A group led by University of Florida researchers has developed a tracking system that could change the way companies ship produce, letting them know which items are closest to expiration.

Jeffrey Brecht, director of the Institute of Food and Agricultural Sciences' Center for Food Distribution and Retailing, studied strawberries from harvest in Florida and California to delivery to stores in Illinois, Washington, Alabama and South Carolina.

Colleagues from the University of South Florida, Georgia Tech and the industry collaborated on the project, funded by a $155,000 grant from the Wal-Mart Foundation, according to a news release.

The researchers placed two radio frequency identification devises, or RFIDs, in each pallet of strawberries as they were picked.

The devices allowed them to track the berries' temperatures from the field through pre-cooling, into trucks, to distribution centers and then to stores.

They theorized that if you know the quality of the produce and the temperatures to which it is exposed, you can determine which shipments to deliver first to stores.

They specifically looked at first in—first out. But they found that first expired—first out was a better way to handle produce.

Companies typically measure only the temperature of an entire truck.

But individual pallet temperatures can vary greatly depending on the time of day that the berries were picked and shipments loaded into the truck.

For example, berries picked in the cool of the morning and loaded into a refrigerated truck will stay fresher longer than berries picked in the afternoon heat.

Under ideal conditions, berries can maintain good quality for up to 14 days.

It can take as long as four days to move cross-country from the field to store.

If you improve the efficiency of post-harvest handling, you reduce waste and losses and that improves sustainability,” Brecht said in the release. “Because, of course, if you ship something to market that’s not going to end up being eaten by consumers, every single bit of input in growing it, harvesting, packing, cooling, shipping—everything is wasted.”