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Use of Microbial Data for Hazard Analysis and Critical Control Point Veri®Cationðfood and Drug Administration Perspective

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Use of Microbial Data for Hazard Analysis and Critical Control Point Veri®Cationðfood and Drug Administration Perspective 810 Journal of Food Protection, Vol. 63, No. 6, 2000, Pages 810±814 Use of Microbial Data for Hazard Analysis and Critical Control Point Veri®cationÐFood and Drug Administration Perspective JOHN E. KVENBERG* AND DARRELL J. SCHWALM Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, HFS-601, 200 C Street S.W., Washington, D.C. 20204, USA MS 99-501: Received 3 September 1999/Accepted 4 February 2000 Downloaded from http://meridian.allenpress.com/jfp/article-pdf/63/6/810/1673832/0362-028x-63_6_810.pdf by guest on 24 September 2021 ABSTRACT This paper examines the role that the microbiologist and microbiological testing play in implementing hazard analysis and critical control point (HACCP) programs. HACCP offers a more comprehensive and science-based alternative for con- trolling food safety hazards compared with traditional sanitation programs based upon good manufacturing practices. Con- trolling hazards under an HACCP program requires a systematic assemblage of reliable data relating to the occurrence, elimination, prevention, and reduction of hazards. These data need to be developed in a transparent environment that will ensure that the best scienti®c methodologies have been employed in developing the needed data. The two mechanisms used in HACCP to assess the adequacy of the database are validation studies and the veri®cation assessments. Microbiological testing is an important mechanism for collecting data used in developing and implementing an HACCP plan. Microbial sample data can help establish standard operating procedures (SOPs) for sanitation, assess the likelihood of the occurrence of hazards, establish critical limits, and assess the validity of the HACCP plan. The use of a performance standard to assess whether microbiological hazards have been reduced to an acceptable level creates an especially important use for microbial analysis. Microbial testing is also useful in implementing an HACCP plan by helping to monitor the effectiveness of sanitation SOPs, the compliance of incoming ingredients with safety criteria, the safety of product being held for corrective action, and the safety of the ®nished product. The veri®cation audits demonstrate that all control measures have been applied as designed in the HACCP plan. Although auditing HACCP records is the primary means of veri®cation, microbial sampling can play an important role as well. The food-manufacturing industry has historically re- processing control measures to determine whether a partic- lied largely upon experience from consumer complaints, ular hazard should be controlled under the ®rm's prereq- product recalls, and reports of illnesses; general scienti®c uisite programs or under the HACCP plan. The following studies; and common sense manufacturing practices to de- is an example cited in the Food and Drug Administration's termine the best methods to use in controlling food safety (FDA's) ``Second Interim Report of Observations and Com- hazards. As more and more manufacturers begin to de- ments'' on the HACCP Pilot Program (3): velop hazaard analysis and critical control point (HACCP) One example encountered during the pilot program in- systems to control food safety hazards, the traditional roles volved a bakery product. The hazard analysis determined of the food microbiologist and microbial sampling are it is reasonably likely that the raw ingredients could contain being re-examined. Speci®cally, ®rms implementing an microbial hazards. During the processing, the product is HACCP program often ®nd that they need: enhanced baked in order to produce a product of a quality that can methods to identify and prioritize hazards to control, and be marketed. Studies conducted of the internal temperatures updated criteria for selecting control measures and select- during baking showed that the baking processing step is ing the operation parameters that will yield the most ef- lethal to any microbial hazard. The studies also showed that fective results. any product that was incompletely baked to such an extent Firms are willing to make these changes because the that the microbial hazards might survive would be too advantages of having a more detailed, science-based and doughy on the inside to undergo a further processing step process-speci®c hazard analysis, as well as scienti®c vali- and would not be suitable for marketing. dation and veri®cation data to document the adequacy of a The microbiologist plays a key role in developing and control system, quickly becomes apparent when adopting conducting such studies, as well as other studies that are in- an HACCP program. strumental to the proper implementation of an HACCP plan. Enhancing food safety controls often necessitates that a manufacturer conduct in-house scienti®c studies of their CHANGING ROLE OF MICROBIOLOGICAL TESTING * Author for correspondence. Tel: 202-205-4180; Fax: 202-205-4121; An important goal of HACCP is to help the food pro- E-mail: [email protected]. cessor build safety into the process through a small number J. Food Prot., Vol. 63, No. 6 USE OF MICROBIAL DATA FOR HACCP VERIFICATION 811 of key or critical control measures that prevent, eliminate, found in its HACCP Pilot Program (2) that most ®rms try or reduce hazards to acceptable levels. An HACCP program to maximize the use of their prerequisite programs to con- shifts the focus of controls toward monitoring in-process trol hazards in order to avoid the strict requirements of the preventive control measures. At the same time there is a controls associated with a critical control point (CCP). FDA diminished focus on monitoring the quality of the ®nished reported in its ®rst Interim Report that ``in some instances, product. This shift in focus also changes the role of micro- the same type of hazards were controlled under the prereq- bial testing. HACCP substantially reduces the need to test uisite programs at one ®rm and under the HACCP plan at the ®nished product for the purpose of assessing the safety another ®rm.'' Either approach was effective as long as the of individual lots of product. prerequisite programs were well documented with standard This shift in focus is important because of the increased operating procedures (SOPs), were fully implemented, and awareness of the shortcomings of microbial testing of ®n- included monitoring records and veri®cation procedures. ished products. Reliance on end-product testing is particu- These veri®cation procedures typically included microbial larly inef®cient and ineffective when a large sample size testing. One ®rm, for example, utilized environmental sam- Downloaded from http://meridian.allenpress.com/jfp/article-pdf/63/6/810/1673832/0362-028x-63_6_810.pdf by guest on 24 September 2021 and high frequency of sampling is needed to provide sta- pling extensively to monitor cleaning and sanitizing of tistically reliable data. The reliability of ®nished product food-contact surfaces and potential sources of environmen- test data is especially poor when trying to detect a pathogen tal contamination such as ¯oor drains. The sampling plan that occurs in low numbers, occurs sporadically, and orig- was designed with the purpose of ®nding hidden areas that inates from an unknown source using unidenti®ed path- harbored microorganisms. This sampling plan required ways. As FDA reported in the Federal Register (1): greater ingenuity and the type of special knowledge that a End-product testing does not address the root causes microbiologist can bring to an HACCP team. of food safety problems; it is not preventive by design and The role of microbial testing in conducting a hazard requires that a large number of samples be analyzed to en- analysis. The development of an HACCP plan starts with sure product integrity. the identi®cation of the hazards that are reasonably likely MICROBIOLOGICAL TESTING IN AN HACCP to occur and to cause illness or injury in the absence of SYSTEM control. The National Advisory Committee on Microbio- logical Criteria for Foods explains in its ``HACCP Princi- An HACCP plan provides a safety-net of preventive ples and Application Guidelines'' (adopted 14 August measures to control hazards. The purpose of microbial test- 1997) (4) that during the hazard analysis, a ®rm must eval- ing is to con®rm that all possible avenues of contamination uate the severity of a potential hazard and its likely occur- have been identi®ed and that these avenues are being con- rence. A microbiologist can help the HACCP team assess trolled. To accomplish this, an HACCP program often a number of factors that can in¯uence the likelihood of changes the role of the microbiologist, and the location, occurrence of a hazard and the safety of a food product. timing, and frequency of sampling. Each of these changes These factors include water activity, pH, use of preserva- will be brie¯y discussed in order to provide a basis for a tives, and time and temperature pro®les. more detailed discussion of the role that microbial testing The FDA found during its HACCP Pilot Program that plays in validating and verifying an HACCP plan. the hazard analysis is often one of the most challenging The Microbiologist as a member of the HACCP steps in developing an HACCP plan. Normally an HACCP team. A ®rm's food microbiologist needs to be part of the team will develop a long list of potential hazards during HACCP team because of their speci®c knowledge and ex- the initial brain-storming phase of the hazard analysis. The pertise regarding hazard assessment, food safety control, team must then evaluate each potential hazard to determine and monitoring. They can contribute to the multidisciplin- which hazards merit being addressed in the HACCP plan. ary composition that is needed for an effective team and Firms often lack suf®cient data to determine whether a haz- for a team that will have the respect and con®dence of ard is likely to occur and whether the potential injury or management.
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