Utilization of Microbial Data to Improve Food Safety Systems

Transcription

1 Beef Industry Guidance Document Utilization of Microbial Data to Improve Food Safety Systems Prepared by: Dr. Lynn Delmore In conjunction with: North American Meat Association A contractor to the Beef Checkoff May

2 Utilization of Microbial Data to Improve Food Safety Systems The following guidelines have been developed to assist operations in utilizing their microbiological data to ultimately improve food safety. Microbiological data supports many facets of food businesses and affects a multitude of decisions that companies make regarding products, processes, equipment, facilities and ultimately their food safety systems. Specifically, microbiological data can be used as an integral part of an environmental testing program, monitoring of product specifications, as an indicator of process control and to support the HACCP system. Testing Programs Companies should have basic sampling and testing programs outlined for all product types, whether the testing is used to ensure that customer specifications are met, or to support internal product specifications for food safety or quality. These programs should outline the frequency of testing, targets, action levels and corrective actions to be taken when results exceed targets or action levels. As with all things, it is critical to have well trained staff collecting samples following aseptic procedures. Proper use of sampling technique, sample preparation and sample shipment to the laboratory should be verified routinely. Poor sample collection can negatively impact results and result in inaccurate information. Programs should define when, and if, product will be held in inventory pending test results and how the product will be released or how product disposition will be determined when counts exceed standards. You must know why you are testing and what you will do when you receive the results. Every operation must plan for positive results. If you don t know what you will do with a positive then stop testing until you have a plan. Recalls can be devastating to a company; they are expensive and can damage reputations. All recalls result in the loss of consumer confidence of all meat products. These points underscore the importance of planning in regards to microbiological sampling. Plants must use their microbiological data to determine more than just a pass/fail for one particular lot of product, but rather to determine areas for opportunity for improvement. The old adage you can t control what you don t measure holds true in any food processing environment. Trending data over time improves a plants ability to investigate reoccurring system failures, which allows plants to effectively direct plant resources and improve processes. A well-executed process control plan will aid companies in meeting customer expectations and product specifications while creating a framework from which continuous improvement can be achieved. Quick Tip: You must preplan what to do with all microbiological test results before you begin testing. This is especially important when you are testing for microbial pathogens. Environmental Testing/Sanitation Verification 2

3 Baseline Monitoring It is important that plants understand the microbial population of their processing environment, equipment, incoming raw materials, and finished products. Processing Environment/Equipment Plants should establish baseline microbiological counts for the facility to determine if they are maintaining a sanitary environment. Traditional swabs for Total Plate Count (TPC) or Aerobic Plate Count (APC) (these terms are often used interchangeably) are used in most instances, however, ATP bioluminescence technologies may be used to aid in establishing and controlling the sanitary conditions in a facility. ATP data provides real time feedback to the sanitation personnel and immediately corrects any deficiencies found, while traditional swabs typically take 48 hours to get results. Traditional microbiological swabs used in conjunction with ATP swabs can be very successful in establishing, controlling and continuously improving the processing environment and equipment counts. Baseline monitoring for Listeria in Ready to Eat (RTE) environments requires an aggressive approach that in some plants may include seasonality of process and raw material condition. Frequencies of sampling may be heightened to determine growth patterns, especially on conveyors systems or high traffic areas where the potential for cross contamination and over growth is a factor. Based on the baseline data, each plant should develop individual targets for their operation. Baseline data will differ for each operation, and thus, target levels will differ. Raw Materials Baseline monitoring of raw materials typically include analyses for Total Plate Counts (TPC) or Aerobic Plate Count (APC), Total Coliform Counts (TCC) and possibly pathogens of concern such as E. coli O157:H7, Salmonella or Listeria. Once a plant understands the baseline microbiological profile of its raw materials, it can then set reasonable raw material specifications. Finished Product Similarly, it is necessary for operations to understand the baseline microbiological quality of their finished products. From this information, informed decisions can be made as to the true risks associated with the final product and action plans can be developed to minimize those risks. Finished product specification can be developed based on the microbiological baseline data for finished products. Quick Tip: To establish standards for baseline monitoring, plants should conduct their own tests and set standards based on those results. Plant Sanitation Verification In most cases, sanitation verification testing should include analyses for APC. These data should be trended over time; using statistical process control plants may be able to identify sanitation trends prior to them becoming problematic. These result will serve to verify the efficacy of a plant s Sanitation Standard Operating Procedures (SSOP s). In a RTE environment Listeria spp. testing is necessary in addition to sampling for APC. Listeria Control 3

4 The industry typically monitors for Listeria spp. as an indicator of potential Listeria monocytogenes contamination. Listeria is easily killed by thermal treatment, thus when found in RTE products it is most often considered a post-processing environmental contaminate. Therefore, control of Listeria monocytogenes in RTE foods focuses on determining the likelihood that the microorganism exists in the post-processing environment. Areas included in the postprocessing environment are any transitions between raw production and thermal processing areas, finished product staging areas/coolers and the packaging rooms. Programs should be in place to monitor Listeria spp. and apply corrective actions when necessary in all Ready-to-Eat processing environments. The program should include site selection, a sampling plan (including frequency), and details on methods and laboratory accreditations. The importance of site selection cannot be overlooked, if plants are not sampling the most risky locations they will get a false sense of security that the Listeria Control Program is working. Equally important, the program must include corrective actions, including follow up samples to positive results. The Listeria control regulation (9CFR340) requires food contact surface sampling for products produced under Alternative 2 or 3. The FSIS Compliance Guideline: "Controlling Listeria monocytogenes (Lm) in Post-lethality Exposed Ready-to-Eat (RTE) Meat and Poultry Products, 2012 provides base level testing recommendation for all three alternatives, however these are the minimum number of tests that should be taken. All operations will need to conduct additional analyses from time to time. Quick Tip: Question if the results make sense, all negative results may, in fact, indicate that your sample site selection needs to be reviewed. Developing and Maintaining Sample Sites and Sample Frequency Every plant is unique in its facility layout, equipment sanitary design and configuration, and perhaps most importantly, the product and traffic flow of the plant. A company must consider all of these factors when determining the appropriate sampling sites and frequency of sampling; they all contribute to the potential spread of Listeria from raw to RTE areas of the plant, thus resulting in the possible recontamination of RTE products. Plants should refer to Industry resources (i.e. Sanitary Equipment Design (American Meat Institute); Industry Guidelines to Prevent Contamination from Listeria monocytogenes (National Pork Board and American Meat Science Association)) and use them to establish a sampling approach based on their particular operation and the highest risk areas. The Zone method of environmental monitoring is commonly used in the RTE meat and poultry industry. The plant is divided into zones based on the level of risk in each area. Zone 1 represent the highest level of risk and is designated as food contact surfaces (FCS). Zone 2 sampling sites are Near Food Contact those areas directly adjacent to the FCS. Zone 3 is Non-Food Contact, and includes other sites within the processing area such as walls, floors, drains etc. Distant locations not in the processing area are sampled as Zone 4 (commonly welfare facilities). Plants first focus their sampling and testing efforts on Zone 1 sites until those areas are under control. Then, plants can move the focus of sampling and testing to the other Zones. When any samples are found positive for Listeria spp., the frequency of samples taken will increase until such time that the data show that all Zones of the processing environment are back under control. Although Listeria spp. is not considered an adulterant in RTE products, when positives for Listeria spp. are identified on Food Contact 4

5 Surfaces it is advisable that corrective actions be taken that would mirror a positive finding for Listeria monocytogenes (it is advised that product sampling always be for Listeria monocytogenes). In some instances, Listeria monitoring will help companies identify areas for improvement in sanitary equipment design. By considering the principles of Sanitary Equipment Design, plants can improve the cleanability of their operations and ultimately decrease the risk of Listeria contamination in their products. Verification and ongoing monitoring programs require that the sites established during the baseline study are routinely monitored for both unusual activity such as spikes or positives; but more importantly result plateaus where the results remain constant. These are at times warning signs that the plant and the program may have become too reliant on data that provides the same answer over and over. In the case of Listeria control, all negatives may be, and have at times been, THE only warning sign that the verification has become too complacent just before products test positive. The maintenance and effectiveness of all programs relies on the diligence of the data review. Quick Tip: Be creative in determining sampling sites for Listeria spp. testing, try to sample the hardest to clean spots. Product Specifications Raw Material Specifications It is essential to monitor raw materials on an on-going basis to understand the microbial contribution of all raw materials. Ultimately, the microbiological quality of the raw materials will significantly impact the microbial quality of finished products and/or shelf life. Microbiological monitoring of raw materials can be two-fold. First micro data can be used to determine basic acceptance or rejection of raw materials on a per lot basis. Secondly, micro testing should be used to trend the microbiological quality over time. Acceptance or Rejection Micro testing is often used as a tool for acceptance or rejection. As E. coli O157:H7 and 6 other non-o157:h7 Shiga Toxin Producing E. coli (STECs) are considered adulterants in non-intact Beef (including ground, blade tenderized, and needle injected beef products) many manufactures require testing of raw materials intended for these products as a pre-purchase requirement. Most trimmings are only tested for the presence of E. coli O157:H7 as it is believed that practices and interventions to minimize the presence of E. coli O157:H7 are equally effective on the other STECs. Trimmings used as raw materials are often sampled by suppliers and samples analyzed for presence or absence of microbial pathogens, most commonly for E. coli O157:H7, and Certificates of Analysis (COA s) are issued for samples found negative. Most commonly, these COA s must be presented by the supplier prior to or upon receiving of the raw material by the processor. Microbiological Trending Microbiological monitoring of raw materials over time should include analysis for APC, possibly TCC or ECC (E. coli Count) and Salmonella spp. This analysis allows companies to profile their suppliers and make informed purchasing decisions based on the microbiological quality of the raw materials. 5

6 Quick Tip: One of the best ways to improve the quality and shelf-life of your finished product is to improve the quality and microbiological quality of your raw material. Finished Product Specifications Finished product testing requirements will vary depending on the type of product and customer specifications. Microbiological testing of products can be used to monitor both the food safety and quality attributes of your products, which may include testing for pathogens and non-pathogenic organisms. These data can verify that a plant s food safety systems are working as intended, but may also be used to determine if products are meeting quality targets. Quality measurements may be used to control shelf-life and meet customer requirements. Raw, Finished Products Finished product testing for raw product may include analysis for APC, TCC, ECC and possibly pathogens such as Salmonella spp., E. coli O157:H7 and/or other non- O157:H7 STECs. The use of pathogen testing for finished product that are raw tend to be customer specific. Always remember when testing for pathogens to hold all product pending results. RTE, Finished Products Likewise, RTE finished product testing programs may include analysis for APC, TCC, ECC. Analysis for pathogens can be useful at some frequency to verify the food safety system is functioning as intended. Pathogen testing may include Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., and E. coli O157:H7 and/or other non- O157:H7 STECs. As with raw finished products, the use of pathogen testing for finished product tends to be customer specific. Again, always remember when testing for pathogens to hold all product pending results. Process Control Tools A true process control plan will help a company not only meet customer and product specifications more efficiently, but will allow for continuous improvement. To achieve this many plants implement Statistical Process Control (SPC) programs. This can be accomplished utilizing very simple technologies (hand drawn graphs), or rather sophisticated software packages. It is likely that a company s current database has some SPC capabilities. For instance, Microsoft Excel has many basic statistical analysis tools available and for those wanting more advanced statistical capabilities, a SPC add-on is available for Excel. The easiest and most common statistical analyses are X-bar (average) and R (range). In using SPC, a facility will set clear operating targets for both the average and range, and identify action levels for various processing parameters. These operating limits will be set based on the acceptable variance from the target (3 standard deviations are typically considered acceptable). Should the process begin to trend away from the target, the management can immediately apply a process adjustment to bring the process back under control, hopefully prior to exceeding any process limits. This reduces the amount of product that would otherwise need corrective action due to exceeding the process limits by identifying and fixing the issue before the product is out of specification. If the deviation of a processing parameter occurs, this may indicate that the process has encountered something unusual, thus necessitating further investigation. Identification of any processing trends can be used over time to identify areas of opportunity for improvement. Thus, data collected not only serves to immediately determine if the process is functioning as intended, but also to trend the process over time, allowing for continuous 6

7 process improvement. SPC should be applied to finished products and the environmental monitoring program; it can also be useful in raw material monitoring. Quick Tip: Simple averages and range can help identify if the raw material supply and/or finished product is meeting specifications and allow for continuous improvement. HACCP System When developing food safety systems, microbiological data is almost always necessary to validate a HACCP plan. Micro data is used to show that the CCP, when implemented as intended, will control the specified biological hazard. On an on-going basis, micro data can be used to verify that the HACCP plan is working as intended. However, micro results do not typically make good CCP s, as they cannot be monitored in real time. Thus, microbiological data should not generally be used for CCP monitoring. In some cases, testing for E. coli O157:H7 is used as a CCP for beef trim, and all product must be held pending microbiological results. Microbiological monitoring is most useful in HACCP systems to validate CCP s and verify CCP and HACCP system efficacy. Quick Tip: Micro testing is rarely used as a CCP for HACCP, more often microbiological testing is used in validation and verification of CCP s and of the HACCP system as a whole. Validation All food safety systems must be validated. For HACCP, in most cases, validation is the process of demonstrating that the HACCP plan, when conducted as planned, will control the microbiological risks identified for a specific product and process and will meet regulatory requirements. For companies processing raw products, this often includes showing that a facility s temperature controls and microbial interventions are controlling the organism(s) of concern for their product category. In cooked operations, microbial validation is most likely demonstrating that thermal processing and proper cooling, when implemented following the HACCP plan, will control the organism(s) of concern as intended. For Ready to Eat (RTE) operations, microbial validation will document that Listeria control ingredients and/or processes will control Listeria monocytogenes in the finished products. Validation must be product/process specific. Verification Verification is the process of showing that the food safety systems are controlling the microbiological risks identified for a specific product and process on an on-going basis. Much of a facility s product testing and environmental testing results are utilized as part of verification. For raw operations, microbiological verification is achieved by testing for pathogens of concern at some frequency. For RTE operations, this would include verifying that the Listeria Control Program is controlling Listeria spp. in the post-processing environment and for Listeria monocytogenes the finished product at some frequency. 7

8 Data Management With all of this microbiological analyses comes the challenge of managing the data. A well thought out, properly designed data management system begins by collecting the right data. Data should be collected with purpose. Collecting data for the sake of collecting data, without a specific intent or goal, is a waste of time and money. So, plants should ask themselves, What do I want to learn? What do I want it to show me?, keeping in mind that data should accomplish specific goals. All data must be managed in a manner that is organized and allows proper review and investigation. Companies invest significant resources into microbiological testing programs, thus it is important to get the most from the results. By incorporating microbial data from the many testing programs in the food safety decision making process, food manufactures can significantly improve their food safety systems. Quick Tip: All data should be collected with a specific intent or goal. 8