Early cases of food poisoning came to light in late March – eight patrons of fast food restaurants in New Jersey suffered bloody diarrhea and cramps that rushed them to hospital.
It turns out a bad strain of E. coli bacteria attached to Roman lettuce from the Yuma region of Arizona, causing 210 diseases and five deaths in 36 states before it was out of circulation in late June.
Federal officials struggled to track down dozens of supply lines in 32 states, in a trail of paper that can often be on paper, demonstrating the limitations of tracing food with methods rooted in another century.
Food security advocates and insiders say it may be time to borrow the encryption platform that drives cryptocurrency: blockchain.
"I often describe this as a traceability of food at the speed of thought – as soon as you can think of it, we can know it," said Walmart Food Security Vice President Frank Yiannas, who is adding an IBM-led pilot blockchain which already includes suppliers like Unilever, Nestlé and Danone.
Not long ago, Yiannas, who protects the integrity of food in Walmart's $ 280 billion food empire, would have swept away the notion of a food chain that is immediately "knowable" and verifiable as fantasy . He heard about it two years ago, when Walmart was about to open a food safety institute in China, where 10 years ago a scandal for artificial milk adulteration has sick 54,000 children.
"Until then I only knew it was the technology behind bitcoin," said Yiannas. "I'll tell you I was a little skeptical, just like a lot of people talk about technology."
Blockchain, for all its hood and sword associations, is basically a democratized accounting system made possible by the progress of cryptographic data. Instead of storing proprietary data behind traditional security walls, companies contribute encrypted data blocks to a "distributed" register that can be monitored and verified by each farmer, packer, loader, distributor, wholesaler and product dealer. No one can make a change without anyone knowing and consenting to it.
"If I want to change something or fudge something on my version of the ledger, then I have to share it with everyone else and everyone has to agree with that," Yiannas said. "You can not have two separate groups of books, it's a series of books that everyone sees."
At present, no one can see the whole path from farm to table.
Whenever a food disease breaks out – which tends to happen about 900 times a year – investigators have to go back, one link at a time, from victims to camps, tracing multiple paths between separate companies and sometimes across international borders.
"It is very linear, but the food system as we know is not very linear," said Yiannas.
This linear approach can cost lives and waste billions of dollars on health care costs, lost working hours and trashed food every year, health officials and analysts say. Foodborne illnesses can cost the economy $ 152 billion a year, with contaminated products responsible for a quarter of that damage, according to a study by the Pew Charitable Trust.
Take the mangoes. The increasingly popular fruit grows in small farms scattered throughout Latin America and can house listeria, a bacterium that kills 260 people in the United States each year, according to the Centers for Disease Control and Prevention.
Two years ago, Yiannas told his staff to trace a mango package sliced from a Walmart aisle in the traditional way.
"I looked at my watch and I wrote down the time and date and programmed them," he said. "It took six days, 18 hours and 26 minutes."
Within a week it is considered fast by the current link-by-link method known as "one up, one back" tracking, said Yiannas, who previously directed Walt's Disney World Health and Safety Program. Walmart has a sophisticated tracking system for its part of the supply line.
Beyond the walls of Walmart's distribution centers, however, record keeping can become confusing.
"Believe it or not, it's still widely done on paper," Yianna said. "Many different ways have been done by many different actors."
It took a month to build the blockchain network, which depends on the cooperative partners who agree on what information they need to contribute. At that point, Yiannas felt confident enough to be able to perform the live test at a shareholder meeting last summer.
"It was not staged," he said. "We had a backup in case the technology failed."
It worked: they mapped the mango supply line in 2.2 seconds.
Walmart began to contact suppliers the next day. "I think we're on something here," said Yiannas.
Driscoll berries were among the first companies to join Walmart's pilot blockchain, along with Nestle, Danone, Unilever and others.
Based in Watsonville, Calif. , Driscoll & # 39; s grows berries in nearly two dozen countries, making it the largest berry supplier in the world.
Almost immediately, Driscoll saw much more than food safety in blockchain. A fully compiled ledger might one day draw the grapes on the shelves more quickly, understand which varieties last longer, eliminate waste and even pay suppliers faster, believes the company.
"We want to deepen and continually improve and understand: If we fell flat somewhere, why? Or if we did really well somewhere else, why? And then we constantly refine our operations to be better," said Tim Jackson, vice president of the company for food safety and compliance.
Blockchain, developed in the 1990s, was considered an 'obscure art in the world of cryptocurrency in 2010, when Congress passed the law on modernizing food security, the first major review of food safety regulation deeply fragmented of the nation from the years & # 39; 30.
The law required the FDA to identify high-risk foods and required companies to retain better documentation. The agency has yet to write those rules – and were further postponed by the rollback of the Trump Administration's wholesale regulation
"Seven years after the promulgation of the FSMA, the FDA still has to execute the Congress mandate to create a list of high-risk foods and issue a proposed regulation to improve record keeping, "a coalition of food safety advocates said in a letter to the agency last week.
The groups noted that the leafy greens were responsible for more cases of E. coli disease than any other product – a general category that accounted for half or more of listeria outbreaks, E. coli and salmonella, and a third of the campylobacter outbreaks reported from 2009 to 2013.
Ostroff said that the implementation of the remaining FSMA regulations "would help, but would not necessarily solve the problem" presented by such a large outbreak.
"At every point in the supply chain, you are potentially looking at hundreds and hundreds of records," Many of these documents are archived and available in various ways, from very sophisticated electronic systems … to handwritten records. And they are in different formats. "
Meanwhile, the offensive lettuce has disappeared – consumed, or long ago thrown away after its 21-day deadline, the FDA said. In Yuma no more lettuce is grown, according to the FDA, which has Sources of the Industry Cited
"Although we were hearing about these cases, the product they actually consumed in their home or restaurant was not
Yiannas believes that blockchain could have led investigators to probable culprits long before that the lettuce disappeared.
"Walmart is not chasing the blockchain because it's a new fashion or a shiny coin," said Yianna. "The Rome incident is a perfect example of a real scenario where, if the tools were available, they could be managed a little more effectively."