Effect of Filleting and Peeled Undeveined Pre-Processing Methods on the Microbial Load of Frozen Nigerian Tongue Sole Fish (Cynoglossus Browni) and Brown Shrimps (Parapenaeopsis Atlantica) in a Fish Processing Plant


Microbial load
Brown Shrimps
Nigerian Tongue Sole Fish
Preparation methods


The study examined the impact of filleting and peeled undeveined pre-processing methods on the microbial load of Cynoglossus browni and Parapenaeopsis atlantica in a fish processing plant. These pre-processing steps converted P. atlantica and C. browni into ready-to-cook products, such as peeled undeveined shrimps and sole fish fillets. The study involved taking twenty samples of both P. atlantica and C. browni, before and after pre-processing, to the laboratory for standard microbiological analysis. The results showed that the total plate count and Staphylococcus aureus count in P. atlantica and C. browni significantly reduced after applying the peeled undeveined and filleting pre-processing methods, except for yeast and mold, which had an increase in its count. The study also found that the microbial count of Staphylococcus aureus in frozen Sole fish decreased from 108CFU/g to 44CFU/g in sole fillets. Notably, the pre-processing methods were most effective on P. atlantica, reducing the total plate count of frozen brown shrimps from 87123CFU/g to a total plate count of 1159CFU/g in peeled undeveined shrimps. However, the pre-processing method was also least effective on P. atlantica, with a 14.5% increase in yeast and mold of frozen brown shrimps from 821CFU/g to yeast and mold of 1186.5CFU/g in PUD shrimps. Additionally, the study found that for both species in the frozen and pre-processed states, the most probable number had less than 3.0 CFU/g. The study also revealed that Escherichia coli, Salmonella spp, Shigella spp, and Vibrio parahaemolyticus were not detected. Conclusively, the microbial counts were within the limit recommended by the European Commission, indicating that these products are safe for consumption.



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