Food safety: Why are chicken nuggets and other poultry products recalled?

A spate of chicken-related recalls since the start of the year can be blamed on human error and faulty equipment, food-safety experts say, but at least one, involving wood possibly in the food, remains a mystery.

Food companies have issued eight voluntary recalls in the first six weeks of the year, according to the  Department of Agriculture's Food Safety and Inspection Service (FSIS) website. The recalls are a result of allergens not listed on the packaging, and wood and rubber that made their way into the chicken. 

Food-safety experts say that undeclared allergens may get into food when food manufacturers' suppliers change their ingredients and don't tell the food makers. Another possibility is that the food the plants are producing is the same, but someone in the factory loads rolls of incorrect labels into the packaging machines.

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"Typically, when it's undeclared allergens, it does mean they didn’t follow the recipe or something went in the wrong box," said University of Florida food-safety expert Keith Schneider. "Typically, when something goes wrong, it’s human error."

How material like rubber, plastic or metal get into food is a bit easier to trace. A worn or broken-off piece of the equipment, like a gasket, a chopping blade, a conveyor belt or the impeller that pushes products down the line could be to blame. And usually, it's a maintenance or cleaning crew who noticed that a small bit is gone. Metal is generally found by a factory's metal detectors, though.

"Now, you’re doing chicken CSI," Schneider said. "You’re missing a piece. Where's that piece? It has to be in the product."

In a country with an insatiable love for chicken, these recalls are big news. U.S. retail sales of chicken totaled $21.1 billion last year, up 10.5 percent from $19.1 billion in 2013, according to the global market research firm Mintel. Ninety-six percent of Americans eat chicken, and more than half do so a few times a week.

"I'm a chicken eater, and now I have to be hyper-vigilant," said Allison Lambert, 36, a personal trainer and nutrition coach in Portland, Oregon, who eats chicken four times a week. "These recalls are very distressing to me because I don't know what's safe to eat." 

Here are the chicken recalls since the start of the new year, starting with the most recent: 

• Undeclared eggs – VICS Acquisition's happi foodi Bloody Mary Inspired Chicken, Southeast Grocers Marsala Chicken and Southeast Grocers Mediterranean Herb Chicken  
• Undeclared wheat – Taylor Farms H-E-B Meal Simple Chile Relleno
• Possibly containing rubber  –  Pilgrim’s Pride Uncooked Popcorn Style Chicken Breast Chunk Fritters with Rib Meat
• Possibly containing rubber  – Tyson White Meat Panko Chicken Nuggets
• Undeclared milk – Perdue Fun Shapes Chicken Breast Nuggets
• Undeclared milk –  Harvest Food Group's yumnum global cuisine Yakitori Seasoned Chicken Fried Rice
• Undeclared coconut –  Custom Made Meals Red Chili Orange Chicken Skewers
• Possibly containing wood – Perdue SimplySmart Organics Gluten Free Chicken Nuggets Gluten Free 

That's five undeclared allergen recalls, compared with 15 in all of 2018, and three extraneous-material recalls versus four in total last year, according to FSIS data. In 2017, the tallies were 24 and nine, respectively.

Pilgrim's said the recall is the result of an undetected failure of a food-grade rubber gasket, while Tyson pointed to the rubber part of an equipment seal that was pinched. Both explained that they've put measures in place to prevent these kinds of incidents from happening again.

Perdue said it doesn't conclusively know how wood wound up in its nuggets, but the company is eliminating wooden pallets, the only wood present on the manufacturing floor near the unpackaged product. Its undeclared-allergen recall was the result of putting the wrong label on the back of packages. The company has since conducted label verification training at its factories to make sure all protocols are followed.

When asked how the problem that caused each of their recalls occurred, Taylor, happi foodi and yumnum didn't answer.

Custom Made Meals and VICS declined to comment. And Southeast Grocers didn't respond to e-mails and phone calls.

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"They’re quality-control issues," said Seattle-based food-safety lawyer Bill Marler. "When we process that much and it’s so industrialized, one little mistake will be noticed quickly."

In all the 2019 chicken-related recalls so far, the foods have been processed, like nuggets and dishes with sauces. None were whole chickens or raw cut pieces.

"The more processing steps a product goes through before it gets to the consumer, more opportunities for adulteration come into play, whether it's foreign material or some kind of other bacterial contamination," said FSIS administrator Carmen Rottenberg.

FSIS officials said these types of recalls aren't specific to the poultry industry and that for the last couple of years, they've made a big push to inform companies about how to handle customer complaints and recalls.

Jim Dickson, a professor of animal science at Iowa State University, said because of Americans' increased focus on food safety now due to more allergy awareness and the plethora of information easily available online, they're staying on top of food recall notices more.

"In general, people are paying closer to attention to their food," Dickson said. "In the past, a consumer might have come across a piece of plastic in their food and would've maybe sent to a note to the manufacturer. … They would've got sent a couple of coupons. Now, they’re calling on state health departments and the USDA."

That watchfulness is what keeps Lambert, the fitness and nutrition professional, on her toes. She said she keeps track of recalls not just for herself, but also for her clients

"Is this going to be a continual problem?" Lambert said. "I just honestly hope for the best. You never know until you get sick."

Follow USA TODAY reporter Zlati Meyer on Twitter: @ZlatiMeyer