Incidence of Listeria monocytogenes in different food products commercialized i...

• Author(s): Mena, Cristina ; Almeida, Gonçalo ; Carneiro, Luísa ; Teixeira, Paula ; Hogg, Tim ; Gibbs, Paul A.
• Date: 2004
• Persistent ID: http://hdl.handle.net/10400.14/6709
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Subject(s): Listeria monocytogenes; Incidence in foods
• Document Type: Article
• Language: English

Description

Several types of food products on sale in Portugal, were examined for the presence of Listeria monocytogenes. Secondary enrichments, in Fraser broth, were analysed by the mini-Vidas LMO, enzyme-linked fluorescent immunoassay technique. Positive samples were confirmed by isolation on Oxford and PALCAM selective agars followed by biochemical characterization. Of 1035 samples, 72 (7.0%) were positive for L. monocytogenes, the majority being from raw products (milk, meat, fish, flour) although some heat-processed or fermented foods (ready-to-eat) were also positive. In Portugal, a predilection for fresh cheese was indicated as a potential risk for consumers.