Abstract
We investigated the effect of nisin and sucrose fatty acid esters on the growth of spoilage bacteria in fish-paste products. Nisin showed antibacterial activity against Bacillus subtilis and B. licheniformis vegetative cells and spores in liquid medium. Also, nisin exhibited a synergistic effect in combination with sucrose fatty acid esters (sucrose monolaurate and sucrose monopalmitate). The addition of nisin (12.5 μg/g) to fish-paste products suppressed the growth of B. subtilis and B. licheniformis during storage at 20°C and resulted in longer shelf-life of fish-paste products compared to control and fish-paste products with added potassium sorbate. In addition, the growth of spoilage bacteria was strongly inhibited by the combination of nisin (12.5 μg/g) and sucrose fatty acid esters (10 mg/g) in fish-paste products without starch. From these findings, we conclude that the addition of nisin is a potential alternative method for preventing spoilage caused by spore-forming bacteria in fish-paste products.