TABLE 4.

Growth kinetics values^a for Salmonella serovar Enteritidis, E. coli O157:H7, and L. monocytogenes in mixed cultures set up in SEL

Expt	Organism (CFU/ml)b	EGR (log10 CFU/ml/h)	GT (h)	LPD (h)	MPD (log10 CFU/ml)
I	Salmonella serovar Enteritidis (1)	0.82 ± 0.10	0.84 ± 0.10	3.64 ± 0.58	7.66 ± 0.08
	E. coli O157:H7 (1)	1.10 ± 0.11	0.68 ± 0.07	3.21 ± 0.42	8.01 ± 0.10
	L. monocytogenes (1)	0.72 ± 0.06	0.96 ± 0.08	3.48 ± 0.33	6.89 ± 0.05
II	Salmonella serovar Enteritidis (10)	1.04 ± 0.06	0.67 ± 0.04	2.70 ± 0.24	7.11 ± 0.09
	E. coli O157:H7 (1,000)	0.96 ± 0.09	0.72 ± 0.07	3.02 ± 0.41	8.58 ± 0.14
	L. monocytogenes (1)	0.71 ± 0.07	0.98 ± 0.10	3.70 ± 0.38	4.28 ± 0.09
III	Salmonella serovar Enteritidis (1)	0.65 ± 0.05	1.07 ± 0.08	2.67 ± 0.53	6.25 ± 0.19
	E. coli O157:H7 (10)	1.00 ± 0.09	0.69 ± 0.06	3.56 ± 0.24	5.71 ± 0.09
	L. monocytogenes (1,000)	0.52 ± 0.04	1.33 ± 0.10	3.01 ± 0.61	8.44 ± 0.09
IV	Salmonella serovar Enteritidis (1,000)	0.79 ± 0.07	0.88 ± 0.08	2.17 ± 0.54	9.33 ± 0.18
	E. coli O157:H7 (1)	NDc	NAd	NA	NA
	L. monocytogenes (10)	0.47 ± 0.02	1.46 ± 0.08	1.75 ± 0.49	6.00 ± 0.06

^aThe growth kinetics values for the three pathogens in mixtures were extrapolated from data from Fig. 2 by using the Gompertz equation (47). Values are expressed as means ± SDs.

^bThe numbers in parentheses indicate the initial inoculation levels for the given experiment.

^cND, not determined. Counts of E. coli CFU in the mixture could not be determined because of the overgrowth of Salmonella on E. coli-selective CT-SMAC plates (see the text for a detailed explanation).

^dNA, not applicable.