Full Length Research Paper

The effects of smoking on the nutritional qualities and shelf-life of Clarias gariepinus (BURCHELL 1822)

C. A. Kumolu-Johnson¹, N. F. Aladetohun² and P. E. Ndimele¹*

¹Department of Fisheries, Faculty of Science, Lagos State University, Lagos, Nigeria.

²Federal College of Fisheries and Marine Technology, Wilmont Point, Victoria Island, Lagos, Nigeria.

*Corresponding author. E-mail: drpendimele@yahoo.com. Tel: +234803-820-5109.

Accepted 3 July, 2009

   Abstract

The effects of smoking on the chemical, microbiological and sensory qualities of a commercially important freshwater fish species, Clarias gariepinus stored at 4°C for 28 days were investigated. The fish samples were collected from a research pond of Lagos State University, Lagos, Nigeria and Badagry Market, Lagos, Nigeria. The chemical profiles of the fresh and smoked fish were analyzed while the microbiological and sensory assessments were carried out weekly for a period of 28 days. Highest protein content (62.14 ± 6.67%) was recorded in smoked fish obtained from the fish pond while the least (14.23 ± 4.13%) was observed in fresh fish samples also from the fish pond. Similar results were obtained for the fat and ash contents. The differences in the proximate composition of the smoked and fresh samples were significant (p < 0.05). The total coliform count (Log₁₀ Cfu/g) of smoked fish ranged between 3.777 - 6.871 which increases with duration of storage. Sensory evaluation of smoked fish samples showed that the quality of the smoked fish decreases with duration of storage. Therefore, C. gariepinus should be stored for a short period after smoking to retain its unique taste and flavour.

Key words: Clarias gariepinus, smoking, microbiology, sensory parameters, chemical qualities.