Listeria monocytogenes in a frozen vegetable processing environment

Listeria monocytogenes isolates from a frozen vegetable processing environment were subtyped and in-house clones were identified based on MLST-ST, cgMLST-CT and SNP data. Further, comparative genomic analyses and phenotypical characterization of the growth ability and survival under cold stress and multiple freeze-thaw cycles were performed. The study demonstrates, that tracing contamination sources, identification of transmission routes and identification of in-house clones by using WGS data is a powerful tool to improve food safety in food processing environments.