Inactivation kinetics of L. innocua NCTC 11289 at different electric field strengths. Symbols: ■, 2.0 to 2.1 V/μm; ⧫, 2.3 to 2.5 V/μm; ●, 2.7 to 3.0 V/μm; ✶, 3.2 to 3.5 V/μm; ■, 3.6 to 3.9 V/μm. The pH of the treatment medium was 5, the conductivity was 0.51 S/m at an inlet temperature of 40°C, and the pulse length was 3.9 μs. The inoculum contained 1.4 × 106 CFU/ml. The results are the means of data from two experiments, and standard deviations are indicated by error bars.