Bacteriological Assessment of Smoked-Dried White Shrimp (Nematopalaemon hastatus Aurivillius, 1898) Sold in Calabar, Nigeria

Aim: Enumeration of bacterial counts is an important index of assessing the safety and quality of food products. This study aimed to investigate the occurrence of pathogenic bacteria in white shrimp samples obtained from major markets serving consumers in Calabar.

Study Design: This study was a cross sectional study conducted between April 2017 and April 2018.

Methodology: One hundred and twenty (120) samples of smoked dried Nematopalaemon hastatus (white shrimp) were analyzed for the presence of bacterial pathogens. Bacterial loads and identification of isolated organisms was determined using standard microbiological methods.

Results: The results showed that 66.7% of the analyzed shrimps had aerobic bacterial counts exceeding the upper permissible limit (<1.0x106Cfu/g) and 56.7% had unsatisfactory (˃20Cfu/g) Vibrio counts. The study revealed the presence of different bacteria genera namely Klebsiella, Salmonella, Pseudomonas, Serratia, Vibrio, Citrobacter, Proteus, Aeromonas, Streptococcus, Escherichia, Coagulase-negative Staphylococci (CoNS), Enterobacter and Bacillus. Predominant organism was Salmonella spp (26.7%), followed by Vibrio spp (21.7%) while the least isolated organisms were Bacillus spp and Coagulase-Negative Staphylococci (1.7%) each. The occurrence of high counts of pathogens in seafood may cause food poisoning; especially in individuals who consume this seafood raw, or lightly or insufficiently cooked.

Conclusion: Hence, seafood should be processed and packaged under standard hygienic conditions to reduce the risk of microbial contamination. In addition, public health awareness campaign targeted at consumers and vendors should be optimized with frequent monitoring by regulatory agencies.