A 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 process.
Now 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 electricity
"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 electricity.
"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.