The U.S. Department of Defense is reviewing the results of a two-part, five-year research project conducted by members of academia and RFID industry to study the tracking of food rations destined for military troops, and the shelf life based on storage and transportation conditions of those rations. The project aimed at determining whether software along with temperature sensors and RFID technology could be employed to monitor the varying environmental conditions to which rations have exposed, and to revise expiration dates accordingly. By doing so, the system could also then instruct staff as to which items should be shipped to troops, where, to ensure nothing spoils or expires.
The solution poses potential benefit not only for the military but also for the commercial market. That’s due to the fact that an RFID-based system, and software interpreting sensor-based data from that system, could ensure the conditions of perishable items are tracked and their movement to retail stores is modified according to those conditions, thereby ensuring fewer items spoil or must be discarded before they reach the consumers’ plates, says one of the project’s co-directors, Ismail Uysal, who is also director of the USF RFID Center for Applied Research at the University of South Florida (USF), and assistant professor of electrical engineering.
Uysal says the study has proven that technology is capable of enabling the military or the commercial food industry to better ensure products are not wasted. And that is not a small problem, he says. According to a paper published in 2009 by researchers affiliated with National Institutes of Health (NIH), as much as 40 percent of food in the United States ends up not in consumers’ kitchens, but discarded—in large part due to spoilage somewhere in the supply chain, or as a result of conditions in the supply chain. He says the researchers’ next goal, therefore, is to help educate the market about the value of such a solution.
The team has consisted of faculty members not only at the University of Florida but also from the Florida Polytechnic University (Florida Poly) and Georgia Institute of Technology and the CEO of technology company Franwell. Researchers used off-the-shelf temperature-sensing tags and readers, and developed software with an algorithm developed to identify the expected expiration (spoilage) date of a food product based on the conditions it was exposed to. The software approach, Uysal explains, differentiates between a static shelf life identified by an expiration date (the date stamped on a food ration based on optimal storage conditions) and a dynamic shelf life that changes according to the items conditions.
The first phase of the project began in 2008 (see Researchers Seek to Reduce Wastage for First-Strike Rations) and consisted of creating the algorithms that would enable the software to calculate shelf life, as well as testing the available off-the-shelf models of semi-passive RFID sensor tags. The project had initially been intended to end in December 2012, but was extended nearly a year so it could measure how long it took for the food to spoil. The second phase studied Meals Ready to Eat (MREs) as well as First Strike Rations (FSRs), which are lighter in weight. MREs and FSRs consist of prepared foods (for example, beef ravioli in meat sauce and pork sausage in cream gravy ) that are vacuum-packed in pouches made of plastic film. The foods are packaged and treated with preservatives such as ascorbic acid (vitamin C) so that they have shelf life of up to three years for MREs and two years for FSRs. The Defense Logistics Agency buys approximately 30 million MREs annually for all of the U.S. armed forces, and spoilage costs the U.S. military millions of dollars a year.
Despite a common perception among members of the military as well as the general public that MREs and FSRs have shelf life that can last for years, or even decades, the researchers demonstrated that MREs and FSRs can actually spoil. The team measured shelf life based on sensory or nutritional degradation of the meal such as flavor or aroma changes or textural alterations due to water migration from one part of the food item to another.
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Ways to extend the shelf life and how to best handle fresh fruits and vegetables were also tested. The group worked with broccoli, romaine lettuce and vine-ripened tomatoes, says Jeffrey Brecht, co-team leader and director of the Center for Food Distribution and Retailing at University of Florida’s Institute of Food and Agricultural Science. “We investigated modified atmosphere packaging (MAP) and ethylene scrubbing as two possible ways to overcome what we hypothesized to be incompatibility problems with other fruit and vegetables shipped in the mixed loads.”
Brecht says the group found that MAP would allow vine-ripened tomatoes to be transported at higher temperatures that avoid chilling injury and associated loss of flavor. “For broccoli and romaine lettuce, we found that the problem was actually that the quality specifications don’t address the freshness of those products at the time the marine containers are loaded.” He adds, “We also showed that MAP in general mitigates potential problems with ethylene produced by one product negatively affecting another product.”
The project’s second phase also tested hardware as well as the software that uses the temperatures and shelf-life algorithms to identify which rations get shipped when and where in order to get them to the troops in time. So far, the system has been tested in temperature-controlled labs, but not in a real-world setting. That kind of pilot could be approved by the DOD if it determines to move forward with the technology.
According the published report, the hardware used in the project consisted of off-the-shelf RFID readers and semi-passive temperature-sensing tags currently available commercially, including CAEN RFID‘s A927Z RFID and RT0005 tags, a PsionWorkabout Pro 2 handheld attached to a CAEN A528 RFID reader and a Motorola Solutions MC9090-Z handheld reader, although Uysal says any EPC UHF RFID reader would work. He declined to indicate the results of performance tests on the tags, however he says two tag-reader combinations were recommended to provide the best performance in the report now being reviewed by the DOD.
Researchers used a server dedicated to the standalone system on which the software they developed operated. Tags could be read periodically to capture sensor data, and the tags logged temperature measurements in the meantime at periodic intervals. If the system were implemented by the DOD or a company in the food industry, the data could help route goods from distribution centers. For instance, when the goods arrived at a warehouse, Uysal says, handheld or fixed readers could capture the unique ID number and sensor data from a tag applied to a loaded pallet, and that data would be sent to the dedicated server operating the system software. The software links the ID number to the type of product on the pallet as well as its history, such as when it was first packaged, and the temperature conditions it was exposed to.
When an order is then placed for specific goods, Uysal says, the software could determine how long the items would take to reach the location for which the rations were ordered, and thereby calculate which pallet load should be shipped. That pallet is then indicated on the shipping order, with a human-readable number linked to the RFID tag’s EPC number, thereby enabling staff to identify the right pallet either visually or with an RFID reader.
The solution moves a step beyond the concept of First in First Out (FIFO), in which goods are shipped simply according to the dates at which they were received, or even First Expired First Out (FEFO), according to the expiration data assigned to that item based on optimum conditions. The solution has large implications for the commercial market, says Uysal, and he hopes to communicate the benefits to members of the food industry such as retailers and producers.
According to a report published in 2012 by researchers working for the U.S. Department of Agriculture (USDA), Americans discarded $165.6 billion worth of food, and most of that waste was due to spoilage before the food can be consumed. In the future, he envisions a system in which stores could use (and provide for their customers) handheld readers linked to a server with software that identifies an item’s actual expiration date based on its storage and transportation conditions. In that way they would be able to identify very quickly whether the product needs to be sold right away, and perhaps even discounted for consumers to ensure it gets to the buyer’s plate before it spoils.
Uysal adds that not only retailers, but producers serve to benefit from such a solution by ensuring less merchandise is wasted, and also reducing the cost of shipping goods that may spoil before being sold. Uysal will be presenting the results of the study at RFID Journal LIVE! 2014 in Orlando, Fla.