Listeria Contamination in Milk-Processing Chain and Proficiency in Listeria monocytogenes Decontamination of Small-Scale Milk Retailers

Table 3

Concentration (CFU/mL) of bacteria, growing on BHI agar after treatment.

L. monocytogenes added in milk (CFU/mL)	Time^a	Processes^b
		1	2	3	4	5
10	T1	15	0	0	0	0
	T2	0	10	0	0	10
10^3	T1	0	15	0	15	0
	T2	0	0	5	5	75
10^5	T1	0	5	0	0	0
	T2	0	0	0	0	5

^aT1: post-treatment, T2: 30 min post-treatment. ^b1: using double boiling until bubbles formed, 2: using double boiling until a film layer formed, 3: using double boiling for 1–2 min, 4: using direct heating until bubbles formed, and 5: using direct heating until a film layer formed.