The New York Times reports Walmart's Veggie-Tracking B.L.T.: Blockchain Lettuce Technology.
When dozens of people across the country got sick from eating contaminated romaine lettuce this spring, Walmart did what many grocers would do: It cleared every shred off its shelves, just to be safe.
Walmart says it now has a better system for pinpointing which batches of leafy green vegetables might be contaminated. After a two-year pilot project, the retailer announced on Monday that it would be using a blockchain, the type of database technology behind Bitcoin, to keep track of every bag of spinach and head of lettuce.
By this time next year, more than 100 farms that supply Walmart with leafy green vegetables will be required to input detailed information about their food into a blockchain database developed by I.B.M. for Walmart and several other retailers exploring similar moves.