Seasonal and Temperature Dependent Variations in Amino Acid Profiles of Smoke-dried Catfish (Clarias gariepinus, Burchell, 1822) using Traditional and Eco-Friendly Kilns in Lagos, Nigeria

Up to 35% of freshly harvested fish in Nigeria goes to waste because once fish dies, irreversible spoilage sets in within a few hours due to enzymatic and microbial processes which lead to a degradation in the sensory and biochemical characteristics of the harvested fish [4, 16]. Since fresh fish cannot always be consumed within a few hours, there is the need to delay the inevitable spoilage all year round. Analysis of variance (ANOVA) set at 0.05 level of significance, Duncan multiple-range test (DMRT) and T-test were carried out using Excel, PAST 3 and SPSS 20.0 software. 3.RESULTS AND DISCUSSION 3.1Traditional and Eco-Friendly Kilns Smoke-drying Process Smoke-dried catfish is an important source of income and animal protein for many Nigerians especially around water bodies in Lagos State [4] . The effective lagging/refractory material of clay, sawdust and silicon carbide with the sealing with cement of the newly constructed Eco-Friendly Kiln (EFK) ensured that even when the flame temperature within the kiln was as high as 650 0C, most of the generated heat was contained within Eco-Friendly Kiln and the temperature of the kiln when touched on the outside did not exceed 65 0C thus making it safe to use around little children, agreeing with the work of [6] who also obtained similar safe results on the kiln temperature with his lagged kiln. 3.2 Essential Amino Acids Amino acids form the building blocks of proteins and carry out different purposes in the human body [27]. The amino acid profiles of the catfish samples smoke dried using both kilns showed significant difference when the smoke-drying was done in wet and dry seasons and stored at both ambient and controlled temperatures except for Glycine, Serine and Tryptophan in dry season stored at ambient temperature, Glutamate in dry season at controlled temperature and Tyrosine and Cystine in wet season at controlled temperature.