Production and Physicochemical Evaluation of Lemon Grass and Bay Leaf Extract as Natural Preservatives in Smoked African Catfish

This study evaluated the effect of lemongrass (Cymbopogon citratus) and bay leaf (Laurus nobilis) extracts, individually and in combination, on the shelf stability of smoked African catfish (Clarias gariepinus) during 28 days of storage. The treatments were assessed for changes in water activity, thiobarbituric acid (TBA), peroxide value (PV), free fatty acids (FFA), total viable counts (TVC), and mould growth. Results showed that water activity, TBA, PV, and FFA increased progressively across all samples during storage. However, fish treated with the combination of lemongrass and bay leaf consistently exhibited significantly lower values (p < 0.05) compared to the untreated control. Similarly, microbial and mould growth were markedly reduced in the extract-treated groups, with the combined treatment being most effective. The findings demonstrate that lemongrass and bay leaf extracts, especially when applied together, can effectively retard lipid oxidation and microbial proliferation, thereby improving the storage quality and extending the shelf life of smoked catfish. Keywords: African catfish, lemongrass, bay leaf, preservatives, shelf life, microbial quality