Microbiological criteria - an introduction

1. Microbiological criteria- an introduction Jens Kirk Andersen The National Food Institute Technical University of Denmark

2. No of human cases in Denmark:

3. Sampling • Testing • Made decision on the result

4. 4 pages that changed the world: 1997:

6. Microbiological Criterion (Codex, 1997): • A criterion defining the acceptability of a product or a food lot, based on the absence or presence, or number of microorganisms including parasites, and/or quantity of their toxins/metabolites, per unit(s) of mass, volume, area or lot

7. Microbiologicalcriteriumconsists of: • The microorganism • Analytical method • Sampling plan • Acceptable limit/limits • The food for which the criterion applies • The place in the food chain where it applies • Action on failure to meet the criterion Codex, 1997

8. Codex, 1997: • Food safety is assured by GHP and HACCP • Microbiological criteria should be based on science • Developed in a transparent fashion • Meet the requirements for fair trade • Setting of Microbiological Criteria is a Risk Management task

9. Risk Analysis Risk Assessment Risk Management Scientific Independent Unemotional “Ivory tower” Pragmatic Possible Political Policy Take decision

10. Application of MC (Codex, 1997): • Where no other more effective tools are available • When they are expected to improve the degree of protection offered to the consumer

11. Sampling uncertainty “Even if you search you shall not always find”

12. Possibility of accepting a contaminated lot:

13. No of samples, to document ”absence” ? Def.: ”prescencebelow 1% at 95% probability” Bacthsize No of sample units 1- 60 all 151 - 175 135 276 - 360 190 651 - 1000 250 2001 - 3000 290

14. Guarantee - Zero tolerance? • Not possible • We cannot test everything • Not realistic • We need to eat • Not necessary • Pathogens in low levels may be acceptable

15. The purpose of an MC is to reduce the risk of the consumer 3 steps to heaven: Step 1:Hygiene-based MC - Hygiene parameter, E. coli, TVC etc. Step 2: Hazard-based MC - Pathogenic microorganisms Step 3: Risk-based MC - Directly (mathematically) related to consumer risk – outcome

16. EU microbiological criteria • Proces Hygiene criteria • Hygiene parameters • 3-class plans • Reaction: Improvement of hygiene + review of HACCP

17. Example:Process hygiene criteria (EU legislation)

18. EU microbiological criteria • Food safety criteria • Pathogenic microorganisms • 2-class plans • Dramatic reaction when non-complience: • Withdrawal • Recall

19. n c m M Class Plan Listeria monocytogenes 5 0 100 cfu/g a NA 2b Microbiological criteria for RTE foods in which growth of L. monocytogenes will not occur [a This criterion is based on the use of the ISO 11290-2 method. A 25 g sample unit is taken, diluted in 225 ml and homogenized. Duplicate 1 ml portions of this 1:10 dilution of a 25 g sample unit are divided equally onto three standard agar plates (90 mm diameter) or one big agar plate (140 mm diameter) and plated. Thus, two replicate analytical portions of 0.1 g are plated for each original 25-g sample.] Other methods that provide equivalent sensitivity, reproducibility, and reliability can be employed if they have been appropriately validated. National governments should provide guidance on how samples should be collected and handled, and the degree to which compositing of samples can be employed. [bThis sampling plan would provide 95% confidence that a lot of food containing an average concentration of 93.3 cfu/g and an analytical standard deviation of 0.25 log cfu/g would be detected and rejected based on any of the five samples being positive for L. monocytogenes.]

20. Towards a risk-based approach: • Work has been going on for several years • The risk-based angle is being used increasingly in Codex Food Hygiene Committee

21. There must be a link between the level of hazard in a food, and the risk for the consumer • Therefore it should be possible to translate the level of protection to a microbiological criterion

22. ALOP, the Appropriate Level of Protection: The level of protection deemed appropriate by the Member establishing a sanitary or phytosanitary measure to protect human, animal or plant life or health within its territory (Definition by WTO 1995)

23. FSO, Food Safety Objective: The maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the appropriate level of protection (ALOP) (Definition: CAC 2007)

24. PO, Performance Objective: The maximum frequency and/or concentration of a hazard in a food at a specified step in the food chain before the time of consumption that provides, or contributes to, an FSO or ALOP as appropriate (Definition: CAC 2007)

25. The missing link: • The transition from Performance Objective to Microbiological Criterion? • Two examples on how to do this will be presented at this WG!

26. ALOP Human FSO Meal/RTE PO Food Chain PO The construction of these parameters form a “cascade” with the ALOP at the top, describing what we are trying to achieve. MC MC

27. Alternative approach The principle is simple: Take a sample Do the testing Perform a risk assessment on the result Compare the risk to the average (baseline) risk Acceptability of the food is conditioned on the relative risk An example on this approach is also being presented at this meeting

28. Thank you for your attention