Characterization of Listeria monocytogenes isolated from production lines of fresh and cold-smoked fish

M. Vaz-Velho*, G. Duarte, J. McLauchlin, P. Gibbs

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    28 Citations (Scopus)


    Aims: The aims of this study were to characterize strains of Listeria monocytogenes isolated from cold-smoking fish plants to establish possible routes of contamination through the processing chain. Methods and Results: Listeria monocytogenes from fresh fish suppliers, raw materials, factory sites and finished products isolated in Portugal (162 isolates) and England (28 isolates) were characterized by serotyping, phage typing, tetracycline, cadmium and arsenic resistance, and plasmid profiling. On the basis of serotyping and phage typing, the isolates were categorized into eight groups. Although cultures within some of the groups could be further differentiated on the basis of plasmid profiling and cadmium and arsenite typing, consideration of all typing data predominantly clustered together isolates from a single location. L. monocytogenes strains: from fresh salmon suppliers were not found in the processing lines; from fresh salmon from different locations differed; and from the water where salmon trout were farmed differed from those isolated from the fish samples. Significance and Impact of the Study: No clear source or route of contamination in the cold-smoked processing chain could be established; however, these results highlight the complexity in tracking this bacterium through food chains.

    Original languageEnglish
    Pages (from-to)556-562
    Number of pages7
    JournalJournal of Applied Microbiology
    Issue number3
    Publication statusPublished - 2001


    Dive into the research topics of 'Characterization of Listeria monocytogenes isolated from production lines of fresh and cold-smoked fish'. Together they form a unique fingerprint.

    Cite this