TABLE 2.

Heat (59°C)-survival-parameter estimates for late-logarithmic-growth-phase (13-h) L. monocytogenes cells incubated at 37°C for 15 or 45 min in TPB at pH 7.3 or 12.0^e

Treatment time (min)	TPB pH (±0.1)a	Eqn.b	(1 − f) least heat-sensitive fraction	β2 − least heat-sensitive fraction (min−1)	β1 − most heat-sensitive fraction (min−1)	Pseudo r2c	Logistic D value (min)d
15	7.3	2	0.01	1.400 ± 0.124	2.510 ± 0.424	0.964	2.10
	12.0	2	0.02	0.788 ± 0.072	1.410 ± 0.245	0.951	3.73
45	7.3	2	0.01	1.490 ± 0.177	2.920 ± 0.817	0.923	1.97
	12.0	2	0.01	0.292 ± 0.031	1.450 ± 0.172	0.967	10.10

^aThe pH of TPB was adjusted using 1.0 N NaOH. 

^bParameter estimates were obtained by fitting survival data to the appropriate logistic equation (Eqn.) by nonlinear regression. 

^cCalculated as 1 − (residual sum of squares/corrected total). 

^dCalculated as D = (In19)/β₂. 

^ePer minute β values do not apply.