Environmental Monitoring for Listeria in Fresh Produce

Transcription

1 Environmental Monitoring for Listeria in Fresh Produce Margaret D. Hardin, Ph.D. Vice President Technical Services IEH Laboratories & Consulting Group Lake Forest Park, WA June 9, 2015

2 Sampling & Testing

3 Before You Take a Sample Ask yourself: What are your objectives in taking the sample and performing the test? What will the results mean and what will you do with the results?

4 Getting Started Assemble your team; designate a team leader Assemble a cross functional team familiar with your operation to help identify potential areas of risk or concern, including: * Quality manager * Plant Engineer * Microbiologist * Maintenance * Sanitation * Line Supervisor *Operations Manager * Warehousing

5 Getting Started understand your process flow with an emphasis on identifying potential points of product recontamination Blueprints and flow diagrams; walk the plant floor conduct environmental monitoring in nonproduction areas, but you need to understand that you will occasionally find Listeria in those areas

6 Hygienic Zone Assessment Conduct a hygienic zone assessment to determine what is considered the Primary Listeria Control Area areas where post lethality treated product (finished product) is exposed to the environment.the Ready to Eat (RTE) area the high hygiene or high risk area The objective of hygiene zones: is to identify areas of high and low risk to the product within the manufacturing operation to prevent the spread of Listeria into the PLCA where protection of the exposed post lethality product is critical.

7 Hygienic Zone Assessment Conduct a hygiene zone assessment of the entire facility and create a color coded map: Evaluate all production areas, storage, receiving, warehousing and loading docks, employee facilities such as cafeterias, break rooms, locker rooms, washrooms, maintenance areas, offices/conference rooms, etc. Designate the basic GMP areas, transition areas, and non processing areas Pay particular attention to areas within the facility where ingredients, products, or the environment could be a potential source of Listeria and a high potential to recontaminate post lethality treated product Also pay attention to non process areas such as forklift charging stations, refuse/recycling areas, loading docks, staging areas, restrooms/breakrooms and others.

8 Plant Layout Hygienic Zones of Control Main Entrance Offices Hallway Employee Welfare Raw material Receiving/Storage Finished Product Warehouse/ Shipping Packaging Post lethality Lethality Pre lethality Steps (Mixing, Grinding, Sifting) PPCA (Primary Pathogen Control Area) Basic GMP Area Non process areas

9 Plant Layout Hygienic Zones of Control Main Entrance Offices Hallway Employee Welfare Raw material Receiving/Storage Finished Product Warehouse/ Shipping Packaging Mixing steps PSCA (Primary Pathogen Control Area) Non process areas

10 Sample Locations & Sanitary Zoning within a Room/Area 1 st Map out the hygienic zones of control in the facility. 2 nd Select specific sampling sites within each room/area. Use the sanitary zoning concept to aid in site selection and in tracking environmental data (the sanitary zoning concept is different than mapping hygienic zones of control within the facility). In the sanitary zoning concept the plant operations are divided into four zones based on level of risk.

11 Sanitary Zones Zone 1 Product Contact Surfaces (Fillers, hoppers, screens, conveyor belts, work tables, product scales, air blowers, utensils, employee hands) Zone 2 Non-Product (next to) Contact Surfaces (exterior of equipment, framework; refrigeration units, equipment housing) Zone 3 Other Areas within RTE Room (air return covers, phones; hand trucks, forklifts, drains) Zone 4 Areas Outside of RTE Room (Locker rooms, cafeteria, hallways, loading dock, maintenance areas)

12 Sources of Listeria in High Risk RTE Area Transferred from Zone 4 area outside of the High Risk RTE area Homeless, but looking for a harborage location Typically found with a transfer point monitoring positive Growth niches within High Risk RTE area 1. This means they are established, and have found a protective home in equipment or facility. 2. They may exist in a transient home such as rework pans, trash containers or other difficult to clean mobile container / environment.

13 Zone 1 Zone 1 Areas in the plant that are direct product contact surfaces after the lethality or microbial reduction step (e.g. roaster) and before the product is sealed in the primary package If there is no lethality step in the process sites where the product is exposed to plant equipment and environment prior to sealing in the primary packaging Conveyor belts/buckets Utensils Employee hands (if touching product) Slicers/dicers; Product hoppers/bins/bin liners Discharge Chutes; Fillers

14 Zone 1 Sampling

15 Zone 2 Zone 2 Non product contact areas in the plant that are closely adjacent to product contact surfaces Equipment framework Drip shields/housings Control panels/buttons Overhead pipes directly over zone 1 surfaces Computer screens Maintenance tools Drains located directly under equipment Motors located adjacent to lines

16 Zone 2 Sampling

17 Zone 3 Zone 3 Non product contact surfaces that are in open postlethality product processing areas, but no closely adjacent to zone 1 surfaces Zone 3 surfaces have the possibility of leading to product recontamination > Floors, walls, ceilings > Trash containers > Hoses > Pallets > Drains > Foot baths/mats > Condensate drip pans > Brooms/mops > Trolleys, forklifts, walk alongs, carts > Fans > Toolboxes

18 Zone 3 Sampling

19 Zone 4 Zone 4 Areas that are more remote from postlethality product processing areas Zone 4 areas if not maintained in good hygienic condition can lead to cross contamination of zone 1 3 areas Hallways; Loading docks Bathrooms; Locker rooms Employee cafeteria/break rooms Coolers/freezers Maintenance shop Office areas

20 Zone 4

21 Testing Methods There are a myriad of sampling and testing methods that can be employed for your PEM program Recommended sampling methods include: Surface sampling using sponges/swabs Product residue scrapings/fines/dust samples Water/rinse samples Air samples Generally, a comprehensive, aggressive environmental monitoring program will use a combination of these sampling methods

22 Establish A Baseline Once potential areas for sampling are identified conduct preliminary intensive investigational sampling to find Listeria if present. Samples are collected at a much higher frequency than is done for the ongoing environmental monitoring program. Zone 1 sites may be tested pre operationally, after cleaning and before sanitizing (prior to start up of the production line) as a measure of cleaning effectiveness.

23 Data Interpretation & Corrective Actions Your facility should have a pre determined action plan that would be implemented in the event of a Listeria positive result The action plan should be specific for each of the four zones and include Type of immediate corrective actions to be taken by zone Actions to be taken to verify Listeria has been eliminated from the area in question A root cause analysis to find the source of the contamination so that it can be prevented in the future

24 Corrective Actions Depending upon the location and circumstances (for example, single result vs. multiple sequential results) the Food Safety Team and Plant Management shall decide what corrective actions will be taken following a positive result. The response team should conduct an in depth investigation looking at areas and considering issues such as:

25 1. Review equipment for harborage areas, such as hollow rollers, rough welds, cracked or damaged surfaces. 2. Inspect the area for potential harborage points. 3. Audit (observe) the Sanitation process to ensure adequacy. 4. Perform an extensive disassembly of equipment (deep dive) for thorough cleaning. 5. Perform extensive cleaning and sanitizing of the room, peripheral areas, and holding coolers. 6. Observe, review and conduct GMP refresher training with all employees, including maintenance, supervisors and managers.

26 7. Audit (observe) and interview employees concerning practices during sanitation, set up, and production. 8. Review sanitation data/records, training, and written SOPs. 9. Review environmental data of the area as well as adjacent areas. 10.Review records for maintenance, downtime (planned and unplanned), and/or construction. 11.Review records for any non standard production activities (e.g. R&D plant trials).

27 12. Review traffic patterns for employees, supplies, equipment, and product. 13. Complete a targeted clean of the area/line. 14. Increase the number of swabs (and sites and zones swabbed). 15. Follow up intensified swabbing (SWAT Team Sampling). Sample during an idle period after sanitation, before production i.e. Saturday when no production is running. Sample larger areas using sponges or gauze. Sample areas not typically sampled during routine sampling (such as air, staging areas, etc.).

28 Data Interpretation & Corrective Actions The response team should look at these factors and all relevant records and documents from last full microbiological cleanup/sanitation prior to the current positive finding. The response team should look at these factors and all relevant records and documents from last full microbiological cleanup/sanitation to the current positive finding Track and trend the results of testing!

29 Preventive Measures Based on the results of the root cause analysis, one or more Preventative Measures may be implemented. These may include, but are not limited to: Revisions to plant SSOPs, MSS Revisions to plant GMPs Retraining of individuals Equipment changes * All preventative measures will be accompanied by a verification plan to assess their efficacy.

30 Data Tracking and Trending To demonstrate that the environment is under control, To identify potential routes of transmission or harborage areas To identify trends which will allow corrective actions to be implemented before a situation develops where there is a loss of control Results must be tracked and trended &reviewed by the Plant Food Safety Team. Recommended methods of trend analysis include, but are not limited to, the following: Each set of samples should be examined for unusual patterns. Sample results can be examined on a daily, weekly and monthly basis (all locations are sampled at least once per month), depending on sampling frequency, for unusual patterns.

31 Results can be sorted by: Total across entire plant; by Area; by Production Line; by equipment; by Zone # and/or surface type (for example, drains) An analysis of results can include: Totals by month; ranking within a sort category (for example hottest drain i.e. exceeds limits most often among all drains) Note any correlations with seasons or episodic events. Document all sample results by preop/operational/post operational or by time and location (site). Document all positive results by site and corrective actions and maintain as part of the testing records.

32 Tracking and Trending Process Control the advantage: Monitor production to detect risk of exceeding control limits Evaluate performance of suppliers Provide warning of potential pathogen event Narrow down problem, i.e. employee vs. process induced 32

33 Indicating positive findings on a map or plant diagram can be very useful. Different colors can be used to show positive and negative results and positives can include a date the sample was taken. This can be extremely valuable in visualizing trends and issues.

34 Data Utilization

35 RAW PRODUCT STAGING LINE Positive swabs identified with routine sampling RAW PRODUCT STAGING LINE DOOR Positive swabs identified with investigative swabbing Concentric circle sampling map Forklift movement

36 Listeria Control Program Too many companies believe their Listeria control program consists primarily in environmental (food contact and non contact) and product testing.this is only a small part of a complete Listeria control program.

37 The bottom line Strategies to Control Pathogens in the Processing Environment 1. Facility Design, Equipment Design & Sanitation Prevention and elimination of growth niches. 2. Management of microbial transfer points people (esp. maintenance and supervisors), equipment, supplies and product traffic control. 3. Implementation of Interventions & Post lethality Technologies (when appropriate) Use of appropriate technologies (e.g. temperature control, antimicrobial additives/dip/sprays, post packaging thermal, and nonthermal treatments, freezing). 4. Sampling and Testing aggressive testing to find Listeria search and destroy approach. 5. Validation, Data Management, Corrective Actions, Verification & Education collect, manage (track/trend), respond, verify, analyze educate!

38 Listeria Control Equation Controlled Traffic Patterns + GMP s Clean, dry, + uncracked + floors Sanitary Design of Equipment/Facilities Effective + Sanitation Procedures = & Controls Listeria Control

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40 Questions? Margaret Hardin