LAUSR

ABSTRACT The present study was conducted to investigate the inhibitory effect of alginate coating incorporated with Zataria multiflora Boiss essential oil (ZEO) and lactoperoxidase system (LPOS), individually and in combination, in order to control inoculated Listeria monocytogenes and Escherichia coli O157:H7 in rainbow trout fillets during 16days of storage at 4°C. The antibacterial activity of ZEO was evaluated against Listeria monocytogenes and E. coli O157:H7 through determination of minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). In vivo study was performed by inoculating four strains of L. monocytogenes as culture cocktail and one strain of E. coli O157:H7 on trout fillets for their survival evaluation during the 16-day storage. Results indicated that ZEO and LPOS, when used in combination in alginate solution, had a stronger effect on the control of mentioned bacteria in trout fillets; however, their individual use could significantly inhibit their growth, when compared to the control. Moreover, it has been implicated that alginate coating, when used with no antimicrobial agent, had a supportive effect on the growth of these pathogenic bacteria. Therefore, the application of alginate coating containing ZEO and LPOS is recommended in foods, especially fish and fish products.