Abstract

Pathogens have been isolated from some fermented foods indicating their capability of growing and surviving the fermentation process, indicating that there could be a food safety risk if these pathogens survived in fermented foods. Therefore, the need to investigate the survival of some bacterial pathogens during the fermentation and storage of iru a traditional fermented condiment from African locust beans (Parkia biglobosa). Pathogens used were Pseudomonas aeruginosa, Salmonella Typhi, Staphylococcus aureus and Escherichia coli. They were inoculated into fermenting iru and during storage at salt concentrations (2.5, 5, 7.5, and 10%) and temperatures (4, 25, 37 and 42 ° C) for 5 days. Salmonella Typhi was inhibited after 48 h, E. coli after 72 h, P. aeruginosa after 24 h while S. aureus survived until the last day during iru fermentation. Most of the pathogens survived between salt concentrations of 2.5 % and 7.5 % but their growths were inhibited at 10 %. Only S. aureus survived all the salt concentrations during storage. Temperature of 42 °C inhibited the growth of S. Typhi and E. coli over a storage period of 5 days while P. aeruginosa was inhibited at 4 °C. Inhibition of growth of pathogens during fermentation might be due to the bacteriostatic and bactericidal properties of the indigenous organisms, more so, the fermentation process is an alkaline fermentation, which makes it difficult for the growth of the pathogens introduced. Storage of iru using 10 % salt concentration could be a safe way of storing the condiment and proper hygiene condition is recommended to eradicate S. aureus.

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