Inhibition and preservation effect of compound antibacterial agent on Listeria monocytogenes

To study the combined effect of lysozyme, glycine and sodium acetate on Listeria monocytogenes.The response surface methodology was used to determine the optimal combination of antibacterial agents.The effects of the calculated combinations of antibacterial agents were evaluated on the preservation of raw salmon. The bacterial count, p H, 2-thiobarbituric acid ( TBA) content and total volatile basic nitrogen ( TVB-N) content were measured to determine the changes in the quality of salmon during cold storage.The results showed that the optimal concentrations of lysozyme, glycine and sodium acetate were 0.6, 6.4 and4.9 g/L, the inhibition rate was 80% ± 0.23%. The compound bacterial agent group's bacterial count, pH, TBA contents and TVB-N was 5.56 lg CFU/g, 4.65 lg CFU/g, 6.78, 1.048 mg MDA/kg, 18.03 mg N/100 g in the seventh day.These indicators were much lower in the compound bacterial agent group than in the control, and the sensory scores were higher for raw salmon treated with the compound bacterial agent than for the control. This compound bacterial agent may effectively extend the shelf life of raw salmon by approximately two days.