Here’s a family tradition that you’ll need to discard this holiday season: When baking cookies, cakes, breads or other tasty items, resist the temptation to scrape the bowl and nibble on any leftover raw dough.
And, no, that’s not only because you might get salmonella poisoning from uncooked eggs. For, as the Food and Drug Administration (FDA) warned Tuesday in a Consumer Update, even eggless raw dough can make you sick. Harmful bacteria can be found in dry flour, too.
“Flour is derived from a grain that comes directly from the field and typically is not treated to kill bacteria,” explains Leslie Smoot, a food safety specialist at the FDA, in the Consumer Update. So, if animal waste gets on the field, either from cattle manure used as fertilizer or from deer or other animals, the grain can become contaminated — and remain that way until it ends up in your kitchen.
Complex detective work
The FDA’s updated warning comes on the heels of a report published last week in the New England Journal of Medicine (NEJM) that recounts how health officials doggedly traced a 2015-2016 outbreak of Shiga toxin-producing E. coli (STEC) to a batch of contaminated flour.
In that outbreak, there were 56 confirmed cases of people (aged 1 to 95) who became ill with STEC. Sixteen of those individuals ended up being hospitalized, and one — a teenage girl — experienced kidney failure, although she recovered. No one died.
The symptoms of STEC, which can begin two to eight days after swallowing the bacteria, include abdominal pain, fever, vomiting and diarrhea (often bloody). Most people recover within a week, but the illness can cause a type of kidney failure called hemolytic uremic syndrome, particularly in older adults, children under the age of 5 and individuals with weakened immune systems.
The investigation into the 2015-2016 outbreak, which was a massive effort led by the FDA and the Centers for Disease Control and Prevention, eventually identified flour produced at a General Mills facility in Kansas City, Missouri, as the source of the outbreak. But since FDA inspectors did not find any evidence that the contamination occurred at the facility, they believe the STEC bacteria got into the flour earlier, perhaps in a wheat field before harvest.
“Some farmers use manure from cattle, a reservoir of STEC, to fertilize their wheat fields, which could lead to contamination of the wheat if the cattle are colonized,” the authors of the NEJM report write. “Another source might be white-tailed deer, which are ubiquitous in the United States and are also reservoirs for STEC.”
‘Play dough’ risky, too
Eventually, almost 250 flour-containing products were recalled. But an outbreak could occur again. As a General Mills spokesperson explained to the New York Times, companies cannot heat-treat raw flour before packaging it because doing so “would impact its performance, such as rising properties.”
That means consumers will have to change some of their behaviors in the kitchen, including, as the NEJM report notes, “the consumption of raw or undercooked homemade dough or batter, … as well as allowing children to play with raw dough in restaurants and using flour to make play-dough for children at home.”
Yes, creating holiday ornaments out of homemade “play dough” is also risky. “Even if they’re not munching on the dough, they’re putting their hands in their mouth after handling the dough,” the FDA Consumer Update points out.
How to handle foods safety
Here are the FDA’s tips for safe food handling this holiday season — and throughout the year:
Do not eat any raw cookie dough, cake mix, batter, or any other raw dough or batter product that is supposed to be cooked or baked.
Follow package directions for cooking products containing flour at proper temperatures and for specified times.
Wash hands, work surfaces, and utensils thoroughly after contact with flour and raw dough products.
Keep raw foods separate from other foods while preparing them to prevent any contamination that may be present from spreading. Be aware that flour may spread easily due to its powdery nature.
Follow label directions to chill products containing raw dough promptly after purchase until baked.