The aim of this research was to identify the key lactic acid bacteria associated with the fermentation of dairy traditional fermented products for developing starter cultures for controlled fermentation. A total of 100 lactic acid bacteria (LAB) were isolated from dairy traditional fermented products.Samples were obtained from eight producers in the South East of Nigeria. Isolates were identified by phenotypic and genotypic techniques including rep-PCR genotyping and sequencing of the 16S rRNA, pheS and rpoA genes. Isolates were characterised for antimicrobial activity against foodborne pathogens, exopolysaccharide (EPS) production and survival at low pH and in the presence of bile salts. All isolates clustered into 11 distinct rep-PCR groups and were identified as Lactobacillus fermentum (40%), Lactobacillus delbrueckii (23%), Streptococcus thermophilus (22%), Streptococcus infantarius (10%), Lactobacillus senioris (2%), Leuconostoc pseudomesenteriodes (2%) and Enterococcus thailandicus (1%). Lactobacillus fermentum showed a broad spectrum antimicrobial activity and survival at low pH, while Lactobacillus delbrueckii was able to tolerate low pH and produce EPS. All isolates survived in vitro exposure to 1% (w/v) bile salts over a 3-h period. L. fermentum, L. delbrueckii and S. thermophilus could be used to simulate the fermentation of dairy traditional fermented products.

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Zoom-koom is a very popular millet based beverage which has social and economic importance in Burkina Faso. The aim of this study was to investigate physico-chemical and microbiological characteristics, especially genotypic diversity of the predominant lactic acid bacteria (LAB) associated to commercial zoom-koom collected in the twelve districts of the city of Ouagadougou. Physico-chemical and microbiological characteristics were determined using standard methods. Identification of microorganisms included phenotyping, Rep-PCR typing and sequencing of 16S rRNA. The pH of the ready to drink zoom-koom samples varied from 3.2 to 4.4 while the acidity varied from 0.69 to 4.1 g of lactic acid/100 mL. Regarding the type of grains used to produce zoomkoom, 65% of the producers used unshelled millet grains, 23% used shelled grains, and 12% used both types of grains. LAB, enterobacteria and yeasts and molds counts ranged between 4.2 x 10 5 to 7.6 x 10 8 CFU/mL, 1 x 10 1 to 7.1 x 10 5 CFU/mL and 1.7 x 10 3 to 2.1 x 10 6 CFU/mL, respectively. Results showed that most of the commercial zoom-koom collected in front of schools and health centers of the twelve districts do not respect microbiological criteria of quality for enterobacteria and yeasts and molds. At the species level, Lactobacillus plantarum subsp. plantarum dominated (41.66%) zoom-koom vended nearby schools and health centers, followed by Pediococcus pentosaceus (37.5%) and Lactobacillus fermentum (20.83%).