McDonald's supplier recalls onions and tells a burrito chain to stop using the ingredient

• McDonald's supplier Taylor Farms recalled some yellow onions due to potential E. coli contamination.
• Another restaurant received a notice about the recall on Wednesday, according to the Colorado Sun.
• McDonald's has pointed to onions as a likely source for a deadly E. coli outbreak this week.

A major McDonald's supplier is reportedly recalling some of its yellow onions as the fast-food chain deals with a deadly E. coli outbreak.

Taylor Farms told Bloomberg late Wednesday that it hasn't found E. coli in its onions yet but is acting "out of an abundance of caution." The onions in question came from Taylor Farms operations in Colorado, according to the report. Taylor Farms did not immediately respond to a request for comment from Business Insider.

Food distributor US Foods sent a notice this week to Illegal Pete's, a burrito chain with restaurants in Arizona and Colorado, saying that Taylor Farms was conducting the recall "due to potential E.coli contamination." The letter, which was obtained by the Colorado Sun , told customers with certain batches of Taylor Farms onions to destroy them.

The recall comes as McDonald's grapples with an E. coli outbreak that the Centers for Disease Control and Prevention said Tuesday was connected to some of the chain's Quarter Pounder burgers.

At least 49 people have fallen ill and one person has died in connection with the outbreak, according to the CDC . Most of the cases involve people in the Western US, especially in Colorado, the CDC said.

McDonald's executives said during a press call on Wednesday that they had identified onions as a likely source of the E. coli contamination, though they added that they had not ruled out beef patties as a source either. All potential sources of the contamination have been recalled from McDonald's stores, the executives said.

McDonald's did not respond to a question from BI during the call about whether other restaurants relied on the same supplier for onions.

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