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Published on: January 13, 2017
Listeria monocytogenes in Irish Farmhouse cheese processing environments
Edward Fox1, Karen Hunt, Martina O'Brien
1Teagasc Food Research Centre, Moorepark, Fermoy, Co Cork, Ireland.
International Journal of Food Microbiology
|November 20, 2010
Summary
Listeria monocytogenes contamination is common in cheesemaking facilities. The farm environment, including raw milk and external areas, can be a source of contamination within the processing environment, potentially leading to cheese contamination.
Area of Science:
- Food Safety
- Microbiology
- Environmental Health
Background:
- Listeria monocytogenes (L. monocytogenes) is a significant foodborne pathogen.
- Contamination in cheesemaking facilities poses a risk to public health.
Purpose of the Study:
- To identify the sources, persistence, and transfer routes of L. monocytogenes contamination in cheesemaking facilities.
- To differentiate L. monocytogenes isolates to understand contamination pathways.
Main Methods:
- Sampling of 16 cheesemaking facilities over two years.
- Analysis of cheese, raw milk, processing environment, and external farm samples.
- Differentiation of L. monocytogenes isolates using Pulsed-Field Gel Electrophoresis (PFGE) and serotyping.
Main Results:
- 13 of 16 facilities had L. monocytogenes positive samples.
- 52 different pulsotypes were identified, with no overlap between facilities.
- Persistent L. monocytogenes strains were found at two facilities.
- Contamination rates: 6.3% milk, 13.1% processing environment, 12.3% external environment.
- L. monocytogenes from raw milk and external farm environments were found in the processing environment and occasionally on cheese.
Conclusions:
- The farm environment external to the processing area is a potential source of L. monocytogenes contamination in the processing environment.
- Understanding contamination routes is crucial for preventing L. monocytogenes in cheese production.
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