Inactivation of Escherichia coli by Carbon Dioxide under Pressure

Authors

  • P. BALLESTRA,

    1. The authors are with the Laboratoire Génie biologique et Sciences des Aliments, Université Montpellier II, 34095 Montpellier, France.
    Search for more papers by this author
  • A. ABREU DA SILVA,

    1. The authors are with the Laboratoire Génie biologique et Sciences des Aliments, Université Montpellier II, 34095 Montpellier, France.
    Search for more papers by this author
  • J.L. CUQ

    1. The authors are with the Laboratoire Génie biologique et Sciences des Aliments, Université Montpellier II, 34095 Montpellier, France.
    Search for more papers by this author

ABSTRACT

Thermal inactivation of Escherichia coli was studied under CO2 pressures of 1.2, 2.5, and 5 MPa at 25, 35, and 45°C. Two phases were observed in the destruction curves. The earlier stage was characterized by a slow rate of inactivation, which increased sharply at the later stage. An increase of pressure and/or temperature enhanced the antimicrobial effects of CO2 under pressure. The effects on cell structure were studied by scanning electron microscopy and the specific mechanism of action appeared to be related to enzyme inactivation.

Ancillary