Post-cleaning testing: A step toward a safer food processing environment

In the United States alone, Listeria and Salmonella are among the leading causes of foodborne deaths, hospitalizations, and illnesses.

Salmonella spreads through cross contamination of raw ingredients, utensils, workers' hands, clothing, and equipment. The ability of this pathogen to survive in a wide range of pH levels as well as temperatures makes it a major organism of concern. Listeria is another common pathogen found in food processing environments. It persists within biofilms on equipment, utensils, drains, etc.

Importance of pathogen detection post-cleaning

Testing food processing environments after cleaning is useful to not only ensure low pathogen levels, but also to validate sanitation practices in place at your facility.

While such tests do not guarantee quality of food, they work very well to provide data on indicator and spoilage organisms of concern that threaten food safety. More importantly, when used correctly, these tests provide data in a timely manner.

Listeria and Salmonella tests for environmental samples

Specifically designed to monitor the presence of Listeria and Salmonella, InSite™ tests provide results in 24-48 hours and offer a cost-effective way to achieve consistent, reliable results.

InSite™ Environmental Listeria Species Test

The InSite™ Listeria test is able to detect most common Listeria spp, including L. monocytogenes, L. innocua, L. ivanovii, and L. welshimeri at levels <10 CFU.

The test device is self-contained and includes a chromogenic liquid media which is formulated with antibiotics, growth enhancers, and color changing compounds specific to Listeria species. For this device, a color change from yellow or amber to grey or black is considered a presumptive positive.

There may be cases when bacteria such as Enterococcus spp. in high numbers give the same results as Listeria species. While verifying Listeria’s presence is recommended via PCR, ELISA or lateral flow methods, the color change caused by presence of other organisms still indicates the need for improved cleaning and sanitation.

InSite™ Environmental Salmonella Species Test

Similar to the Listeria test, the InSite™ Salmonella test is a self-contained test intended for testing food contact surfaces and other processing equipment in the facility after cleaning.

The test device includes color changing compounds specific to Salmonella species: a color change from purple to bright yellow is considered presumptive positive.

To prevent the growth of competitive microflora, the test contains selective agents to provide nutrients specific to Salmonella’s growth.