A Comparative Study of the Nutritional Composition, Fatty Acid Profiles and Organoleptic Evaluation of Clarias gariepinus (African Catfish) and Oreochromis nilotius (Nile Tilapia) Raised under Wild and Pond-Cultured Systems

Abstract

Clarias gariepinus and Oreochromis niloticus are two important fish species that are widely consumed in many parts of the world. This study investigated the nutritional composition, fatty acid profiles and organoleptic evaluation of these two fish species raised under wild and pond-cultured systems. Five samples each of the species were randomly collected from Ashaka Town, Delta State, Nigeria. The proximate composition was determined using standard AOAC methods. Fatty acid profiles were analyzed using gas chromatography, while organoleptic evaluation was conducted using twenty panelists. C. gariepinus exhibited significantly lower (p<0.05) moisture content (77.76±0.45 and 79.06±0.36) and higher crude fat content (1.75±0.14 and 1.32±0.33) respectively in both wild and pond-cultured species compared to O. niloticus. C. gariepinus had higher protein content than O. niloticus in both wild and pond-cultured species. The carbohydrate content of O. niloticus was significantly higher (p<0.05) than in C. gariepinus, while the ash content of C. gariepinus and O. niloticus was not significantly different (p>0.05). Both species exhibited variations in their fatty acid profiles, with significant differences (p<0.05) observed in the levels of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). All wild and pond- cultured fish species had the same pattern of fatty acid composition SFAs > PUFAs > MUFAs except wild C. gariepinus with SFAs > MUFAs > PUFAs pattern. Pond-cultured O. niloticus and C. gariepinus had higher total n-3 PUFAs and lower n-6 PUFAs values while wild O. niloticus and C. gariepinus had lower n-3 PUFAs and higher n-6 PUFAs values. This difference was statistically significant (p<0.05). The results indicated significant organoleptic differences (p<0.05) in consumer preference between wild and pond-cultured C. gariepinus, however, O. niloticus was found to be liked similarly regardless of its source (p>0.05). These findings suggest that the type of habitat, fish species and diets have significant impacts on the proximate composition, fatty acid profiles and organoleptic attributes of fishes.