TABLE 4.

Inhibition at 4°C of L. monocytogenes (LM) by competitive-exclusion microorganisms (CEM) in biofilms formed on stainless steel coupons

CEM strain no.	L. monocytogenes or CEM count (log10 CFU/cm2) at daya:
	0			14			21			28			35
	LM only	LM + CEM	CEM only	LM only	LM + CEM	CEM only	LM only	LM + CEM	CEM only	LM only	LM + CEM	CEM only	LM only	LM + CEM	CEM only
141-1	2.6 ± 0.1	2.6 ± 0.1	6.4 ± 0.3	3.7 ± 0.1	2.2 ± 0.0	6.4 ± 0.6	4.5 ± 0.1	2.3 ± 0.1	7.0 ± 0.6	6.0 ± 0.5	2.3 ± 0.1	7.6 ± 0.4	6.8 ± 0.5	3.2 ± 0.1	7.9 ± 0.5
152	2.6 ± 0.1	2.6 ± 0.1	6.6 ± 0.4	3.7 ± 0.1	<1.7b	6.6 ± 0.2	4.5 ± 0.1	<1.7	7.3 ± 0.4	6.0 ± 0.5	2.7 ± 0.0	7.8 ± 0.1	6.8 ± 0.2	2.5 ± 0.0	7.8 ± 0.2
375-1	2.6 ± 0.1	2.6 ± 0.1	6.5 ± 0.2	3.7 ± 0.1	2.2 ± 0.1	6.2 ± 0.2	4.5 ± 0.1	2.2 ± 0.0	7.0 ± 0.3	6.0 ± 0.5	<1.7	7.3 ± 0.5	6.8 ± 0.4	2.4 ± 0.0	7.8 ± 0.7
C-1-92	2.6 ± 0.1	2.6 ± 0.1	6.3 ± 0.2	3.7 ± 0.1	<1.7	3.8 ± 0.3	4.5 ± 0.1	<1.7	3.9 ± 0.2	6.0 ± 0.5	<1.7	3.5 ± 0.2	6.8 ± 0.4	<1.7	2.5 ± 0.2
143-1	2.6 ± 0.1	2.6 ± 0.1	6.5 ± 0.2	3.7 ± 0.1	<1.7	5.9 ± 0.1	4.5 ± 0.1	2.2 ± 0.0	6.5 ± 0.1	6.0 ± 0.5	<1.7	6.9 ± 0.7	6.8 ± 0.2	3.0 ± 0.2	7.5 ± 0.3
C-1-152	2.6 ± 0.1	2.6 ± 0.1	6.5 ± 0.3	3.7 ± 0.1	2.0 ± 0.0	6.1 ± 0.2	4.5 ± 0.1	<1.7	6.4 ± 0.4	6.0 ± 0.5	2.5 ± 0.2	7.2 ± 0.4	6.8 ± 0.5	3.4 ± 0.2	7.4 ± 0.6

^aLM only, L. monocytogenes count in biofilm in which only L. monocytogenes bacteria were applied to coupons; LM + CEM, L. monocytogenes count in biofilm in which both L. monocytogenes and CEM were applied to coupons; CEM only, competitive-exclusion microorganism count in biofilm in which only CEM were applied to coupons.

^bMinimum detection limit by direct plating method (<1.7 log₁₀ CFU/cm²).