FIG. 6.

Assessment of cellular damage of L. innocua by flow cytometry after various high-pressure-low-temperature treatments. (a) Control, viable cells; (b) thermal treatment at 95°C, complete inactivation; (c) cells frozen to −40°C for 1 h without pressure treatment, inactivation according to results shown in Fig. 5; (d) treatment of ice at −45°C, 300 MPa, 0 min (phase transition to ice III), log (N/N₀) = −2.9; (e) treatment of ice at −45°C, 300 MPa, 5 times for 0 min (5 times repeated phase transition to ice III), log (N/N₀) = −4.2; (f) treatment of ice at −25°C, 300 MPa, 0 min (phase transition to ice III including partial thawing), log (N/N₀) = −2.6; (g) treatment at 0°C, 200 MPa, 5 min (in liquid conditions), log (N/N₀) = −0.6; (h) treatment at 0°C, 300 MPa, 15 min (in liquid conditions), log (N/N₀) = −2.8; (i) treatment at −45°C, 200 MPa, 10 min (treatment of ice I without phase transition), log (N/N₀) = −0.6. The inactivation results correspond to the inactivation determined for the specific sample which was used for flow cytometry.