Safety of Smoke-Dried Fish Sold in Imo State, Nigeria

This study evaluated the quality of smoke-dried fish available in open markets in Imo State, Nigeria, focusing on four prevalent fish species: Gymnarchus niloticus (Trunk fish), Rita sacertodum (Thailand fish), Clarias gariepinus (African catfish), and Ethmalos a fimbriata (Bonga fish). The research included a market survey of the fish handling practices and the quality assessments. The survey showed the different packaging materials used by the retailers, which included baskets (13.3%), cardboard boxes (40%), plastic drums (8.0%), and jute bags (37.8%). Most retailers (61.1%) displayed fish on tables for sale, while 22.2% used mats on the floor, and 16.66% used basins or small baskets. The analysis of bacterial and fungal counts in fish samples showed significant differences (P < 0.05) across the different sample locations and zones. Bacterial counts ranged from 1.05x10 ⁹ to 9.0x10 ⁷ cfu/g, while fungal counts varied from 1.0x10 ⁸ cfu/g to 9.0x10 ⁷ cfu/g. The established maximum microbiological limit of 5x10 ⁵ cfu/g, which differentiates between high and low-quality fish, was exceeded in all the markets studied and for all the fish species, raising serious concerns regarding microbial safety. The study identified four predominant microorganisms present across all markets and species: Bacillus spp ., Escherichia coli , Enterococcus spp ., and Staphylococcus spp ., highlighting the potential for contamination from multiple sources during both processing and retail stages.