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Influence of orchards fertilization management and post-harvest storage time on Malus domestica cv. ‘Gala’ fruit volatiles and quality parameters Texto completo
2025 | 2026
Figueiredo, Ana Cristina | da Silva, Anabela Bernardes | Tavares, Cláudia | Pastaneira, Mafalda | Melo, Juliana | Ferro Rodrigues, Carolina | Machado, Alexandra | Antunes, Marília | Cruz, Cristina | da Silva, Jorge Marques | Matos, Ana Rita | Pedro, Luís | Barroso, José | Almeida, Patrícia | Maurício, Anabela | Rosa, Cristina | Faria, João | de Sousa, Miguel L. | Santos, Ricardo | Raimundo, Délio | Oliveira, Cristina
“Maçã de Alcobaça” is a type of apple from the West coast of Portugal with Protected Geographical Indication (PGI). This study evaluated the influence of the orchard’s fertilization and post-harvest storage time on the quality of “Maçã de Alcobaça”, ‘Gala’ cultivar. Five orchards were studied for four years, using three fertilization treatments [Standard, twice Standard (2xStandard) and twice Standard including organic matter (2xStandard_OM)]. The fruits’ volatile profile, emanation index, and quality parameters were determined in apples after harvest time (T0), three- (T3) and five months (T5) after storage. At T0, the intact apples volatiles were dominated by trans,trans-α-farnesene (48–79 %). trans,trans-α-Farnesene emanation index was larger in T0 apples independently of the orchard and fertilization treatment, and showed an accentuated decrease from T0 to T5. Fruits quality at T0 and T5, showed significant differences per orchard, but their average weight, TSS, and firmness, were not significantly altered with fertilization treatment. Storage did not significantly affect the fruits weight, but TSS and firmness always decreased regardless of the orchard or fertilization treatment. Among other things, the observed variations among orchards after fertilization treatments may relate to the cultural practices of each orchard as well as the fact that their ages and rootstocks varied. | info:eu-repo/semantics/acceptedVersion
Mostrar más [+] Menos [-]Qualidade e Segurança Alimentar de covilhetes: Impacto do teor e tipo de margarina utilizada na massa folhada nas características organoléticas Texto completo
2023 | 2026 | 2024
Moura, Joana Cristina Nóbrega | Saraiva, Cristina | Fontes, Maria da Conceição
Os produtos de pastelaria são apreciados globalmente. Desta forma, é importante estudar as características sensoriais e físico-químicas dos mesmos de modo a alcançar as exigências e preferências por parte do consumidor. Os ingredientes utilizados neste tipo de iguarias podem apresentar perigos de origem física, química e ainda, perigos de origem biológica que são os principais responsáveis por doenças de origem alimentar, levantando questões a nível da segurança alimentar dos produtos. O presente trabalho teve como objetivo a redução do teor de margarina utilizada no produto de pastelaria salgada Covilhete, através de vários estudos nutricionais, físicoquímicos, microbiológicos e sensoriais. Com este propósito, numa primeira fase do trabalho foram recolhidos 54 covilhetes (6 lotes x 3 tempos x 3 amostras). As amostras foram sujeitas a análises microbiológicas. Na segunda fase do trabalho, foram recolhidos 24 covilhetes (3 lotes x 2 amostras x 4 condições) após cozimento e, posteriormente foram determinados parâmetros físicoquímicos, nutricionais e microbiológicos em amostras de covilhete com margarinas diferentes e com uma redução de 20% de cada uma delas na sua formulação. Para além disso, foi também avaliado o perfil de ácidos gordos onde foi determinado o tempo de retenção dos ácidos gordos presentes e, os respetivos ácidos gordos. Por último, foi realizada uma análise sensorial com 97 provadores em que foram avaliados 4 tipos de covilhetes. Entre eles, covilhete tradicional, covilhete com uma redução de 20% do seu teor em gordura e um covilhete em que foi utilizada uma margarina diferente, que na sua constituição inclui gordura de palma RSPO-MB e um outro que contém a presença desta última margarina, mas com uma redução de 20%. De um modo geral, ao longo do processamento do covilhete verifica-se uma redução na presença de Bactérias do ácido lático (BAL), microrganismos mesófilos e E. coli ao longo do tempo e ausência de Staphylococcus aureus e Listeria monocytogenes em todas as fases do processamento do covilhete, revelando uma boa higienização dos utensílios e mãos. Em termos nutricionais e físico-químicos, o covilhete com margarina 100% vegetal apresenta um maior teor em água e menor teor em humidade e pH comparativamente ao covilhete tradicional, revelando um maior risco microbiano. Enquanto, o covilhete tradicional com redução de 20% de gordura é aquele que em termos de sal apresenta menores teores em relação às restantes amostras, mas que, apresenta um teor de proteína mais elevado. Na determinação do perfil de ácidos gordos no covilhete tradicional foi detetada presença de ácidos gordos esteárico e oleico enquanto, no covilhete com a mesma margarina, mas com a redução de 20% além desses apresenta também o ácido gordo palmítico. Por outro lado, em amostras cuja margarina introduzida inclui gordura de palma, predomina a existência de ácidos gordos esteárico e oleico. Relativamente à análise sensorial das quatro formulações, os provadores apresentaram preferência pelo covilhete tradicional com um menor teor em gordura, destacando-se pelo seu aspeto estaladiço, amanteigado, amarelo e um menor teor em sal relativamente ao sabor. | Pastry products are appreciated globally. It is therefore important to study their sensory and physical-chemical characteristics in order to meet consumer demands and preferences. The ingredients used in this type of delicacy can present physical and chemical hazards, as well as biological hazards, which are the main causes of food-borne illnesses, raising questions about the food safety of products. The aim of this study was to reduce the margarine content used in the savory pastry product Covilhete through various nutritional, physical-chemical, microbiological and sensory studies. To this end, 54 covilhetes (6 batches x 3 times x 3 samples) were collected in the first phase of the work. The samples were subjected to microbiological analyses. In the second phase of the work, 24 covilhetes (3 batches x 2 samples x 4 conditions) were collected after cooking and then physico-chemical, nutritional and microbiological parameters were determined in samples of covilhete with different margarines and with a 20% reduction of each of them in their formulation. In addition, the fatty acid profile was also evaluated, where the retention time of the fatty acids present and the respective fatty acids were determined. Finally, a sensory analysis was carried out with 97 tasters in which 4 types of covilhetes were evaluated. These included a traditional covilhette, a covilhette with a 20 per cent reduction in fat content, a covilhette in which a different margarine was used, including RSPO-MB palm fat, and another with the latter margarine, but with a 20 per cent reduction. In general, there was a reduction in the presence of lactic acid bacteria (LAB), mesophilic microorganisms and E. coli over time and an absence of Staphylococcus aureus and Listeria monocytogenes at all stages of the covilhete's processing, showing good hygiene of utensils and hands.In nutritional and physico-chemical terms, the covilhete with 100% vegetable margarine has a higher water content and lower moisture content and pH compared to the traditional covilhete, revealing a greater microbial risk.While the traditional covilhete with In the second phase of the work, 24 covilhetes (3 batches x 2 samples x 4 conditions) were collected after cooking and physico-chemical, nutritional and microbiological parameters were then determined on samples of covilhete with different margarines and with a 20% reduction of each of them in their formulation. In addition, the fatty acid profile was also evaluated, where the retention time of the fatty acids present and the respective fatty acids were determined.Finally, a sensory analysis was carried out with 97 tasters in which 4 types of covilhetes were evaluated.These included a traditional covilhette, a covilhette with a 20 per cent reduction in fat content, a covilhette in which a different margarine was used, including RSPO-MB palm fat, and another with the latter margarine, but with a 20 per cent reduction. In general, there was a reduction in the presence of lactic acid bacteria (LAB), mmesophilic microorganisms and E. coli over time and an absence of Staphylococcus aureus and Listeria monocytogenes at all stages of the covilhete's processing, showing good hygiene of utensils and hands. In nutritional and physico-chemical terms, the covilhete with 100% vegetable margarine has a higher water content and lower moisture content and pH compared to the traditional covilhete, revealing a greater microbial risk. The traditional covilhete with a 20 per cent fat reduction had the lowest salt content compared to the other samples, but a higher protein content. When determining the fatty acid profile of the traditional covilhete, the presence of stearic and oleic fatty acids was detected, while the covilhete with the same margarine but with a 20% reduction also had palmitic fatty acid. On the other hand, in samples whose margarine includes palm fat, stearic and oleic fatty acids predominate. Regarding the sensory analysis of the four formulations, the tasters preferred the traditional covilhete with a lower fat content, which stood out for its crunchy, buttery, yellow appearance and lower salt content in terms of flavour.
Mostrar más [+] Menos [-]Aplicação de proteína de Spirulina platensis como emulsionante na elaboração de gelados Texto completo
2026 | 2024
Paula, Paula Eduarda Madureira Castro de | Ramalheira, Elsa | Barreiro, M.F. | Drunkler, Deisy Alessandra
Mestrado de dupla diplomação com a UTFPR, Universidade Tecnológica Federal do Paraná | O presente trabalho teve como objetivo principal desenvolver gelados utilizando emulsionantes à base de Spirulina platensis e avaliar suas propriedades físicas e sensoriais. Foram utilizados dois tipos de emulsionantes: biomassa de Spirulina platensis em pó e extrato proteico de Spirulina, tendo sido utilizado um emulsionante comercial como controle. Os gelados foram preparados com diferentes formulações (25, 50, 75 e 100% dos novos emulsionantes), levando em consideração o teor de proteína presente na biomassa e no concentrado proteico de Spirulina. As curvas de congelação dos gelados foram determinadas registando-se a temperatura de congelação ao longo do tempo. As propriedades físicas dos gelados foram avaliadas através da análise da derretibilidade, do overrun (incorporação de ar) e da textura. A análise sensorial foi realizada com a participação de 50 provadores, os quais avaliaram a aparência geral, cor, textura, sabor e apreciação geral de três gelados (controlo (gelado preparado com o emulsionante comercial), 100% biomassa e 100% concentrado proteico como emulsionantes) numa escala hedónica não estruturada. Os resultados demonstraram que as curvas de congelação dos vários gelados foram semelhantes. Pelo contrário, a adição de Spirulina (biomassa e concentrado proteico) afetou a cor dos gelados, mas não influenciou significativamente a derretibilidade e o overrun. Em termos de textura, avaliada por dois tipos de ensaio, medição da força de compressão, determinada durante o teste com a célula de corte Knife Edge (HDP/BS) (Lâmina Warner Bratzler), e da espalhabilidade (spreadability), verificou-se que os gelados com biomassa de Spirulina mostraram-se mais suaves e menos resistentes ao corte em comparação com o gelado controlo. Pelo contrário, os gelados com concentrado proteico mostraram um comportamento mais variável em relação à textura. Em relação à análise sensorial, o gelado controlo foi o melhor classificado em termos de aparência geral, sabor e apreciação geral. Pelo contrário, os provadores classificaram de forma idêntica os três gelados em relação à textura. O gelado controlo foi o preferido por cerca de 43,8% dos provadores, seguido do gelado com o concentrado de Spirulina (31,3%). Em conclusão, os resultados obtidos fornecem informações importantes para o desenvolvimento futuro de gelados mais saudáveis e sustentáveis, atendendo às preferências dos consumidores. | The present work had as main objective to develop ice creams using emulsifiers based on Spirulina platensis and to evaluate their physical and sensory properties. Two emulsifiers were used: powdered Spirulina platensis biomass and Spirulina protein extract, using a commercial emulsifier as a control. The ice creams were prepared with different formulations (25, 50, 75 and 100% of the new emulsifiers), considering the protein content present in the biomass and in the Spirulina protein concentrate. The ice cream freezing curves were determined by recording the freezing temperature over time. The physical properties of the ice creams were evaluated through the analysis of meltability, overrun (incorporation of air) and texture. Sensory analysis was carried out with the participation of 50 tasters, who assessed the overall appearance, colour, texture, flavour and general appreciation of three ice creams (control (ice cream prepared with the commercial emulsifier), 100% biomass and 100% protein concentrate as emulsifiers) on an unstructured hedonic scale. The freezing curves of the various ice creams were similar. On the contrary, adding Spirulina (biomass and concentrated protein) affected the colour of the ice creams but did not significantly influence the meltability and overrun. In terms of texture, evaluated by two types of tests, measurement of the compressive strength, determined during the test with the Knife Edge (HDP/BS) cutting cell (Warner Bratzler blade), and the spreadability, it was found that the ice creams with Spirulina biomass were softer and less resistant to cutting compared to the control ice cream. On the contrary, ice creams with protein concentrate showed a more variable behaviour concerning texture. Concerning sensory analysis, the control ice cream was ranked the highest in overall appearance, flavour and general appreciation. On the contrary, the tasters identically classified the three ice creams in relation to texture. The control ice cream was preferred by about 43.8% of the tasters, followed by the ice cream with Spirulina concentrate (31.3%). In conclusion, the present results provide important information for the future development of healthier and more sustainable ice creams to meet consumer preferences.
Mostrar más [+] Menos [-]Evaluación del comportamiento en la micropropagación de las especies Cattleya rex y Cattleya violacea mediante el sistema de inmersión temporal Texto completo
2023 | 2026
Ruiz Rios, Astriht | Coronado Jorge, Manuel Fernando
Evaluación del comportamiento en la micropropagación de las especies Cattleya rex y Cattleya violacea mediante el sistema de inmersión temporal En este estudio se determinó el medio de cultivo óptimo para la micropropagación de Cattleya rex y Cattleya violacea mediante sistema de inmersión temporal. Se evaluó el efecto de tres tiempos y tres frecuencias de inmersión sobre la proliferación de brotes, la influencia de la densidad de plántulas por sistema de inmersión temporal para la propagación de plántulas de ambas especies, la influencia del sustrato sobre el contenido de clorofila en hojas de Cattleya rex y la influencia del nitrógeno, fosforo y potasio sobre los tratamientos. El experimento se desarrolló en el laboratorio de cultivo de tejidos vegetales de la Corporación G y G Empresa Individual de Responsabilidad Limitada. Se utilizaron 4 tratamientos: T0 (3 ml./l de complejo B, 7.1 ml/l de bayfolan, 20 g./l de azúcar blanca, 40 g/l de plátano, 100 ml/l de agua de coco), T1 (T0 + 1 mg/l de ANA), T2 (T0 + 1 mg/l de 6-BAP) y T3 (T0 + 1 mg/l de ANA + 1 mg/l de 6-BAP), con un tiempo y frecuencia de inmersión de 5 minutos y 3 horas respectivamente. Se evaluó el efecto de tres tiempos de inmersión (5, 10 y 15 minutos), tres frecuencias de inmersión (3, 6 y 8 horas) y tres densidades (20, 40 y 60 plántulas). El mejor medio de cultivo determinado en ambas especies en el sistema de inmersión temporal fue a una frecuencia de 3 horas, tiempo de inmersión de 5 minutos y densidad de 20 plántulas en 500 ml. de medio de cultivo (3 ml./l de complejo B, 7,1 ml/l de bayfolan, 20 g./l de azúcar blanca, 40 g/l de plátano, 100 ml/l de agua de coco + 1 mg/l de 6-BAP). El sustrato que mejor influenció en el contenido de clorofila en hojas de Cattleya rex fue el tratamiento T2 (helecho + spagnum). El nitrógeno, fósforo y potasio fueron elementos adicionales con fines de enriquecimiento para la propagación de los explantes, siendo el bencilaminopurina el que influencio en la formación de los brotes. | Evaluation of the micropropagation performance of Cattleya rex and Cattleya violacea species using the temporary immersion system In this study, the optimal culture medium for the micropropagation of Cattleya rex and Cattleya violacea using a temporary immersion system was determined. The effect of three immersion times and three immersion frequencies on shoot proliferation, the influence of seedling density per temporary immersion system for seedling propagation of both species, the influence of substrate on chlorophyll content in leaves of Cattleya rex and the influence of nitrogen, phosphorus and potassium on the treatments were evaluated. The experiment was carried out in the plant tissue culture laboratory of Corporación G y G Limited Liability Company. Four treatments were used: T0 (3 ml./l of complex B, 7.1 ml/l of bayfolan, 20 g./l of white sugar, 40 g/l of plantain, 100 ml/l of coconut water), T1 (T0 + 1 mg/l of ANA), T2 (T0 + 1 mg/l of 6-BAP) and T3 (T0 + 1 mg/l of ANA + 1 mg/l of 6-BAP), with an immersion time and frequency of 5 minutes and 3 hours, respectively. The effect of three immersion times (5, 10 and 15 minutes), three immersion frequencies (3, 6 and 8 hours) and three densities (20, 40 and 60 seedlings) was evaluated. The best culture medium determined in both species in the temporary immersion system was at a frequency of 3 hours, immersion time of 5 minutes and density of 20 seedlings in 500 ml. of culture medium (3 ml./l of complex B, 7.1 ml/l of bayfolan, 20 g./l of white sugar, 40 g/l of plantain, 100 ml/l of coconut water + 1 mg/l of 6-BAP). The substrate that best influenced the chlorophyll content in Cattleya rex leaves was the T2 treatment (fern + spagnum). Nitrogen, phosphorus and potassium were additional elements for enrichment purposes for explant propagation, with benzylaminopurine influencing shoot formation.
Mostrar más [+] Menos [-]Resistencia antibiótica de bacterias causantes de mastitis clínica bovina en el distrito de Huanchaco de la provincia de Trujillo, 2023 Texto completo
2026 | 2024
Hernández Mendoza, Brenda Yojani | Hernández Mendoza, Brenda Yojani | Lozano Castro, Angélica Mery
El presente estudio tuvo como objetivo determinar la resistencia antibiótica de bacterias causantes de mastitis clínica bovina en el distrito de Huanchaco de la provincia de Trujillo, 2023; se colectaron 28 muestras de leche con mastitis clínica en frascos estériles manteniéndolos a 4°C hasta su remisión y procesamiento en el laboratorio de Microbiología Veterinaria del Programa de estudio de Medicina Veterinaria y Zootecnia de la Universidad Privada Antenor Orrego. Se realizó el aislamiento bacteriano por el método de estría, en agar Sangre y agar Mac Conkey incubándolas a 37°C por 24 horas, luego se realizaron las pruebas bioquímicas correspondientes para identificar el tipo de bacterias; resultando Staphylococcus aureus con el 43% de prevalencia (12/28), Streptococcus agalactiae con el 25% (7/28) y bacterias ambientales como Escherichia coli con el 25% (7/28) y Klebsiella spp. con el 7% (2/28). Se determinó la resistencia antibiótica de los agentes patógenos más importantes, encontrándose que las cepas de Staphylococcus aureus presentaban resistencia a la penicilina G (75%), en caso de Escherichia coli a tetraciclina y oxitetraciclina 85.7% en ambos casos. También se encontró que el 91% (10/11) de cepas de Staphylococcus aureus son multidrogorresistente y los patrones frecuentes fueron penicilina, cloxacilina, cefalotín, ceftiofur, tetraciclina y oxitetraciclina; y estreptomicina, penicilina y cloxacilina. Se concluye que la tasa de resistencia antibacteriana de la cepa Staphylococcus aureus es mayor frente a la penicilina en 75%; así mismo, no se encontró asociación estadísticamente significativa (p>0.05) entre la resistencia antibiótica y las cepas de Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli y Klebsiella spp. de mastitis clínica en el estudio. | The objective of this study was to determine the antibiotic resistance of bacteria causing clinical bovine mastitis in the district of Huanchaco in the province of Trujillo, 2023; 28 samples of milk with clinical mastitis were collected in sterile bottles and kept at 4°C until their referral and processing in the Veterinary Microbiology laboratory of the Veterinary Medicine and Zootechnics study program of the Universidad Private Antenor Orrego. Bacterial isolation was performed by the streak method, in Blood agar and Mac Conkey agar incubating them at 37°C for 24 hours, then the corresponding biochemical tests were performed to identify the type of bacteria; resulting in Staphylococcus aureus with 43% prevalence (12/28), Streptococcus agalactiae with 25% (7/28) and environmental bacteria such as Escherichia coli with 25% (7/28) and Klebsiella spp. with 7% (2/28). The antibiotic resistance of the most important pathogens was determined, and it was found that Staphylococcus aureus strains were resistant to penicillin G (75%), in the case of Escherichia coli to tetracycline and oxytetracycline 85.7% in both cases. It was also found that 91% (10/11) of Staphylococcus aureus strains are multidrug resistant and the frequent patterns were penicillin, cloxacillin, cephalothin, ceftiofur, tetracycline and oxytetracycline; and streptomycin, penicillin and cloxacillin. It is concluded that the antibacterial resistance rate of Staphylococcus aureus strain is higher against penicillin in 75%; likewise, no statistically significant association (p>0.05) was found between antibiotic resistance and the strains of Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli and Klebsiella spp. of clinical mastitis in the study. | Tesis
Mostrar más [+] Menos [-]Reducción del contenido de cadmio en granos de cacao (Theobroma cacao L.) fresco de piura por extracción en agua acidulada Texto completo
2025 | 2026
Pablo Ñaupari, Flora Patricia | Chire Fajardo, Gabriela Cristina | Ureña Peralta, Milber Oswaldo
Universidad Nacional Agraria La Molina. Facultad de Industrias Alimentarias. Departamento Académico de Ingeniería de Alimentos y Productos Agropecuarios | El grano de cacao es considerado uno de los productos bandera del Perú por su calidad y diversidad de grano, pero en los últimos años la presencia de cadmio en los granos de cacao y derivados viene generando preocupación por ser dañino a la salud. La actual investigación tuvo como objetivo general reducir el contenido de cadmio en granos de cacao (Theobroma cacao L.) de Piura, mediante extracción sólido-líquido con agua acidulada. A las muestras de granos de cacao se les hicieron el análisis proximal y la determinación de contenido de cadmio. La extracción sólido-líquido del metal pesado cadmio se realizó empleando una solución de agua acidulada con ácido cítrico a 0,15 M a temperatura ambiente en Lima (26 ± 0,30 °C) por un tiempo de 72 h. Se aplicó un diseño completo al azar para determinar mediante análisis de varianza (p<0,05) si hay diferencias significativas en el contenido de cadmio entre las medias de cuatro tratamientos, uno control (T0) y tres definidos por las relaciones sólido-líquido: 1/5 (T1), 1/15 (T2) y 1/25 g/mL (T3). Los valores determinados de contenido de cadmio fueron: 5,14 ± 0,02 (T0); 3,56 ±0,44 (T1); 4,62 ± 0,09 (T2) y 4,95 ± 0,09 ppm (T3), con lo que se obtuvo una disminución de contenido de cadmio de 30,74 por ciento, no encontrándose diferencia significativa (p<0,05) para los tratamientos T0 - T3 y T2 - T3. Por lo expuesto, se concluye que el método de extracción sólido-líquido con agua acidulada logró reducir el contenido de cadmio de los granos de cacao el cual podría usarse como una alternativa de solución en la etapa de poscosecha. | The cocoa bean is considered one of the flagship products of Peru due to its quality and diversity of grain, but in recent years the presence of cadmium in cocoa beans and derivatives has generated concern about being harmful to health. The general objective of the current research was to reduce the cadmium content in cocoa beans (Theobroma cacao L.) from Piura, through solid-liquid extraction with acidulated water. Proximate analysis and determination of cadmium content were carried out on the cocoa bean samples. The solid-liquid extraction of the heavy metal cadmium was carried out using a solution of acidulated water with citric acid at 0.15 M at room temperature in Lima (26 ± 0.30 °C) for a period of 72 h. A complete randomized design was applied to determine by analysis of variance (p<0.05) if there are significant differences in the cadmium content between the means of four treatments, one control (T0) and three defined by solid-liquid relationships: 1/5 (T1), 1/15 (T2) and 1/25 g/mL (T3). The determined values of cadmium content were: 5.14 ± 0.02 (T0), 3.56 ±0.44 (T1), 4.62 ± 0.09 (T2) and 4.95 ± 0.09 ppm (T3), which resulted in a decrease in cadmium content of 30.74 percent, with no significant difference found (p<0 .05) for treatments T0 - T3 and T2 - T3. From the above, it is concluded that the solid liquid extraction method with acidulated water managed to reduce the cadmium content of the cocoa beans, which could be used as an alternative solution in the post-harvest stage.
Mostrar más [+] Menos [-]Automatización de riego y monitoreo de variables meteorológicas en el cultivo de ají (Capsicum baccatum) en el Huerto - UNALM Texto completo
2025 | 2026
Zapata Salinas, Gianderi Lizbeth Zilpa | García Villanueva, Jerónimo | Sonco Cutire, Rodolfo Luis
Universidad Nacional Agraria La Molina. Facultad de Ciencias. Departamento Académico de Ingeniería Ambiental, Física y Meteorología | Esta investigación se llevó a cabo en el campo experimental del Programa de Hortalizas - Huerto de la Universidad Nacional Agraria La Molina, Lima, Perú, utilizando el cultivo de ají amarillo (Capsicum baccatum). Se utilizaron dos parcelas experimentales: una con riego convencional por goteo y otra con riego automatizado. El riego convencional por goteo fue establecido según el cronograma de riego del Huerto, mientras que el riego automatizado operaba con un microcontrolador Arduino mega, el cuál activaba las válvulas solenoides en función de los valores de humedad mínima del suelo establecidos. Cuando el sensor de humedad del suelo alcanzaba el valor de humedad mínima, determinado por la lámina de riego para cada etapa del cultivo, se aplicaba el riego hasta alcanzar el valor de agua disponible, momento en el cual cerraba la electroválvula de riego. Las necesidades hídricas del cultivo se ajustaron en función de la profundidad del sistema radicular y los valores de humedad mínima. Estos fueron: 29.74 mm en la capa de 0 a 10 cm durante la etapa I, 73.61 mm en la de 0 a 25 cm en la etapa II, 98.69 mm en la de 0 a 35 cm en la etapa III, y 119.7 mm en la de 0 a 45 cm en la etapa IV. En conclusión, existe evidencia estadística para afirmar que la parcela con riego automatizado, con un rendimiento promedio de 1.64 kg/m², superó en rendimiento a la parcela con riego convencional por goteo, que tuvo un promedio de 1.48 kg/m², lo que indica una mayor eficiencia en la producción. El riego automatizado utilizó un volumen total de agua de 57.86 m³, significativamente menor en comparación con los 95.048 m³ utilizados por el sistema de riego convencional, resaltando así la eficiencia del sistema automatizado en el uso hídrico. | This research was conducted at the experimental field of the Horticulture Program - Huerto at the National Agrarian University La Molina, Lima, Peru, utilizing the yellow chili pepper (Capsicum baccatum) crop. Two experimental plots were established: one with conventional drip irrigation and the other with automated irrigation. The conventional drip irrigation was implemented according to the irrigation schedule of the Huerto, while the automated irrigation system operated using an Arduino Mega microcontroller, which activated solenoid valves based on predetermined minimum soil moisture values. When the soil moisture sensor reached the established minimum value, determined by the irrigation requirement for each growth stage of the crop, water was applied until the available water value was reached, at which point the irrigation solenoid valve was closed. The water requirements of the crop were adjusted based on the depth of the root system and the minimum moisture values. These requirements were: 29.74 mm for the 0 to 10 cm layer during Stage I, 73.61 mm for the 0 to 25 cm layer in Stage II, 98.69 mm for the 0 to 35 cm layer in Stage III, and 119.7 mm for the 0 to 45 cm layer in Stage IV. In conclusion, there is statistical evidence to affirm that the plot with automated irrigation, with an average yield of 1.64 kg/m², outperformed the plot with conventional drip irrigation, which had an average yield of 1.48 kg/m², indicating greater efficiency in production. The automated irrigation system utilized a total water volume of 57.86 m³, significantly less than the 95.048 m³ used by the conventional irrigation system, thereby highlighting the efficiency of the automated system in water use.
Mostrar más [+] Menos [-]Inovação tecnológica na produção de aguardente de mel envelhecida com madeira de acácia | Innovation in the technological production of aged honey brandy with acacia wood Texto completo
2026 | 2024
Antunes, Carlos Alberto Lopes | Anjos, Ofélia Maria Serralha dos | Caldeira, Ilda Maria Justino | Pedro, Soraia Inês
Dissertação apresentada à Escola Superior Agrária do Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Inovação e Qualidade na Produção Alimentar. | O envelhecimento de aguardentes com madeira é um processo tecnológico valorizador da qualidade final de bebidas. Nesta fase a aguardente adquire novos aromas, melhora as suas características sensoriais e adquire cor característica, que é valorizada pelo consumidor. A aguardente de mel é um produto resultante da atividade apícola obtido pela fermentação e destilação do mel e com características aromáticas diferenciadoras. Este trabalho teve como objetivo avaliar a potencialidade de um novo destilado à base de aguardente de mel envelhecida com madeira de Acácia. O ensaio teve uma duração de três meses e foi realizado à escala laboratorial usando, no envelhecimento, madeiras, com queima média, de cinco espécies diferentes de Acácia. Para caracterizar este produto foi determinada a massa volúmica, título alcoométrico volúmico, extrato seco, acidez total, volátil e fixa, pH, características cromáticas, análise de voláteis por GC-FID e GC-MS, espetroscopia vibracional (NIR e FT-RAMAN) e análise sensorial com painel treinado. Os resultados das análises físico-químicas mostraram que o teor alcoólico se manteve constante durante o envelhecimento, a heterogeneidade das madeiras refletiu-se nas diferenças significativas encontradas no teor de extrato seco e nas características cromáticas. O envelhecimento proporcionou para todas as modalidades um aumento da acidez total e consequente aumento de pH. Verificou-se a presença de compostos voláteis minoritários (furfural, ácido decanoico, 2-feniletanol e vanilina) assim como um teor nulo de metanol nas aguardentes. Na análise sensorial, os resultados sugerem a possibilidade de diferenciação organolética das aguardentes, em função da espécie de madeira usada no envelhecimento sendo a amostra de aguardente de mel envelhecida com madeira de carvalho-francês e a amostra de aguardente de mel envelhecida com madeira de Acacia melanoxylon as mais apreciadas. | Abstract: The ageing of spirits with wood is a technological process that enhances the final quality of beverages. During this phase, the spirit acquires new aromas, improves its sensory characteristics, and develops a distinctive colour, which is valued by consumers. Honey spirit is a product resulting from beekeeping activity obtained through the fermentation and distillation of honey, with distinctive aromatic characteristics. This study aimed to evaluate the potential of a new distilled spirit based on honey spirit aged with Acacia wood. The experiment lasted for three months and was conducted on a laboratory scale using wood with medium toasting levels from five different species of Acacia for ageing. To characterize this product, density, alcoholic strength by volume, dry extract, total acidity, volatile and fixed acidity, pH, chromatic characteristics, volatile analysis by GC-FID and GC-MS, vibrational spectroscopy (NIR and FT-RAMAN), and sensory analysis with a trained panel were determined. The results of the physicochemical analyses showed that the alcohol content remained constant during ageing, and the heterogeneity of the woods was reflected in the significant differences found in the dry extract content and chromatic characteristics. Ageing led to an increase in total acidity and a consequent increase in pH for all samples. Minor volatile compounds (furfural, decanoic acid, 2-phenylethanol, and vanillin) were detected, as well as no methanol content in the spirits. In the sensory analysis, the results suggest the possibility of organoleptic differentiation of the spirits based on the wood species used for ageing, with the samples of honey spirit aged with French oak and honey spirit aged with Acacia melanoxylon wood being the most appreciated.
Mostrar más [+] Menos [-]Study of the relationship between the electrocardiographic parameters obtained with 12-lead ECG and cardiac remodelling in dogs with myxomatous mitral valve disease Texto completo
2026 | 2024
Delgado, Beatriz Teixeira | Lobo, Luís Lima | Pires, Maria João
Myxomatous mitral valve disease (MMVD) is the most prevalent cardiac disease in dogs, marked by progressive degeneration of the respective atrioventricular valve and subsequent mitral regurgitation, leading to left-cardiac remodelling. Electrocardiography is an auxiliary diagnostic tool for indirectly assessing cardiac dimensions, with the 6-lead system being the standard in clinical practice, although a 12-lead method exists. Therefore, this study aimed to compare the diagnostic ability of both electrocardiographic systems for detecting left atrium and left ventricle enlargement associated with MMVD. A total of 37 dogs participated in this prospective study conducted at the Hospital Veterinário do Porto, including 11 healthy controls and 26 animals with MMVD at stages B1 (n=13), B2 (n=8) and C (n=5). All dogs underwent a complete physical examination and a 12- lead electrocardiogram. Additionally, animals with MMVD were also subjected to an echocardiography and thoracic radiography. Compared to the control group, dogs with MMVD were older (p0.30). The vertebral heart score had a positive correlation with disease progression (p=0.024). Although the 6- and 12- lead systems had limited detection capacities and provided similar results in detecting left ventricle enlargement, the second method (particularly leads II and V4) exhibited greater sensitivity in diagnosing left atrial dilatation, previously determined by echocardiography and thoracic radiography In summary, this study proves the 12-lead system’s potential for early diagnosis of left atrial dilatation in dogs with MMVD, owing to the greater amount of information it provides compared to the 6-lead system. However, this advantage comes at the cost of reduced specificity so future research should focus on developing additional parameters or algorithms to improve the accuracy of heart chamber enlargement diagnosis. | A doença mixomatosa da válvula mitral é a doença cardíaca mais prevalente em cães, sendo caracterizada pela degeneração progressiva da respetiva válvula atrioventricular e subsequente regurgitação mitral, resultando em remodelação cardíaca esquerda. A eletrocardiografia é um método auxiliar de diagnóstico que permite avaliar indiretamente as dimensões cardíacas, sendo o sistema eletrocardiográfico de 6 derivações o padrão na prática clínica, embora exista um método de 12 derivações. Assim, este estudo teve como objetivo comparar a capacidade diagnóstica de ambos os sistemas eletrocardiográficos na deteção de dilatação do átrio e do ventrículo esquerdos associada à doença mixomatosa da válvula mitral. Para o efeito, participaram neste estudo prospetivo realizado no Hospital Veterinário do Porto um total de 37 cães, incluindo 11 animais saudáveis e 26 com doença mixomatosa da válvula mitral nos estádios B1 (n=13), B2 (n=8) e C (n=5). Cada cão foi submetido a um exame físico completo e a um eletrocardiograma de 12 derivações. Além disso, os animais doentes foram também submetidos a uma ecocardiografia e radiografia torácica. Em comparação com o grupo controlo, os cães com a doença eram mais velhos (p0.30). O vertebral heart score teve uma correlação positiva com a progressão da doença (p=0.024). Apesar dos sistemas de 6 e 12 derivações terem demonstrado uma capacidade de deteção limitada e apresentarem resultados semelhantes na deteção de aumento das dimensões do ventrículo esquerdo, o segundo método (particularmente as derivações II e V4) apresentou maior sensibilidade no diagnóstico de dilatação do átrio esquerdo, previamente determinada por ecocardiografia e radiografia torácica. Em síntese, este estudo evidencia o potencial do sistema de 12 derivações no diagnóstico precoce da dilatação do átrio esquerdo em cães com doença mixomatosa da válvula mitral, devido à maior quantidade de informação que fornece em comparação com o de 6 derivações. No entanto, esta vantagem afeta negativamente a especificidade desta metodologia pelo que trabalhos futuros deverão centrar-se no desenvolvimento de parâmetros ou algoritmos adicionais que melhorem a precisão do diagnóstico de dilatação das câmaras cardíacas.
Mostrar más [+] Menos [-]Efecto de un bioestimulante de algas marinas sobre los niveles de ácido indol-3-acético en plantas de pimiento (Capsicum annuum L.) expuestas a estrés por cadmio Texto completo
2026 | 2024
Siadén Peña, Kelly Zully Sofía | Chang La Rosa, Milagros del Rosario
Universidad Nacional Agraria La Molina. Facultad de Ciencias. Departamento Académico de Biología | La acumulación de metales pesados en suelos agrícolas como resultado de actividades mineras, industriales y agrícolas, ha sido durante mucho tiempo un problema ambiental importante que ha desencadenado numerosas investigaciones en búsqueda de remediar esta situación. El cadmio, resulta de principal interés debido a su facilidad de absorción y posterior migración hacia órganos comestibles que provocan la entrada de este elemento a la cadena alimenticia ocasionando daños crónicos en la salud. Frente a esta problemática, se desarrolló este estudio con el objetivo principal de evaluar el efecto del bioestimulante a base de algas marinas “PROSOIL EA1” sobre plantas de pimiento (Capsicum annuum L.) expuestas a estrés por cadmio; para ello se establecieron tres tratamientos con tres concentraciones de cadmio: Control (0 ppm),1.4 ppm y 2.0 ppm; y para cada tratamiento, dos grupos, uno con aplicación (PR) y otro sin aplicación (SPR) de PROSOIL EA1. Se evaluaron parámetros de crecimiento: peso seco y fresco de hojas y frutos, altura de la planta y número de hojas y frutos. Los niveles de cadmio y la aplicación del bioestimulante no tuvieron un efecto significativo sobre las muestras, a excepción del peso fresco de frutos donde la acción del bioestimulante fue notoria. Las plantas más pequeñas fueron las cultivadas con 2.0 ppm de cadmio. Asimismo, en los órganos vegetales se observó que la acumulación de cadmio sigue el orden de: raíces > tallos > hojas > frutos, siendo la menor absorción en las muestras con aplicación de PROSOIL EA1. A nivel foliar, el Tratamiento 2 con aplicación de bioestimulante (PR 1.4) redujo en 99% el acumulo de cadmio; tal efecto aliviador del bioestimulante fue reafirmado al verificarse el incremento de actividad antioxidante y compuestos fenólicos en las muestras foliares. Además, se evaluaron los niveles de pigmentos fotosintéticos: Clorofila a, b y carotenoides en donde la aplicación de PROSOIL EA1 no tuvo efecto significativo. Los niveles foliares de Ácido Indol-3-Acético (AIA), mostraron una relación directa entre los mayores niveles de cadmio y la promoción de síntesis de AIA como una respuesta al estrés; estos niveles de AIA disminuyeron con la aplicación de PROSOIL EA1. En consecuencia, se pudo determinar que PROSOIL EA1 representa una alternativa agrícola prometedora frente a la problemática del cadmio. | The heavy metals accumulation in agricultural soils as a result of mining, industrial and agricultural activities have long been a major environmental problem that has triggered numerous investigations in search of remedying this situation. Cadmium is of main interest due to its ease uptake and subsequent migration to edible organs that cause this element to enter the food chain, causing health chronic damage. Faced with this problem, this study was developed with the main objective of evaluating the effect of the seaweed based biostimulant “PROSOIL EA1” on pepper plants (Capsicum annuum L.) exposed to cadmium stress; for this, three treatments were established with three cadmium concentrations: Control (0 ppm), 1.4 ppm and 2.0 ppm; and for each treatment, two groups, one with (PR) and the other without (SPR) application of PROSOIL EA1. Growth parameters were evaluated: dry and fresh of leaves and fruits weight, plant height and number of leaves and fruits. The cadmium levels and the application of the biostimulant did not have a significant effect on the samples, except for the fruit fresh weight of where the action of the biostimulant was notable. The smallest plants were those grown with 2.0 ppm of cadmium. Likewise, in plant organs it was observed that the cadmium accumulation follows the order of roots > stems > leaves > fruits, with the lowest uptake in the samples with PROSOIL EA1 application. At the foliar level, Treatment 2 with biostimulant application (PR 1.4) decreased cadmium accumulation by 99%; such relieving effect of the biostimulant was reaffirmed when verifying the increase in antioxidant activity and phenolic compounds in the foliar samples. In addition, the levels of photosynthetic pigments were evaluated: Chlorophyll a, b, and carotenoids where the PROSOIL EA1 application had no significant effect. Leaf levels of Indole-3-Acetic Acid (IAA) showed a direct relationship between higher levels of cadmium and the promotion of IAA synthesis as a response to stress; these IAA levels decreased with the PROSOIAL EA1 application. Consequently, it was determined that PROSOIL EA1 represents a promising agricultural alternative to the cadmium problem.
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