Protein profiles and physiological performance of coffee seeds subjected to different processing and drying methods

O objetivo deste trabalho foi avaliar os perfis proteicos e o desempenho fisiológico de sementes de café submetidas a diferentes métodos de processamento e secagem. Foram avaliados os processamentos por via seca e úmida, e as secagens natural, em terreiro, e artificial a 60ºC, ou a 60ºC até 30% de umidade e 40ºC até teor final de 11% (base úmida). Após serem processadas e secadas, as sementes foram avaliadas quanto ao desempenho fisiológico e submetidas a análises bioquímicas, por meio da eletroforese de proteínas resistentes ao calor LEA (“late embryogenesis abundant”) e das enzimas superóxido dismutase, catalase, peroxidase, esterase, polifenoloxidase, isocitrato desidrogenase, álcool desidrogenase e malato desidrogenase. O perfil proteico de sementes de café é afetado pelo método de processamento e de secagem. Os cafés processados por via úmida apresentam maior tolerância à secagem – revelada pela maior atividade de enzimas antioxidativas e pelo melhor desempenho fisiológico – do que os processados por via seca. A atividade de proteínas resistentes ao calor e de enzimas antioxidantes é variável promissora para diferenciar a qualidade dos cafés submetidos a diferentes manejos pós‑colheita.The objective of this work was to evaluate the protein profiles and physiological performance of coffee seeds subjected to different drying and processing methods. We evaluated processing by dry and wet routes, the drying methods: natural, on the patio, and artificial at 60ºC, or at 60ºC until 30% of moisture content and 40ºC until 11% (wet basis). After processing and drying, the seeds were evaluated as to their physiological performance and subjected to biochemical analyses with electrophoresis of heat‑resistant LEA (late embryogenesis abundant) proteins and of the enzymes superoxide dismutase, catalase, peroxidase, esterase, polyphenol oxidase, isocitrate dehydrogenase, alcohol dehydrogenase, and malate dehydrogenase. The protein profile of coffee seeds is affected by the processing and drying methods. The coffee processed by wet route has higher tolerance to drying – shown by the higher activity of antioxidative enzymes and better physiological performance – than that processed by dry route. The activity of heat‑resistant proteins and antioxidant enzymes is a promising variable for the differentiation of the quality of coffee subjected to different postharvest management

Effect of storage conditions on the physical properties of coffee beans with different qualities

The quality of coffee starts in the field, and goes through the harvesting and post-harvesting processes, and continues to storage and transportation. The storage of coffee beans aims to stock a product for a certain period of time. However, factors such as quality and metabolism of the grain, water content, environmental conditions of the warehouse, type of packaging, and storage time influence the maintenance of these characteristics, and may negatively affect sensory aspects of the beverage. The use of high-barrier packaging or refrigerated storage practices are alternatives that can ensure grain quality during storage. Thus, the objective of the present study was to evaluate the behavior of raw coffee beans, of different processing and quality levels, packed in impermeable packages and stored in a refrigerated environment. The specialty coffees were previously sampled and characterized as to the drink, with two lots (one of natural coffee and the other of pulped natural coffee) evaluated with a score of 82 points, and another lot of natural coffee evaluated with a score of 84 points. They were packed in two types of packaging: moisture and gas permeable, and gas, moisture, and light impermeable. The beans were stored in ambient conditions without temperature control and in refrigerated environments. The CO2 concentration inside the packaging was measured, and the physical analyses – water content, color, and apparent specific mass – were performed. According to the results there is less variation in the water content and coloration of the grains stored in high barrier packages. The storage of the beans in refrigerated condition and in high barrier packing is efficient in the retarding of the loss of quality of the coffees during the nine months of the experimen

Qualidade do café submetido a diferentes temperaturas, fluxos de ar e períodos de pré-secagem

The objective of the present work was to evaluate the effect of different temperatures, air flow and pre-drying periods on yard in the quality of parchment coffee (Coffea arabica L.). Coffee beans were submitted to two periods of pre-drying: 1 and 3 days. After these periods, the product was submitted to drying in experimental dryers with fixed layer using two air flows (20 and 30 m3min- 1m-2) and three temperatures in the mass of beans (40, 45 and 50 ºC) with three replicates. Sensorial and chemical analyses were carried out for the characterization of coffee quality. The results indicate that increasing the pre-drying period and air flow and decreasing temperature contribute to the decrease of values of the electric conductivity and potassium leaching of the coffee beans; the total sugar content reduces significantly only with the elevation of the drying temperature for the beans submitted to 1 day of predrying; for the combined drying, the parchment coffee should be kept at least three days on the yard under appropriate drying conditions and the temperature should not be more than 40 ºC in the complementary drying to guarantee the best coffee quality.Com este trabalho, objetivou-se avaliar o efeito de diferentes temperaturas, fluxos de ar e períodos de pré-secagem em terreiro na qualidade do café cereja descascado (Coffea arabica L.). O café foi submetido a dois tempos de pré-secagem, 1 e 3 dias de terreiro. Em seguida, o produto foi submetido à secagem em secadores experimentais com camada fixa, utilizando-se dois fluxos de ar (20 e 30 m3min-1m-2) e três temperaturas médias na massa de café (40, 45 e 50ºC) com três repetições no tempo. Para a caracterização da qualidade do café foram realizadas análises químicas e sensoriais. Os resultados indicam que o aumento do período de pré-secagem, a redução do fluxo de ar e da temperatura contribuem para a redução dos valores da condutividade elétrica e da lixiviação de potássio dos grãos de café; o teor de açúcares totais é reduzido significativamente com a elevação da temperatura de secagem somente para os cafés submetidos a 1 dia de pré-secagem; para a secagem combinada, o café cereja descascado deve permanecer pelo menos três dias no terreiro sob adequadas condições de secagem e utilizar a temperatura máxima de 40 ºC na secagem complementar para favorecer a obtenção de cafés de melhor qualidade

Enzimas antioxidantes preservan la calidad del café en ambiente refrigerado

Post-harvest phases may cause biochemical and physiological changes with direct effects on coffee (Coffea sp.) grains quality during its storage. The aim of this study was to determine the relevance of antioxidant isoenzyme expression on the coffee grains quality undergoing different types of processing and storage conditions. Coffea arabica L. ripe fruits was harvested, part of them was dry processed and another part was wet processing. Immediately, the coffee was dried. After drying, some of the grains were hulled and the other part was maintained unhulled. After that, the grains were stored under refrigerate controlled conditions (10 degC and 50% relative humidity) or at 25 °C without relative humidity control for a period of 12 months. Enzymatic expression of catalase, esterase, peroxidase, and alcohol dehydrogenase enzymes was evaluated in the coffee grains in these storage conditions by electrophoretic analysis. The results were compared to the sensorial and physiological profiles of the samples. It was found that expression of enzymes of the antioxidative process is associated with changes in the quality of coffee grains. Natural coffee obtained by dry processing is more sensitive to biochemical changes than wet-processed coffee. A refrigerated environment has a beneficial effect for preserving the coffee grains showed by higher expression of catalase, peroxidase, and alcohol dehydrogenase enzymes after six months of storage in these conditions. The protection of the endosperm by the presence of the pericarp in natural coffee or the endocarp in fully-washed coffee is beneficial to maintenance of quality and is related to expression of antioxidant enzymes.Keywords: alcohol dehydrogenase, catalase, Coffea arabica L., esterase, peroxidaseLas etapas de la poscosecha pueden causar alteraciones bioquímicas y fisiológicas con efectos directos en la calidad de los granos de cafeto (Coffea spp.) durante su almacenamiento. El objetivo de este trabajo fue determinar la relevancia de la expresión de isoenzimas del proceso antioxidante, en la conservación de la calidad de los granos sometidos a diferentes tipos de procesamiento y condiciones de almacenamiento. Los frutos de Coffea arabica L. fueron cosechados en estado de maduración cereza y secados, luego de ser beneficiados por vía seca y por vía húmeda. Después del secado, parte de los granos fue trillada y otra parte conservada en coco o en pergamino. Luego, los granos fueron almacenados en condiciones controladas de aire refrigerado (10 °C y humedad relativa del 50%) o a 25 °C sin control de la humedad relativa, durante un periodo de 12 meses. La expresión enzimática de las enzimas catalasa, esterasa, peroxidasa y alcohol deshidrogenasa fue evaluada en los granos de café a lo largo del almacenamiento por medio de un análisis electroforético. Estos resultados fueron comparados con el perfil sensorial y fisiológico de las muestras. Se constató que la expresión de las enzimas del proceso antioxidante, está asociada con alteraciones en la calidad de los granos de café. El café natural obtenido por beneficio mediante secado, es más sensible a las alteraciones bioquímicas del beneficiado por vía húmeda. El efecto beneficioso de la refrigeración del aire de almacenamiento en la preservación de la calidad del café, es evidenciado por la mayor expresión de las enzimas estudiadas después de seis meses. La expresión de las enzimas del proceso antioxidante, está asociada al efecto protector del pericarpio y endocarpio.Palabras clave: alcohol deshidrogenasa,catalasa, Coffea arabica L., esterasa, peroxidas

Steps of cryopreservation of coffee seeds: physiological responses and antioxidant systems

ABSTRACT: The 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

Effect of sowing and soil wetting depth on the establishment of stand ahd performance of a bean (Phaseolus vulgaris, L.) crop

Estudou-se o efeito da profundidade De semeadura e da profundidade de molhamento do solo sobre o estabelecimento do estande e desenvolvimento da cultura do feijão (Phaseolus vulgaris, L.) através de experimento realizado em Piracicaba, de dez/88 a mar/89. Adotou-se um arranjo fatorial 2x3, com dois níveis de profundidade de semeadura (3 e 7cm) e três níveis de profundidade de molhamento do solo (10, 20 e 30cm), quatro repetições, perfazendo 24 parcelas, em um delineamento inteiramente casualizado. Os parâmetros de avaliação dos efeitos dos tratamentos foram medidos em dois estádios: 1. Durante o estabelecimento do estande (velocidade de emergência, percentagem de emergência, comprimento de hipocótilo e peso de plântulas secas); 2. No inicio da floração (área foliar e peso de plantas secas). Apos a analise e interpretação dos resultados, pode-se concluir que: (i) a profundidade de semeadura afetou somente a velocidade de emergência: seu aumento, de um modo geral, diminuiu a velocidade (ii) a profundidade de molhamento do solo de 10cm mostrou-se adequada para o estabelecimento do estande, mas inadequada para o desenvolvimento subsequente da cultura e, a de 20cm foi a que forneceu o melhor desempenho da cultura; e (iii) a maior frequência de irrigação, obtida através da menor profundidade de molhamento do solo, não levou ao melhor desempenho da culturaThe effect of sowing depth soil wetting depth on plant stand and crop performance of bean (Phaseolus vulgaris, L.) was studied at Department of Agriculture and Horticulture of the Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba (SP), University of São Paulo. The experimental design was a factorial ( 2 x 3), two levels of sowing depth (3 and 7 cm) and three levels of soil wetting depth (10, 20 and 30cm) using a completely randomized design with four replications. The parameters of the treatments were evaluated on two stages: 1. during stand establishment (rate of emergency, percentage of emergency, hipocotile length and dry seedling weight; 2. flowering initiation (leal area and dry plant weight. After analyses of the data, it could be concluded that: (i) the sowing depht affected only the raty of emergence: in general, its increase cause decrease in the rate; (ii) the soil wetting depth of 10 cm was adequate for the stand establishment but not for the subsequent development of the crops and that of 20 cm the one in which the crop and that of 20 cm the one in which the crop performance was the best; and (iii) the highest irrigation frequency obtained through the less soil wetting depth did not lead to the best performance of the cro

Effect of sowing and soil wetting depth on the establishment of stand ahd performance of a bean (Phaseolus vulgaris, L.) crop

Estudou-se o efeito da profundidade De semeadura e da profundidade de molhamento do solo sobre o estabelecimento do estande e desenvolvimento da cultura do feijão (Phaseolus vulgaris, L.) através de experimento realizado em Piracicaba, de dez/88 a mar/89. Adotou-se um arranjo fatorial 2x3, com dois níveis de profundidade de semeadura (3 e 7cm) e três níveis de profundidade de molhamento do solo (10, 20 e 30cm), quatro repetições, perfazendo 24 parcelas, em um delineamento inteiramente casualizado. Os parâmetros de avaliação dos efeitos dos tratamentos foram medidos em dois estádios: 1. Durante o estabelecimento do estande (velocidade de emergência, percentagem de emergência, comprimento de hipocótilo e peso de plântulas secas); 2. No inicio da floração (área foliar e peso de plantas secas). Apos a analise e interpretação dos resultados, pode-se concluir que: (i) a profundidade de semeadura afetou somente a velocidade de emergência: seu aumento, de um modo geral, diminuiu a velocidade (ii) a profundidade de molhamento do solo de 10cm mostrou-se adequada para o estabelecimento do estande, mas inadequada para o desenvolvimento subsequente da cultura e, a de 20cm foi a que forneceu o melhor desempenho da cultura; e (iii) a maior frequência de irrigação, obtida através da menor profundidade de molhamento do solo, não levou ao melhor desempenho da culturaThe effect of sowing depth soil wetting depth on plant stand and crop performance of bean (Phaseolus vulgaris, L.) was studied at Department of Agriculture and Horticulture of the Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba (SP), University of São Paulo. The experimental design was a factorial ( 2 x 3), two levels of sowing depth (3 and 7 cm) and three levels of soil wetting depth (10, 20 and 30cm) using a completely randomized design with four replications. The parameters of the treatments were evaluated on two stages: 1. during stand establishment (rate of emergency, percentage of emergency, hipocotile length and dry seedling weight; 2. flowering initiation (leal area and dry plant weight. After analyses of the data, it could be concluded that: (i) the sowing depht affected only the raty of emergence: in general, its increase cause decrease in the rate; (ii) the soil wetting depth of 10 cm was adequate for the stand establishment but not for the subsequent development of the crops and that of 20 cm the one in which the crop and that of 20 cm the one in which the crop performance was the best; and (iii) the highest irrigation frequency obtained through the less soil wetting depth did not lead to the best performance of the cro