Biblioteca do Café

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1

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Resultados da Pesquisa

Agora exibindo 1 - 3 de 3
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    Profile of organic acids and bioactive compounds in the sensory quality discrimination of arabica coffee
    (Editora UFLA, 2018-04) Ribeiro, Diego Egídio; Borém, Flávio Meira; Nunes, Cleiton Antônio; Alves, Ana Paula de Carvalho; Santos, Claudia Mendes dos; Taveira, José Henrique da Silva; Dias, Laryanne Lopes de Carvalho
    This study was conducted to investigate the potential of organic acids and bioactive compounds present in rawbeans to differentiate the sensory quality of coffee from different genotypes and processing methods. During the 2010, 2011 and 2012 crop seasons, beverage quality was analyzed, as well as the profile of organic acids and bioactive compounds caffeine, trigonelline and chlorogenic acids (3,4 and 5-CQA) in raw coffee beans from genotypes Bourbon Amarelo and Acaiá. The samples were collected in commercial fields with altitudes ranging from 932 to 1391 m, in the municipality of Carmo de Minas, MG, Brazil. Two processing methods were adopted: dry process (natural) and wet process (mechanically pulped and demucilaged coffee). All harvest and post-harvest procedures were carried out according to the main technologies for the production of specialty coffees. The sensory analysis was performed using the methodology proposed by the Specialty Coffee Association of America (SCAA). Chemical analyses were performed by High performance liquid chromatography. Data were investigated using Principal Component Analysis (PCA). The variations in the contents of organic acids and bioactive compounds were due to the coffee processing method. For genotypes Bourbon Amarelo and Acaiá, the differences in the organic acid profile, associated with caffeine, trigonelline and chlorogenic acids (3,4 and 5-CQA), were essential to differentiate the quality of mechanically pulped and demucilaged coffee. No significant differences were observed in the sensory quality of natural coffee due to the analysis of organic acids and bioactive compounds
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    Quality of natural coffee dried under different temperatures and drying rates
    (Editora UFLA, 2018-04) Borém, Flávio Meira; Isquierdo, Eder Pedroza; Alves, Guilherme Euripedes; Ribeiro, Diego Egídio; Siqueira, Valdiney Cambuy; Taveira, Jose Henrique da Silva
    The final quality of coffees depends on the preservation of the cell membranes of the coffee beans, which can be damaged during the drying. Thus, the aim of this study was to assess the immediate and latent effects of the air temperature and drying rate on the sensorial quality of natural coffees, as well as its relationship with the chemical e physiological characteristics of the coffee beans. Mature fruits of arabica coffee were harvested and sundried to moisture content of approximately 35% (wb) and then moved into a mechanical drier under different conditions of drying. This process involved the combination of three dry bulb temperatures – DBT (35°C, 40°C, and 45°C) and two dew point temperatures – DPT (2.6°C and 16.2°C). Thus, the relative humidity of the air used for drying was a dependent variable of DTB and DPT, and as consequences, different drying rates were achieved for each DBT. The increase in the drying rate for the temperatures 35°C and 40°C has a negative effect on the final quality of natural coffee beans. However, for the temperature of 45°C, the effects of the drying rate on the coffee beans are overlaid by the thermal damages that are caused at this level of heating. Higher sensory scores for coffee are linked to lower values of electrical conductivity and potassium leaching of the exudate of the coffee beans, as well as lower values of fatty acids. It is emphasized that while the temperature of 35o C is recommended for the production of specialty coffees the temperature of 45o C is not.
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    Caracterização da enzima superóxido dismutase em cafés naturais, produzidos em diferentes altitudes
    (Embrapa Café, 2015) Tosta, Murilo Ferraz; Rosa, Sttela Dellyzete Veiga Franco da; Macedo, Diego Domingues; Ribeiro, Diego Egídio; Alves, Guilherme Euripedes; Luz, Marcos Paulo Santos; Guiraldeli, Carlos Henrique Cardeal; Silva, Ana Claudia Almeida da; Borém, Flávio Meira
    O cenário da cafeicultura brasileira está em constante diferenciação, a qual indica que a comercialização do café busca o segmento dos cafés especiais. O crescimento desse setor deve-se à busca do consumidor por produtos de melhor qualidade. Para isso, é importante o conhecimento dos fatores determinantes da qualidade, que são os genéticos, os ambientais e os tecnológicos envolvidos nos processos de produção. Diante disso, este trabalho foi realizado com o objetivo de avaliar os efeitos do genótipo e da altitude, na atividade da enzima superóxido dismutase (SOD). Foram coletadas amostras de café (Coffea arabica L.), ao longo de três safras agrícolas (2009/10, 2010/11 e 2011/12), em lavouras comerciais localizadas no município de Carmo de Minas - MG, Brasil. O delineamento experimental foi baseado no estudo da interação entre variáveis ambientais e genéticas. O ambiente foi estratificado em três classes de altitude (< 1.000 m, entre 1.000 a 1.200 m e >1.200 m). Foram coletados frutos de dois genótipos, Bourbon Amarelo (frutos amarelos) e Acaiá (frutos vermelhos). Os cafés foram colhidos, processados, secos, armazenados e feitas às análises bioquímicas. Todos os procedimentos foram realizados de acordo com técnicas específicas estabelecidas. Conclui-se que a enzima SOD é um marcador pouco preciso da qualidade do café natural. Por meio das imagens, observa que de maneira geral, a atividade da enzima SOD foi maior no genótipo Acaiá, para as três faixas de altitudes.