Microbiomes associated with Coffea arabica and Coffea canephora in four different floristic domains of Brazil.

Brazilian coffee production relies on the cultivation of Coffea arabica and Coffea canephora. Climate change has been responsible for the decreasing yield of the crops in the country yet the associated microbial community can mitigate these effects by improving plant growth and defense. Although some studies have tried to describe the microorganisms associated with these Coffea species, a study that compares the microbiome on a wider spatial scale is needed for a better understanding of the terroir of each coffee planting region. Therefore, our aim was to evaluate the microbial communities harbored in soils and fruits of these Coffea species in four Brazilian floristic domains (Amazon, Atlantic Forest Caatinga, and Cerrado). One hundred and eight samples (90 of soil and 90 of fruits) were used in the extraction and sequencing of the fungal and bacterial DNA. We detected more than 1000 and 500 bacterial and fungal genera, respectively. Some soil microbial taxa were more closely related to one coffee species than the other species. Bacillus bataviensis tends to occur more in arid soils from the Caatinga, while the fungus Saitozyma sp. was more related to soils cultivated with C. arabica. Thus, the species and the planting region (floristic domain) of coffee affect the microbial composition associated with this crop. This study is the first to report microbial communities associated with coffee produced in four floristic domains that include sites in eight Brazilian states. Data generated by DNA sequencing provides new insights into microbial roles and their potential for the developing more sustainable coffee management, such as the production of biofertilizers and starter culture for fermentation of coffee cherries.

Quality of arabic coffee under different processing systems, drying methods and altitudes / Qualidade do café arábico sob diferentes sistemas de processamento, métodos de secagem e altitudes

The quality of coffee is one of the most important requirements in the commercialization of the product, and the post-harvest stage is decisive in the production of excellent coffees. The region of Mutum, MG, Brazil, is predominantly coffee-growing, with high potential for the production of specialty coffees. Due to the social and economic importance of coffee production in the Matas de Minas region, research has been demanded with the aim of providing technological information that provides improvements in quality and consequent price aggregation of the coffee bag. Among the several factors that may affect coffee quality are the processing system, the drying method and the altitude. Thus, the objective of this work was to evaluate the quality of Arabica coffee at different altitudes, submitted to different processing systems and drying methods. The work was conducted at the Cabeceira do Imbiruçu, in a randomized complete block design,with treatments arranged in a scheme comprising sub-subdivided plots (2 x 2 x 2), with four replications. In the plots, the two altitudes (850 and 1050 m), in the subplotsthe two processingsystems (dry (natural) and wet (peeled cherry)) and in the sub-subplotstwo drying methods (cement and suspended yard, both covered). Sensory and electrical conductivity analyzes were performed. The fruits of coffee trees located at altitudes of 1050 m have sensory attributes superior to those of altitudes of 850 m. The best results of the coffee flavor and aroma sensory attributes were obtained in the wet processing system when compared to a dry (natural) processing system. The electrical conductivity of the coffee beans obtained in the wet processing system was lower than that obtained in the dry processing system (natural), which gives a better beverage quality. Drying methods in suspended yard and cement yard, both with plastic cover and if technically conducted, do not influence the sensory characteristics of the Arabica coffee.

A qualidade do café é um dos requisitos mais importantes na comercialização do produto, sendo a etapa de pós-colheita determinante na produção de cafés de excelência. A região de Mutum, MG, Brasil, é predominantemente cafeeira, com elevado potencial de produção de cafés especiais. Em razão da importância social e econômica da cafeicultura para a região das Matas de Minas, pesquisas têm sido demandadas com o intuito de fornecer informações tecnológicas que proporcionem melhorias na qualidade e consequente na agregação do preço da saca de café. Dentre os diversos fatores que podem afetar a qualidade do café destacam-se o sistema de processamento, o método de secagem e a altitude. Assim, objetivou-se com a realização deste trabalho, avaliar a qualidade do café arábica em diferentes altitudes, submetido a diferentes sistemas de processamento e métodos de secagem. O trabalho foi conduzido na propriedade cabeceira do Imbiruçu, em um delineamento experimental de blocos casualizados, com os tratamentos dispostos em um esquema de parcelas sub-subdivididas (2 x 2 x 2), com quatro repetições, sendo nas parcelas, as duas altitudes (850 e 1050 m), nas subparcelas, os dois sistemas de processamento (seco (natural) e úmido (cereja descascada)) e nas subparcelas, dois métodos de secagem (cimento e terreiro suspenso, ambos cobertos). Foram realizadas análises sensoriais e de condutividade elétrica. Os frutos de cafeeiros localizados em altitudes de 1050 m possuem atributos sensoriais superiores aos de altitudes de 850 m. Os melhores resultados dos atributos sensoriais sabor e aroma do café foram obtidos no sistema de processamento via úmida quando comparado como sistema de processamento via seca (natural). A condutividade elétrica dos grãos de café obtidos no sistema de processamento via úmida foi menor que a obtida no sistema de processamento via seca (natural), o que confere melhor qualidade de bebida. Os métodos de secagem em terreiro suspenso e em terreiro de cimento, ambos com cobertura plástica e se tecnicamente conduzidos, não influenciam nas características sensoriais do café arábica.

Very beyond subjectivity: The limit of accuracy of Q-Graders.

When it comes to the sensory analysis of specialty coffees, it is necessary to discuss the protocol of tests of the Specialty Coffee Association (SCA) and the formation of Q-Graders as reliable parameters in the sensory analysis. However, the training of these Q-Graders and the use of the SCA protocol has generated discussions in the scientific community and demonstrated the importance of talking about the level of professional precision as well as the use of the protocol. This study sought to understand the relation of accuracy and efficiency of the Q-Graders and protocol in the sensory analysis of coffees. Three experiments were carried out to evaluate and test the hypotheses regarding the level of precision in relation to the shift, the number of samples and the judgment abilities of Q-Graders due to the quality of the specialty coffee and nonspecialty coffee. These three experiments were performed by seven Q-Graders in an isolated environment during three consecutive days with 137 specialty coffee samples and 7 nonspecialty coffee samples as defined by the SCA. The results indicate that the Q-Graders present high precision when evaluating excellent and outstanding coffees, as defined by the SCA. In addition, the effect of the shift did not exert fatigue on the Q-Graders. However, evaluation errors were made by the Q-Graders on very good coffee (77.00-80.00 points), which are considered as nonspecialty by the SCA, thus allowing a more in-depth discussion on what would be the boundary between a specialty and nonspecialty coffee. PRACTICAL APPLICATIONS: The article deals with the sensory evaluation process of coffees, and it has great importance to teaching and research institutions in Brazil, the largest producer, largest exporter and the country with the highest concentration of coffee scholars in the world. The article focuses on a new approach and a new way of looking at the sensory evaluation process of coffees, using the methodology of the Specialty Coffee Association to analyze the accuracy and efficiency of the Q-Graders.