Evaluation of chemical qualities of smoked freshwater fishes vended in major market, New Bussa, Nigeria.

Abstract

This study evaluated the biosafety of smoked freshwater fish sold in major market of New Bussa, Niger State, Nigeria. Three smoked fish samples: Labeo senegalensis (African carps), Citharinus citharus (Moonfish) and Alestes baromoze (Silverside fish) were procured from Monday market, New Bussa. Fish samples were collected weekly for ten weeks, filleted and processed for further analyses. Proximate analysis of filleted samples was carried out following standard procedure. Fish fillets were further processed and analyzed for eight (8) heavy metal: iron (Fe), copper (Cu), cadmium (Cd), chromium (Cr), nickel (Ni), zinc (Zn), lead (Pb) and cobalt (Co) concentrations using the atomic absorption spectrophotometer. The results showed that there were significant variations in nutrient compositions across the fish samples: A. baromoze had the highest protein content of 55.17±0.90%, crude fibre of 0.03±0.01%, crude fat of 8.90±0.18% as well as 4.10±0.10% of ash which was not significantly (p>0.05) different from 3.95±0.37 recorded in L. senegalensis. The results also showed that there were significant (p<0.05) variations in metal concentrations in the muscle tissue. Fe was the most accumulated of all metals. The level recorded in L. senegalensis (308.11±31.19 mg/kg) was significantly (p<0.05) higher than the least value of 61.99±10.31 mg/kg obtained in C. citharus. This high Fe level recorded in L. senegalensis exceeded the maximum permissible limits of 100 mg/kg recommended by FEPA/WHO. Pb concentration ranged from 0.74±0.29 mg/kg in L. senegalensis to 0.18±0.07 mg/kg in A. baromoze. Chromium was not detected in C. citharus and A. baromoze all through the sampling period. Based on the observations in this study, L. senegalensis accumulated Fe above permissible limit. Hence, it is advisable that biological safety is regularly monitored in fish sold in the study area so that human health will not be at risk.