New Salmonella Test
Agricultural Research Service (ARS)
by Sharon Durham
An innovative test to detect Salmonella in ready-to-eat meats has been developed by Agricultural Research Service (ARS) scientists. The preliminary test--still being evaluated by agency researchers--relies on PCR (polymerase chain reaction) technology to detect food-contaminating microbes on a molecular level.
Food technologist Jitu Patel with the ARS Food Technology and Safety Laboratory, and microbiologist Arvind Bhagwat with the ARS Produce Quality and Safety Laboratory, in Beltsville, Md., compared their laboratory-developed "molecular beacon" test to a commercial rapid-detection test currently in use. While both tests can detect Salmonella in eight hours, the laboratory test is less expensive than commercial kits.
To evaluate the new test's efficacy, the scientists artificially contaminated various meats (turkey, bologna and ham slices) and produce (mixed salad, sprouts) with S. enterica serovar Typhimurium and allowed it to incubate for 20 hours. Both tests were sensitive enough to detect contamination in the meat products at an estimated level of two to four cells per 25 grams. In comparing the tests after a relatively brief incubation period of eight hours, two to four cells of Salmonella were detected in the 25-gram samples of meat as well as produce.
The ability of the molecular beacon test to detect very low levels of Salmonella contamination in eight hours will aid the food industry in quality assurance, helping prevent recalls of contaminated meats and produce by stopping the products from being introduced in the marketplace. Detection of contaminated foods could be achieved within a work shift--before shipment takes place.
Agricultural Research Service (ARS) is the U.S. Department of Agriculture's chief scientific research agency.
I am asking if certain individuals are more suseptable to these types of virus, or can be more likely to get them on repeated occasions? Can we purchase these tests kits or lab test easily? Thank you very much. Regina
Regina,
The CDC estimates that 76 million people are sickened by various foodborne pathogens each year in the United States. Most of these people don't realize that they have food poisoning because the symptoms are flu-like. There are people at greater risk for developing serious complications from a Salmonella infection or other foodborne illness. Generally the high-risk groups are the very young, the elderly and people with weakened immune systems. Salmonella is a bacteria, so a person can be sickened by multiple infections. This is particularly the case with Salmonella because there are numerous strains of the bacteria.
The tests described here would normally be used by poultry processors and distributors. This research has not yet produced a marketed product to our knowledge. If we hear of a product that is available for consumers, we will notify our readers.