Inhibition of Listeria monocytogenes in dairy products using the bacteriocin-like peptide cerein 8A.

The efficacy of the antimicrobial peptide cerein 8A to control the development of Listeria monocytogenes in milk and soft cheese was investigated. The addition of 160 AU ml(-1) cerein 8A to UHT milk resulted in a decrease of 3 log cycles in viable cells within the 14-day period at 4 degrees C. The viable counts of L. monocytogenes in pasteurized milk samples containing cerein 8A was lower than those observed in controls without bacteriocin. Addition of cerein 8A to Minas-type soft cheese caused a delay in the start of exponential growth phase, although similar counts were observed after day 6. When cerein 8A was used to control cheese surface contamination by L. monocytogenes, a decrease of 2 log cycles in viable counts of cerein-treated samples was observed during 30 days at 4 degrees C. This antimicrobial peptide shows potential use as a biopreservative for application in dairy products.