Comparative analysis of the proximate, fatty acids and mineral composition of selected fish species

Abstract

Proximate, minerals, fatty acids and cholesterol compositions were determined in five different freshwater fish species (Oreochromis leucostictus, Clarias garipinus, Gynarchus niloticus, Hyperopisus bebe occidentallis and Synodotus clarias) obtained from Shiroro Lake, Niger State, Nigeria using standard analytical methods. The proximate compositions were found to be 39.00 – 51.18% protein, 19.43 – 48.47% fat, 2.13 – 14.74% carbohydrate, 4.91 – 19.59% ash and 4.57 – 5.63% moisture content, with significant difference at p < 0.05 among fish species, whereas the fatty acids were found to be composed of 38.93 – 42.81% saturated fatty acids (SFA), 33.63 – 45.37% monounsaturated fatty acid (MUFA) and 7.79 – 26.10% polyunsaturated fatty acids (PUFAs) with significant difference at p < 0.05 among fish species. The cholesterol content was significantly higher in Tilapia (Oreochromis leucostictus) with 8.38 ± 0.02 mg/100g and the lowest in Catfish (Clarias garipinus) with 2.74 ± 0.04mg/100g respectively. The mineral composition (Na, Ca, K, Mg, Fe and Zn) in the five species of fish ranged from 31.63 – 49.59mg Na/100g, 8.56 – 33.60mg Ca/100g, 8.68 – 20.69mg K/100g, 6.33 – 11.77mg Mg/100g, 0.07 – 2.05mg Fe/100g and 0.13 – 0.33mg Zn/100g respectively with significant difference at p < 0.05 among the fish species. In this study, Gynarchus niloticus and Synodotus clarias have registered the highest amount of poly-unsaturated and the lowest amount of saturated fatty acids and therefore they are recommended for consumption. Notwithstanding other species should also be harnessed for their outstanding mineral contents in order to improve the essential nutrients derivable from them