He added that to date the U.S. Food and Drug Administration has approved the use of ionizing irradiation on fresh produce for use on only lettuce and spinach, so the research team studied only those specific leafy greens.
"We selected electron-beam processing as this is the technology that has the potential for worldwide use because it is based on electricity and is basically a switch-on, switch-off type technology," Pillai said.
For their experiments, the team obtained iceberg lettuce and baby spinach samples from local grocery stores, then inoculated the samples with rotavirus and poliovirus and exposed the samples to defined electron-beam doses.
Pillai said results showed that electron-beam irradiation was able to inactivate both rotavirus and poliovirus on lettuce and spinach. The team's quantitative health-risk estimates showed that even if a serving size of about 14 grams of lettuce contained 140 polio virus particles, electron-beam irradiation at 3 kilograys (kGy) will reduce the risk of infection from greater than two in 10 persons, or 20 percent, to approximately six in 100 persons, or six percent. A kilogray is measurement unit of an absorbed ionizing radiation dose.
Similarly, according to study results, for a serving size of spinach contaminated with approximately 10 rotavirus particles, electron-beam irradiation at 3 kilograys will reduce infection risks from about three in 10 persons, or 30 percent, to about five in 100 persons, or five percent.
Pillai, however, noted that electron-beam irradiation is not meant to be used as a "stand-alone" or "clean-up" technology.
"The technology has to be used in conjunction with good agricultural practices in the fiel
|Contact: Dr. Suresh Pillai|
Texas A&M AgriLife Communications