Taylor Farms has been confirmed as the supplier of the onions used on McDonald's Quarter Pounders, which are the most probable vehicle of illness in the Escherichia coli outbreak that has sickened dozens of people and caused one death.

As of October 24, 2024, the U.S. Food and Drug Administration (FDA) has reported 75 cases of illness, 22 hospitalizations, and one death caused by the outbreak strain of E. coli O157:H7 in 13 Western/Midwestern U.S. states. Although FDA has not yet confirmed that the slivered onions used on these sandwiches are the definite cause of the outbreak, traceback investigations suggest that these onions, sourced from a single supplier that serves three distribution centers, are the vehicle of illness. The U.S. Department of Agriculture’s Food Safety and Inspection Service (USDA-FSIS) is still investigating the hamburger patties used in the Quarter Pounders to rule out the meat as the source of the outbreak.

Taylor Farms Suspected—and Then Confirmed—to be McDonald's Onion Supplier

At the same time, national food wholesaler U.S. Foods has issued a recall of yellow onions in various forms due to potential E. coli contamination. The recalled onions were sourced from a Taylor Farms facility in Colorado, a third-party supplier to U.S. Foods. The recall of Taylor Farms onions impacts six U.S. Foods distribution centers in the region affected by the McDonald’s outbreak.

The recall did not mention being a supplier to McDonald’s, and according to Good Morning America, U.S. Foods said in a statement to ABC News that it is not a McDonald’s supplier. However, McDonald’s officials also said to ABC News that Taylor Farms is the supplier of slivered onions used in its restaurant locations implicated in the outbreak, but the company is unsure whether the Taylor Farms onions were provided to McDonald’s directly or through an intermediary.

FDA has confirmed that Taylor Farms is the supplier of the slivered onions to the affected McDonald's locations, but at the same time, it is important to recognize that the agency has still not definitively confirmed that the onions used on the Quarter Pounders are the vehicle of illness in the outbreak. The beef patties used on the Quarter Pounders are still being considered by USDA-FSIS as a suspect vehicle of illness.

Taylor Farms has issued a voluntary recall.

National Restaurant Chains Pull Onions Out of Abundance of Caution

The McDonald’s outbreak and supplier speculation has still come with rippling effects across industry. For example, Yum! Brands Inc.—the parent company of several global restaurant chains—has pulled fresh onions from select Taco Bell, Pizza Hut, and KFC locations, out of an “abundance of caution,” it said in a statement to multiple news outlets. Moreover, Burger King revealed that approximately 5 percent of its restaurants source their onions from a Taylor Farms Colorado facility, and that it has proactively asked the affected locations to dispose of the onions. McDonald's itself has temporarily stopped using slivered onions in the states that receive slivered onions from the suspected supplier.

Experts Stress the Importance of Traceability Amid Recall

Food safety experts are stressing that the McDonald's outbreak and the time sensitivity of confirming an implicated ingredient and supplier is a reminder of the importance of solid traceability and adherence to national standards. In a statement to Food Safety Magazine, the National Environmental Health Association (NEHA) said, “Situations like this one are a good reminder about the importance of states adopting the FDA Food Code to protect communities across state lines... This particular outbreak also underscores the importance of the new FDA Food Traceability Final Rule [also known as FSMA 204], which will require recordkeeping beyond existing regulations to be able to rapidly trace and remove potentially contaminated food from the market.”

Update, October 25, 2024: The article has been edited to reflect the most recent information from FDA, including confirmation of Taylor Farms as McDonald's slivered onions supplier and an updated number of illnesses involved in the foodborne illness outbreak.

Update, October 29, 2024: The Colorado Department of Agriculture reported that burger patties from McDonald's Quarter Pounders have tested negative for E. coli. McDonald's has reintroduced Quarter Pounders to its menus.

Update, October 31, 2024: The U.S. Centers for Disease Control and Prevention (CDC) has officially named Taylor Farms onions served at McDonald’s as the source of the outbreak, and has reported 90 illnesses, 27 hospitalizations, two cases of Hemolytic Uremic Syndrome, and one fatality.