Researchers at the Purdue University in Indiana have developed a new method for detecting foodborne pathogens, potentially paving the way for faster disease control and fewer infections.
The process concentrates pathogens like salmonella by using hollow thread-like fibers that filter out the cells. That filtering process is speedier than conventional methods, and could make it possible to routinely analyze food or water samples to screen for pathogens within a single work shift at food processing plants.
"This approach begins to address the critical need for the food industry for detecting food pathogens within six hours or less," said Michael Ladisch, professor of agricultural and biological engineering at Purdue University. "Ideally, you want to detect foodborne pathogens in one work shift, from start to finish, which means extracting the sample, concentrating the cells and detection."
Specifically, the new system enables researchers to carry out cell concentration – the first step in detecting pathogens – within one hour, compared to a day for the standard method now in commercial use, Ladisch said.
Findings showed the system was able to concentrate inoculated salmonella by 500 to 1,000 times the original concentration in test samples. This level of concentration is required for accurate detection.
Another finding showed the system recovered 70% of the living pathogen cells in samples, Ladisch said.
Though reported foodborne illnesses have been on the decline recently, the number of laboratory-confirmed salmonella cases did not change significantly in 2012 compared with 2006 to 2008, according to a Centers for Disease Control and Prevention report, showing continued room for improvement.
The researchers say the technique could be performed during food processing or vegetable washing before the products are shipped. It must now be tested by the U.S. Department of Agriculture before it is ready for commercialization.
The complete study will appear in the November issue of the journal Applied and Environmental Microbiology.