Infrared used to instantly detect bacteria

Food processors are increasingly looking at faster methods of checking the safety of their products before they leave the plant. Consumer concern, tougher regulations and costly recalls are drivingthe trend. The new technique uses infrared spectroscopy on light reflected from the surface of the food to produce biochemical 'fingerprints' of any contaminating micro-organisms, such as bacteria, andrapidly estimate their numbers. The technique -- and a machine -- was developed by scientists from Manchester University as a means of improving the safety of processed foods across the industry. "Modern food processing is highly automated and efficient, but the way safety inspectors sample the products has hardly changed in half a century," stated David Ellis, a professorat the university who helped develop the technique. "At present, more than 40 different methods are available to detect and measure bacteria growing in meats. However, even the most rapid ofthese takes several hours, so results are always retrospective, which means that infected meat could get into the food chain." He believes that the new infrared equipment can be integrated directly into production lines. The technique does not involve injecting chemicals or touching the food itself. "It's relatively cheap, results are available in seconds and can be read by a machine," Ellis said. "This makes it ideal for on-line meat inspection." The team of scientists successfully tested the machine have already shown that the technique works in both chicken and beef -- which they say are two of the most difficult meats to check forsafety. Chicken and beef products are processed in different ways, and are typically contaminated by different types of bacteria. The method could therefore easily be applied to milk, ice-cream, cheese andother dairy produce, fruit juices and other foods, they conclude. The scientists are part of the University of Manchester's Laboratory for Bioanalytical Spectroscopy. External links to companies or organisations mentioned in this story: University of Manchester