Bacteriological and physicochemical qualities of traditionally dry-salted Pebbly fish (Alestes baremoze) sold in different markets of West Nile Region, Uganda

Abstract

The present study aimed at estimating the microbiological and chemical characteristics of traditionally dry-salted fish product, Alestes baremoze. A total of 40 random dry fish samples were collected from Arua, Nebbi, Packwach and Panyimur markets. Moisture content, pH, crude protein, crude fat and sodium chloride were analysed to determine chemical quality while Escherichia coli, Fecal streptococci, Staphylococcus aureus, Salmonella, Vibrio parahaemolyticus, Bacillus cereus and Pseudomonas spp. were determined to estimate the microbial quality. The moisture content of dry-salted fish collected from different markets was in the range of 37 to 41%. Mean values of sodium chloride obtained in the fish muscle were in the range of 13 to 14% and significantly differed across fish markets. Results from microbial analysis expressed as colony-forming units per gram of sample indicated that S. aureus was the most dominant bacteria identified in dry-salted fish sold in all markets with Nebbi market having the highest counts (9.4×106), Panyimur (2.2×106), Packwach (2.3×105) and Arua (9.6×104). Salmonella was absent in fish samples collected from three markets of Arua, Packwach and Panyimur apart from Nebbi market. E. coli counts were found to be <101 and fecal streptococci counts were relatively high in fish from Panyimur market (1.1×103). There was presence of B. cereus in all the samples ranging from 8×101 in Arua market to <20 in Nebbi and Panyimur markets. The present study has revealed that most of the fish products sold in these markets had bacterial counts beyond the maximum tolerable limits recommended by Uganda National Bureau of Standards (UNBS). There is need to control storage temperature and also ensure proper cooking procedures in order to eliminate or reduce the microorganisms to acceptable levels.