Microbial Quality and Chemical Safety of Modern Convective Smoked Guinean Barracuda Fish from Lagos State, Nigeria

Abstract

Safety of street-vended smoked fish has become public health issue in Nigeria in recent times. This study therefore was carried out to assess the microbial quality and chemical safety of modern convective smoked Guinean barracuda fish from Lagos State, Nigeria. Fresh fish (100) samples were collected from twenty major processing centres from Lagos State, Nigeria and the samples were smoked with modern convective kiln. The fresh and smoked fish samples were analysed for proximate, quality and rancidity indices (PV, TBA, TVB-N, TMA and FFA), polycyclic aromatic hydrocarbon (PAH), heavy metals and microbiological (coliform, fungi, Listeria monocytogenes, Salmonella paratyphi and Staphylococcus aureus ). The results revealed that the mean moisture, protein, fat, crude fibre, ash and carbohydrate contents (%) of smoked fish samples ranged from 8.34-9.78, 57.43-63.71, 13.24-17.47, 1.36-1.92, 1.89-2.89 and 8.29-12.12 respectively. The vales of PV, TBA, TVB-N, TMA and FFA were in the range of 7.23-9.53 meq. peroxide/kg, 1.11-1.51, 1.00-1.51 mg Mol/kg , 15.36-17.91 mgN/kg and 2.03-2.49 mgN/kg respectively. The results of PAHs showed the presence of sixteen (16) PAHs compounds in the smoked fish samples. However, only few of the sixteen PAHs compounds detected are above the 5.0 μg /kg B (α) P maximum permissible levels stipulated by EU Regulation 1881/2006. The concentrations (μg/g) of Hg, Pb, Cd, and Cr in the smoked fish samples were in the range of 0.0016-0.0024, 0.0012-0.0023, 0.0015-0.0023, and 0.0629-0.0856 respectively. The microbiological analysis revealed the presence of L. monocytogenes and S. aureus in the smoked fish samples. In conclusion, study showed that smoked Guinean barracuda fish may constitute higher risks (chemical) to consumers if adequate precaution is not taken but the samples are microbiological safe.