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Environmental monitoring: indicator organisms and pathogen testing.

Food safety and pathogen testing.

Establishing a comprehensive environmental monitoring plan can help facilities take a preventative, proactive approach to correcting potential food safety testing issues.

Education and awareness about the measures your facility can take help ensure food safety. In this series, we explore best practices for implementing an effective environmental monitoring program using our Environmental Monitoring Handbook. This resource has been developed with Cornell University and other industry experts. It provides guidance on how those in the food and beverage industry can build and implement a holistic approach based on scientific advice and industry best practices.

In this article, we look at an essential part of this preventative approach, namely testing for indicator organisms and pathogens in food processing environments. These monitoring methods can be used to determine the general hygiene of food processing areas.

Testing for indicator organisms.

Indicator organisms are a group of organisms that reflects the general microbiological condition of a food or the environment. Indicator organism monitoring is conduced to help monitor or validate sanitation and process controls. It provides information about the microbial ecology of food manufacturing areas and assesses post-processing contamination risk The microorganisms tested represent the overall condition of the food environment where the food is being processed.

Aerobic Plate Count (APC), or Total Plate Count (TPC), is one of the most common indicator tests. It provides information about the total population of bacteria present. Simply put, if a manufacturing process is under control, the number of indicator organisms will also be in control. APC counts above a certain threshold suggest that the sanitation of that specific environment was ineffective and/or improperly performed.

Enterobacteriaceae consists of a diverse group of bacteria including coliforms and some pathogens such as Salmonella.

Enterobacteriaceae testing serves the same purpose as coliform testing in that it indicates:

  1. Improper cleaning
  2. Unsanitary conditions
  3. Post-process contamination

Testing for pathogens.

Pathogen tests check for the presence of a specific microbe. Because this microbe can be difficult to find, it is recommended that additional methods be used to validate cleaning and sanitation procedures, such as adenosine triphosphate (ATP) tests and total plate count.

The primary goal for pathogen environmental monitoring programs is to eliminate pathogens and the associated risks for foodborne illnesses and recalls. Foodborne pathogen contamination of finished products typically occurs at a low frequency, which can make finished product testing alone an ineffective strategy for ensuring food safety. Using a pathogen environment monitoring program can help identify contamination sources before they reach a finished food product.

Environmental monitoring is typically used in facilities that process ready-to-eat (RTE) products or in facilities that handle RTE products. While many different pathogens can cause foodborne illness, only a few are linked to food processing and handling environments. Key pathogens targeted for environmental monitoring programs include Listeria monocytogenesSalmonella, and Cronobacter spp.

For both indicator organisms and pathogens, a program should be established with sampling procedures and frequency, appropriate test methods, results interpretation, and corrective action procedures. Frequency should be determined and may vary between facility, commodity, and target analyte. Sampling sites should be mapped out with the goal of finding potential issues in the most likely sources of contamination. Quantitative results will be useful in establishing baselines and identifying trends over time.

Learn more about environmental monitoring

To learn more about the importance of environmental monitoring, download our Environmental Monitoring Handbook by visiting this page. For more information on 3M Food Safety testing product solutions, contact a representative by filling out the form below.

Stay tuned for the final of this series to learn about the steps you can take to be more proactive about food safety testing in your facility.


About the Author

[enBio=Across the globe, 3M helps companies and individuals succeed every day. All while contributing to true global sustainable development through environmental protection, corporate and social responsibility and economic progress. We are applying our science to make a real impact in every person's life around the world.],[enJob=Food Safety Division],[frBio=Chaque jour, 3M aide les entreprises et les gens à réussir. Tout cela en contribuant au développement durable réel par le biais de la protection de l'environnement, la responsabilité sociale en entreprise et le progrès économique. Nous appliquons notre science afin de faire une différence réel dans la vie de chaque personne dans le monde.],[frJob=Division de la sécurité alimentaire]

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