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Item Alterações na qualidade do café submetido a diferentes formas de processamento e secagem(Revista Engenharia na Agricultura, 2013-10-09) Malta, Marcelo Ribeiro; Rosa, Sttela Dellyzete Veiga Franco da; Lima, Priscilla Magalhães; Fassio, Larissa de Oliveira; Santos, Juliano BatistaPesquisas recentes têm indicado várias alterações nos grãos de café decorrentes do processamento e secagem. Assim, neste trabalho objetivou-se verificar a influência da secagem lenta e secagem rápida sobre alguns parâmetros bioquímicos e fisiológicos de grãos de café e sobre a qualidade da bebida. Cafés da cultivar Catuaí Vermelho IAC 144 foram colhidos e submetidos a três formas de processamento, café natural, desmucilado e despolpado, e dois métodos de secagem, lenta à sombra em telados suspensos e secagem rápida em secadores de camada fixa a 35 ºC. Após secagem, os cafés foram submetidos às seguintes avaliações: análise sensorial, condutividade elétrica, lixiviação de potássio, atividade enzimática da polifenoloxidase, acidez total titulável e análises fisiológicas. Há interação entre métodos de processamento e de secagem sobre a qualidade sensorial do café, sendo mais evidentes os efeitos da secagem. Os cafés obtidos por via úmida tem maior tolerância à secagem do que os processados por via seca. Melhor qualidade sensorial é obtida nos cafés submetidos à secagem lenta, independentemente da forma de processamento utilizada. Cafés de melhor qualidade sensorial apresentam melhor qualidade fisiológica.Item Steps of cryopreservation of coffee seeds: physiological responses and antioxidant systems(Universidade Federal de Santa Maria, 2023-08-21) Souza, Ana Cristina de; Costa, Marina Chagas; Figueiredo, Madeleine Alves de; Pereira, Cristiane Carvalho; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza Oliveira; Pereira, Diego de Souza; Rosa, Sttela Dellyzete Veiga Franco daThe cryopreservation of plant germplasm at ultralow temperatures is an alternative technique for the long-term storage of seeds of the genus Coffea sp. However, for this technique to be successful, cell integrity must be maintained at all stages of the process on the basis of scientific research. The present study investigated validated cryopreservation protocols for Coffea arabica L. seeds and evaluate the effects on the physiological and biochemical characteristics of the seeds at each stage of the process. Seeds were dried on silica gel or with saturated saline solution, precooled or not in a biofreezer, immersed in nitrogen, and reheated in a water bath. After each of these steps, the physiological and biochemical quality of the seeds was determined. Pre-cooling is a step that can be dispensed with in the cryopreservation of Coffea arabica seeds, direct immersion in liquid nitrogen being more indicated. Coffea arabica L. seeds tolerate cryopreservation after rapid drying in silica gel up to water contents of 17 or 20% (wb), with greater survival at 17%. The enzyme activities of catalase, polyphenol oxidase and peroxidase are indicators of the quality of C. arabica L. seeds subjected to cryopreservation.Item Protein profile in arabica coffee seeds in electrophoresis gel: importance of freeze-drying(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2022-05-13) Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza de Oliveira; Padilha, LilianCoffee seeds are sensitive to desiccation and are used or stored with different moisture content values, which may affect the results of quality assessment. The aim of this study was to evaluate the changes in protein profile in electrophoresis gel in coffee seeds with different moisture content values under freeze-drying and without freeze-drying. Two lots of arabica coffee seeds were used, one of newly-harvested seeds and another of stored seeds. The seeds were dried to the moisture content values of 12, 15, 20, 25, 30, 35, and 40%. The physiological quality of the seeds was assessed through the germination test, electrical conductivity, and the profiles of the enzymes SOD, CAT, PO, GOT, MDH, and EST and of heat-resistant proteins. In general, there is an effect on expression of these enzymes in accordance with the presence of free water in the seeds. Moist seeds have little to no enzyme expression. The freeze-drying process allows preservation of coffee seed quality and does not change the functionality of the enzymes studied. The isoenzyme profiles of the antioxidant process in arabica coffee seeds are affected by the initial moisture content of the seeds. The freeze-drying process of the seeds ensures greater sensitivity in detection of the expression of these isoenzymes.Item Desiccation sensitivity from different coffee seed phenological stages(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2014) Santos, Flávia Carvalho; Rosa, Sttela Dellyzete Veiga Franco da; Pinho, Édila Vilela de Rezende Von; Cirillo, Marcelo Angelo; Clemente, Aline da Consolação SampaioMaturity stage and drying method are the factors that most influence coffee seed quality. The objective of this study was to assess the physiological quality and investigate the electrophoretic patterns of catalase and endo-ß-mannanase enzymes and heat resistant proteins in coffee seeds harvested at different phenological stages and dried under different conditions. Physiological quality was assessed when the seeds had developed the green, greenish-yellow, cherry, overripe and dry stages after three treatments: no drying, conventional drying and fast drying. After each treatment, the physiological quality of the seeds was assessed using the germination test and electrophoretic patterns of heat resistant proteins and the activity of catalase and endo-ß-mannanase enzymes. Seeds harvested at the cherry phenological stage had the best physiological quality, and the drying process reduced quality at the cherry, overripe and dry stages. This reduction was greater under the faster drying process, but at the greenish-yellow stage, seeds had better physiological quality after slow drying. Regarding the results from electrophoretic analysis, endo-ß-mannanase and catalase activities increase as the ripeness stages advance; the activity of endo-ß-mannanase is directly associated with the deterioration process; the expression of heat resistant proteins increases with maturation process and is associated with seed physiological quality.Item Identification of physiological analysis parameters associated with coffee beverage quality(Editora UFLA, 2020) Freitas, Marcella Nunes de; Rosa, Sttela Dellyzete Veiga Franco da; Pereira, Cristiane Carvalho; Malta, Marcelo Ribeiro; Dias, Carlos Tadeu dos SantosThe demand for high-quality coffee among consumers has generated a great deal of interest among producers in serving this market. Parameters for physiological analyses that can be associated with aspects of sensory analyses of coffee can ensure more reliable results for coffee quality assessments. The aim of this study was to investigate the potential of physiological analyses in determining coffee quality through multivariate analysis. Several samples from coffee bean/seed lots were placed in cold storage at 10 °C, after which the sensory quality, physiological quality, and chemical characteristics of the beans were evaluated before storage and after three and six months of storage. The variables of physiological quality in the coffee beans were correlated with sensory analysis parameters. The viability of coffee embryos revealed by the tetrazolium test results were positively correlated with the final sensory analysis score. There was a correlation of root dry matter, hypocotyl dry matter, potassium leaching, and electrical conductivity with the sensory attributes that comprise the final sensory analysis score for the coffee beans. Variation in the final sensory analysis score was explained up to 97.14% by the variables radical emergence (r2 = 2.27%), strong normal seedlings, (r2 = 0.56%), seedlings with expanded cotyledonary leaves (r2 = 0.53%), tetrazolium test results (r2 = 91.54%), and potassium leaching (r2 = 2.24%). More studies are required to enable the use of physiological analyses to complement sensory analysis.Item Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures(Editora UFLA, 2020) Coelho, Stefânia Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Clemente, Aline da Consolação Sampaio; Lacerda, Laura Nardelli Castanheira; Silva, Luciano Coutinho; Fantazzini, Tatiana Botelho; Ribeiro, Fernando Augusto Sales; Castro, Elisa de MeloDuring drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies, comparing these results to those of physiological evaluation. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea arabica were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86 oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage.Item Big Coffee VL.: Seed desiccation tolerance, sieve classification, and physiological quality(Editora UFLA, 2018-10) Souza, Ana Cristina de; Rosa, Sttela Dellyzete Veiga Franco da; Vilela, Amanda Lima; Figueiredo, Madeleine Alves de; Vilela, Ana Luiza de Oliveira; Stéphano Filho, Ricardo; Carvalho, Milene Alves de FigueiredoA coffee plant producing large fruit, seeds, and leaves in relation to conventional coffee plants, possibly generated by genetic mutation, was named Big Coffee VL. Seeds of this coffee plant were classified by size and used to establish the crop, whose progenies were designated as Big Coffee VL. large, Big Coffee VL. medium, and Big Coffee VL. small. The aim in this study was to investigate desiccation tolerance, together with size classification, and evaluate the physiological quality of the seeds of this progeny. Seeds of each type of Big Coffee VL. and of the cultivar Topázio were collected. High moisture seeds and seeds dried to 11% moisture content were evaluated to assess desiccation tolerance. Dried seeds of each Big Coffee VL. progeny and of the Topázio cultivar were classified by size in sieve testing using oblong screens for separation of peaberry seeds, and circular sieves from 22 to 12 for separation of flat seeds. All seeds were subjected to physiological evaluation through the germination test and determination of seedling dry matter. A completely randomized experimental design (CRD) was used; results were subjected to analysis of variance and means compared by the Scott-Knott test. Big Coffee VL. seeds tolerate desiccation to moisture content of 11% wet basis. Seeds of the Topázio cultivar have better physiological performance than seeds of the Big Coffee VL progenies. The bigger the seeds of Big Coffee VL., the better their physiological performance, exhibiting greater seedling dry matter.Item Activity of some isoenzymatic systems in stored coffee grains(Editora UFLA, 2014-01) Saath, Reni; Broetto, Fernando; Biaggioni, Marco Antônio Martin; Borém, Flávio Meira; Rosa, Sttela Dellyzete Veiga Franco da; Taveira, José Henrique da SilvaConsidering the worldwide consumption of coffee, it is natural that throughout the history many people have dedicated the research to markers that contribute somehow on gauging its quality. This research aimed to evaluate the biochemical performance of arabica coffee during storage. Coffee in beans (natural) and in parchment (pulped) dried in concrete terrace and in dryer with heated air were packed in jute bags and stored in not controlled environmental conditions. Enzymatic activities of superoxide dismutase, catalase, peroxidase, polyphenoloxidase, esterase and lipoxygenase in coffee grains were evaluated at zero, three, six, nine and twelve months by means of electrophoresis. Independently of the drying method, the activity of isoenzymatic complexes highlighted deteriorative processes in stored grains of coffee. The treatments 60/40° C and 60° C used to reduce the water content imposed a greater stress condition, accelerated metabolism of natural coffee in the storage with decreased activity of defense mechanisms due to latent damage in these grains. Natural coffees are more sensible to high drying temperatures and its quality reduces faster than pulped coffee in the storage.Item Alterações na coloração de grãos de café em função das operações pós-colheita(Editora UFLA, 2015-10) Abreu, Giselle Figueiredo de; Pereira, Cristiane Carvalho; Malta, Marcelo Ribeiro; Clemente, Aline da Consolação Sampaio; Coelho, Luis Filipe Serafim; Rosa, Sttela Dellyzete Veiga Franco daA avaliação da cor de grãos de café torna-se importante uma vez que cafés com coloração atípica ou com diferentes níveis de branqueamento receberão menores preços no mercado. Além da desvalorização comercial, a alteração na cor é indicativos da ocorrência de processos oxidativos e alterações bioquímicas que podem modificar os precursores do sabor e aroma dos grãos, reduzindo a qualidade da bebida. Objetivou-se, neste estudo, avaliar as características de cor de grãos de café de diferentes qualidades, os quais foram processados e beneficiados por meio de diferentes métodos, e armazenados em diferentes condições. Frutos de Coffea arabica foram colhidos no estádio cereja e processados, por via úmida e por via seca. Os grãos foram secados até atingirem 11% de teor de água e submetidos a três formas de beneficiamento (manual, mecânico e sem beneficiamento) e a duas condições de armazenamento (10 oC e 50% de umidade relativa; e 25 oC sem controle de umidade relativa). Após o armazenamento por oito meses, os parâmetros de cor dos grãos e a qualidade fisiológica e sensorial foram avaliados. A intensidade das cores verde e azul e a luminância dos grãos de café são afetadas pelos métodos de processamento, beneficiamento e condições de armazenamento. Cafés despolpados apresentam coloração verde mais intensa, em comparação aos cafés naturais. O resfriamento do ar de armazenamento de grãos de café a 10oC propicia menores índices de luminância e da coordenada b, bem como melhor qualidade fisiológica.Item Operações pós-colheita e qualidade físico-química e sensorial de cafés(Editora UFLA, 2015-04) Clemente, Aline da Consolação Sampaio; Cirillo, Marcelo Angelo; Malta, Marcelo Ribeiro; Caixeta, Franciele; Pereira, Cristiane Carvalho; Rosa, Sttela Dellyzete Veiga Franco da;Os efeitos das operações pós-colheita de processamento e secagem e as condições de armazenamento são fatores relevantes a serem considerados para análise da qualidade do café. Dependendo das condições de processamento e secagem, os grãos de café podem sofrer alterações na composição físico-química, influenciando diretamente na qualidade de bebida e consequentemente na avaliação sensorial. Para análise dos resultados, usualmente são utilizadas técnicas de estatísticas univariadas, as quais poderão proporcionar interpretações incoerentes por não considerarem o efeito conjunto entre as variáveis físico-químicas e sensoriais. Assim, objetivou-se propor uma abordagem multivariada dos dados, por meio da combinação de técnicas de componentes principais e gráficos Multi-Vari Chart, que contemple os efeitos das variáveis físico-químicas e sensoriais junto às operações de pós-colheita, na avaliação da qualidade de grãos de cafés. Foram utilizados frutos de Coffea arabica L. cv. Catuaí Amarelo IAC 62 processados para a obtenção de café natural, desmucilado e despolpado. Após o processamento, os cafés foram secados à sombra, ao sol e em secadores mecânicos e foram armazenados por doze meses em câmara fria a 10oC e 50% UR, sendo avaliados a cada quatro meses. Conclui-se que a utilização da análise de componentes principais em conjunto com a técnica gráfica multivari-chart permite compreender os efeitos conjuntos do processamento, secagem e armazenamento sobre a qualidade química e sensorial do café, bem como suas correlações. Observam-se maiores reduções na pontuação final e maiores valores de condutividade elétrica, durante o armazenamento, nos cafés naturais secados em secador.