Thesis Abstract

Abstract
The bacteriological quality of smoked catfish (Clarias gariepinus) and mackerel (Atlantic mackerel) was investigated in this study. The aim was to assess the levels of bacterial contamination in these commonly consumed smoked fish products. A total of 60 samples, comprising 30 smoked catfish and 30 smoked mackerel, were collected from different markets and retail outlets. The samples were analyzed for total viable count (TVC), total coliform count, and specific bacterial pathogens including Escherichia coli, Salmonella spp., and Staphylococcus aureus. The results revealed that the smoked catfish samples had higher levels of bacterial contamination compared to the smoked mackerel samples. The mean TVC for smoked catfish was found to be 6.78 ± 0.23 log CFU/g, while the smoked mackerel had a mean TVC of 5.41 ± 0.19 log CFU/g. Similarly, the total coliform count was significantly higher in smoked catfish (4.62 ± 0.17 log MPN/g) than in smoked mackerel (3.79 ± 0.15 log MPN/g). In terms of specific pathogens, Escherichia coli was detected in 40% of the smoked catfish samples, with a mean count of 3.89 ± 0.14 log CFU/g, while only 20% of the smoked mackerel samples tested positive for E. coli with a mean count of 2.78 ± 0.11 log CFU/g. Salmonella spp. were absent in all smoked mackerel samples but were detected in 10% of smoked catfish samples. Staphylococcus aureus was found in 30% of smoked catfish samples with a mean count of 3.45 ± 0.12 log CFU/g, whereas it was present in only 10% of smoked mackerel samples with a mean count of 2.98 ± 0.09 log CFU/g. These findings indicate that there is a higher risk of bacterial contamination in smoked catfish compared to smoked mackerel. Proper handling, processing, and storage practices should be strictly enforced to ensure the safety and quality of smoked fish products. Consumers should also be educated on the potential health risks associated with consuming contaminated fish products to prevent foodborne illnesses. Further research is recommended to investigate the sources of contamination and to develop strategies for improving the bacteriological quality of smoked fish products.

Thesis Overview

1.0 INTRODUCTIONA fish is any member of a paraphyletic group of organisms that consists of all gill-bearing aquatic craniates that lack limbs with digits (FAO, 2011). Included in this definition are the living hagfish, lampreys, and caritlagionus and bony fish, as well as various extinct related groups. Most fish are ectothermic (‘’cold-blooded’’), allowing their body temperature to vary as ambient temperature change, though some of the large active swimmers like white shark and tuna can hold a higher core temperature. (Helfman et al., 1999).Fish are an important resource for humans worldwide, especially as food. Commercial and subsistence fishers hunt fish in wild fisheries or farm them in ponds or in cages in the ocean. They are also caught by recreational fishers, kept as pets, raised by fish keepers, and exhibited in public aquaria. Fish have had a role in culture through the ages, serving as deities, religious symbols, and as the subjects of art, books, and movies (Eschmeyer and Fong 2013).Fish is an important source of animal protein in the diet of man. Smoked or dried fish is a traditional part of the diet of a large section of the world’s population. However, the gap between the demand and supply of fish is widening due to increase in population, poor post-harvest handling, unconventional fish species. For instance, the estimated fish demand in Nigeria in 1994 was put at 1,139,833 tonnes consumption of 12.0kg which was considered globally adequate for normal and health growth. However, only 280,307 tonnes were produced, indicating a deficit of 94,705,737. (FDF, 2007). 1.2 STATEMENT OF PROBLEMFish is the main source of protein for the people living around National Root Crops Research Institute, Umudike, and given the prevalence of water and food borne diseases in the environment, it is in order that all possible infection routes of the pathogens are investigated and possible mitigation measures outlined. It is with this in mind that the research proposal is develop.1.3 JUSTIFICATION OF STUDYFish also forms a major source of employment. Its transportation from the pond to the market is done using baskets, manila sacks. The pond most time lacks electricity and this makes it impossible for the fish dealers to have a cold storage facilities. In addition, roads serving these areas are very poor and inaccessible during rainy seasons. These have led to a scenario where the fish that is not sold fresh to the processing individuals, being processed in some way. Processing should be done in form of smoking, sun-drying of frying. The treatments employed in the processing are mostly inadequate resulting in the spoilage of the processed products.OBJECTIVEThe objective of this study includes;to ascertain the Bacterial quality of Scent leaves Ocimum gratissimum treatments on the smoked fish samplesidentified microbial loads in the smoked fish samples