iberiensis subspecies. Conversely, in countries such as Finland, Estonia, and Sweden, C-lineage haplotypes predominate, indicating a potential replacement of the native M-lineage subspecies, A. m. mellifera. This study highlights that Ireland maintains a distinct genetic composition predominantly of A. m. mellifera, which together with the Iberian populations, is one of the last M-lineage preserved populations in Europe. These results emphasize the need for nuclear DNA analysis to fully assess genetic introgression and provide a comprehensive baseline for conservation efforts to protect the genetic integrity and diversity of European honey bee populations. Future research should incorporate nuclear DNA markers to complement mtDNA findings, allowing a deeper insight into the degree of introgression and providing a more complete view of the genetic composition of European honey bee populations.
- Characterization and authentication of the honeydew honey from Quercus pyrenaica from Montesinho Natural ParkPublication . Slama, Rania; Falcão, Soraia; Vilas-Boas, MiguelThe commercial interest in honeydew honeys is increasing due to the differentiated nutritional, sensorial and therapeutic characteristics of this honey. In this context, this work aimed to characterize the production of honeydew honey from Quercus pyrenaica oak and identify marker compounds that discriminates the botanical origin of this honey. For that, 42 honey samples were collected in apiaries located in Montesinho Natural Park, Bragança,Portugal, during September of 2021. To achieved the honey characterization, the evaluation of the physicochemical parameters (colour, humidity, acidity, electrical conductivity, diastase index, HMF, proline), as well as, the chemical characterization though mineral analysis (by atomic absorption spectrophotometry), sugarcontent (through high-pressure liquid chromatography with a refraction index detector (HPLC-RI)), proteins (by the Kjeldahl method)) and phenolic compounds (by liquid chromatography coupled to mass spectrometry detector (LC-MS), were performed. The results of the physio-chemical parameters analysis showed that the color ranged from 130 to 150 mm pfund, corresponding to a dark amber color, while the moisture ranged from 14.4 to 18.5 %. The electrical conductivity varied from 0.93 to 1.4 mS.cm-1 with ash levels between 0.45 to 0.74 g/100g. The amount of HMF range from 0 to 24 mg.kg-1, while the diastase varied from 9 to 33 DN. The studied honey samples have pH values ranging between 3.73 and 4.94. The results for free acidity, determined at the equivalence point (pH 7) ranged from 0.19 to 1.026 meq.kg-1 and at the equivalence point (pH 8.3) ranged from 0.325 to 1.28 meq.kg-1. The lactone acidity values of the samples varied between 7.17 and 10.3 meq.kg-1 Finally, the proline content ranged from 0.90 to 8.1 mg.g-1. The analysis of the sugar content showed fructose being the most abundant monosaccharide followed by glucose, ranging from 34 to 36% and 25 to 32%, respectively. The presence of erlose and melezitose was an indication of honeydew. Protein content ranged from 0.42 to 0.96 g/100g honey. Regarding phenolic compounds, 17 phenolic compounds were identified in the honeydew honey samples, where flavonoids were the most abundant compounds, specially chrysin and pinobanksin-5-methyl ether, followed by phenolic acids, specially, caffeic acid and ellagic acid.
- Determinantes sustentáveis da intenção de compra de alimentos biológicos em PortugalPublication . Santiago, Cesário Luís Nobre; Ribeiro, Maria Isabel; Fernandes, AntónioIdentificar fatores sustentáveis com impacto na intenção compra de alimentos biológicos foi o tema escolhido para o presente estudo, devido ao facto, do consumo de alimentos biológicos ser um tema bastante atual, pois a procura destes produtos peculiares tem vindo a aumentar ao longo dos últimos anos em Portugal e a nível mundial. O objetivo genérico desta investigação é contribuir para a produção de conhecimento sobre as atitudes, preferências, hábitos e comportamentos do consumidor português em relação aos alimentos biológicos. A recolha de dados, realizada através da utilização de um questionário (online) decorreu entre 9 de janeiro de 2024 a 6 de fevereiro de 2024. Foi obtida uma amostra constituída por 413 consumidores de nacionalidade portuguesa. A média de idades registada foi 44,7 anos (DP = 11.069 anos), a mediana e a moda foram 47 e 48 anos, respetivamente. A maioria dos inquiridos vivia nos distritos de Bragança (64,0%), Porto (10,4%) e Vila Real (5,1%) e residia em meio urbano (69,2%). Os resultados revelaram que a maioria dos consumidores tinha um nível de conhecimento positivo acerca de alimentos biológicos (83,8%) e identificava o logotipo biológico da União Europeia (68,0%). Os legumes frescos (62,7%) e as frutas frescas (59,6%) eram os produtos mais frequentemente consumidos e eram, por norma, adquiridos diretamente ao produtor (50,5%). Os resultados desta investigação demonstraram que as atitudes, as preocupações ambientais, a consciência da saúde e o preço percebido, para além de terem um impacto positivo, explicavam, em 57,5%, a intenção de compra de produtos biológicos. Ademais, as mulheres registaram maior preocupação ambiental e melhor compreensão relativamente ao preço praticado e associado aos alimentos biológicos. Por fim, quem já experimentou ou consumiu produtos biológicos manifestou maior intenção de compra, assim como maior preocupação ambiental, maior consciência de saúde e melhor compreensão e, consequentemente, atribuía maior importância ao preço percebido, comparativamente aos não consumidores de alimentos biológicos.
- Evaluation of LED photostimulation in the fermentation process of table olives and its impact on physico- chemical and microbiological parametersPublication . Jemai, Eya; Martins, Maria de Fátima Tomé; Crugeira, Pedro; Charfi, IchrakThe consumption of fermented foods has increased in recent years due to their potential health benefits. Table olives are a fermented vegetable product, obtained from the fruits of the olive tree (Olea europaea L.), and are considered an integral part of the Mediterranean diet. Recognized for their sensory, chemical, and nutritional characteristics, they have an autochthonous microflora of yeasts and lactic acid bacteria (LAB), considered a source of probiotics. Among the various methods of obtaining table olives, natural fermentation stands out. Carried out due to the action of microorganisms present in the fruits, it is an artisanal, spontaneous, and very slow process, requiring several months to remove the bitterness of the olives and obtain a quality product. This process depends on several factors, essentially the interactions resulting from the consortium of microorganisms inhabiting this environment. In the last decade, table olive producers have been improving the process by introducing some practices, that promote microbial activity, but the time required to obtain edible olives is still very long. Photostimulation with LED light is a practice that has been explored in several areas, including food processing. Light acts as a promoter of the growth of microorganisms, interfering with bioprocesses. In this sense, this study evaluated the effect of LED photostimulation on the natural fermentation of Negrinha de Freixo black olives, focusing on physicochemical, microbiological, and sensory changes. The fermentation process was monitored under red LED light irradiation (630 ± 10 nm) to assess its impact on pH, titratable acidity, salt content, total phenolic compounds, texture, color, and microbial growth in both olives and brine. Results revealed that LED irradiation significantly influenced the fermentation dynamics, promoting higher microbial activity, particularly in yeasts and lactic acid bacteria (LAB), which accelerated the acidification process and improved microbial counts compared to non-irradiated samples. The irradiated olives retained higher hardness and cohesiveness, indicating better structural integrity. In terms of color, there was an increased lightness, redness, and chroma in irradiated olives, enhancing the visual appeal of the final product. The total phenolic content in irradiated olive samples decreased, suggesting that LED light may help reduce bitterness. Sensory analysis indicated that irradiated olives had improved taste attributes, such as enhanced saltiness and reduced bitterness, along with fewer fermentation defects. These findings suggest that LED photostimulation can optimize the natural fermentation process by enhancing microbial growth, preserving texture, and improving sensory qualities, potentially offering a sustainable approach to reducing fermentation time and enhancing the quality of table olives. The study supports the application of LED light as a promising strategy in the table olive industry, with implications for improving the efficiency and quality of the traditional fermentation process.
- Influência da aplicação de cinza na produção e exportação de nutrientes pelo trevo-encarnado e aveiaPublication . Agostinho, Alberto Domingos; Rodrigues, M.A.; Arrobas, MargaridaOs fertilizantes são substâncias minerais ou orgânicas, que fornecem um ou mais nutrientes ao solo. O uso de fertilizantes tem contribuído para o aumento da produção de alimentos. Não obstante, o uso excessivo pode levar à degradação dos solos e à redução da sua produtividade, podendo comprometer a segurança alimentar. Nos anos recentes, tem havido um esforço na utilização de fertilizantes que possam causar menor dano ambiental e ser um complemento à fertilização convencional. As cinzas têm sido indicadas como alternativas ecológicas na gestão da fertilidade do solo. A cinza é um produto inorgânico obtido durante o processo de combustão, responsável pela maior ou menor sublimação dos componentes químicos, e da adoção da requeima parcial ou total da biomassa vegetal. A cinza possui composição que inclui compostos inorgânicos capazes de proporcionar efeitos benéficos nas plantas, especialmente em solos com maior limitação em nutrientes. O presente trabalho foi realizado em Bragança no período compreendido entre outubro de 2024 e maio de 2025. Teve como objetivo avaliar a influência da aplicação de cinza na produção e exportação de nutrientes pelo trevo-encarnado e aveia. A experiência foi realizada em vasos, ao ar livre. O delineamento experimental foi organizado de forma completamente casualizada com três repetições. Foram incluídos os tratamentos: Cinza; Composto orgânico; Nitrato de amónio; Cinza + Nitrato de amónio; e Testemunha. A cinza foi aplicada à razão de 5 t ha-1. O composto e o nitrato de amónio foram aplicados em doses correspondentes a 60 kg N ha-1. As principais etapas do protocolo experimental foram a preparação dos vasos, a adubação de fundo, a sementeira, a adubação de cobertura, a colheita e preparação das amostras de plantas e de solo e a análise laboratorial. A aplicação das cinzas aumentou os teores de fósforo e potássio no solo para além de elevar a disponibilidade de azoto para as culturas. Na cultura do trevo, aplicação de cinzas resultou em maior rendimento em matéria seca e, consequentemente, maior exportação de macronutrientes em comparação aos tratamentos que receberam nitrato de amónio. Na aveia, maiores rendimentos de matéria seca foram conseguidos com a aplicação de nitrato de amónio, porém as cinzas obtiveram rendimentos mais altos de matéria seca e de exportação de macronutrientes em relação aos tratamentos que receberam composto orgânico e a testemunha. De modo geral, a aplicação de cinza promoveu alterações significativas no pH do solo, elevando-o para valores a volta de 7,1, o que revela eficácia na correção da acidez e impacto positivo na melhoria da reação do solo. O estudo demonstrou que as cinzas podem ser uma alternativa sustentável para a agricultura, pois melhoram a fertilidade do solo e impulsionam a produtividade das culturas.
- Innovative and Sustainable Cultivation of Brassica Eruca vesicaria with Reuse of Wastewater from the Production of Squalius alburnoides by Decoupled AquaponicsPublication . Noamane, Mohamed Wajdi; Dias, Maria Inês; Teixeira, AmílcarThe growth of the world population represents a great challenge for an adequate response to sustainable food production. Unfortunately, the conventional approach to agriculture, adopted in response to this challenge, entails adverse consequences for both the environment and consumer health. To control and/or reduce these consequences, various sustainable plant production techniques have been employed with great success. Aquaponics is a practice that combines hydroponics with aquaculture, distinguishing itself from conventional practices through the more efficient use of water, as the essential nutrients for plant matrix growth come from fish production wastewater. This practice can be established in a coupled or decoupled manner (without a water recirculation system between the hydroponic and aquaculture systems). To meet the specific nutritional needs for sustainable plant production, this project proposes the implementation of a decoupled aquaponics system for the hydroponic production of rocket (Eruca vesicaria L.) using wastewater from the production of a native freshwater fish, Calandino (Squalius alburnoides), in an aquaculture system. The wastewater will be monitored in terms of physicochemical and microbiological parameters, namely, pH, conductivity, temperature, dissolved oxygen concentration and aeration, ammonia and nitrate concentrations, total nitrogen and phosphorus, total coliforms, thermotolerant coliforms, Escherichia coli, and sulfite-reducing Clostridium spores. Additionally, the quality of aquaponics produced rocket will be evaluated through physiological growth characteristics and through its nutritional, chemical, and bioactive profile compared to commercial arugula. The results revealed critical challenges that affected the performance of the aquaponic system, including suboptimal environmental and water quality conditions for both fish and plants. For the aquaculture component, high nitrite, phosphorus, and dissolved oxygen levels, along with high microbial contamination, compromised fish health and nutrient availability. Similarly, the hydroponic component experienced growth challenges due to fluctuating environmental factors such as temperature, humidity, pH, and electrical conductivity, which negatively impacted rocket plant development. Despite these challenges, the aquaponic system showed potential for producing nutrient-dense crops, with the microbial load in fish wastewater underscoring the need for effective water treatment and microbial management. This study emphasizes the importance of rigorous control over key environmental parameters in aquaponics, highlighting the need for optimized systems that balance the specific requirements of both the aquaculture and hydroponic components. By fine-tuning nutrient concentrations, improving water quality management, and implementing better climate control, aquaponics systems can enhance both fish health and plant productivity, offering a sustainable alternative to conventional agriculture. The findings contribute valuable insights into refining aquaponic practices for improved sustainability and productivity in food production systems.