MICROBIOLOGICAL EVALUATION OF FROZEN AND SMOKED FISH (clupeaharengus) SOLD IN MINNA METROPOLIS, NIGER STATE

Abstract

The study assessed the microbiological qualities of smoked and frozen fishes sold in Minna Metropolis, Fish and fisheries products are the most important nutritious food all over the world which represents about 15-20% of all animal protein on a global basis. Fishes are a rich source of protein commonly consumed as an alternative source of protein due to the higher cost of meat and other sources of animal protein. Four (4) samples of frozen and smoked fish were purchased from different markets within Minna metropolis and analyzed. Yeast and Bacteria were counted and identified using serial dilution method on the collected samples and dilution factor of 103 cfu/ml was used for each sample. The result showed that microbial counts of frozen fish samples were comparably higher than those of smoked fish samples. For the smoked fish, the count ranged from 7 x 103 to 14 x 103 for bacterial count and 1 x 103 to 38x 103 cfu/g for fungal count, while for the frozen fish, it ranged from 15 x 103 to 100x 103 for bacterial count and 7x 103 to 60 x 103 cfu/g for fungal count. Specific bacteria isolated with their percentage of occurrence were Bacillius subtilis(16.66%), Staphylococcus aureus(11.10%), Escherichia coli(11.10%), Streptococcus spp(27.77%), Klebsiella spp(5.55%)., Staphylococcus epidermidis(16.66%) and Bacillus cereus(11.10%), The fungal isolates were Penicillium spp(7.69%), Saccharomyces cerevisiae(30.76%), Aspergillus niger(23.07%), Aspergillus flavus (7.69%) , Aspergillus fumigatus (7.69%)and Trichrophyton spp(23.07%), This means that isolated bacterial above was observed to cause food poisoning and food infection in human. It was observed that the shelf life, method of preservation and handling processed could affect the microbial load and diversity. Therefore, adoption of a good processing practice, the use of controlled temperature in processing and proper storage of both smoked and frozen fish are highly recommended.