RFID Ensures Traceability

RFID is an up-and-coming technology that provides us with the opportunity to get as close as possible to real-time traceability in the produce supply chain. The technology, while not yet at optimal price or use levels in agriculture and food processing, comes closest to allowing us to track fresh fruits and vegetables through the supply chain. Slap a tag on a case, scan it before it leaves the farm and again when it enters and leaves the distributor and when it arrives at the retailer, and you have a very positive track system that also lends itself to reverse traceability. Instead of tracking materials through a factory-level manufacturing line, produce can be tracked through the entire food supply chain in an almost real-time manner.

Certainly, barcodes or even manual data entry to a centralized system can help with traceability. But neither has near real-time capabilities, nor do they allow us to attach measurement devices capable of communicating out-of-control conditions back to some type of control system. RFID seems to hold the greatest promise for this situation.

Remember principle four above, the one regarding monitoring microbial contamination levels in water? The next step is to find or develop some type of measurement capability, preferably one that can provide real-time measurement of bacteria in water. If such a device existed, and if it was cheap enough, it might be used by millions. Farmers, distribution centers, homes, retail outlets, and even restaurants could frequently check their water for harmful bacteria. Alas, the federal government has spent all of its money on visual inspection, so there is no known cheap real-time method of detecting harmful bacteria in water. It seems a little odd that we have spent billions on visual inspection but almost no money on development of a cheap water bioanalysis device.

So, how do we detect and measure the bacterial content of water? Our current measurement capabilities involve taking a water sample and sending it to a lab for analysis. The analysis is usually complete in two to four days, with a report most often delivered within a week or two. Think about that for a moment. Suppose there is a week lag time between taking the water sample and receipt of the lab results, and the results show high levels of contamination. Suppose that the water sample was taken at a farm. Does the farmer wait a week before shipping the produce? Probably not. Where is the produce after a week? Most likely the produce is in your refrigerator or in the salad you will eat in the next five minutes.

Suppose the water sample was taken from the produce section of your local supermarket? Where is the produce a week later? How many people have eaten it? Get the picture? There is simply no control over the safety—read quality—of food in our food supply chain. More importantly, there is no set direction for developing such control systems.

The theory is that the water activity levels in produce keep bacterial levels low. Water activity levels are more or less controlled by temperature. That’s why we have developed refrigerators. That is also why responsible supply chain members have developed what is called the cold chain. If a farmer harvests lettuce and quickly refrigerates it (many do), and the lettuce is processed and shipped in refrigerated trucks, boats, and planes (it often is), and it is delivered to refrigerated distribution centers and then into coolers in retail outlets, you have a cold chain. From a farm to an often very cool retail shelf, the produce is somewhat protected, its water activity level at a non-bacterial producing level.