The founder of Chipotle is trying to reassure customers that it's safe to eat the food.
In a video posted Wednesday to the Chipotle (CMG) website, Steve Ells says he's made good on his promise to improve food safety protections, including advancements in farming, stricter restaurant inspections and a system that tracks ingredients through the supply system.
Outbreaks of E. coli, norovirus and salmonella sickened hundreds of customers beginning last year.
"We failed to live up to our own food safety standards, and in so doing we let our customers down," Ells says in the video.
The tracking system is meant to ensure that unsafe food can be removed from the Chipotle supply system quickly. The company is also focusing on how food is handled, and implementing "sanitizing protocols."
The problems began in July 2015, when five customers got sick with E. coli after eating at a Chipotle restaurant in Seattle. The following month, 81 people were infected with salmonella from tomatoes at a restaurant in Minnesota. Then, in California, 17 employees got sick with norovirus, which spread to more than 200 people.
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In all, 500 people were sickened, including in other states, before the Centers of Disease Control declared the E. coli outbreak over in February. The company had to shutter dozens of restaurants temporarily.
The Justice Department has opened a criminal investigation, and Chipotle's stock price and sales have been hit hard by the stain on its once-vaunted reputation. Chipotle reported its first quarterly loss earlier this year.
But Chipotle has plowed ahead with plans to expand. The company has set a goal to hire 5,000 people in one day -- Sept. 28 -- and plans to open 200 restaurants this year. Investor Bill Ackman also made a vote of confidence for the company when his hedge fund bought a 9.9% stake.