Simple Device Can
Ensure Food Gets to Store Bacteria-Free
Source of Article: http://www.voanews.com/english/Science/2009-03-12-voa25.cfm
simple new device can eliminate bacteria in packaged foods such as spinach, tomatoes
or lunch meat, ending worries about some food-borne illnesses.
Every day, people get sick from eating food that has spoiled or been
contaminated by bacteria, molds or viruses. Even if the food has been
properly prepared, these micro-organisms can get into it during the packaging
Kevin Keener, a food scientist at Purdue University, says he's found a way to
eliminate any bacteria from fresh foods after they've been packaged, in a way
that preserves their freshness. He does it by using ozone.
"Ozone is an oxygen with an additional oxygen molecule on it. It's
actually an O3... so standard oxygen in the air is an O2, and you add an
additional oxygen on it to make an O3," he says. "It's very
reactive molecule that will kill bacteria."
Ozone can be made from the air in a sealed package by zapping it with
"We take a voltage, and we increase the voltage up to literally
thousands of volts. And under those conditions, we can put a product such as
in the package inside of this voltage, and because of this voltage, it will
cause electrons to be removed from a small number of the molecules that are
present, and those electrons then will react and cause this formation of
ozone and other types of reactive oxygen molecules that will then attack
whatever might be in the air. So for instance, the bacteria are very
sensitive to these kinds of molecules."
The process doesn't heat up the food, and Keener says it doesn't affect the
taste. The best thing, he says, is that the process can be done after the
food is in its packaging, and it uses a surprisingly small amount of
"And ozone is well-established. It will kill spores. It will prevent
these bacteria from growing and so on," he says. "So there is a lot
of data that's already out there on the quality and effect of ozone
concentrations on different quality."
Keener is talking to some food manufacturers about trying his system on a
small scale. He says the biggest challenge will be scaling the technology up
to the point where it could be used on thousands of kilos of fresh produce
and meats daily.
His research is published in the journal LWT
- Food Science and Technology.