ABSTRACT

The effectiveness of four (4) treatments such as garlic {AHium sativum), ginger {Zingiber officinale), turmeric {Curcuma ionga) and control (fish sample smoked without spice) in smoking of two (2) different fish species; Tilapia {Oreochromis niioticus) and Catfish {Ciarias gariepinus) was evaluated. The fish samples were beheaded, gutted, eviscerated, cut into chunks and washed with clean water and was taken for initial proximate analysis. The three samples were immersed in treatment solution and the processed fish were smoked with a traditional smoking kiln. Final proximate analysis were carried out to determine the moisture, protein, ash, lipid, crude protein, crude fibre and carbohydrate content and also microbial analysis were done to check the bacteria count in the samples. Organoleptic assessment were done using a questionnaire. Result shows that the moisture content in fresh Oreochromis niioticus (non-smoked fish sample used for initial analysis) was significant (p<0.05) from the control and treated samples (garlic, ginger and turmeric). In the treated samples, moisture content was highest in turmeric with the value (9.66+0.057c) followed by garlic (8.95+0.021e) and ginger had the least with the value (8.78+0.028e). The dry matter content was highest in ginger treated sample with the value (91.22+0.028a) and were significantly different from other samples (p<0.05). Result in Ciarias gariepinus shows that the moisture content in the fresh sample was significantly different (p<0.05) from the control and treated samples with value (70.47+0.021a) for the fresh sample. In treated sample turmeric had the highest moisture content with the value (8.53+0.106e). Ginger sample had the highest dry matter content with the value (91.48±0.106a) than in other treated samples. This signifies that the lower the moisture content, the higher the dry matter content. Microbial load count in Ciarias gariepinus was highest in the fresh sample (91.50+3.535a) followed by the control with the value (48.00+1.414b) but in treated samples the microbial count was highest in turmeric (35.00+ 1.414d) and least in ginger sample with the value (29.50± 1.414d). In Oreochromis niioticus, result shows that both the fresh and control samples had more microbial loads with the values (71.00+4.243a) and (40.50±2.121b) respectively. However, in the treated samples ginger had the least load count with the value (23.00+2.828c). Storage of smoked fish were carried out for 6 weeks. In Ciarias gariepinus the storage quality was high up to week 5 of storage while in Oreochromis niioticus; softness in texture, mouldiness and poor appearance were recorded from week 4. Statistical analysis using ANOVA was carried out. Effects with probability (p<0.05) were considered significant.