Figure 4

Reduction of a S. enterica ssp. enterica contamination on fresh chicken breast fillet by salmocins. (a) Bacterial populations recovered from meat upon storage for various periods of time at 10 °C upon salmocin treatment (black bars, initial contamination level; white bars, carrier treatment; light grey bars, bacteriocin treatment SalE1a in concentration of 3 mg/kg meat; grey bars, bacteriocin treatment SalE1a + SalE1b + SalE2 + SalE7 in concentration of 3 + 1 + 1 + 1 mg/kg meat; dark grey bars, bacteriocin treatment SalE1a + SalE1b + SalE2 + SalE7 in concentration of 0.3 + 0.1 + 0.1 + 0.1 mg/kg meat) of contaminated meat by spray-application. Error bars indicate standard deviation of biological replicates, N = 4. Statistically significant reductions in bacterial contamination were found by assessment of viable bacterial counts obtained from salmocin-treated (individual SalE1a at an application rate of 3 mg/kg meat (p-values for comparison at 1 h, 24 h, 48 h and 72 h post treatment were <0.0001, 0.0012, 0.0137 and 0.0037, respectively) or salmocin blend consisting of SalE1a + SalE1b + SalE2 + SalE7 at an application rate of 3 + 1 + 1 + 1 mg/kg meat (p-values for comparison at 1 h, 24 h, 48 h and 72 h post treatment were <0.0001, 0.0012, 0.0136 and 0.0035, respectively) and salmocin blend consisting of SalE1a + SalE1b + SalE2 + SalE7 at an application rate of 0.3 + 0.1 + 0.1 + 0.1 mg/kg meat (p-values for comparison at 1 h, 24 h, 48 h and 72 h post treatment were 0.0002, 0.004, 0.0139 and 0.005, respectively) respectively), all in relation to carrier-treated meat samples showing efficacy of salmocin treatment. (b) Chicken breast trims used in (a).