Effects of insect infestation on nutritional quality of some smoked fish species in Jos, Nigeria

Abstract

An assessment of the effect of insect pest infestation on the nutritional quality of four smoked fish species, Heterotis niloticus, Clarias gariepinus, Oreochromis niloticus and Protopterus annectens purchased from markets in Jos metropolis, north central Nigeria was carried out. The length of time between smoking of all the fish and procurement was between 5 to 7 days. Two insect pests associated with dried fish products; Dermestes maculatus (Degeer) and Necrobia rufipes (Degeer) were identified on the procured fish specimens. The levels of crude protein, crude fat, ash and moisture contents of the four fish species were carried out using standard methods of proximate analysis. Proximate analyses were conducted immediately after procurement and after 8-week storage period of the fish samples. Results showed significant decrease (P < 0.05) in the levels of crude protein and crude fat with increasing levels of beetle infestation over an 8-weeks storage period. Clarias gariepinus was significantly more affected (P < 0.05) than the other fish species with values of crude protein reducing from 72.00 to 50.90% for initial and final proximate analysis, respectively. However, the moisture content of the fish samples increased slightly over the 8-week storage period.