Cleaning in a food environment

1. Cleaning in a food environment

2. Cleaning in a food environment • Why Clean? • A little science • The role of water • surfactants • Choice of cleaning products • Terminal disinfectants • Miscellaneous issues • Procedures • Staff Training • Do’s and Don’ts • Conclusion

3. Why Clean? • Remove previous production • Avoid cross contamination • Equipment maintenance • Improve working environment • Customer demand • Avoid microbial contamination • Stay in business

4. Properties of water High melting & boiling temperatures High surface tension High energy content Expands on freezing Effective solvent These properties depend on the structure of the water molecule A little science

5. Properties of water • Water molecule • One oxygen atom • eight protons & electrons • Two hydrogen atoms • one proton and electron • Electrons tend to be attracted to oxygen • Slight charge imbalance • Polar molecule

6. Properties of water • Water molecules are attracted to each other • Hydrogen bonding • Leads to a 3D Network which gives water some of its unique properties

7. Surface tension • Forces between water molecules; • Evenly balanced in centre • Uneven at surface • Resulting tension leads to problems with wetting

8. Detergents • Detergent molecules • Hydrophyllic (water loving) head • Hydrophobic (water hating) tail

9. Surfactants • Detergent molecule will form a layer on surface of an oil droplet • hydrophobic tail in the oil • hydrophyllic head in the water

10. Surfactants • Surplus detergent molecules cluster together in micelles with tails inward and heads outward

11. Surfactants • These surfactant properties of detergents lead to • lowering of surface tension leading to improved wetting • loosening of dirt on a surface • holds oil in suspension • prevents redeposition of dirt

12. Types of surfactant • Anionic • Common general purpose cleaners • Often alkaline in solution • Non-ionic • milder cleaning action • rarely used on their own • Cationic and amphoteric • not generally used as cleaning agents • can act as biocides

13. Choosing cleaning products • Cleaning regime • Type of clean (open plant? CIP?) • Standard of cleaning required • Types of soil • Typical microbial contamination • Risks • of contaminating the food • to people (COSHH) • to equipment • Resources: labour, time, equipment • Environmental: effect on effluent

14. Basic Cleaning Procedure • Preparation • Removal of gross dirt • Cleaning • Main cleaning stage • Rinsing • Disinfection • Rinsing • May be omitted if sanitiser designed to be left on

15. Types of clean • Dry clean • removal of dirt by physical means • Hand clean • use neutral or mildly alkaline cleaners plus physical energy • ensure cleanliness of cleaning equipment • Soak clean • Enhance contact time for bad soil • Detergents often very alkaline • special formulations sometimes needed • e.g. with aluminium

16. Types of clean • Foam or gel clean • Enhances contact time • Alkaline detergents usually used • Chlorinated caustic products effective on proteins • Still needs physical energy to remove dirt • Care needs to be taken with spray washdown systems

17. Types of clean • Automated washing machines • used for trays, racks, bins, utensils etc. • use alkaline detergents for plastics and steel • neutral or specially formulated detergents for aluminium • Cleaning in place • Often uses very aggressive chemicals • Usually caustic/sequestrating • Acid formulations effective on some soils

18. Material issues • Plastics may be susceptible to stress corrosion cracking with neutral/alkaline detergents • Soft metals such as aluminium or brass may be attacked by detergents • Should use special formulations

19. Terminal disinfectants • Should specify to deal with likely micro-organisms • Often inactivated by detergents • thorough rinsing essential before disinfection • Quaternary ammonium compounds widely used • they are relatively low cost • few problems with taint • not effective against all micro-organisms esp. gram negatives such as listeria

20. Terminal disinfectants • Amphoteric surfactants • More expensive • effective against gram negative bacteria • Some suppliers are now offering dual biocides • To rinse or not to rinse? • UK law permits you to leave terminal disinfectants on your equipment without rinsing • EC regulations require a final rinse to remove terminal disinfectants • Which is preferable?

21. Procedures & Documentation • Cleaning Schedules • What? When? How? • Documentation • Keep proper records • Ensure records are accurate (due diligence) • Hygiene testing • Rapid or traditional?

22. Documentation • Detail: Through the day, daily, weekly, monthly, quarterly, annual • Involve hygiene staff in detail of production of routines • Agree correct names of machines • Use checklists to record who cleaned what and when

23. Hygiene Testing • Rapid or traditional? • Rapid • results in a few minutes • production tool • clearance after cleaning • Part of HACCP • Traditional • Part of QC • Established and known • Identifies organisms

24. Training • Cleaning is start of process not end • Start with a clean plant • Do not relegate inept staff to cleaning team • Be aware of new chemicals/processes • Rotate staff round whole factory • Feedback good results don’t just complain about bad ones! • Ensure trainers are properly trained. • Accreditation via outside approved organisations

25. What can go wrong? • Untrained people • Inappropriate chemicals and equipment • rotate terminal disinfectants • Water problems • Poor safety equipment • Poor cleaning/storage of equipment • Pressure on production

26. What can go right? • Build in cleaning at design stage • Proper engineering of equipment • Clean correctly and • Stay in business • build reputation • open new markets

27. Miscellaneous issues • Choice of supplier • Select supplier with good backup • Work with supplier on technical issues • Testing for cleanliness • Traditional microbiological testing is reliable but time consuming • Rapid methods give quick results, and give confidence for restart • Based on detecting biological materials

28. Concluding comments • Effective cleaning depends on • An understanding of materials and equipment • Effective relationships with suppliers • Effective systems which operate in practice • Above all it should be part of a culture of hygiene within the company