The Effects Of Preservation Methods On Proximate Composition, Insect Infestation And Organoleptic Properties Of Heterobranchus longifilis, Heterotis niloticus And Chrysichthys nigrodigitatus

Abstract

A study to evaluate the effects of insecticide, Actellic 25 EC and salt solutions on proximate composition, preservation of organoleptic properties and reduction of insect infestation on traditionally smoked dried fish samples was carried out using three freshwater fishes, Heterobranchus longifilis, Heterotis niloticus and Chrysichthys nigrodigitatus. The various dehydration and smoking treatments had effect on the proximate composition. The highest moisture contents were recorded in the batch I (fresh) fish pieces, while the lowest moisture content occurred amongst the Actellic dehydrated and smoked dried fish pieces. The fat content of fish pieces dehydrated and smoked dried showed that the non dehydrated and non smoked dried fish pieces (freshfish) had the highest fat content. The highest fibre content was recorded in the batch I (fresh fish) fish species and the lowest was recorded among the fish pieces dehydrated in salt solution before smoke drying. The protein content of fish pieces variously dehydrated and smoked dried revealed that the Actellic 25 EC dehydrated smoked dried fish pieces had the highest protein content while the lowest protein contents were recorded among the fresh fish pieces not dehydrated either in salt and/or Actellic 25 EC solutions. The highest carbohydrate content was recorded in the batch I (fresh fish) while the lowest occurred among Actellic 25 EC dehydrated smoked dried fish pieces. Two insects, Dermestes sp and Necrobia sp were identified to attack dehydrated and smoked dried fishes. The smoked dried fishes had comparatively higher insect attack than the salted and / or Actellic dehydrated smoked dried fishpieces. Fish pieces preserved with Actellichad the overall best organoleptic properties while acceptability of the dried fish was bestfor salted smoked dried fish pieces. The relevance of this study to humanity is discussed.

Keywords: Deltamethrin, Freshwater Fish, Fish salting, Fish Smoking, Fish Storage, Chemical Properties, Organoleptic Properties

Animal Research International Vol. 1 (2) 2004 pp. 100-105