Bacteriostatic potential of nisin and sesamol combination against Listeria monocytogenes in chilled raw tuna fillets

Abstract

Chilled tuna fillets are easy to be contaminated by Listeria monocytogenes, which is an important risk factor for the outbreak of foodborne diseases. Nisin (NS) in combination with sesamol (SE) has showed to have the ability to inhibit the growth of L. monocytogenes in bacterial culture-medium, however, their bacteriostatic effect in actual food model has been not evaluated. Therefore, in this study, the combined effect of NS and SE on the growth of L. monocytogenes in yellowfin tuna fillet (Thunnus albacares) which was stored at constant and fluctuating temperatures were evaluated. The results showed that the combined use of NS (25 μg/mL) and SE (1.0 mg/mL) significantly reduced the growth potential of L. monocytogenes to 1.1–3.2 log10 CFU/g compared with the control group at constant and fluctuating 10 °C. The combined treatment of NS and SE delayed the lipid oxidation activity and increased the catalase activity and glutathione peroxidase activity of tuna fillets, but did not significantly change the texture and color characteristics of tuna fillets. These results indicated that the combined of NS and SE may be a promising technology to reduce L. monocytogenes pollution and maintain the physical and chemical properties of tuna fillets products.