Effect of storage time on the quality of smoked Oreochromis niloticus

Abstract

Effect of storage time on the quality of smoked Oreochromis nilotius was studied. One hundred fish samples of O. niloticus (average weight 210 ± 15g) was used. Analysis carried out include: proximate, mineral composition (Ca, Na, Fe and Mg), biochemical, amino acid and sensory evaluation. Data obtained was subjected to Analysis of Variance (ANOVA) while the sensory data was subjected to nonparametric test (Kruskal Wallis test). Proximate quality, mineral, amino acid, biochemical and sensory quality of frozen O. niloticus content reduced with increase in storage period. Na and Mg were the most abundant mineral while glutamic acid and lysine were the most concentrated non-essential amino acid (NEEA) and essential amino acid (EAA) respectively. The total volatile base nitrogen (TVBN), trimethyl amine (TMA) and peroxide values (PV) obtained are within the recommended level for good quality food while NEAA and EAA are within recommended values by WHO. The amino acid scores of the fish in relation to the amino acid scoring pattern of whole hen's egg protein indicate that lysine had the highest amino acid score. No significant (χ2= 6.624, p > 0.05) variation was observed in the score allotted for the flavor of smoked O. niloticus during storage. Smoked O. niloticus being a good source of protein, minerals and amino acids, and the quality is within good quality protein recommended by world health organization (WHO), is therefore recommended for consumption.