The logo of Chipotle Mexican Grill is seen at a restaurant in Paris, March 7, 2016Reuters

ChipotleMexican Grillhas retained two leadingfoodsafetyexperts - including acriticof the burrito chain's early response to disease outbreaks last year - as it redoubles its efforts to guard against health scares.


David Acheson, aformerofficial at the U.S.Foodand Drug Administration and the U.S. Department of Agriculture, was brought on as an adviser,Chipotletold Reuters.


The company also confirmed it is working with David Theno, afoodsafetyconsultant andformerJack in the Box executive who is credited with fixingfoodsafetyat the fast-foodchain following a deadly E. coli outbreak in the 1990s.


The two are respected amongfoodsafetyexperts, and their involvement may signal an expansion inChipotle's reforms. But the scope is not yet clear.


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Spokesman Chris Arnold confirmed the consultants were retained last year but would not say when or detail their duties. As recently as early December, Acheson was sharplycritical of the company's initial response to the outbreaks.

In March, the company announced it had hired James Marsden, aformermeat science professor at Kansas State University, as executive director offoodsafety. Arnold said Marsden would have "primary responsibility for ourfoodsafetyprograms."

Expanding its complement offoodsafetyexperts is part ofChipotle's effort to rebound from a spate of disease outbreaks - including E. coli, salmonella and norovirus - last year that crushed sales, repulsed customers and slashed $6 billion off its market valuation.

Chipotle's ability to win back diners is vital to reviving sales and is expected to be a key topic at the company’s annual meeting on Wednesday.

"We have committed to establishingChipotleas an industry leader infoodsafety, and we have assembled an extremely capable team tohelpus achieve that goal," Arnold told Reuters.

Chipotledeclined to make members of the team available for for interviews.

"If I had to put together a dream team to fix something, you could do a lot worse,” said Don Schaffner, afoodscience professor at Rutgers University. But, he added: "I’ve begun to wonder a little bit about too many cooks. Each of those guys is going to have a perspective on what to do to fix the problem."

Michael Doyle, director of the Center forFoodSafetyat the University of Georgia, said he expected the group's focus "would likely be more onfoodsafetypreventive controls and less onfoodtesting."

Chipotle's initial response emphasized testing ingredients for pathogens with the goal of stopping any source of illness from getting into its restaurants. The company touted a testing regime set up by another consultant, Mansour Samadpour, chief executive of IEH Laboratories & Consulting Group.

Achesoncriticized theChipotlefor relying too heavily on that one approach. "I'm not a believer that you can test your way tosafety,” he told Reuters in early December.

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At the time, he said the focus should be on improvingfoodsourcing and handling practices, including how suppliers are approved, “how they are leveraged in terms of training, storing, handling, and preparing offood."

Arnold saidChipotlecontinues to work with the IEH testing firm. Its more recent changes have focused onfoodpreparation. For instance,Chipotlesaid on its latest earnings call that it had started blanching bell peppers in an effort to kill germs.

The chain also has cut some small suppliers. Kenter Canyon Farms said it lost business providing oregano toChipotlethrough a third-party distributor.

“When that whole scandal happened with the E. coli, when they revamped theirfoodsafety. They cut ties with a lot of growers,” said Mark Lopez, sales director for the farm.

Chipotlealso began buying more red onions from Oregon-based River Point Farms, which said it is the country’s largest onion supplier, a source involved in the situation said.

The goal was to make it easier forChipotleto trace the origins of the products, according to the source, who did not want to be identified. River Point declined to comment.

Chipotle's Arnold said the chain would continue to support smaller farms, and has committed to spending $10 million tohelpthem meet its standards. But he said the company has noted that it may be difficult for "some of our smaller suppliers to meet our heightenedfoodsafetystandards."

Big chains - including Yum Brands Inc., the parent of Taco Bell and KFC, and McDonald's Corp - tend to work with a small number of large suppliers, which often have more resources and controls.