Lactic acid bacteria diversity and dynamics in Colombian coffee fermentation

Abstract

Lactic acid bacteria (LAB) are recognized in coffee fermentation as key microorganisms in forming flavor and aroma precursors associated with high-quality beverages. In Colombia, although coffees with differential sensory characteristics are produced from one region to another, only some studies have been performed on the microbiology of coffee fermentation, of which no research focused on LAB species has been reported. In this study, LAB diversity and dynamics associated with coffee fermentation in the Sierra Nevada de Santa Marta (SNSM) were determined through a temporal high-throughput sequencing approach, where the 16S rRNA gene was amplified and sequenced using the Illumina MiSeq platform. Finally, LAB species were identified using the BLASTN algorithms of the NCBI GenBank. The coffee fermentation process that lasted 36 hours was dominated by the genera Leuconostoc, followed by Lactobacillus and Weissella. Of the 118 OTUs corresponding to LAB, it was possible to identify 50 bacterial species, among which 28 are reported for the first time in coffee fermentation. Among the species widely reported in coffee fermentation are Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Lactiplantibacillus plantarum (basonym: Lactobacillus plantarum), Levilactobacillus brevis (basonym: Lactobacillus brevis), and Lactococcus lactis. While the novel reports mainly correspond to species belonging to genera that were previously recognized as Lactobacillus, such as Lactiplantibacillus, Paucilactobacillus, Secundilactobacillus, Liquorilactobacillus, Lacticaseibacillus, Schleiferilactobacillus, Loigolactobacillus, Ligilactobacillus, Lentilactobacillus, Limosilactobacillus, and Latilactobacillus. These findings suggest that the indigenous LAB of the SNSM are responsible for generating metabolites that develop specific characteristics of coffee in the region, which is why coffee from the SNSM is protected by designation of origin. Isolates of the reported species should be considered for application as starter cultures.