Researchers at the Georgia Tech Research Institute have developed a device that can identify food contamination in a matter of hours and can tell you which of 12 "baddies", including the dangerous E.coli 0157 and salmonella, are present. The device uses the latest technology, integrating optics, immunoassay techniques and surface chemistry to give a result in under two hours. This might be slow if you are waiting to eat your Chinese takeaway, but is quick compared to existing tests which can take up to three days.
