A. O. Isaac , S. E. Olusola , O. A. Oyelese

Department of Wildlife and Fisheries Management, University of Ibadan, Nigeria
Author    Correspondence author
International Journal of Aquaculture, 2014, Vol. 4, No. 21   doi: 10.5376/ija.2014.04.0021
Received: 28 Mar., 2014    Accepted: 21 May, 2014    Published: 24 Jun., 2014

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Isaac A.O., Olusola S.E., and Oyelese O.A., 2014, Microbial safety and quality of smoked Clarias gariepinus (Burchell, 1822) on different concentration of preservatives during ambient storage, International Journal of Aquaculture, Vol.4, No.21: 123-130 (doi: 10.5376/ija.2014.04.0021)

This experiment was conducted to assess the microbial safety and quality of smoked Clarias gariepinus using different concentrations of pepper and salt spice mixture as preservatives. Ninety catfish, Clarias gariepinus (1,000 – 1,250g) were allocated to five treatments and replicated twice. The prepared weight to weight spice mixture of pepper 50% and salt 50% was neatly rubbed on the Clarias gariepinus using different concentrations after degutting: E₁= 0%, E₂= 5%, E₃ =10%, E₄= 15%, E₅ = 20%. The Clarias gariepinus were cold smoked in an oven between 40℃ to 65℃ for 6hrs and hot smoked between 120-150℃ for 18hrs. This study were carried out for 18 weeks were proximate composition, organoleptic assessment, Total Viable Count (TVC), biochemical parameters such as Peroxide Value (PV), Thiobarbituric Acid (TBA), Free Fatty Acid (FFA) and Total Volatile Base (TVB) were investigated. Data were analyzed using descriptive statistics and ANOVA at p = 0.05. Results showed that crude protein of Clarias gariepinus were better in treated groups compared to the control and increased with increasing level of pepper and salt spices at 18weeks. Also, better organoleptic assessment was recorded in treated groups compared to the control, best assessment was recorded in 20% spice mixture (6.72,5.80,4.91,4.51) compared to the control (6.49, 4.91, 4.07, 3.03) after 24hours, 6, 12 and 18 weeks respectively and were significantly different (p <0. 05) from the control. Total viable count from the study revealed that bacterial loads in smoked Clarias gariepinus were more affected by pepper and salt spice mixture than the control after 24hours and 18 weeks and this were significantly different ( p <0. 05) than control. The PV, TBA, FFA and TVB were lower in the treated groups compared to the control after 24 hours, 6, 12 and 18 weeks. These results indicated that using pepper and salt spice mixture may be useful in improving the shelf life and consumer acceptability of smoked Clarias gariepinus and it was concluded that 20% spice mixture would positively influence shelf life, reduce and prevent infections in smoked Clarias gariepinus.

Clarias gariepinus; Preservatives; Microbial safety; Organoleptic assessment; Proximate composition