On November 21, when the U.S. Centers for Disease Control and Prevention (CDC) published their final update on the 2011 multistate Salmonella outbreak from MealMart-brand “kosher broiled chicken livers,” they found that many of the 179 illnesses resulted from victims consuming undercooked liver.


Speculating further, the agency suggested that the word “broiled” on the label likely led some consumers to think the livers were pre-cooked when they weren’t, possibly leading to unsafe handling or less-than-thorough heating.

The chicken liver outbreak was the latest in a series of food-poisoning outbreaks that have occurred when contaminated foods have combined with misinformation, or misunderstanding. Misunderstandings can arise from a product’s ambiguous labeling or misleading coloration, or from microwave cooking directions that even when followed faithfully, don’t reliably heat food to safe temperatures.

In the last decade, numerous pre-packaged chicken products heated in microwaves have sickened consumers. In most cases, people have either mistaken a raw meat product as pre-cooked, or have tried to follow instructions that ultimately require food to sit for several minutes before being prodded repeatedly with a thermometer.

The problem, however, is that most consumers rarely follow instructions all the way to the thermometer step. According to the International Food Information Council Foundation’s 2011 Food & Health Survey, only 19 percent of respondents even use a thermometer when cooking pre-packaged food.

“Relying on consumers to let the food sit and then take internal temperatures is just not realistic. It’s not going to happen,” said Carlota Medus, Ph.D., epidemiologist for the Minnesota Department of Health. “We can treat consumers as smart people, but the industry should know better than to market a raw product as something that could be microwaveable.”

In 2007, food maker ConAgra recalled its Banquet-brand chicken pot pies in a Salmonella outbreak that sickened 272 people who weren’t able to heat the frozen pies evenly to 165 degrees Fahrenheit.

Two years later, two New York Times reporters found that they could not microwave the frozen pies to safe temperatures — even when heating them for longer than the instructed time and using a more powerful microwave than suggested.

The chicken cubes in the pot pies were pre-cooked, but the vegetables and dough were not. Regardless, Medus said that all products containing raw foods should be very clearly labeled “RAW,” and products containing raw meat should never go to market with microwave instructions.

But consumers also have a responsibility to pay careful attention to the labels, Medus added.

“It all seems like a very simple issue — people didn’t cook their food well enough — but it’s actually a lot more complex than that,” Medus said. “From a consumer perspective, we’re very accustomed to convenience: Heat it in the microwave and serve. We’re so complacent that we don’t even read the labels and just assume we know what to do.”

In 2008, people in 13 states became infected with Salmonella linked to Milford Valley Farms chicken cordon bleu and chicken Kiev. The products contained raw chicken and did not include instructions for microwaving, but were pre-browned and breaded, making them appear pre-cooked to some consumers who then microwaved the products without scrutinizing the label.

Medus cited similar examples in recent years where microwaveable raw chicken products were labeled as “ready to cook” instead of “raw” or “uncooked” — a potentially confusing difference in word-choice. She advises anyone cooking pre-packaged foods to look for signs indicating they’re raw, such as safe handling instructions, a handwashing symbol or phrases like “cook thoroughly.”

Medus co-authored a study in 2008 that examined four Salmonella outbreaks in Minnesota between 1998 and 2006, totaling 67 illnesses. Each outbreak was linked to raw, frozen, stuffed chicken products marketed as microwaveable, including entrees made by Serenade Foods.

Each time, the majority of illnesses arose from inadequate microwaving. Many victims assumed the food was already cooked because of its color or breading, while others simply disregarded the cooking instructions. None of the victims checked the temperature with a thermometer.

After that first outbreak in 1998 and the second in 2005, Serenade Foods and other companies revised their labels and verified their cooking instructions to ensure they could be heated to safe temperatures. Regardless, the two other outbreaks still followed in 2005 and 2006.

“Microwave cooking is not recommended as a preparation method for these types of products, unless they are pre-cooked or irradiated prior to sale,” the study concluded.

According to ABC News, after the 2006 outbreak, Serenade Foods and a few other companies completely removed the microwave instructions from their raw chicken products — a move Medus commended. Approximately 25 companies revised their labels to better indicate that the meat was raw, but many kept the microwave-cooking instructions.

Acknowledging the government’s inability to verify all labels and cooking instructions for pre-packaged foods, Medus said the responsibility lies with food makers to clearly label raw products and thoroughly validate their own instructions. The rest of the burden, she added, falls on consumers.

“We so badly want to buy convenience food that even when it’s not one, it’s marketed as such,” she said. “One issue is the convenience factor, but the other is not looking at the label. There’s too much room for misunderstanding if you don’t read the entire label.”