UWIC How Clean is Clean : Does it Matter ? Prof Chris Griffith Technical Director Von Holy Consulting Emeritus Professor Cardiff School of Health Sciences

UWIC

How Clean is Clean : Does it Matter ?How Clean is Clean : Does it Matter ?

Prof Chris GriffithProf Chris Griffith

Technical Director Von Holy Consulting Technical Director Von Holy Consulting

Emeritus Professor Cardiff School of Health Sciences Emeritus Professor Cardiff School of Health Sciences

Copyright © Prof Chris Griffith, UWIC2009

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Contents Contents

• Cleaning , Soil and Disinfection

• Allergens , biofilms and food safety

• Possibilities after cleaning

• Testing surface cleanliness

• How clean is clean ?

• Surface Testing and End product testing

Copyright © Prof Chris Griffith, UWIC 2006

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Cleaning

• Removal of soil

CleaningCleaning

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Soil Soil

• Matter out of place

• Organic soil –carbohydrates,proteins,lipids

• Mineral salts

• Other chemical soils-lubricants , metal oxides

• Associated microorganisms


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Cleaning

• Removal of soil

Disinfection

• Destruction or removal of microorganisms

Aim: to reduce to an acceptable level - little or no risk

CleaningCleaning

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Why is cleaning important ?• Food Safety --–chemical and microbiological l• Chemical residues -potential allergen

contamination ,contribute to biofilms• Residual microorganisms increase the risk of

foodborne disease• Residual moisture increases chances of

biofilm formation, microbial survival and transfer

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Food AllergiesFood Allergies

• Allergens– Normally proteins– Cause an IgE related immune response– Food often more than 1 protein

• Most reactions mild BUT anaphylaxis

• Only very small amounts needed


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Allergen Clean

• Clean to a level that removes residual allergenic protein from the product zone and adjacent areas to prevent cross contamination to subsequent product runs

• Links to quantity in food and quantity to trigger a reaction

How Clean is Clean: Allergens

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“Aggregation of microorganisms and their associated extracellular substances, actively attached to, growing and multiplying on a surface”

“Complex consortium of microorganisms enmeshed within an extracellular matrix”

What is a Biofilm?What is a Biofilm?

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Residual Microorganisms in the Food Production Environment and Food

Safety/Quality

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Surface Counts and Product Contamination Surface Counts and Product Contamination

• 4 yr Listeria monocytogenes study –JFP 2008

• 46% product isolates and 41% surface

• Persistent strains even after cleaning /dis infection –2 year period

• Strains on gloves /floors


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After closure of dairy A , approximately 100 additional environmental and product samples were collected from the dairy's processing facility and adjacent retail store on January 2, 2008.

One environmental swab from a floor drain in the finished product area, one skim milk sample, and seven flavored milk samples tested positive for L. monocytogenes and matched the outbreak strain by PFGE using the two restriction enzymes.

Outbreak of Listeria monocytogenes Infections Associated with Pasteurized Milk from a Local Dairy - Massachusetts, 2007MMWR Weekly, 10th October 2008 / 57(40);1097-1100

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The dairy’s records indicated the pasteuriser met standards for time/temperature and flow rate . They did not have an environmental monitoring programme . Contamination with the outbreak strain was found in close proximity to areas where hoses were used to clean equipment The milk plant was closed due to the financial burden

Outbreak of Listeria monocytogenes Infections Associated with Pasteurized Milk from a Local Dairy - Massachusetts, 2007MMWR Weekly, 10th October 2008 / 57(40);1097-1100

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Lm detected in 70(3.5%)env swabs and 16(7.4% ) product from Swiss sandwich plant. Of the 86 isolates 93% were serotype 1/2a with 6 genetic profiles . 78% belonged to one genotype found on slicers , conveyors, tables,bread feeding machine salmon, and egg sandwiches . These strains persisted for more than 9 months on slicers and conveyors . Revision of cleaning programmes solved the problem . Emphasizes impt of env monitoring to identify potential contamination problems and as early warning

Food Control April 2010

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Examples of Lm Plant Persistence by ProductExamples of Lm Plant Persistence by Product

Cheese 11month – 7 years

Fish months – 4 years

Meat months – 5 years

Poultry 12 years

Tompkin Journal of Food Protection

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Maple Leaf Plant Reopens after Listeria Outbreak


• 20 Deaths and estimated Cost of $20 m –Aug /Sept 2008• CEO said the slicing equipment at the plant will now be subject to stricter cleaning and testing , including disassembling

The CEO said the machines had been cleaned on a daily, weekly and monthly basis but it wasn’t until the machines were disassembled that they found the areawhere the bacteria had become embedded

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Salmonelllosis

Salmonella Enteritidis infections associated with a contaminated immersion blender, New Hampshire, 2009

This outbreak of Salmonella Enteritidis was caused by a Salmonella-contaminated immersion blender. A malfunctioning blender shaft seal is suspected to have resulted in poor cleaning leading to contamination of the products prepared using the blender.

Copyright © Prof Chris Griffith, 2009

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A A BIGBIG Case of Recontamination! Case of Recontamination!

USA 1994, 224,000 customers suffered Salmonella food poisoning from eating ice-cream due to poor cleaning of bulk transporters.

Tolley January, 1998


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Surface Cleanliness and Ice Cream Surface Cleanliness and Ice Cream Contamination Contamination

• Enterobacteriaceae should be largely destroyed by Pasteurisation

• Studies in UK 15% Ireland 6.5 % : Spain 47% were unsatisfactory with some counts in excess of 106


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Characteristics of 4 Most Important Characteristics of 4 Most Important Emerging PathogensEmerging Pathogens

ID X Cont Severity ID X Cont Severity

STEC Low Yes Severe

Lm Low * Yes Severe

Campylobacter Low Yes Moderate

Norovirus Low Yes Mild


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Importance of the food environment Importance of the food environment

“if an organism is found in the food environment there is a 70% chance of it getting into the food.”

IAFP Rome 2007

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Why cleaning is important

• Food Safety --–microbiological and chemical

• Shelf life

• Legal or other requirement

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Requirements for Cleaning :Legislation Requirements for Cleaning :Legislation EU Regs 852/2004EU Regs 852/2004

• Food Premises are to be kept clean and maintained in good repair and condition.

• Layout, design and construction

—permit adequate cleaning and disinfection

---protect against accumulation of dirt

• Cleaning agents and disinfectants are not to be stored in areas where food is handled


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Dubai Municipality Admin Order 20Dubai Municipality Admin Order 20

• Chapter 5 Requirements relating to Design Facilities and Operation

• Chapter 7 Requirements relating to Control of Food Storage and Cross Contamination

• Chapter 9 Guidelines for Cleaning and Disinfection


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Section 4:

4.9 Hygiene and HousekeepingCleaning procedures in place

Trained Personnel

Cleaning chemicals fit for purpose

Cleaning practices to minimise risk of cross contamination

Effectiveness of cleaning verified and recorded

Procedures revalidated

BRC Global Standard for Food Safety 2008BRC Global Standard for Food Safety 2008


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ISO 22000:ISO 22000:

• Guidance and workbook: Sanitation and cleaning.

• All aspects appropriately cleaned and disinfected on a regular basis.

• Well organised hygiene cleaning programme

• Defined standard of results.


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In Addition to Food Safety and Legality:• Pleasant and safe work environment (removes dirt and grease)• Auditor/ customer confidence (promotes favourable image)• Aids pest control (removes food and pests easier to see)• Increased shelf life and equipment performance • Reduction in:

– Food wastage Surface deterioration– Customer complaints Wear and tear– Physical contamination

Other Reasons Why Cleaning is ImportantOther Reasons Why Cleaning is Important


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What should a surface beWhat should a surface be like after cleaning ? like after cleaning ?

ANDANDHow Clean is Clean ?How Clean is Clean ?

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• Detects microorganisms and food residues with sufficient sensitivity

• Works equally well on wet and dry surfaces• Repeatable / Reproducible• Easy to use• Rapid• Cheap• Foolproof / recordable

How to Test for Cleanliness:How to Test for Cleanliness:Characteristics of an Ideal MethodCharacteristics of an Ideal Method

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Assessing CleanlinessAssessing Cleanliness

• No ideal method

• Any testing usually better than none but limitations recognised

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MicrobiologyMicrobiology

• No accepted standard / optimum method

• ISO 18593

• Highly variable results

Moore G and Griffith, C.J. (2007) Problems Associated with Traditional Hygiene Swabbing: The Need forStandardisation. Journal of Applied Microbiology; 103: 1090-1103

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ISO 18593 – Surface Sampling TechniquesISO 18593 – Surface Sampling Techniques


• Covers swabbing and contact methods• Swabbing diluent• Clean and disinfect after sampling• Sponges / cloths 100cm2

• Lot of variability allowed

• Low temperature swab transport 1-4C < 24hrs

• Contact plate 4 hours• Results used for “trend analysis”• Use of Rt sampling pattern• Contact plate not recommended for pathogens

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Microbiology: ConsiderationsMicrobiology: Considerations

• Is useful as part of an integrated approach

• What do you need to know

– Cleaning or contamination

• General contamination: presence/absence of pathogens

• Nature / shape of surface

• Direct/ Indirect contact

• Care with wetting solution if swabbing

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“In isolation visual assessment is not a good indicator of surface cleanliness”

Griffith, 2005 Handbook of Hygiene Control in the Food Industry

Visual Assessement Visual Assessement


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Relative Merits of Component ResiduesRelative Merits of Component Residues

• Universality - wide range foods

• Quantity in food

• Sensitivity of Test

• Other– cost – time taken– simplicity

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Non Microbial: Food Component Residues - Non Microbial: Food Component Residues - Sole or CombinationSole or Combination

• ATP

• Protein

• Reducing Sugar

• Other

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• ATP=Adenosine Triphosphate

• Residual surface Soil- blood , faeces, cells etc contain ATP

• ATP on surface converted into LIGHT

• Light measured in a luminometer

• More light =more residual surface soil

• More residual surface soil less effective the cleaning

What is ATP ?What is ATP ?

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Testing For Allergens : Direct and Indirect Testing For Allergens : Direct and Indirect

•Direct –protein detection –sensitivity

•Direct specific allergen - peanut,hazelnut,almond,sesame,soya,egg,milk caesin,crustacean,wheat gluten,sulphite

•Elisa/lateral flow

•Indirect -ATP

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What is Clean?What is Clean?

• What is acceptable / Fitness for purpose ?

• What is attainable?

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Setting Standards: Why?Setting Standards: Why?

• “Cannot manage what cannot measure”

• Need to know where you are

• Benchmarking

• Scientific approach


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What is Acceptable?What is Acceptable?

• USA <5cfu / cm2

• SFSA Target 1cfu / cm2

Max 3cfu / cm2

• EU / UK Meat legislation <10cfu / cm2

1cfu / cm2 Enterobacteriaceae

• Australia Sat <5cfu / cm2 Unsat <10cfu/cm2


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What is Attainable?What is Attainable?

• UWIC <2.5cfu / cm2 or 250/500 RLUs


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Both are Important and both tell you something about your systems BUT

End Product and Surface Testing End Product and Surface Testing


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Both are Important and both tell you something about your systems BUT

End Product Testing tells you something may HAVE GONE wrong

Surface testing tells you if something may GO wrong in the future

Griffith, 2008

End Product and Surface Testing End Product and Surface Testing


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EU Criteria Regs 2073/2005Sampling of the production and processing

environment can be a useful tool to identify and prevent the presence of pathogenic microorganisms in food.

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Summary Summary

• Definition of terms

• Presence of Residues or Microorganisms on surfaces can pose a health risk

• Important to assess and test surface after cleaning

• Variety of methods –integrated approach

• Benchmark values

• Predictive nature of surface testing


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Summary 2Summary 2

• Assessing cleanliness important in Management

- validation, monitoring and verification

• Variety of test methods

• Integrated Strategy: micro and non-micro

• ATP valuable rapid technique

• Assessing cleaning can provide an early/advance warning of food safety problems


Documents

UWIC How Clean is Clean : Does it Matter ? Prof Chris Griffith Technical Director Von Holy Consulting Emeritus Professor Cardiff School of Health Sciences