2005 Symposium Listeria hysteria

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2005 SymposiumListeria hysteria
Control of Lm onRTE Meat Products

• Ruby M Lee PhD

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Lm Milestones

• Named after Dr. Joseph Lister
• Ubiquitous soil, water, air, vegetation, animal
• 1900s Animal pathogen
• 1930s Human pathogen
• 1980s Significant foodborne pathogen
• 1990s Meat and poultry industry recalls of hot
  dogs, deli meats

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Very High Risk Food

• Deli meats
• Frankfurters (not reheated)

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High Risk Food

• Amount and frequency of consumption
• Frequency and level of contamination
• Ability of food to support growth
• Refrigerated storage temperature
• Refrigerated storage time

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Health CanadaPolicy on Lm in RTE Foods
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CDC Statistics
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High Risk Groups

• Infant
• Pregnant women and fetuses spontaneous abortions
  (2nd/3rd trimester) or stillbirth
• Immunocompromised hosts
• Elderly

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Infectious Doses
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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Cleaner raw products at receiving
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Food Safety Continuum
Farm
Slaughter
Processing
RTE

• Lethality Treatment

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Greatest Risk

• Lethality Treatment
  Packaging
• Greatest risk of recontamination from
  environment, equipment, people

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FSIS Risk Assessment Model

• How often does contamination occur
• 20 29 days
• How long does it last
• 9 20 days

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FSIS Risk Assessment Model

• Likelihood of detection
• 7x improvement
• Lot prevalence of Lm 2.2
• FCS prevalence for Listeria spp. 13.7
• Lot prevalence when FCS 15.7

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FSIS Risk Assessment Model

• Increased frequency of food contact surface
• Sanitation
• Testing
• Lower risk of listeriosis

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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Lethality Treatment Sanitation Program Listeria
Sampling Program Post-Lethality
Treatment Antimicrobial Agent/Process
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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Lethality Treatment Sanitation Program Listeria
Sampling Program Post-Lethality
Treatment Antimicrobial Agent/Process
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Listeria Sampling Program

• Food safety mission to produce safe, wholesome
  and unadulterated products
• Verify Sanitation SOP
• Satisfy customer specification (COA)
• Prevent publicized recalls

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Pilgrims Pride Recall

• Wampler Foods, Pilgrims Pride. PA. USA
• 2002
• One of the largest recalls in U.S. history
• 27.4 million lbs RTE turkey and chicken deli
  meats
• USDA matched Lm strain in the plant drains
• A spike of Listeria spp. in environmental
  sampling reports in summer.

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Pilgrims Pride in 2005

• Fortune magazine
• On the list of 100 fastest-growing U.S. companies
• The only food company on the list
• On the list of 500 largest U.S. companies
• On the most admired firm list in the U.S. in
  2003, 2004, and 2005

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Sentinel Site nFCS Program

• -
• Routine L. spp. Monitoring (RM) RM
• 9-
• Corrective Action
• Intensified L. spp. Monitoring
•   9-
• Corrective Action
• Lm Monitoring
•  
•  
•  
•  
•  
•  

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Sentinel Site FCS Program

• -
• Routine L. spp. Monitoring (RM) RM
• 9-
• CA Intensified L. spp. Monitoring
•   CCP 9-
• CA Intensified L. spp. Lm Monitoring
• Product Lm Testing
• Product Disposition Test and hold policy
  
•    
•  
•  
•  
•  

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FSIS FCS Program

• -
• L. spp. Monitoring (RM) RM
• -
• CA L. spp. Monitoring
•   3 Days - Release
• CA L. spp. Monitoring 3 Days
• 3-Day Product Lm Testing
• Product Disposition Hold policy
•  
•  
•  
•  
•  
•  

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Health Canada Lm Policy

• -
• 5 FCS comp 5n-FCS comp (RM) RM
• -
• CA 5 FCS 5n-FCS repeat
•   - Release
• CA Product Lm Testing
• Product Disposition
• Hold policy
•  
•  
•  
•  
•  
•  

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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Lethality Treatment Sanitation Program Listeria
Sampling Program Post-Lethality
Treatment Antimicrobial Agent/Process
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Post-Lethality Treatment

• Lethality treatment eliminates Lm
• Products can be re-contaminated by exposure
• Peeling
• Slicing
• Repackaging

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Post-Lethality Treatment

• Lm is a hazard reasonably likely to occur
• Hazard is controlled by a CCP in a HACCP plan
• Post-lethality treatment is validated to reduce
  or eliminate Lm
• gt 2 log reduction
• 1 - 2 log reduction

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Post-Lethality Treatment

• Pre-packaging treatment
• Radiant heating
• Listericidal lt0.85 water activity
• Post-packaging treatment
• Steam pasteurization
• Hot water pasteurization
• High pressure processing

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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Lethality Treatment Sanitation Program Listeria
Sampling Program Post-Lethality
Treatment Antimicrobial Agent/Process
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Antimicrobial Process

• Freezing is validated to suppress or limit Lm
  growth throughout the shelf life
• lt 1 log increase
• 1 2 log increase

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Antimicrobial Agent

• Antimicrobial agent is validated to reduce or
  eliminate, or suppress or limit Lm growth
  throughout the shelf life
• During formulation synergistic listeriostatic
  effect of lactates, acetates, diacetate
• On the finished product
• On the packaging material

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Antimicrobial Agent

• Purac Americas Optiform Listeria Control Model
• Predict Lm growth in cured meat during 4C storage
• Salt, moisture, Na/K lactate Na diacetate data
  input

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Antimicrobial Agent

• Coat growth inhibitors onto internal surface of
  cellulose casings
• nisin
• Antilisterial treatment is transferred to
  processed meat surface during thermal processing
• Antilisterial treatment remains active on
  processed meat after casing removal

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October 2003 Directive 10240.4Post-Lethality
Exposed RTE Products
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Validation

• The process of assuring that a defined set of
  control measures achieves appropriate control
  over a specific hazard in a specific food.
• International Commission for Microbiological
  Specifications for Foods

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Growth Limits for Lm
(ICMSF 1996)
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Validation

• Experienced food microbiologist
• Understand the growth limits of Lm
• Determine if a study is needed
• Study intrinsic properties of food
• Conduct microbiological growth modeling
• Design challenge study
• Growth study
• Lethality study

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Validation

• Design challenge study
• Growth study antimicrobial agent
• Lethality study post-lethality treatment

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Validation

• Strain selection
• 3 5 strains associated with product and
  outbreak
• Lm for lab study
• Listeria innocua for food processing facility.
• Resistance Listeria innocua gt Lm

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Validation

• Inoculum level
• Growth study 100 1,000 cfu/g
• Post-lethality study 104 106 cfu/g

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Validation

• Sample inoculation
• Stationary phase cells recontamination from
  environmental niches
• Surface inoculation log, sliced
• Inoculum simulates intrinsic properties of food
  pH, water activity, salt level, etc.

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Validation

• Growth study
• Normal
• Moderate abuse
• Worst-case scenario
• Holding
• Distribution
• Use

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Food Safety Continuum
Farm
Slaughter
Processing
RTE
Lethality Treatment Sanitation Program Listeria
Sampling Program Post-Lethality
Treatment Antimicrobial Agent/Process
Cleaner raw products at receiving
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2004 CDC Surveillance

• 8 Listeriosis cases / 1M population in 1990s
• 2.5 Listeriosis cases / 1M population by 2005
• 2.7 Listeriosis cases / 1M population in 2004

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RTE Meats
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Sharpen my Lm Saw

• cordially invites you to attend
• Listeria Control Workshop
• March 2, 2006