keywords: Clariasgariepinus, Lophiraalata, microorganisms, nutritional, PAHs, smoked
The study investigated the effects of smoking Clariasgariepinus with Lophiraalata wood on the nutritional qualities, chemical composition and Polycyclic Aromatic Hydrocarbon levels (PAHs) when stored for 28 days. For organoleptic qualities, only the taste values of the salted samples scored significantly higher (p<0.05) than the unsalted sample till day 14. All the proximate composition except fibre and carbohydrate of the smoked samples were significantly different from the fresh sample. Storage resulted in no significant change in all the proximate composition of the smoked samples except carbohydrate which increased significantly with storage. Mineral composition varied significantly between fresh and smoked samples except calcium. Storage did not significantly affect the concentrations of the minerals except sodium which decreased. There were differences in the values of concentrations of sodium, potassium and calcium in the salted and unsalted samples during storage. Mould was observed on day 14 in salted and unsalted samples with no significant difference (p>0.05). Microbial infestation occurred from first week in both samples and it increased significantly from the 21st day of storage. No insect infestation was observed. The microorganisms detected included Aspergillus spp., Fusarium spp., Saccharomyces spp., Penicillium spp., Staphylococci aureus, Staphylococci lentus, Klebsiella pneumoniae, Escherichia coli and Kocuriarosea. Forty three PAHs were detected in salted samples and 23 in unsalted samples, only in salted samples was Anthracene, a carcinogenic PAH, detected at low level of 0.57 μg kg-1 which poses no health risk to consumers. Thus, this study provided a possible application of L. alata as safe wood for smoking fish.
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