Comparative Effects of Neem Wood and Charcoal Smoking on the nutrient Composition of farmed African Catfish (Clarias gariepinus)

Abstract

Smoking has been practiced for centuries as a preservation technique, combining dehydration with the antimicrobial and antioxidant properties of smoke compounds. This study evaluated the effects of neem wood (Azadirachta indica) and charcoal as smoking fuels on the proximate composition of African catfish (Clarias gariepinus). A Completely Randomized Design (CRD) comprising three treatments, fresh fish (control), neem wood-smoked fish, and charcoal-smoked fish, was employed with three replicates each. A total of 45 pieces (15kg) of healthy catfish (300–400 g) were processed and smoked for 6 hours using traditional smoking kilns. Proximate composition analyses, including moisture, crude protein, lipid, ash, and nitrogen-free extract (NFE), were conducted using standard procedures. Results showed significant differences (P < 0.05) among treatments. Fresh fish had the highest moisture (20.40%), ash (4.80%), lipid (7.51%), and NFE (35.59%) contents, while smoked samples exhibited markedly higher crude protein levels. Neem-smoked fish recorded significantly higher crude protein (53.01%) and ash (4.33%) contents than charcoal-smoked fish (51.33% and 3.70%, respectively). Charcoal-smoked fish showed the lowest moisture content (7.62%), indicating greater dehydration efficiency. Lipid contents did not differ significantly between the smoking treatments. The findings demonstrate that smoking substantially improves the protein concentration of catfish through moisture reduction, with neem wood producing nutritionally superior smoked fish compared to charcoal. Therefore, neem wood is recommended as a sustainable and effective smoking fuel for enhancing the nutritional quality of smoked Clarias gariepinus.