I am sure everybody knows that washing fruits and vegetables at home under the tap is the best way to get rid of bacteria. However, according to new research presented on April 11 at the 235th national meeting of the American Chemical Society, grandma’s rule is not worthy anymore and washing alone just isn’t enough.

U.S. Department of Agriculture (USDA) scientists said irradiation may be the best way to remove pathogens inside fruits and vegetable.

The research comes after long debate over how to protect consumers from E.coli and other potentially deadly microbes, which intensified since the fall of 2006. At the time, at least 200 people across the nation became ill and three died after eating tainted spinach grown in San Benito County.

“Irradiation kills E. coli where chlorine doesn't. We used pretty aggressive levels of chlorine and found they weren't very effective at all. But when you have E. coli inside a leaf, and you irradiate it, the E. coli dies,” said Brendan Niemira, a microbiologist at the USDA's Eastern Regional Research Center in Pennsylvania who led the research, the Los Angeles Times reports.

Niemira said irradiation exposes food to a source of electron beams that inactivates parasites and destroys pathogens and insects in food. He strongly sustains the technique could reduce the numbers of food related illnesses, which affect 1 in 4 Americans every year. About 14 percent of the reported foodborne illnesses are linked to fresh produce, and spinach and lettuce are the biggest known culprits, causing 23 outbreaks since 1995

“When bacteria are protected -- whether they're inside a leaf or inside a biofilm -- they're not going to be as easy to kill. 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,” Niemira said.

However, Niemira said irradiation would not replace conventional safety measures, but could augment them. “Irradiation is not going to kill everything on every product all the time. It’s not a magic wand or a silver bullet. It’s intended as another tool.”

One problem still remains unsolved, as irradiation is not totally accepted by people. Many of them do not want to eat produce exposed to radiation, which could reduce vitamins and nutrients. Moreover, there are food safety experts who are skeptical about irradiation, which in high doses could cause cell damage that shortens shelf life.