RFID to Cut Food Waste in the Supply Chain

By Claire Swedberg

Ocean Mist and Costco are among the companies using a battery-assisted passive RFID-based Internet of Things solution from Zest Labs to automatically collect the time and location of goods.

Retailers typically lose an average of 15 percent of their income annually due to food loss or waste. In fact, up to 40 percent of the food grown in the United States is never eaten, according to the Natural Resources Defense Council (NRDC). Much of the food loss occurs at the farm level, while food waste takes place at a consumer's home, but some food spoils due to conditions throughout the supply chain. The cold chain is disrupted when refrigeration units in vehicles fail, delays occur on loading docks or an accident takes place.

If the food industry were able to eliminate this problem, the additional food provided could feed millions of people. In fact, the NRDC's 2017 report, "Wasted: How America Is Losing Up to 40 Percent of Its Food from Farm to Fork to Landfill," finds that the world population in 2050 will require 1.5 to two times the amount of food that we grow today, much of which we don't eat. In the meantime, food waste is reportedly responsible for 2.6 percent of U.S. greenhouse gas emissions.

Zest Fresh uses IoT sensors to monitor the handling and quality of each pallet of produce beginning in the field, enabling the matching of customers' freshness needs with the produce's actual freshness.

There are many government efforts underway to address food waste at the global, national, state and local levels, according to Andrea Collins, NRDC's sustainable food systems specialist. "Additionally, many businesses are focused on cutting their waste. Many of the solutions involve technology, especially when it comes to forecasting demand, managing product, measuring what goes to waste and generally maximizing the utilization of whole products."

Several food companies are addressing the problem of food waste in the supply chain with an RFID-based solution known as Zest Fresh, provided by California company Zest Labs. The wireless sensors and cloud-based software help users to track the conditions of their temperature-sensitive products as they move from the field to the store, thereby identifying when conditions fall outside of acceptable parameters. The solution also provides predictive analytics to recommend corrective action when a temperature excursion is detected.

Ocean Mist is using the technology to automate the tracking of its fresh vegetables from multiple growing regions in California as produce is harvested in fields and moved through the packing house, with a goal toward maximizing product freshness. The company is monitoring the times at which produce is cut and cooled, along with dwell times throughout the supply chain. That data provides the firm with visibility into produce conditions and status, and operational efficiency.

Costco Wholesale is using the technology to track produce from its California suppliers to warehouses on the West and East Coasts. The company aims to gain analytics data about the supply chain and thereby identify ways in which it can ensure the optimal freshness of product arriving at stores.

Andrea Collins

Zest Labs, an agricultural technology firm in San Jose, Calif., was founded as Intelleflex, then changed its name to reflect its product brand, Zest Fresh, in October 2016. The system uses a battery-assisted passive (BAP) UHF RFID protocol that features a longer read range than purely passive RFID and supports the continuous collection of sensor data.

The temperature of food in the supply chain directly affects its shelf life, according to Peter Mehring, Zest Labs' CEO. "The food industry has a misperception that everything harvested on the same day has the same shelf life," he explains. A vegetable or fruit that is delayed or incompletely processed will have a shortened shelf life.

Another misperception, Mehring says, is that the party who has the product in hand is responsible for its spoilage—when, in fact, the damage might have been done much earlier in the supply chain. For example, he adds, a pallet of fresh strawberries has a typical shelf life of 12 days. However, that same fruit could lose three days of shelf life by sitting in a field at 80 degrees Fahrenheit for three hours. Visual inspection would not detect that problem.

Having provided RFID-based temperature sensors for the agriculture industry for several years, Intelleflex began building its own software around 2012 to capture and manage RFID read data, since the company found a shortage of software providers for its technology and application. "We decided we needed to build our own software and offer an end-to-end solution," Mehring says. The company worked with Wal-Mart from 2013 to 2017, though it has since filed a lawsuit against the retail giant for trade-secrets violation. In 2018, Zest Labs' other customers began piloting or deploying the technology, including Ocean Mist and Costco.

Peter Mehring

With Zest Fresh, users first capture sensor-based data in the field. When a product (lettuce, for example) is harvested, it is packed in boxes and a Zest Fresh sensor—containing a built-in UHF RFID tag, a temperature sensor and a battery—is placed in the box along with the produce. Users typically deploy a sensor in a single box on each pallet to track the conditions for all goods on that pallet.

The company's TMT-8500 (ZIPR Tag) sensor can be configured to capture temperature readings at a user's preferred intervals, and to go to sleep between measurements. The sensor's coin-cell battery typically has a three-year life-span, with each tag able to hold up to 3,000 data points. As products move from one location to another, such as from the field to a cooling area, the sensor tag is interrogated by a handheld RFID reader or by a fixed portal or gateway. The tag can also be interrogated by a reader mounted on a forklift.

When the tag responds, it transmits its own unique ID number, as well as all temperature measurements taken since the last reading. This data is then stored in Zest Fresh's cloud-based software, which users can access from an Android- or iOS-based desktop or mobile device. The data collected can not only alert users to a problem, but also provide historical data for analytics purposes, by identifying trends, such as prolonged waits occurring at specific locations, or the warming of goods at certain times

The system enables supply chain members to capture data without stopping to seek a data logger or record temperature information manually. "We give them the visibility that captures the data automatically," Mehring says. Users can identify when conditions fall outside acceptable parameters, then address that problem by taking corrective action, such as moving a product ahead of other inventory for precooling so it will reach a store with sufficient freshness.

Thus far, Mehring reports, those using the technology have expressed surprise upon finding that their operations are not as consistent as they had thought they were. By viewing data regarding current conditions and historical information, he adds, companies can modify their operations to become more efficient and ultimately improve the shelf life of the goods they sell.

Greater efficiency in the supply chain can also reduce the waste of energy consumption and feed more people, Mehring notes. Moreover, trends data provided by the software enables companies to identify bottlenecks or inefficiencies, and also helps create metrics for more accurate shelf-life calculations. This data can be used to identify a problem's source, as well as to prove where problems did not occur for members of the supply chain (meaning that a party was not responsible for early spoilage). To date, Mehring says, the system has proved to reduce retail waste by about 50 percent or more.