Lettuce trails

A head of lettuce can have a long journey from the field to your salad bowl, but a new locally developed project can tell you just where that lettuce came from, providing a safer way to regulate the leafy green industry.

The project by the University of Arizona Yuma County Cooperative Extension uses a radio frequency identification (RFID) tag and GPS technology to store and transmit information about the crop.

This results in almost instant traceback of leafy greens. That way, if there's ever a health scare associated with the crop, shippers will be able to tell where it came from, making it safer for consumers.

"This is a huge thing in terms of novel creativity and innovation in terms of traceback in the world," said Kurt Nolte, Extension director and project leader.

 As the lettuce is cut, it's loaded into boxes to be shipped. The boxes have a sticker with the RFID tag. The tag has what Nolte calls essentially a "thumb drive," about the size of a pinhead, where it stores information. Then, as the box travels on a conveyor belt, it passes under an antenna that records the information associated with the crop, he said.

From a laptop computer, also in the field, the information is transmitted back to an office or base computer where it's recorded, providing a database of the crops that's easily accessible in the future.

The RFID tags on the boxes and the laptop computer that transmits the information are located out in the field and don't require an additional person to run them - keeping the process fluid.

The initial cost will be about $5,000 plus 5 cents for each RFID tag. But as the program gains popularity, the cost of the tags will go down, Nolte said.

The idea came from an E. coli outbreak in 2006 that was eventually traced back to spinach grown in California.

Nolte said it was a "watershed moment" for the industry. "We needed to find a way to trace lettuce back to its origin."

With a $30,000 grant from the Arizona Department of Agriculture, Nolte worked with consultant Joel Spencer to develop the traceback program.

It took about two years to develop, but in March, Nolte and Spencer were able to apply the technology to a lettuce harvest in Yuma County. There is currently a patent pending on the technology.

For now, traceback can vary by the shipper. However, Nolte said, there will be mandated traceback by 2012 in the leafy green industry with the Produce Traceability Initiative.

Nolte said after a problem such as an E. coli outbreak occurs, it can take months to traceback a crop - but that's about to change.

He said you can know where the lettuce came from within about 5 to 10 feet and "within seconds."

"Quick is important in terms of finding locations for a potential problem," Nolte said. "This system could streamline traceback to a location rapidly."

Nolte said quickly providing the location will help restore confidence in the industry - something that quickly dissipates as consumers cut ties with the crop associated with a problem.

But it's not just the location of the crop. Every attribute that's associated with a crop is stored in the RFID tag, he said.

Important information such as who cut it, the time it was cut and management practices in growing it are stored in the chip and will be accessible, Nolte said.

For growers and shippers, that will help pinpoint the location of a crop if there's a problem, but Nolte said the technology will one day be a part of consumers' lives.

He said eventually, a consumer will be able to pick up a head of lettuce in the grocery store, scan it and be able to access all of the information.