Nutritional and Bacteriological Characterization of Smoked and Dried Clarias gariepinus Fish Sold in the Town of N’Djamena (Chad)

Abstract

In Africa—and more specifically in Chad—fish consumption remains relatively low, despite the fact that fish is a rich source of proteins, vitamins, and essential fatty acids. This study aimed to assess the microbiological and nutritional quality of processed fish consumed in N’Djamena, the capital of Chad. A total of 16 samples of Clarias gariepinus (African catfish), processed through smoking and drying, were collected from the Dembé and Taradona markets in October 2024. A survey was conducted among processors and traders to document the various processing techniques used. Nutritional analyses included determination of dry matter and moisture content using the AOAC 950.01 method (1990), total ash by AOAC 923.03 (1997), total protein via the Kjeldahl method (NF EN ISO 20483:2014), and lipid content using Soxhlet extraction. Results revealed protein contents of 49.75% ± 7.35% in dried fish and 55.27% ± 5.35% in smoked fish. Microbiological analyses of smoked fish samples indicated the presence of Staphylococcus spp. (2.1 × 10 4 ± 1.5 × 10 3 CFU/g) and Escherichia coli (1.3 × 10 3 ± 3.2 × 10 2 CFU/g). These findings highlight the need for stricter hygiene controls during fish processing and greater awareness of good manufacturing practices among stakeholders in the sector.