8 hour Listeria Test
An eight hour listeria test is what DuPont Qualicon has just annouced.
The new test is genetic-based and allows food companies to detect Listeria on environmental surfaces in only eight hours.
A spokes person for DuPont Qualicon says the new assay “is the first commercial application of Reverse-Transcriptase PCR for bacterial testing in food.” It is part of a suite of BAX(R) system products.
“This flexible test can give food companies clear, precise results at the end of a shift,” said Kevin Huttman, president of DuPont Qualicon. “With fast, accurate detection of Listeria, even at low concentrations, food processors get the information they need to take action sooner and release product faster.”
Listeria is found in many kinds of foods and us usually killed with proper cooking. Ready-to-eat products, such as hot dogs and deli meat, can become contaminated between cooking and packaging, however. The infection Listeriosis is caused by eating food contaminated with pathogenic Listeria monocytogenes. This illness is especially risky for pregnant women and immuno-compromised individuals. DuPont Qualicon said.
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Applications
The BAX® system detects all species of Listeria, even at very low concentrations (101 cfu/mL).
With reverse-transcriptase PCR, samples do not require the usual 24-48 hour enrichment in nutrient brotoh. Instead, Listeria cells are resuscitated by heating in the collection buffer solution for four hours, providing a jump-start to the process.
Validation studies on stainless steel using both the classic and Q7 models have shown that the BAX® system detected more positive results on spiked samples than the reference USDA FSIS culture method. In a panel of 58 strains across 7 species of Listeria and 52 strains of non-Listeria, the assay demonstrated 100% inclusivity/exclusivity.
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Approvals
The BAX® system 8-hour Listeria assay will be submitted to AOAC-RI for Performance Tested Method approval.
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