What can we expect in the future for pathogen testing in poultry plants? Faster, more sensitive and more discriminating tests are around the corner, as technological advancements continue.
Look for improved enrichments, handheld and portable testing platforms, and organism identification with genetic fingerprinting, according to Troy E. Ayers of DuPont Qualicon, who spoke at the Poultry Processor Workshop about rapid microbiological testing applications for the food industry.
All this will help poultry processors shorten time to results, among other things, which would reduce costs and provide greater product flexibility in warehousing and inventory.
The three most popular rapid pathogen testing platforms today are the Lateral Flow Strip Test, Enzyme Linked ImmunoSorbent Assay (ELISA) and Polymerase Chain Reaction (PCR).
Real-time PCR technologies here today
Several real-time PCR technologies are now providing faster response time for corrective actions and troubleshooting due to positive results. These include probes (TaqmanTM), Molecular BeaconsTM and ScorpionsTM.
Detection is integrated with amplification, so no separate analysis phase is required, Ayers said. PCR processing, in fact, is completed in as little as 55 minutes, with most assays taking less than 90 minutes.
Scorpions is the latest technology, he said. “It gets a lot of attention due to specificity and accuracy and overall speed in generating PCR components and double-stranded DNA from single-strand DNA,” he explained.
Improved enrichment ahead
“One of the big things that everyone is working on now is enrichment methods,” Ayers said.
Improved enrichments will include increased specificity for the target organism and decreased time needed for enrichment. In fact, he said, short to no enrichment may be possible, as technological advancements continue in cell and DNA concentration and more sensitive detection.
Handheld and portable testing platforms
Portable or backpack-style PCR amplification testing units have generated a lot of interest and are in development by several companies. These portable instruments can run 24 to 32 tests to be taken to an offsite laboratory or the tests can be run in a processing facility, in essence creating a temporary laboratory there.
Organism ID coupled with genetic fingerprinting
Makers of micro-testing technology are working on ways to not only identify whether a sample is positive or negative for salmonella but go straight from that positive result to rapid typing.
Tradeoffs in testing methods
“In the past, the industry has relied on cultural methods as the gold standard for pathogen testing. While these methods are very laborious, they are not as expensive as rapid methods.
When considering the hold times that are required with cultural methods in order to release poultry products, however, the offsetting costs make rapid testing worthwhile,” he said.