Comparison of three polymerase chain reaction-based methods for the detection of Listeria monocytogenes in food

Three PCR-based methods for the detection of Listeria monocytogenes in food (BAX for Screening, Probelia and a method according to Kaclikova et al. (2003) were compared on the basis of the determination of detection limits for 15 artificially contaminated food products. Detection limits of all methods for all samples were 10(0) cfu per 10 g, with the exception of three cheese samples which did not produce valid results because of the inhibition of Probelia PCR. Detection limits for nonviable L. monocytogenes cells were sufficiently high (greater than or equal to 10(9) cfu per 10 g) for BAX and the method according to Kaclikova et al. (2003), but considerably low (less than or equal to 10(6) cfu per 10 g)for Probelia. The results demonstrate that BAX for Screening as well as the Kaclikova et al. (2001) method fulfill the sensitivity requirements for a rapid alternative method for the detection of L. monocytogenes in food, which would be equivalent to the standard method EN ISO 11290-1.