As the potential of blockchains rumbles beyond the financial realm, Walmart is the latest to trial the technology in hopes it can track food through the supply chain and pick out and recall tainted products.
As Ars previously reported, blockchain technology is essentially a ledger of chunks of data – blocks – linked together using validation codes. Each block’s code references that of the block before it, creating an unbroken, sequential chain. So all blocks are kept forever in the order they were added, providing a kind of built-in validation system – or as Ars previously described it, as a “supplied audit trail” – locked against tampering. In fact, the chain doesn’t have to be stored in a master location, but can instead be split across multiple computers, still creating a linked record.
The technology was initially applied to secure money transactions, underpinning the rise of Bitcoin. But recently there has been a push to use it in other industries. In February, Ars reported that IBM was offering blockchain-as-a-service for businesses, especially those involved in logistics, such as those in the food industry. The idea is that food products can be tracked as they move from farms and factories to store shelves. Using tags and sensors, a product’s location, temperature, and other metrics can be recorded in a blockchain ledger at every step.
Coincidentally, Walmart took up that offer. In October, the commercial giant teamed up with IBM and Tsinghua University in Beijing to track pork in China as it moves from farm to shelf. Walmart also tracks packaged products in the US using blockchains. Walmart hopes that if something goes wrong, such as the meat being shipped with contamination or spoilage during delivery, the affected batches can be quickly identified, tracked and moved out of reach of consumers.
“It gives them the ability to have accounting from origination to completion,” Marshal Cohen, an analyst with researcher NPD Group Inc., told me. Bloomberg. “If there is a problem with an outbreak of E coli, this gives them the opportunity to immediately find where it came from. That is the difference between days and minutes.”
For a retailer like Walmart, which serves 260 million customers a week, an efficient tracking system also means the difference between picking up a few affected shipments and needlessly discarding products from hundreds of stores as a precaution.
This week, Walmart offered an update on the trial. “So far everything is going smoothly and as expected,” Frank Yiannas, vice president of food safety at Walmart in Bentonville, Arkansas, told Bloomberg. If the trial continues to be successful, Walmart plans to expand blockchain ledgers to multiple foods in the US and China.