Table 4.
Thermal inactivation kinetics parameters at 52°C for Listeria monocytogenes 568, 568:ΔTreA, complemented mutant ΔTreA:pAM:TREOP, and 568/pAM401a
| Strain | βb | ASEc (β) | tcmd | ASE (tcm) | Logistic DL valuee (min) |
|---|---|---|---|---|---|
| 568 | 0.175 | 0.006 | 17.47 | 1.76 | 30.54 |
| 568:ΔTreA | 0.141* | 0.005 | 29.64* | 1.79 | 45.88* |
| ΔTreA:pAM:TREOP | 0.186 | 0.008 | 10.79* | 2.12 | 23.08 |
| 568/pAM401 | 0.174 | 0.012 | 15.35 | 3.66 | 28.49 |
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).