ISO 22000: Validation of Food Safety Management System

Validation 

ISO 22000 applies to all enterprises and organizations that directly has impact on the food chain, including feed producers, primary product producers (farms, fisheries, livestock producers), food manufacturers, retailers, restaurateurs and caterers, cleaning / washing / sterilization / disinfection service providers, transport and storage, as well as delivery services. In addition, the standard also applies to enterprises and organizations that are indirectly involved in the food chain, including equipment suppliers, cleaning agent and sterilization and disinfectant suppliers, packaging material suppliers, and suppliers of materials that come into contact with food products.

The food safety management system needs to include the capacity to plan and implement processes to verify the effectiveness of control measures, to validate them and to improve itself.

The concepts of monitoring, verification and validation can be confusing. ISO 22000 defines them as follows.

Validation (food safety) – “obtaining evidence that the control measures managed by the HACCP plan and by the operational PRPs are capable of being effective” – it is an assessment prior to starting operations.

Verification – “confirmation, through the provision of objective evidence, that specified requirements have been fulfilled” – it is an assessment carried out during and after operations.

Monitoring – “conducting a planned sequence of observations or measurements to assess whether control measures are operating as intended” – it is an activity undertaken during operations.

The organization must validate the effectiveness of its operational PRPs and CCPs prior to finalizing the food safety management system, or whenever these control measures are changed.

Validation consists of a combination of tools used to ensure the total food safety management system is working to evaluate food safety data prior to release of the product through either internal or external audits. The validation can be defined as “obtaining evidence that a control measures or combination of control measures managed by the HACCP plan and by the operational PRPs are capable of being effective, if properly implemented is capable of controlling the hazard to specified outcome”.

Validation asks whether the hazard analysis was complete and if the control measures are effective “Are you doing the right thing”. The organization will validate that the selected control measures to verify whether they are capable of controlling the food safety hazards and control measures are effective and capable of ensuring control of the food safety hazards. If this cannot be confirmed, modify and reassess.

Prior to the implementation of your organization’s food safety management system, each operational PRP and CCP must be validated to determine if it is capable of achieving the intended control of the identified hazards. The control measures or combinations of control measures must demonstrate that they are capable of ensuring that the end products of the processes meet the defined acceptable levels.

The organization has a responsibility to make certain that their food safety management system is designed to produce the desired controls, is operated as designed, and is updated as new information is provided. This can become a complicated process.

The food safety management system should be developed using sound scientific principles. The necessary information for the system design can usually be obtained from colleges and universities, government agencies or research branches, trade or industry associations, consultants, or other parties that have expertise in the food process and product.

Once you have designed your control measures on paper, they must be validated. The validation process provides assurance that the control measure or the combination of control measures will deliver end products that are safe (i.e. within the acceptable levels required for each identified hazard).

Validation usually includes activities such as:

1. Reference to validations carried out by others or historical knowledge;
2. Experimental trials to mimic process conditions;
3. Collection of biological, chemical and physical hazard data during normal operating conditions;
4. Statistically designed surveys;
5. Generally accepted industrial practices;
6. Mathematical modeling;

If you are relying upon validations carried out by others, then you should ensure that the conditions of your application are consistent with those identified in the referenced validations.

Scaling up laboratory based experimental trials in a pilot plant may be required to ensure that the trials properly reflect actual processing variables and conditions. Intermediate and/or finished product sampling and testing based on the use of statistical sampling plans and validated testing methodology may be used.

Validations may be conducted by external parties. Microbiological or analytical testing can be used effectively to validate that a process is in control and that acceptable product is being produced.

If additional control measures, new technology or equipment, changes in the control measures, identification of new or emerging hazards or their frequency of occurrence, or unexplained failures of the system occur, re-validation of the system may be necessary.

Reassessment or Revalidation

The ISO 22000 food safety system literature uses the term “revalidation” or “reassessment” in regard to operational oversight. Most of the time, reassessment or revalidation refers to annual review activities that must be conducted to ensure that the ISO 22000 food safety system is operating as intended. In reality, a complete revalidation similar to the design qualification, installation qualification and operational qualification used in thermal processing protocols is rarely done. A complete validation or revalidation study needs to be conducted only if there are significant changes in processes, ingredients, products or equipment that can affect the food safety of the product.

If a complete revalidation is not needed, the plant should conduct either an annual or a continual reassessment of its ISO 22000 food safety system. The objective of reassessment is to determine whether the ISO 22000 food safety system (basically the HACCP plan and the PRPs) is operating as intended.

The reassessment should help answer the following question: Is the ISO 22000 food safety system (HACCP plan and PRPs) adequate to control the identified food safety hazards? The reassessment should lead to identification of activities to improve the ISO 22000 food safety system. It can be used as input for other verification activities, including the internal audit and management review.

Validation of Metal Detectors (an example)

Most metal detectors can be described as a tunnel with a conveyor. Validation data should ensure that the equipment can detect metal of the appropriate size at different locations on the belt, and at different locations in or around the package. For example, if a 50-lb. sack of flour is to be tested, the system could be validated by testing the standards at the leading edge, the tailing edge, on top of and under the bag.

This needs to be done for each product type. The validation protocol might even require that the standards be inserted into the bag at different locations. Multiple tests—a minimum of 10—should be done at each location. The people doing the validation study must also confirm that the settings remain the same throughout the test. The result should be the determination of where to place the test wands during calibration checks in the course of normal production. The location needs to be the spot where the magnetometer receives the weakest signal. Isn’t that a lot of work? Yes, but a rigorous test protocol such as this will provide confidence that the system works properly.

Validation of Control Measures to Inactivate Salmonella

When a lethality step is needed to inactivate Salmonella in a low-moisture product or ingredient, the processing parameters used should be adequate to inactivate the level of the organism likely to be present. According to the National Advisory Committee on Microbiological Criteria for Foods (NACMCF), validation encompasses collecting and evaluating scientific data and technical information to demonstrate that the control measures and associated critical limits at the lethality step, when followed, will result in a safe product (NACMCF, 1998). In addition, it is necessary to demonstrate that the chosen control measure and critical limits can be applied in production at a critical control point. Validation of lethality steps for low-moisture foods involves determining an appropriate log reduction for Salmonella, determining the critical limits in the process required to achieve the reduction, and confirming the process equipment consistently delivers the critical limit parameters in the operation (NACMCF, 1998; Scott et al., 2006).

In general, NACMCF’s definition for pasteurization (NACMCF, 2006) can be used to guide the determination of an appropriate level of log reduction. With respect to a low-moisture product, NACMCF’s definition translates into applying any process, treatment, or combination thereof, to reduce the most resistant Salmonella serotype “to a level that is not likely to present a public health risk under normal conditions of distribution and storage.” NACMCF also indicated that a control measure aimed at inactivating the target pathogen does not protect the consumer if the product is subsequently recontaminated during manufacturing. The effective approach to prevent recontamination is through good hygiene practices verified by environmental monitoring to ensure that recontamination is not likely to occur.

The level of reduction required will depend on the potential levels of Salmonella, if present, in the raw ingredients. Efforts have been made to set an appropriate level of log reduction for a specific low-moisture product based on a risk assessment. For example, a risk assessment (Danyluk et al., 2006) conducted to assess the risk of salmonellosis from almond consumption was used to determine that a 4-log reduction of Salmonella in raw almonds is adequate to ensure safety of the finished product (AMS, 2007). In some instances, historical knowledge is used as the basis for validation (Scott, 2005).

For example, pasteurization at 72 °C for 15 sec is considered adequate to inactivate expected levels of vegetative pathogens of concern in raw milk. These parameters may be used as the critical limits or the basis to establish other process parameters as critical limits at the lethality step to inactivate Salmonella in the fluid milk ingredient for a dried milk product; preventing recontamination after pasteurization during drying and subsequent handling would be essential to protect the finished dried product from recontamination. Both industry guidelines (Froning et al., 2002) and FSIS regulations in 9 CFR 590.575 (CFR, 2008a) set parameters for the pasteurization of dried egg white, which include heating the product in a closed container to at least 130 °F (54.4 °C) for 7 days or longer until Salmonella is no longer detected (As a practical matter, the egg industry routinely uses a more severe heat treatment in order to eliminate the avian influenza virus as well as Salmonella). However, after pasteurization during drying and subsequent handling would be essential to protect the finished dried product from recontamination.

Both thermal and non-thermal control measures can be used for Salmonella inactivation to achieve the target log reduction. Various processing steps (e.g., cooking, frying, roasting, baking, heat extruding, fumigation) may be used to inactivate Salmonella in a low-moisture product. Thermal processing is the most commonly used control measure to inactivate Salmonella.

For example, the Almond Board of California’s Technical Expert Review Panel (ABC TERP) determined that oil roasting at or above 260 °F (126.7 °C) for 2 min will result in a 5-log reduction of Salmonella on the surface of whole almonds (ABC, 2007). The ABC TERP also provided minimum time and temperature combinations required for blanching processes to deliver a 4 or 5-log reduction of Salmonella on almonds (ABC, 2007). These parameters were determined based on heat resistance data for Salmonella Enteritidis PT 30 as the target organism.

It is useful to review available scientific data for the processing method of interest, including high temperature short time or low temperature long time when desirable for maintaining product quality. In order to assure appropriate validation, it is also necessary to evaluate scientific and processing equipment data and information specific to the processing technology under consideration. A process authority should be consulted where necessary.

For example, the ABC TERP, which consists of experienced microbiologists and processing experts, evaluates the adequacy of various treatments to inactivate Salmonella in raw almonds and develops guidelines for validating individual processes, including propylene oxide (PPO) treatment for raw almond kernels, PPO treatment for in-shell almonds, blanching, oil roasting, dry roasting and other processes that may be proprietary (ABC, 2007).

Validation testing can be carried out using Salmonella (appropriate strains), using a surrogate organism that has been validated for the product and process under consideration, or using a non-microbial method such as an enzyme that has been validated for use in such applications. When the time and temperature profiles of a process can be mimicked in the laboratory (e.g., oil roasting); a challenge study with appropriate Salmonella strains can be conducted in the laboratory to validate the process (Larkin, 2008). This approach has been used to validate a dry-air roasting process for peanuts, where a lab-scale roaster was used to mimic the actual processing times and temperatures and the process was found adequate to deliver a 4-log reduction of several Salmonella strains (Tuncan, 2008).

Reference:

http://graphics8.nytimes.com/packages/pdf/business/20090515_moss_ingredients/SalmonellaControlGuidance.pdf

http://fskntraining.org/sites/default/files/coca-colaFS09/ISO_08_English.pdf

http://www2.shimadzu.com/applications/lcms/Shimadzu_TechReport_Vol13_LCMS.pdf

http://www.foodsafetymagazine.com/magazine-archive1/augustseptember-2014/a-new-paradigm-for-validation-verification-and-monitoring/

http://www.fsis.usda.gov/OPPDE/rdad/FSISDirectives/5100.2/Meat_and_Poultry_Hazards_Controls_Guide_10042005.pdf