InSite Salmonella is a swab test which contains a medium formulated with growth enhancers and chromogenic compounds which changes color when Salmonella species are present in the sample.
A color change from purple to bright yellow in 24 hours is considered a presumptive positive.
Results cannot be considered presumptive negative until 48 hours incubation and presumptive positives can be confirmed using selective Salmonella agar plates or a recognized confirmatory method.
Quicker results, quicker reaction
Lauren Roady, marketing manager at Hygiena, said by knowing results sooner, processors can react to environmental contamination earlier, preventing lot contamination or product recall.
“Also, InSite Salmonella is much easier to use than other kits because it doesn’t require any measurement, mixing, or pipetting to run the test,” she told FoodQualityNews.
“The media is all pre-measured and self-contained within the environmental sample collection device, so there is virtually no room for operator error.”
The test device eliminates sample preparation items, saving material and labor costs, said Hygiena.
Other environmental Salmonella species test kits require steps including measurement and mixing of media, sample enrichment, and transfer of enriched sample to the test device, said the firm.
It features a large 2.5 inch foam swab for maximum sample pickup and is sensitive to 1-10 CFU.
ATP tests to monitor environment
Roady said most food processors regularly monitor the environment for general cleanliness using adenosine triphosphate (ATP) tests.
“Monitoring for environmental pathogens is part of risk-based preventive control monitoring program, so the frequency and volume of environmental pathogen testing depends on risk, budget, and quality commitment,” she said.
“However, the rules proposed by the FDA for FSMA suggest that there may be a greater emphasis on preventive control monitoring for high-risk food processors, such as Ready-to-Eat, dairy, meat, produce and others.”
The user swabs a 12x12 inch surface after cleaning, replaces the swab in the tube, and then incubates the device.
After pre-enrichment, the device is activated, releasing the pre-measured selective media into the tube and incubation is continued.
If Salmonella species is present in the sample, the medium in the test will change from purple to bright yellow. If there is no color change by 48 hours, the sample is presumptive negative.
For environmental montoring, food processors are looking for rapid tests that are easier to use, said Roady.
“I think most food safety and sanitation professionals will agree, the most simple and easy-to-use environmental monitoring tools are ATP monitoring systems,” she said.
“New test kits for microbiology testing, that are just as easy to operate as an ATP test, are making environmental microbiology more approachable for in-house food labs.”