Life Technologies' Salmonella pooling kit has been backed by a French certification system.
The AFNOR Certification system issued the NF Validation quality mark for the Pathatrix 10 Pooling Salmonella spp. kit linked to MicroSEQ Salmonella spp. detection kit.
Pathatrix 10 Pooling Salmonella spp. kit supports pooling of up to 10 enriched samples into a single preparation, which is assayed as an individual test in the real-time polymerase chain reaction (PCR)-based MicroSEQ Salmonella spp. detection kit.
A negative result indicates all representative samples are negative, while a positive result shows that at least one sample is positive and the enriched samples must be re-run through the Pathatrix and the MicroSEQ assay individually.
How it works
The link is a heated lysis step, Nir Nimrodi, general manager of the animal and food safety business for Life Technologies, told FoodQualityNews.com.
“The IMS beads with the Salmonella cells attached to it, are treated by a heated lysis step (lysis buffer) to release the DNA. The released Salmonella DNA is detected by real-time PCR using the MicroSEQ Salmonella spp real-time Detection kits,” he said.
The firm said the validation supports alternatives in pooling protocols and enables reduced costs for the European food safety market.
Pathatrix Auto in combination with the MicroSEQ Salmonella spp. detection kit obtained AOAC validation in 2013.
It is approved for testing on meat, raw beef, cooked delicatessen meats and ready-to-reheat foods as well as dairy products, including milk powders, infant formula, and milk.
Each kit includes one vial of antibody-coated beads and sterile, single-use plastic consumables for 50 pooled tests (500 individual, enriched samples).
Nimrodi the pooling of 10 samples is the maximum pooling for the Pathatrix instrument and there are no plans to go for a higher level of pooling.
“You can only pinpoint the positive sample to rerun every sample individually when the pool is showing a positive result,” he said.
“From time and cost point of view, this is very effective, as food safety testing is a negative screening. As HACCP plans are set up in food production companies, only a very low level of positives is seen (1%) during laboratory screening, so re-testing is only needed very few times.”
Reduce downstream testing cost
The workflow can reduce downstream testing costs by up to 90% without trading performance, said Nimrodi.
“The fact is that using a wet pooling system like the Pathatrix allows you to run only one detection for 10 samples instead of 10 detections, meaning 1 PCR instead of 10, or 1 selective plating analysis instead of 10x,” he said.
“We mainly see three types of detection in the market: by real-time PCR, by selective agar plating, by immunoassays. The costs for each methodology are depending on the workflow and kind of food matrices.
“The fact is that using a wet pooling system like the Pathatrix allows you to run one PCR for 10 samples instead of 10 PCRs.”
The approval is the result of Life Technologies’ acquisition of Matrix Microscience and its Pathatrix Auto platform in January 2012.
Pathatrix Auto System and MicroSEQ food pathogen detection methods are for testing of food and environmental samples only.