991055 Georgia Scientists Design Food Poison SensorOctober 16, 1999Atlanta, GA - Alarmed about deadly meat contamination episodes, Georgia Tech scientists have developed a sensor to detect E.coli, salmonella and other organisms before food reaches consumers, a researcher said. Scientists hope to use a tiny bacterial sensing device called a biosensor that developers said offers a fast, more accurate, cheaper way of spotting organisms in food before it leaves a packing plant. Food safety advocates, especially concerned about the nation's meat supply. have called for more protection against incidents like the listeria contamination in Michigan earlier this year that killed at least 14 people and caused several women to suffer miscarriages. Poultry and red meat are high priority items in current experiments, but tests that begin next month call for virtually every kind of packaged food to be studied, including seafood, dairy products and produce. The biosensor developed at Georgia Tech Research Institute can identify simultaneously any of a dozen disease-causing agents or pathogens and measure the degree of concentration in minute detail in hours, not days, and at a fraction of the cost of current laboratory methods. “The most significant advantage of the biosensor is the time reduction in assessing the presence of contamination,” research engineer Nile Hartman, a biosensor developer, said. Current tests can take up to 72 hours to show results. “The present method takes too long and has a lack of sensitivity,” he said. “The biosensor can do the job in less than two hours.” Lab tests have shown the biosensor to be extremely sensitive and researchers believe they can improve it even more. As for expenses, lab equipment can cost up to $20,000, the biosensor from $1,000 to $5,000. Federal regulations require that meat be tested for E.coli and salmonella, but there are no standards for bacterial concentration. Some food safety advocates blame the meat industry and politics for lack of government attention. Before it can be marketed, the biosensor must prove itself in a series of field tests, scheduled to begin its first three- to six-month phase in November at the Gold Kist plant in Carrollton, Georgia, about 50 miles (80 km) west of Atlanta. “One of the things we will be looking at is reproducibility of results,” Hartman said. “We will split a sample for testing with both of the technologies (the biosensor and current lab tests). For every 1,000 tests we do, we will look for the variation between results of the two methods.” Hartman said the initial field testing will be on poultry, but operations will be expanded to include red meat, dairy products, including soft cheeses such as Brie, produce and seafood, especially shellfish. Later on, “we would like to use the biosensor to address other food safety issues, such as those associated with insecticides, pesticides and growth hormones,” he said. It is not clear when the biosensor will hit the commercial market, with more lab tests scheduled after the field tests. When it does, it will compete with other techniques, including a DNA-based method and one using an electrochemical process. The integrated optic interferometric sensor technology on which the biosensor is based has been patented by Hartman and Georgia Tech Research Corp.
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