MICROBIAL LOAD

This study was carried out to assess the bacterial and fungal load of selected frozen and smoked-dried fish species sold in the New Benin Market, Oredo Local Government Area, Benin City, and to isolate and characterize the associated microorganisms. A total of fourteen (14) fish samples were randomly purchased from the market in Benin, Edo State, Nigeria. The samples were collected in sterile polythene bags to prevent contamination and transported for microbial analysis. Smoked-dried fish samples were obtained from various fish sellers, while frozen fish samples were sourced from different cold rooms. Frozen fresh smoked-dried samples were used as control. All samples were handled carefully to avoid contamination with dirt or other microorganisms. Microbiological analysis was conducted using Nutrient Agar to determine bacterial load and Potato Dextrose Agar for fungal load estimation. The results revealed that smoked-dried fish samples for Scomber scombrus had a high bacterial counts (9.6x10 3 cfu/g) compared to the frozen samples (8.0x10 3 cfu/g) and the control samples recorded the lowest bacterial load (3.4x10 3 cfu/g). Similarly, the smoked- dried fish samples showed higher fungal counts (7.0x10 2 cfu/g) than the frozen ones (6.33x10 2 cfu/g). The elevated microbial levels observed in smoked fish from the market are likely due to poor handling practices, inadequate smoking techniques employed by processors and sellers, exposure to contaminated air and septic environments. For Merluccius merluccius, the frozen fish samples had a high bacterial counts (1.5x10 4 cfu/g) compared to the smoke dried fish samples (3.4x10 3 cfu/g) and the control samples recorded the lowest bacterial load (2.0x10 3 cfu/g). Similarly, the frozen fish samples showed higher fungal counts (5.67x10 2cfu/g) than the smoke dried ones (2.0x10 2 cfu/g). The level of microbes observed in the frozen fish depends heavily on the initial contamination level, the speed of freezing, temperature fluctuations during storage, and handling practices during thawing. Frozen fish contains a residual microbial population from its initial state (harvesting, handling, processing), once the fish thaws, these surviving microbes can become active again and multiply rapidly if the temperature is favorable, potentially reaching levels that cause spoilage or illness. A total of ten (10) microorganisms, five (5) bacterial species and five (5) fungal species were isolated from both frozen and smoked-dried fish samples. The bacterial isolates included Bacillus sp., Staphylococcus sp., Proteus sp., Pseudomonas sp., and Enterobacter sp., while the fungal isolates included Aspergillus sp., accharomyces sp., Penicillium sp., Mucor sp., and Rhizopus stolonifer. Most of he fungal isolates identified are known producers of mycotoxins. There were significant differences (P > 0.05) between the frozen and smoked- dried fish amples collected from the same market, varying from one fish seller to another. This variation indicates that different handling, preservation, and marketing practices are used by fish vendors. Consequently, the microbial load reflects the hygiene standards and processing methods adopted. To ensure consumer safety, it is recommended that mechanized smoking systems be employed to completely dehydrate fish and reduce contamination risks associated with esidual moisture and the need for proper hygienic conditions during processing, handling, distribution, packaging and storage of the fish