YORO Thierry Dezay^1,, ATTCHELOUWA Kouadio Constant¹, OUATTARA Gnénépari Odjo Mahoua¹, KARAMOKO Detto¹, Andrée Emmanuelle SIKA², KOUASSI koffi II Nazaire³

Traditional honey beer is an artisanal fermented beverage widely consumed in several regions of Africa, and its organoleptic characteristics result from the activity of a complex microbial community. The aim of this study was to evaluate the microbial diversity and to molecularly identify the Bacillus species and yeasts associated with the fermentation of traditional honey beer produced in Nangakaha, in the Korhogo Department, Côte d'Ivoire. Fifteen samples were collected and analyzed at different stages of fermentation (0, 24, 48, and 72 h). Microbial loads were determined by plate counting on selective culture media, while the phenotypic identification of the isolates was based on their morphological and biochemical characteristics. Molecular identification was performed by amplification of the 16S rRNA gene for bacteria and the internal transcribed spacer (ITS) region for yeasts, followed by amplicon sequencing. The results showed a progressive increase in microbial populations up to 48 h of fermentation, followed by a decline at 72 h. The highest microbial loads reached 6.06 ± 0.17 log CFU/mL for Bacillus sp. and 7.25 ± 0.22 log CFU/mL for yeasts. Molecular analysis identified Bacillus cereus and Bacillus sp. among the bacterial isolates, and Candida tropicalis and Pichia kudriavzevii among the yeasts. The predominance of yeasts throughout the fermentation process highlights their major role in the biotransformation of fermentable sugars. This study contributes to the understanding of the microbial biodiversity of traditional fermented beverages in Côte d'Ivoire and provides valuable information that could be used to improve fermentation processes and to select suitable starter cultures.

Traditional honey beer, traditional fermentation, Bacillus cereus, Candida tropicalis, Pichia kudriavzevii, microbial diversity, molecular identification