Keywords
Smoked
African catfish
Clarias gariepinus
fatty acids composition
Abstract
The effects of smoking and storage on the fatty acids composition of smoked C. gariepinus were determined. Smoked C. gariepinus were produced using traditional smoking kiln (steel drum kiln) and an improved smoking kiln by Nigerian Institute for Oceanography and Marine Research (NIOMR). The smoked C. gariepinus were packed in polythene bags and transported to Matis Research Laboratory, Iceland for analysis. The smoked C. gariepinus were stored in simulated storage conditions similar to that of Lagos, Nigeria for 12weeks.The total fatty acids composition of the smoked C. gariepinus oil during the storage periods ranged between 86.05% to 93.22% and 84.23% to 91.41% for traditional and improved smoked C. gariepinus respectively. The saturated, monounsaturated and polyunsaturated fatty acids of the freshly smoked C. gariepinus oil were 31.47%, 35.50%, 26.25% and 32.8%, 34.9%, 23.71% of the total fatty acids for the traditional and improved smoked C. gariepinus respectively. Smoking has no significant (P>0.05) effect on the total fatty acids composition of the oil but there were significant (P< 0.05) reduction on total fatty acids composition of the smoked C. gariepinus oil from both smoking kilns after 8th week storage period. The smoked C. gariepinus oil is a rich source of Omega-6 (n-6) and omega-3 (n-3) fatty acids with n-6 to n-3 ratio of between 3.03 and 4.07 during storage. Smoking at high temperature up to 180oC and long period storage had significant effect (P< 0.05) on the polyunsaturated fatty acids especially on the concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), omega-3 fatty acids which are essential fatty acids that are beneficial to human health.
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