Seasonal and Temperature Dependent Variations in Proximate Parameters and Mineral Elements of Smoke-Dried Catfish (Clarias gariepinus, Burchell, 1822) using Traditional and Eco-Friendly Kilns in Lagos, Nigeria

Abstract

Smoke-drying Clarias gariepinus (catfish) provides animal protein and a source of livelihood in Lagos, Nigeria. Changes occurring to seasonal and mineral compositions of smoke-dried catfish using local Traditional Drum Kiln (TDK) and a newly constructed Eco-Friendly Kiln (EFK) fitted with a flame, drying and electronic components was carried out in this study. The smoke-drying process was carried out in both wet and dry seasons and smoke-dried catfish samples stored at ambient and adjusted refrigerated temperatures of 28 and 4 0C. The smoke-drying procedure was  standardized at 60 - 80 0C and kiln lasted 24 ± 3 hours. Moisture content results showed a significant difference when the catfish samples were smoke-dried using TDK and EFK and stored in ambient and controlled temperatures in both wet and dry seasons while crude protein, lipid, ash and crude fibre values were significantly different when stored only in dry season. Mineral elements phosphorus, sodium, copper, magnesium and iron showed a significant difference when stored at both temperatures and seasons using both kilns. Mineral elements were found to be most stable in smoke-dried catfish samples when stored at controlled temperatures. This work proved that standardizing smoke-drying process using both kilns resulted in good quality smoke-dried catfish but showed that higher biochemical values were obtained when EFK is used.

Key words: Nigeria, Smoke-drying Kilns, Seasons, Ambient, Controlled Temperatures