FIG. 3.

Reductions in viable numbers of wt L. monocytogenes (▴) and AK01 (▪) after exposure to different pressures for 20 min at 20°C. Cells were grown in BHI broth at 30°C with shaking (160 rpm). (A) Cells were harvested in mid-exponential phase and resuspended in ACES buffer before treatment. The detection limit was a 7-log-unit reduction of the viable counts, which was exceeded by the wt at 450 MPa and by AK01 at 500 MPa. (B) Cells were harvested in stationary phase and resuspended in ACES buffer before treatment. The detection limit was an 8-log-cycle reduction of the viable counts, which was exceeded by the wt at 500 MPa and by AK01 at 600 MPa. (C) Cells were harvested in mid-exponential phase and resuspended in semiskim milk before treatment. The detection limit was a 7-log-cycle reduction of the viable counts, which was exceeded by the wt at 400 MPa, and by AK01 at 500 MPa. Experiments were performed in duplicate and error bars represent standard deviations.