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- Estudo de conservação sob atmosfera controlada na qualidade da cereja cv. Satin.Publication . Espírito Santo, Christophe; Belane, Yuran; Resende, Mafalda; Caseiro, Catarina; Beato, Helena; Reis, João; Brandão, Inês; Silveira, Ana; Riscado, Ana; Baptista, Cátia; Pintado, Cristina Miguel; Veloso, Abel; Ferreira, Dora; Andrade, Luís P.; Nunes, José; Simões, Maria Paula; Morais, Diogo Cerqueira; Teixeira, Maria Cristina Canavarro; Gaspar, Pedro Dinis; Silva, Pedro Dinho daA cerejeira (Prunus avium L.) é uma espécie pertencente à subfamília das Prunóideas e a produção de cereja apresenta elevada importância económica na região da Beira Interior, que, embora não seja a região com maior área de produção é a principal região de produção de Portugal. A cereja apresenta um elevado teor de compostos bioativos como vitamina C, fibra, antocianinas, quercetina e carotenóides relacionados com a prevenção de doenças cardiovasculares, diabetes e cancro (McCune et al., 2011; Wang et al., 2016). No entanto, este fruto não climatérico deteriora-se rapidamente após a colheita apresentando alterações na cor da pele, acastanhamento do pedúnculo, desidratação, amolecimento da polpa, diminuição da acidez e apodrecimento (Dugan & Roberts, 1997; Wang et al., 2016). A refrigeração, combinada com a utilização de atmosferas controladas, visa o atraso da deterioração e o consequente prolongamento da vida útil alargando o período de oferta. Esta técnica consiste no armazenamento a baixa temperatura num ambiente com uma concentração elevada de CO2, uma concentração baixa de O2 e uma humidade relativa elevada (Andrade et al., 2019). Os valores indicados na bibliografia relativos à concentração de CO2 variam entre 5% e 20% (Gross et al., 2016) e, para a concentração de O2, encontram-se entre 1% (Gross et al., 2016) e 10% (Ben-Yehoshua et al., 2005)
- Experimental study of the consequences of controlled atmosphere conservation environment on cherry characteristicsPublication . Andrade, Luís P.; Nunes, José; Simões, Maria Paula; Morais, Diogo Cerqueira; Teixeira, Maria Cristina Canavarro; Espírito Santo, Christophe; Gaspar, Pedro Dinis; Silva, Pedro Dinho da; Resende, Mafalda; Caseiro, Catarina; Baeto, Helena; Belane, Yuran; Ferreira, DoraCherry is a highly perishable fruit widely appreciated that is only commercialized during a short period. The post-harvest control and monitoring of this fruit is central and essential for optimal consumption in its highest state of quality. The conservation process aimed to inhibit the microbial propagation is usually accomplished by low temperatures and/or variable atmosphere composition. This paper describes experimental tests conducted in different refrigeration chambers located in industrial and laboratorial facilities. The latter one includes modified atmosphere and controlled atmosphere chambers. The tests were performed with four different concentration of O2 and CO2 in the controlled atmosphere chamber. Fruit samples extracted from each chamber were analyzed at specific residence times and several organoleptic characteristics were analyzed. The results show that the modified and controlled atmosphere maintain the fruit quality in terms of size, color, appearance and firmness, thus increasing their shelf life and food safety.
- Sistemas e dispositivos de monda automatizada de frutaPublication . Lopes, Marco; Gaspar, Pedro Dinis; Santos, Fernando Charrua; Simões, MariaA qualidade dos frutos está muito dependente da carga de uma árvore. O calibre do fruto, i.e., a sua dimensão, é um parâmetro de qualidade com valorização económica. Este parâmetro encontra‑se intimamente relacionado com o correto ajustamento da carga. Caso a poda seja pouco severa para garantir maior produção e o vingamento dos frutos (transformação das flores em frutos) for elevado, obtém‑se um excesso de carga caso se verifiquem condições climáticas favoráveis. Nesta condição, resta aos produtores fazer o correto ajustamento da carga através da monda dos frutos. A monda manual é o método mais utilizado mas requer elevada disponibilidade de mão‑de‑obra, facto muitas vezes limitativo, e por ser moroso torna‑se bastante dispendioso.
- Effect of Controlled Atmospheres and Environmental Conditions on the Physicochemical and Sensory Characteristics of Sweet Cherry Cultivar SatinPublication . Andrade, Luís Pinto de; Veloso, Abel; Espirito Santo, Christophe; Gaspar, Pedro Dinis; Silva, Pedro Dinho da; Resende, Mafalda; Beato, Helena; Baptista, Cátia; Pintado, Cristina; Paulo, Luísa; Simões, Maria PaulaSweet cherry is a highly appreciated seasonal fruit with a high content of bioactive compounds; however, this highly perishable fruit has a relatively short shelf-life period. Here, we evaluated the evolution of the physicochemical and sensory qualities of sweet cherries (Prunus avium (L.) cv. Satin) under different storage conditions, namely at a Farmers’ Organization (FO) and in a Research Centre (RC) under normal and four different conditions of controlled atmosphere for 49 days. Additional parameters were monitored, such as rotten fruit incidence and stem appearance. Temperature was the factor that most influenced the fruit quality changes over the study time. In fact, fruits stored at higher mean temperatures showed higher weight loss, higher variation in CIE-Lab colour parameters, higher firmness loss, and browner and more dehydrated stems and were less appealing to the consumer. Controlled atmosphere conditions showed a smaller decrease in CIE-Lab colour parameters and lower weight loss. The incidence of rotting was very low and was always equal or lower than 2% for all conditions. Thus, RC chamber conditions were able to sustain fruit quality parameters over 28 days under normal atmosphere conditions and 49 days under controlled atmosphere conditions.
- Review on the controlled and modified environmental conditions towards the reduction of the chilling injury of peachesPublication . Rodrigues, Cristina; Gaspar, Pedro Dinis; Simões, Maria P.; Silva, Pedro Dinho da; Andrade, Luís P.The peach is a stone fruit with a very juicy yellow flesh, smooth skin and a taste that satisfies the most demanding palate. The quality of this fruit is usually determined by texture, appearance, scent, flavor, nutritional value and food safety. At the marketing level, there is a concern for valuing visual properties, resistance, manipulation and fruit preservability, allowing a longer lifetime and less food waste. Being the peach a very sensitive fruit, which deteriorates and ripens very quickly at environment temperature, it requires conservation in cold. This is the usual method for delaying the product deterioration, both in perception of the consumer as in nutritional value, allowing to extend its shelf life. However, this process causes the chilling injury. This damage is a physiological disturbance, induced by low temperatures, which affects the quality of the fruit, reduces its storage and shelf life and impairs the organoleptic characteristics of the peach. This paper provides a review of the studies assessing the chilling injury and evaluates its consequences on peachs, providing the ideal conservation parameters of air temperature and humidity, in order to improve or enhance organoleptic characteristics.
- Current status and future trends of mechanized fruit thinning devices and sensor technologyPublication . Lopes, Marco; Gaspar, Pedro Dinis; Simões, Maria P.This paper reviews the different concepts that have been investigated concerning the mechanization of fruit thinning as well as multiple working principles and solutions that have been developed for feature extraction of horticultural products, both in the field and industrial environments. The research should be committed towards selective methods, which inevitably need to incorporate some kinds of sensor technology. Computer vision often comes out as an obvious solution for unstructured detection problems, although leaves despite the chosen point of view frequently occlude fruits. Further research on non-traditional sensors that are capable of object differentiation is needed. Ultrasonic and Near Infrared (NIR) technologies have been investigated for applications related to horticultural produce and show a potential to satisfy this need while simultaneously providing spatial information as time of flight sensors. Light Detection and Ranging (LIDAR) technology also shows a huge potential but it implies much greater costs and the related equipment is usually much larger, making it less suitable for portable devices, which may serve a purpose on smaller unstructured orchards. Portable devices may serve a purpose on these types of orchards. In what concerns sensor methods, on-tree fruit detection, major challenge is to overcome the problem of fruits’ occlusion by leaves and branches. Hence, nontraditional sensors capable of providing some type of differentiation should be investigated.
- Review of sensing methods for fruits and vegetables in the workfield and industrial environmentsPublication . Lopes, Marco; Gaspar, Pedro Dinis; Santos, Fernando Charrua; Simões, MariaThis review describes the multiple working principles and technological solutions that have been developed and applied in features extraction of horticultural products, both in the field and industrial environments. This paper intends to contribute to the development and utilization of portable agricultural equipments. Currently the research on sensing technology for fruits and vegetables is focused on computer vision equipment and algorithms, being the main purpose to support the automation of various agricultural and industrial processes, although there is a lack of integration of these technologies in useful systems.
- Automatic fruit thinning: perspectives and challengesPublication . Lopes, Marco; Gaspar, Pedro Dinis; Santos, Fernando Charrua; Simões, Maria PaulaA monda manual permanece ainda como sendo a tecnica predominate na monda de frutos. As solucoes alternatives encontradas na literatura baseiam-se num de dois conceitos: veio rotativo com elementos de impacto fleciveis e dispositivo vibratorio, apresentando ambos um carater nao seletivo.Este artigo faz uma breve descricao dessas solucoes, assim como das tecnicas de sensorizacao de productos hotofruticolas investigadas e aplicadas ate a data no campo e em ambiente industrial. Com base nos problemas, possibilidades observadas e o suporte de literatura adicional, surgerem-se possiveis linhas de desenvolvimento de sistemas e configuracoes de atuacao e sensorizacao, evidenciando as vantagens e os desafios das respetivas implementacoes.
- Influência das condições de conservação na qualidade dos pêssegosPublication . Rodrigues, Cristina; Gaspar, Pedro Dinis; Simões, Maria PaulaO pêssego é um fruto de caroço que apresenta uma polpa carnuda muito suculenta, uma pele suave e um sabor que satisfaz o paladar mais exigente. Em Portugal, a principal região produtora de pêssego é a Beira Interior, devido às suas condições edafoclimáticas que são particularmente favoráveis a esta cultura. Sendo o pêssego um fruto que se deteriora e amadurece rapidamente à temperatura ambiente, existe a necessidade de conservar e armazenar o fruto em condições controladas e modificadas, prolongando a vida útil e preservando as suas características organoléticas. A conservação pelo frio é o método mais utilizado permitindo prolongar o período de oferta e comercialização. No entanto, pode provocar alterações internas no fruto, vulgarmente designadas por “dano por frio”. Este distúrbio fisiológico é induzido por baixas temperaturas e caracteriza-se por alterações da textura da polpa que altera significativamente as características organoléticas, sem ser visível exteriormente. Segundo diversos autores a temperatura ideal de conservação de pêssegos situa-se entre 0ºC e 2,2ºC e 85% a 95% de humidade. Neste artigo são apresentados resultados de uma análise experimental realizada com a cultivar ‘Royal Time’ produzida na região da Beira Interior, avaliando o efeito da conservação em câmaras de refrigeração de três produtores distintos da região, durante um período de 42 dias, sendo retirada do frio uma subamostra de 24 frutos a cada 7 dias, dos quais 50% foram analisados no dia de saída do frio e 50% após 2 dias em ambiente doméstico. Este estudo permitiu verificar que nas condições de frio dos produtores, o dano por frio de escala 1 (dano ligeiro) é visível em 25% frutos aos 21 dias de conservação. O dano por frio de escala 3 (dano moderado grave) é visível com maior destaque em 25% frutos aos 42 dias de conservação + 2 dias em ambiente doméstico.
- Peaches Detection Using a Deep Learning Technique - A Contribution to Yield Estimation, Resources Management, and Circular EconomyPublication . Assunção, Eduardo Timóteo; Gaspar, Pedro Dinis; Mesquita, Ricardo; Simões, Maria Paula; Ramos, António; Proença, H.; Inácio, Pedro R. M.Fruit detection is crucial for yield estimation and fruit picking system performance. Many state-of-the-art methods for fruit detection use convolutional neural networks (CNNs). This paper presents the results for peach detection by applying a faster R-CNN framework in images captured from an outdoor orchard. Although this method has been used in other studies to detect fruits, there is no research on peaches. Since the fruit colors, sizes, shapes, tree branches, fruit bunches, and distributions in trees are particular, the development of a fruit detection procedure is specific. The results show great potential in using this method to detect this type of fruit. A detection accuracy of 0.90 using the metric average precision (AP) was achieved for fruit detection. Precision agriculture applications, such as deep neural networks (DNNs), as proposed in this paper, can help to mitigate climate change, due to horticultural activities by accurate product prediction, leading to improved resource management (e.g., irrigation water, nutrients, herbicides, pesticides), and helping to reduce food loss and waste via improved agricultural activity scheduling.