Microbiological and biochemical study of coffee fermentation

The coffee fermentation microflora were rich and mainly constituted of aero bic Gram-negative bacilli, with Erwinia and Klebsiella genuses at the highe st frequencies. The best population increase was observed with lactic acid bacteria and yeasts, whereas those microorganisms that counted on a pectin medium remained constant during the fermentation step. Qualitatively, lacti c acid bacteria belonged mainly to Leuconostoc mesenteroides species but th e others microflora were relatively heterogeneous. The microorganisms isola ted on pectin medium were Enterobacteriaceae, identified as Erwinia herbico la and Klebsiella pneumoniae, not reported as strong pectolytic strains. Th roughout coffee fermentation, 60% of the simple sugars were degraded by the total microflora and not specifically by pectolytic microorganisms.