TABLE 3.

Comparison of standard plating and magnetic separation with CBD500-coated beads for detection of L. monocytogenes Scott A in artificially contaminated food samples

Food sample and initial contamination (CFU/g)Result obtained with following conditions for selective enrichment culturea
6 h24 h48 h
IDF/ISObCBD-MSIDF/ISOCBD-MSIDF/ISOCBD-MS
Sliced iceberg lettuce
    0
    0.1+++++++++++
    1++++++++++++
    10+++++++++++++
    100+++++++++++++
Camembert soft cheese
    0
    0.1++++++
    1++++++++
    10++++++++++++
    100+++++++++++++++
Red smear cheese
    0
    0.1++++++
    1++++++++++++
    10+++++++++++++
    100+++++++++++++
Smoked salmon
    0
    0.1++++
    1+++++++
    10+++++++++++++
    100+++++++++++++++
Minced meat
    0
    0.1
    1++++++
    10++++++++
    100++++++++++++++
Turkey breast
    0
    0.1++++
    1++++
    10++++++++
    100++++++++++++
Milk (pasteurized)
    0
    0.1++
    1+++
    10+++++++++
    100++++++++++++++++
  • a The number of plus signs indicates the number of typical Listeria colonies on Oxford agar as follows: +, 1 to 10 colonies; ++, 10 to 50 colonies; +++, more than 50 colonies.

  • b See Materials and Methods for details.