Characterisation and Safety Assessment of Bacteria Associated With Smoked Fish Sold in Two Major Markets in Ibadan

Fish is a vital source of high-quality protein and essential nutrients for millions ofpeople worldwide. In Nigeria, smoked fish is widely consumed due to its availability,affordability, and extended shelf life provided by the smoking process. However,improper handling, processing, and storage can introduce or promote bacterialcontamination, posing serious food safety risks. This study was conducted tocharacterize and assess the microbial safety of bacteria associated with smoked fishsold in two major markets in Ibadan, specifically Agbowo and Bodija markets.A total of 38 bacterial isolates were obtained from smoked fish samples collectedfrom these markets. Standard microbiological techniques, including culture-basedmethods, Gram staining, biochemical characterization, and safety assessment tests,were employed to identify and evaluate the bacterial communities present. Thebacterial species isolated included Escherichia coli, Klebsiella spp., Enterobacter spp.,Staphylococcus aureus, Bacillus spp., and Proteus spp., all of which have been linkedto foodborne illnesses and potential public health hazards. The total aerobic platecount of bacteria in Scomber japanicus (Alaran) from Bodija market was highercompared to Micromesistius poutassou (Panla) from Agbowo market. OnMacConkey agar (MAC A2), Scomber japanicus (Alaran) from Bodija market had abacterial count of 4.32 × 106 cfu/g, while on Standard Plate Count agar (SPC A2), thecount was 3.2 × 106 cfu/g. In contrast, Micromesistius poutassou (Panla) fromAgbowo market had a lower bacterial count. The bacterial count on MacConkey agar(MAC P1) was 1.02 × 106 cfu/g, while on Standard Plate Count agar (SPC P1), it was2 × 106 cfu/g. These results suggest that Scomber japanicus (Alaran) from Bodijamarket may have higher bacterial contamination than Micromesistius poutassou(Panla) from Agbowo market, possibly due to differences in hygiene practices andhandling conditions between the two markets.Biochemical tests further confirmed the metabolic characteristics of the bacterialisolates, and safety assessment tests, including DNase, hemolysis, and gelatinase tests,vwere performed to determine the pathogenic potential of the bacteria. The presence ofEscherichia coli and Klebsiella spp. in the smoked fish samples indicates possiblefecal contamination, likely introduced through polluted water, unhygienic handling, orcross-contamination during processing and storage. Additionally, Staphylococcusaureus was identified in several samples, which raises concerns due to its ability toproduce enterotoxins that cause food poisoning.The results of this study highlight the urgent need for improved hygiene practices infish smoking, handling, and marketing to reduce microbial contamination. Regulatoryagencies should enforce stricter food safety guidelines, while vendors and processorsshould be educated on best practices to minimize bacterial exposure. Implementingmodern smoking techniques, proper storage methods, and regular microbialsurveillance can significantly enhance the safety of smoked fish and protect public health