Cocoa Fermentation from Agnéby-Tiassa: Biochemical Study of Microflora

Abstract

Cocoa beans fermentation is an absolute requirement for the full development of chocolate flavor precursors. Here, we investigated the dynamic of microbial flora succession taking place in Agnéby-Tiassa cocoa fermentation. The results show that the first time of fermentation, the bacterial ecology quickly underwent changes characterized by the successional growth of lactic acid bacteria, yeasts, acetic acid bacteria and Bacillus. The dominance of Lactic acid bacteria observed at the onset of process was represented by a large proportion of homofermentative strains (98.88%). Besides, all the LAB strains were able to metabolize glucose, fructose, sucrose and a proportion of 71.35% exhibit capacity to degrade citric acid. Yeasts population was characterized by a large diversity based on their carbon profile and their ability to produce pectinolytic enzymes (13.55%) essential to degrade pectin of cocoa pulp. Furthermore, acetic acid bacteria were dominated by Acetobacter genus which represent 83.22% of AAB isolated. The later stages of fermentation were dominated by the presence of Bacillus strains which possess technological potentially as pectinolytic activity, capacity to metabolize citric acid and acidification capacity. Our results show that microflora isolated in this cocoa region producer behave differently and emphasize a microbial diversity existing in cocoa fermentation of Agnéby-Tiassa area.