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Abstract In recent years, the role of microbial communities in agricultural systems has received increasing attention, particularly concerning their impact on plant health and productivity. However, the influence of host plant genetic factors on the microbial composition of coffee plants remains largely unexplored. This study provides the first comprehensive investigation into how genotype affects the microbial communities present in the rhizosphere and fruits of Coffea canephora. Conducted on a commercial coffee farm in Brazil, we analyzed six genotypes of C. canephora var. Conilon. Soil and fruit samples were collected from which microbial DNA was extracted and sequenced, targeting the V3-V4 region of the 16 S rDNA and the ITS1 region for fungi. A total of 12,239,769 reads were generated from the 16 S rDNA and ITS1 regions. The PCoA revealed distinct patterns of beta diversity, with genotype 153 exhibiting significant isolation in soil bacterial communities. The dominant bacterial orders included Rhizobiales and Rhodobacterales, while the fungal community comprised diverse taxa from Saccharomycetales and Hypocreales. LEfSe analysis identified key metagenomic biomarkers, highlighting genotype Baiano 4 for its richness in fruit-associated taxa, whereas genotype 153 exhibited lower diversity in both soil and fruit samples. This work enhances our understanding of the microbiomes associated with different coffee genotypes, providing evidence of how host genetic variation influences microbial community composition. Our findings indicate that specific microbial taxa are enriched in the fruits and soil of various genotypes. Future research should focus on identifying these microorganisms and elucidating their specific functions within the rhizosphere and coffee fruits.

Coffee beverage presents unique organoleptic characteristics of aroma and taste. These sensory attributes depend on the chemical composition of the brewed coffee. Our objectives were to determine the sensory quality of the coffee beverage obtained by different brewing methods as assessed by untrained tasters and to characterize the solid residues of this extraction using the medium infrared spectrum. Four brewing methods were evaluated by 124 untrained consumers. The infusion method presented better global impression and preference of these consumers than the other brewing methods. Significant changes in the chemical composition of the coffee residues were observed. These changes influenced the acceptance of the consumers and can be due to the potential of retention or filtering of organic compounds by the brewing method. Thus, there was a sensory quality difference among the brewing methods and the infrared spectrum indicated the need to distinguish the classes of organic compounds for a better understanding of how coffee brewing interacts with the chemical composition.

Microorganisms influence the sensory quality of the coffee beverage through the compounds degradation or release of metabolites that diffuse into the fruit. However, type and duration of fermentation can contribute to the growth and diversity of microorganisms. Thus, the objective of this study was to analyze the microbial and sensory profile of Arabica coffees under different fruit-processing conditions and fermentation by Saccharomyces cerevisiae. Coffee cherries were used in the dry fermentation and washed fermentation at 28°C. Fermentation time ranged from 36 to 288 hours. A panel of sensory attributes was evaluated by 9 Q-graders. Mid-infrared spectra were obtained in the wavenumber range from 4000 to 650 cm−1. Microbial analyses were performed by denaturing gradient gel electrophoresis. Total sensory score for fermented coffee was higher than for unfermented coffee. In 108 and 216 hours of fermentation, the total score was higher in washed fermentation than in dry fermentation, which also shows the influence of post-harvest processing and the removal of husk on the quality of fermented coffee. Balance and body were the sensory attributes that most contributed to group formation in dry fermentation. Thus, induced fermentation increases the sensory classification of coffee beverages with positive effects on chemical and sensory profiles.

Among the different strategies adopted to improve the quality of Coffea canephora, fermentation is considered a promising technology to modulate the organoleptic characteristics of the beverage. Considering the possibility of providing a change in sensory profile through fermentation, this study aims to evaluate the chemical and sensory changes promoted by carbonic maceration in C. canephora whose effect is still unknown. The study was implemented in anaerobic conditions with different fermentation times (24, 48, 72, 96, and 120 h) and temperatures (18, 28, and 38 °C). The processed grains were subject to sensory analysis and medium infrared spectroscopy. Significant linear functional relationships were observed between total score and temperature for fermentation times of 24, 72, and 96 h and that the total score increased with fermentation temperature. Although a clear connection with sensory results was not observed, infrared analysis was able to point out important correlations with quality through stretches observed in infrared spectrum regions. Thus, there is feasibility of applying the carbonic maceration technique for grain processing of C. canephora.

The sensory profile from the Coffea canephora stands out for being denser, less sweet, presenting less acidity, and having characteristics of a marked aroma of roasted cereals. Coffee is essentially a terroir product, that is, directly influenced by environmental aspects, both natural and anthropic, in this sense, it has been argued that Coffea canephora is linked to the context of inferior coffees in sensory terms by the terroir conditions. This study aimed to characterize and investigate the terroir in different areas of Conilon coffee production, with the application of different fermentation methods, and to observe their possible gains and losses in the sensory quality of Coffea canephora. Cherry coffee samples were collected in six municipalities in the state of Espírito Santo, Brazil, which has an altitude variation from 376 m to 866 m. The study showed that the local characteristics of altitude and temperature directly influence the sensory quality, as well as demonstrated that natural fermentation in a specific altitude zone delivered good results, fixing the terroir factor. Finally, it was demonstrated that induced fermentation helps to improve sensory quality for higher altitude areas, indicating the possibility of reformulating the terroir of Conilon coffee production.