Washington, DC--Hyperspectral imaging can be used to distinguish the food-borne pathogen Campylobacter from other microorganisms as quickly as 24 hours after a sample is placed in a Petri dish, according to a study published by U.S. Department of Agriculture (USDA) scientists.
Large spectral range
The researchers, with USDA's Agricultural Research Service (ARS), used hyperspectral imaging (which combines digital imaging with spectroscopy) to provide hundreds of individual wavelength measurements for each image pixel. The hyperspectral imager has a spectral range that extends from UV to near-IR.
Campylobacter infections in humans are a major cause of bacterial food-borne illness. Growing Campylobacter directly on solid media has been an effective method to isolate this organism, but distinguishing Campylobacter from non-Campylobacter microorganisms is difficult because different bacteria can often look very similar. Normally, isolation and detection for identification of Campylobacter from foods like raw chicken involve time-consuming or complicated laboratory tests that may take several days to a week.
The USDA technique, which was nearly 100% accurate with pure cultures of the microorganisms, could be used for early detection of presumptive Campylobacter colonies in mixed cultures. The researchers are working toward developing a presumptive screening technique to detect Salmonella and Campylobacter in food samples.
Findings from this study were published in the journal Sensing and Instrumentation for Food Quality and Safety. This research supports the USDA priority of ensuring food safety.
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John Wallace | Senior Technical Editor (1998-2022)
John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.