USDA eyes irradiation for vegetables

NEW ORLEANS, April 11 (UPI) -- U.S. Department of Agriculture scientists said irradiation may be the best way to remove pathogens inside fruits and vegetables.

A report presented by USDA scientists this week at the national meeting of the American Chemical Society said chemical sanitizers aren't always effective at reaching bacteria that have made their way inside the leaves of lettuce, spinach and other vegetables and fruit. Microbes can also organize into biofilms that coat fruits and vegetables with multiple versions of infectious, disease-causing bacteria, such as Salmonella and E. coli.

USDA microbiologist Brendan A. Niemira said irradiation exposes food to a source of electron beams that inactivates parasites and destroys pathogens and insects in food. He said the technique could reduce the numbers of foodborne illnesses reported each year.

"When bacteria are protected -- whether they're inside a leaf or inside a biofilm -- they're not going to be as easy to kill," Niemira said in a statement. "This is the first study to look at the use of irradiation on bacteria that reside inside the inner spaces of a leaf or buried within a biofilm."