August 27, 2010

Modern imaging detects Campylobacter in 24 hours

USDA study has revealed a type of high-tech imaging to be used to determine the Campylobacter from other micro-organisms as quickly as 24 hours after a sample is placed on solid media in a Petri dish.

The researchers, with USDA's Agricultural Research Service (ARS), used technology called hyperspectral imaging, which combines digital imaging with spectroscopy, to provide hundreds of individual wavelength measurements for each image pixel.

Micro-organisms grown on solid media carry unique spectral fingerprints in the specific portion of the electromagnetic spectrum. A hyperspectral imager identifies these fingerprints by measuring light waves that bounce off or through these objects.

This "sensing" technology, which was nearly 100% accurate with pure cultures of the micro-organisms, could be used for the early detection of the presumptive food-borne pathogen colonies in mixed cultures. The researchers are working toward developing a presumptive screening technique to detect Salmonella and Campylobacter in food samples.