How to Control Listeria monocytogenes in Food Plants: Why, How, Where, What, and When to Look Jeffrey L. Kornacki, Ph.D. President and Senior Technical Director And Adjunct Faculty, Food Science, UGA www.kornackifoodsafety.com, Email:
[email protected]; 608-334-2254 Wisconsin Association for Food Protection meeting: Food Safety Industry Issues – Meeting Today’s Challenges Food Safety , June 11, 2014 Holiday Inn & Suties, Madision, WI
Reproduction by permission only
Why Are We Here?
Why Do We Care About Food Safety?
Illness / death 48 million cases, 128,000 hospitalizations, 3000 deaths per year1,2,3
Recalls-public exposure & lost market share Lawsuits -stricken individuals / class action Lawsuits-shorted customers
1www.cdc.gov/foodborneburden December 2010 2Scallan,
E., R.M. Hoekstra, F.J. Angulo, R.V. Tauxe, M-A. Widdowson, S.L. Roy, et al. 2011. Foodborne illness acquired in the United States—major pathogens. Emerg Infect Dis. 2011 Jan; [Epub ahead of print]
3Scallan,
E., R.M. Hoekstra, F.J. Angulo, R.V. Tauxe, M-A. Widdowson, S.L. Roy, et al. 2011. Foodborne illness acquired in the United States—major pathogens. Emerg Infect Dis. 2011 Jan; [Epub ahead of print]
Microbiological Risks Food Safety (continued)
Down time until contamination sites determined and eliminated and food safety system overhauled
Costs of repairs / modifications
Costs to remanufacture product
Insurance issues
Where Listeria and Salmonella fit into the big picture of Foodborne Illness
Illness: 1.) Norovirus (58%), 2.) nontyphoidal Salmonella (11%) Hospitalization: 1.) Non-typhoidal Salmonella (35%), 2.) Norovirus (26%) Death: 1.) Non-typhoidal Salmonella (28%), 2.) T. gondii (24%), 3.) Listeria monocytogenes (19%)
Scallan, E., R.M. Hoekstra, F.J. Angulo, R.V. Tauxe, M-A. Widdowson, S.L. Roy, et al. 2011. Foodborne illness acquired in the United States—major pathogens. Emerg. Infect Dis. 2011 Jan; [Epub ahead of print]
Deaths due to foodborne illness (est.)
Salmonella Listeria
31.0% 28.0% 21.0%
Toxoplasmosis
Other 5.0% E. coli 0157 Campylobacter Norovirus 7.0%
3.0% 5.0%
Source: Mead et al, 1999
6 Adapted from presentation by Art Liang, CDC at IAFP 2006 annual meeting in Calgary, AB
Estimated Annual Foodborne Disease From Selected Pathogens Bacterium
No. Total Illnesses
% Total Illnesses
% Hospitalized
Campylobacter
2M
14.2
17.3
5.5
99
Salmonella (non-typhoidal
1.3 M
9.7
25.6
30.6
553
2493
0.0
3.8
27.6
499
62,458
0.5
3.0
2.9
52
Clostridium perfringens
248,520
1.8
0.1
0.4
7
Staphylococcus
185,060
1.3
2.9
0.1
2
89,648
0.6
2.0
0.8
14
Listeria monocytogenes E. coli O157:H7
Shigella
% Deaths
No. Deaths
Source: Adapted from Mead, et al. 1999. Food-related illness and death in the United States. Emerging Infectious Diseases 5(5): 607-625, September-October
1Commondities
implicated in Foodborne Disease Outbreaks, 1998-2008, n=3641 Commodity
Percentage
Poultry
19
Finfish
19
Beef
12
Leafy
8
Pork
8
Mollusk
6
Fruits-Nuts
6
Dairy
5
Grains-Beans
4
Eggs
4
Other
9
Cheese-73 Outbreaks, 1678 illnesses, 187 hospitalizations, 3 deaths; 54% cheese from pasteurized milk, rest from unpasteurized milk Salmonella and Campylobacter in unpasteurized outbreaks
Adapted from presentation by Gould, L. H. 2012. CDC data on foodborne disease outbreaks associated with cheese, 8 1998-2008. January 18.
Possible contributing factors listed
Inadequate pasteurization
Poor sanitation
Insufficient separation between raw milk processing and packaging of finished product
Adapted from presentation by
9Gould, L. H. 2012. CDC data on foodborne disease outbreaks associated with cheese, 1998-2008. January 18.
Predicted US Listeriosis Cases on a Per Serving Basis (log scale)
Adapted from USDA_FSIS/ FDA-CFSAN/ CDC. 2003. Quantitative Assessment of Relative Risk to Public Health from Foodborne Listeria monocytogenes Among Selected Categories of Ready-to-Eat Foods. September.
10
DM = Deli meats; FNR = Frankfurters (not reheated); P= Pâté and Meat Spreads; UM= Unpasteurized Fluid Milk; SS= Smoked Seafood; CR = Cooked Ready-To-Eat Crustaceans; HFD = High Fat and Other Dairy Products; SUC = Soft Unripened Cheese; PM = Pasteurized Fluid Milk; FSC = Fresh Soft Cheese; FR = Frankfurters (reheated); PF = Preserved Fish; RS = Raw Seafood; F = Fruits; DFS= Dry/Semi-dry Fermented Sausages; SSC = Semi-soft Cheese; SRC = Soft Ripened Cheese; V = Vegetables; DS = Deli-type Salads; IC= Ice Cream and Frozen Dairy Products; PC = Processed Cheese; CD = Cultured Milk Products; HC = Hard Cheese.
Predicted US Listeriosis Cases/yr by Food Category (log scale)
DM = Deli meats; FNR = Frankfurters (not reheated); P= Pâté and Meat Spreads; UM= Unpasteurized Fluid Milk; SS= Smoked Seafood; CR = Cooked Ready-To-Eat Crustaceans; HFD = High Fat and Other Dairy Products; SUC = Soft Unripened Cheese; PM = Pasteurized Fluid Milk; FSC = Fresh Soft Cheese; FR = Frankfurters (reheated); PF = Preserved Fish; RS = Raw Seafood; F = Fruits; DFS= Dry/Semi-dry Fermented Sausages; SSC = Semi-soft Cheese; SRC = Soft Ripened Cheese; V = Vegetables; DS = Deli-type Salads; IC= Ice Cream and Frozen Dairy Products; PC = Processed Cheese; CD = Cultured Milk Products; HC = Hard Cheese.
Adapted from USDA_FSIS/ FDA-CFSAN/ CDC. 2003. Quantitative Assessment of Relative Risk to Public Health from Foodborne Listeria monocytogenes Among Selected Categories of Ready-to-Eat Foods. September. 11
Joint FDA/CDC/USDA Listeriosis risk assessment-some highlights and “draft guidance” from FDA, 20081 Highest risk foods: Support growth of L. monocytogenes. Lowest risk foods: Intrinsic or extrinsic factors that prevent growth of L. monocytogenes, Or Processed to alter the normal characteristics of the food. Examples: L. monocytogenes does not grow when: pH of the food < 4.4 Aw of the food < 0.92; or The food is frozen or formulated to prevent growth of Listeria Proposes a standard in these instances of 150 national or multistate & >1,000 state & local investigations
Since 2006, 13 newly recognized food vehicles that can transmit pathogens
Preliminary data
Source: Foodborne Disease Outbreak Surveillance System
Listeriosis (and selected illness to other foodborne disease hazards) compared to 1996-1998 (FoodNet Data)
What is enough? Testing?
GMP Audits? (Systems) – Personal experiences across 25 years
What About HACCP Verification Audits? (Tomato example)
So What is Missing?
The Environment is Critical “… cross contamination ...was mentioned as the most important factor relating to the presence of pathogens in prepared foods”1 Environmental contamination is the principle source of contamination of processed foods It is from the post-processing (post-CCPm) environment2 1Riej,
et al. 2005. Recontamination as a source of pathogens in processed foods-A literature review. ILSI. Quoting, Rocourt, J., et al. 2003. Present state of foodborne disease in OECD countries. WHO, Food Safety Department, Geneva.
2Kornacki,
J. L. 2009. The missing element in microbiological food safety inspection approaches, Part I. Food Safety Magazine. February / March.
Examples of Outbreaks Attributed to Environmental Contamination Product
Pathogen
Comment
Reference
Ice Cream
S. Enteritidis
Pasteurized ice cream mix in tanker truck previously used for transporting raw liquid eggs
Hennessy et al. (1996)
Infant formulae
S. Eealing
Contamination from the processing environment, insulation material of the drying tower
Rowe et al. (1987)
Soft cheese
S. Berta
Cheese ripening in buckets previously used for chicken carcasses
Ellis et al. (1998)
Cooked sliced ham
S.Typhimurium
Cooked ham placed into containers previously used for curing raw pork
Llewellyn et al. (1998)
Chocolate
S. Napoli
Possibly contaminated water used in double-walled pipes, tanks,
Gill et al. (1983)
Chocolate
S. Eastbourne
Contamination from the processing environment
Craven et al. (1975)
Butter
S. Eastbourne
Contamination from the processing environment
Lyytikainen et al. (2000)
Hot dogs
L. monocytogenes
Contamination from the processing environment
Anonymous (1999)
Canned salmon
C. botulinum
Contamination from the processing environment, cooling water
Anonymous (1984);Stersky et al. (1980)
Lasagna
S. aureus
Growth of S. aureus in the processing equipment, improper cleaning
Woolaway et al. (1986);Aureli et al. (1987)
Examples of Outbreaks Attributed to Environmental Contamination continued Product
Pathogen
Comment
Reference
Different foods
E. coli O157:H7
Contaminated meat grinder and equipment at retail level
Banatvala et al. (1996)
Chocolate milk
Y. enterocolitica
Probably during manual mixing of pasteurization milk and chocolate or contaminated chocolate syrup
Black et al. (1978)
Canned meat
S. Typhi
Use of non-potable water for can cooling
Ash et al. (1964); Stersky et al. (1980)
Crabmeat
S. aureus
Contamination during manual picking of cooked meat
Bryan (1980)
Canned mushrooms
S. aureus
Possible growth of S. aureus in the brine bath before canning
Hardt-English et al. (1990)
Flavored Yogurt
E. Coli O157:H7
Pump previously used for raw milk
Morgan et al. (1993)
Pastry
S. Enteritidis PT4
Equipment previously used for raw eggs or insufficiently cleaned piping and nozzles used for cream
Evans et al. (1996)
Yeasts
S. Műnchen
Contamination from the processing environment
Joseph et al. (1991
Pasteurized milk
S. Typhimurium
Possibly cross-connection between raw and pasteurized milk
Lecos (1986)
Pasteurized milk
E. coli O157:H7
Contamination from pipes and rubber seals of the bottling
Upton & Coia (1994)
Mexican type cheese
L. monocytogenes
Contamination from the processing environment
Linnan et al. (1988)
Microbial Growth Requirements Food (soil)
Water
Time
How To Look
Many tools Sponges Swabs Tongue depressors 1 - Ply tissues
Kornacki, J. L. 2010. How do I sample the environment and equipment, Chapter 7. In, J. L. Kornacki (Ed.), Principles of Microbiological Troubleshooting in the Industrial Food Processing Environment. Springer, New York. Pp. 125-136.
Sampling Supplies: What to bring Pre-sterilized Bags Sponges Swabs Scoops Tongue depressors Neutralizing buffer Gloves Extension rod Cutting devices (scissors, knives, box cutters etc.)
Sampling Supplies: What to Bring Duct tape Alcohol (wipes, etc.) Tools Sanitizer test strips pH strips Thermometer Laser pointer FLASHLIGHT! Kornacki, J. L. How do I sample the environment and equipment? Chapter 7. In, J. L. Kornacki (Ed.), Principles of Microbiological Investigation in the Industrial Food Processing Environment. Springer, New York. Pp. 125-136.
Additional helpers
Technical person – key role observe, coordinate activities
Assistant (swabber; set of eyes)
Scribe
Maintenance/repair personnel
Kornacki, J. L. Where do I begin the investigation? Chapter 6. In, J. L. Kornacki (Ed.), Principles of Microbiological Investigation in the Industrial Food Processing Environment. Springer, New York. Pp. 117-123.
High, Medium and Indirect Risks
High risk - as an area or practice which may directly contaminate the product, either continually or intermittently (in a direct measureable manner) Medium risk - similar to “high risk”, but mitigating factors (such as further heat processing) may reduce risk by and undetermined amount Indirect risk - any situation or condition (such as standing water) which potentially may contaminate product under certain conditions
When to Look Pre-operationally-Zone 1 and 2 Usually indicators (APC, Yeast, EB/coliforms, 1Esculin Hydrolysing Organisms (MOX1,3, HQA3), HTEB1,2,3, Establish a sanitation break point. Operationally/Post Operationally – Zone 3 & 4. Listeria spp. principally wet processing environments Salmonella principally in dry processing environments 1Kornacki,
J. L. 2011. Indicator organism assays: Chaos, confusion and criteria. Food Safety Magazine. February/March. J. L. 2010. IAFP Symposium S22. Food and Food Environment Test Considerations in View of Changing Regulations. (Organizer and Co-convener). Presentation entitled, “An Indicator Approach to Enteric Contamination of at Risk Foods.” August 1-4. Anaheim, CA. 3Kornacki, J. L. 2014. Kornacki, J. L. 2014. An environmental sampling approach to product risk assessment. Food Safety Magazine. February/March issue. 2Kornacki,
An Example of Site Specific Risk Assessment Frame Work (Salad Dressing)
Suggested Risk
Priority
Site
Comments/Observations/ Data
Recommendations
A chance to drill into the specifics
Parking Tickets Vs. Parking Permits Direct vs indirect approaches
HQA Enrichment and plating Experience in a complex environment (meat, poultry, seafood, vegetables, etc.)
Currently licensed laboratories: ABC Research, Gainesville, FL Food Microbiological Laboratories, Cypress, CA
Listeria monocytogenes PCR and culturally confirmed positives on 19 Samples Compared to HQA Enrichment with and without FAC and Streaking Onto Baird-Parker and Modified Oxford Medium (NH = No halo)
Listeria PCR negative results compared to HQA enrichment and streaking onto Baird-Parker and Modified Oxford medium
Inoculated Sponge Study
Relationship of Selected Microbiological Tests/Organisms APC HQA
Enterobacteriaceae
MOX
Listeria spp. LM
Coliforms HTEB
Salmonella B. cereus
Bacillus spp.
Development of a Risk Assessment Approach
Correlation of % Listeria spp. Isolated from Packaging Lines and Floors to RTE Meat
Lead to in-plant risk assessment concept
Tompkin, R.B., L.N. Christiansen, A.B. Shaparis, R.L. Baker, and J.M. Schroeder. 1992. Control of Listeria monocytogenes in processed meats. Food Australia 44:370-376 Kornacki, J. L. and J. B. Gurtler. 2007. Incidence and control of Listeria in food processing facilities, Chapter 17. In, E. T. Ryser and E. H. Marth (eds.), Listeria, listeriosis and food safety, 3rd ed. CRC Press, Taylor & Francis Group, Boca Raton, FL. Pp. 681-766.(see page 729).
Correlations of % Environmental to % Finished Product Contamination Smoked fish plant: Correlation of environmental L. monocytogenes to finished product (p