Detecting Salmonella bacteria on food currently takes considerable time – it’s days before results come in, which is often too late to stop infected food from reaching consumers. Researchers at Purdue have been developing a laser system that can detect Salmonella on food within 24 hours.
The beautifully-named BARDOT system (bacterial rapid detection using optical scatter technology) uses a red laser to illuminate bacterial colonies taken from food samples and grown on agar plates. A special sensor detects the scattering of the light coming from the colonies and compares the images against previously recorded light signatures of Salmonella. In tests using infected chicken, spinach, and peanut butter, the researchers showed BARDOT to be accurate to within 96%. Here’s a video of the optical Salmonella detector in action: