(Ivanhoe Newswire) -- Washing fruits and vegetables before you eat them
can reduce the risk of food poisoning and episodes of vomiting and diarrhea. But
now a new study finds washing alone may not be enough to remove disease-causing
bacteria. Researchers say irradiation may be the answer to killing off what
washing does not.
Scientists from the U.S. Department of Agriculture conducted the new research.
They say certain disease-causing microbes can play high-and-go-seek with
chemical sanitizers and remain in leaves of lettuce, spinach and other fruits
and vegetables. These microbes can turn into Salmonella and E. coli.
Irradiation exposes food to a source of electron beams, creating positive and
negative charges. It disrupts the genetic material of a living cell, essentially
killing off parasites and destroying other disease causing microbes. Study
authors say using irradiation on fresh fruits and vegetables could provide a
reliable way to reduce the number of food borne illnesses.
To test irradiation, study authors cut leaves of romaine lettuce and spinach
into pieces and submerged them in a mixture of E. coli. The bacteria were pushed
inside the leaves using a vacuum perfusion process. Then the leaves were treated
with a three minute water wash, three minute chemical wash or irradiation.
Study authors say washing with water was not effective at reducing the levels of
pathogen on either spinach or lettuce. The chemical treatment also did not
result in a significant reduction of E. coli. However, irradiation killed off
99.99 percent of the pathogen population on both the spinach and lettuce.
While some activist groups continue to speak out against irradiation,
researchers say 60 to 90 percent of consumers say they would buy irradiated food
when told about the benefits of the process and the endorsement of health
authorities.
SOURCE: Presented at 235th national meeting of the American Chemical Society in
New Orleans, April 6-10, 2008
