Listeria in the Dairy and Cold-Smoked Salmon Industries

1. Listeria in the Dairy and Cold-Smoked Salmon Industries Presented by Rebecca Robertson October 9, 2008

2. No Pathogens Allowed Determining the Risk of Pathogen Growth in Food Is the product frozen? Is the product safely distributed at room temperature? pH< 4.6? aw <0.85? Is the shelf-life < 10 days? Has product been specifically formulated and/or processed in some other manner to prevent the growth of pathogens?

3. No Pathogens Allowed Determining the Risk of Pathogen Growth in Food Is the product frozen? Is the product safely distributed at room temperature? pH< 4.6? aw <0.85? Is the shelf-life < 10 days? What barriers are there in soft cheese and cold-smoked salmon? Has product been specifically formulated and/or processed in some other manner to prevent the growth of pathogens?

4. Major risk factors leading to the occurrence of Listeria monocytogenes in smoked salmon* • Rotation of employees • Well-maintained facilities • Salting filets in vats (rather than small vats, trays or grates in stacks) L.M. Rorvik. (1997). Risk Factors for contamination of smoked salmon with Listeria monocytogenes during processing. Int. J. Food Micro. 37: 215 - 219

5. What else should we consider in a Smoked Salmon Plant? • Listeria monocytogenes can naturally be found on the surfaces of salmon • Listeria monocytogenes can be reduced during cold-smoking • Brine may be a source of Listeria monocytogenes

6. Important Processing Conditions for Cold-Smoked Salmon

7. What should we consider in a Dairy? • Soft cheeses are susceptible because they are conducive to the growth of Listeria monocytogenes during ripening and refrigerated storage • Listeria monocytogenes may be found in raw milk • The manufacturing of soft cheeses follow traditional processes

8. Important Processing Conditions for Dairies?

9. Food Safety Objectives for Listeria monocytogenes Category 1 Food (Foods that have been implicated in foodborne outbreaks) No Listeria monocytogenes detected in 50 grams of food Category 2 Food (Foods that support the growth of Lm) No Listeria monocytogenes detected in 25 grams of food Category 3 Food (Foods that do not support the growth of Lm) ≤ 100 cfu/g

10. From Health Canada: the recommendations below should be followed by high-risk individuals:

11. Design of Sampling Program • Establish baseline measurements • Identify sampling sites and frequency • Establish swabbing and analysis method • Establish Deviation Procedures

12. Design of Sampling Program • Establish baseline measurements using biased, investigative sampling techniques Data from this phase is used to select sampling sites, times, frequencies, and types of samples

13. Design of Sampling Program A Zone concept may be useful: Zone 1 Product Contact Surfaces Zone 2 Nonproduct contact surfaces in close proximity Zone 3 Nonproduct contact surfaces surfaces – further away Zone 4 Significantly distant from processing area

14. Monitoring of Zone 1 – example Monitor (Swabs and visual inspection) Positive Negative Troubleshoot (review/observe sanitation and physical conditions) Continue Monitoring Positive Negative Preventive/Corrective Action (dismantle equipment, intensify cleaning, repair physical damage) Negative Continue monitoring Verification Swabs Positive Negative Additional Actions, Test & Hold Finished Product Testing Continue monitoring

15. Monitoring of Zone 2 - example Monitoring Positive Negative Continue Monitoring Troubleshoot (review/observe sanitation and physical conditions) Preventive/Corrective Action (intensify cleaning, repair physical damage) Verify Action (reswab)

16. Monitoring of Zones 3 and 4 - example Monitoring Positive Negative Continue Monitoring Troubleshoot (review/observe sanitation and physical conditions) Preventive/Corrective Action (intensify cleaning, repair physical damage)

17. Important Reference ICMSF. (2002). Microorganism in Foods 7. Microbiological Testing in Food Safety Management. New York: Springer Science+Business Media. www.codexalimentarius.net/web/index_en.jsp