THE MICROBIAL DYNAMICS OF 'BORDE' FERMENTATION, A TRADITIONAL ETHIOPIAN FERMENTED BEVERAGE

Abstract

The growth pattern of various microbial groups was analyzed
during preparation of 'borde', a traditional Ethiopian fermented beverage. The ingredients consisted of wheat flour and barley malt and the product was ready for consumption within 12 h of fermentation. Malt contained high counts of aerobic mesophilic bacteria (about 1()6 cfu g-I) along with considerable numbers of lactic acid bacteria (LAB), yeasts and micrococci. The aerobic mesophilic bacterial flora at the start of fermentation was dominated by micrococci, staphylococci, members of Enterobacteriaceae and Bacillus spp_ Gram positive cocci and rods dominated after 4 h. Coli forms and other members of Enterobacteriaceae were not detected after 4 h. LAB had initial counts of lOS Cfu(rnI)"1 and reached counts as high as 109 cfu(ml)" 1 at 24 h. Hetero-fermentative lactobacilli dominated the lactic flora throughout the fermentation, although streptococci were considerably high until 12 h. The yeast count was low at the initiation of fermentation and a sharp increase was noted after 12 h. The pH of fermenting 'borde' declined from 5.2 at the start of fermentation to 3.6 at 24 h.