In general, two broad methods to detect foodborne pathogens exist. One would be the traditional culture method by which a sample is tracked and inoculated into a medium that allows any bacteria to grow. Then the bacteria are identified by conducting tests. The process typically takes from three to five days.
The second category of tests is grouped as molecular techniques, which are based on the DNA sequence of the organism. The technique called polymerase chain reaction (PCR) has become a very common method of taking samples, and the industry has much interest in developing these molecular techniques, says T.G. Nagaraja, university distinguished professor in the Department of Diagnostic Medicine/Pathobiology in the College of Veterinary Medicine at Kansas State University in Manhattan. PCR tests can identify a piece of nucleocapsid, which would be like a fingerprint of a particular pathogen, and amplify it.