Table 4.

Thermal inactivation kinetics parameters at 52°C for Listeria monocytogenes 568, 568:ΔTreA, complemented mutant ΔTreA:pAM:TREOP, and 568/pAM401a

StrainβbASEc (β)tcmdASE (tcm)Logistic DL valuee (min)
5680.1750.00617.471.7630.54
568:ΔTreA0.141*0.00529.64*1.7945.88*
ΔTreA:pAM:TREOP0.1860.00810.79*2.1223.08
568/pAM4010.1740.01215.353.6628.49
  • a The inactivation kinetics was modeled using the modified Fermi distribution function (43). *, significantly different from value for the wild-type 568 for the same treatment (P < 0.05).

  • b β, inactivation rate parameter for the log-linear region of the death curve.

  • c ASE, asymptotic standard error.

  • d tcm, lag parameter prior to the region of maximum inactivation rate.

  • e DL, time for the initial log decline when a lag phase exists (equation 2).