Microbial diversity and chemical characteristics of Coffea canephora grown in different environments and processed by dry method

This study aimed to assess the microbial diversity inCoffea canephora grown in four different environments of Espirito Santo state, Brazil. Coffee cherries of two different altitudes (300 and 600  m) and two terrain aspects (Southeast-facing and Northwest-facing slopes) were processed by the dry method. Samples were collected during the drying/fermentation process. Microorganisms were counted, isolated, and identified by MALDI-TOF, followed by sequencing of the ribosomal region. Sugars and organic acids were quantified by HPLC and volatile compounds of the roasted coffees were evaluated by GC–MS. Bacteria population presented a significant number of isolates as well as higher counts during the drying/fermentation process with respect to the population of yeasts. The principal genera of microorganisms found wereBacillus, Pichia,Candida, andMeyerozyma.Meyerozyma guilliermondii was the most frequent yeast in all environments. On the other hand,Pichia kluyveri was found only in coffee cherries from the 600  m altitude. The highest concentration of acetic and succinic acids observed was 6.06 mg/g and 0.84 mg/g, respectively. Sucrose concentrations ranged from 0.68 to 5.30 mg/g, fructose from 1.30 to 4.60 mg/g, and glucose from 0.24 to 1.25 mg/g. Thirty-six volatile compounds, belonging to the groups of pyrazines, alcohols, aldehydes, ketones, and furans were identified in roasted coffee, with differences between altitude and terrain aspects. Information about microbial...
Source: World Journal of Microbiology and Biotechnology - Category: Microbiology Source Type: research