Chobani Mold Sickness: Is Mucor Circinelloides Actually The Culprit?

A popular brand of yogurt is at the center of a recall and investigation after allegedly sickening customers, but the symptoms don't match what scientists know about the contaminating mold.

The Associated Press reported on Sept. 10 that the Food and Drug Administration is investigating reports by 89 people that they felt ill -- with some experiencing nausea and cramping -- after eating Chobani yogurt. Chobani recently issued a recall for some of its yogurts due to contamination with the mold Mucor circinelloides.

Randy Worobo, a professor of Food Science in Cornell University’s College of Agriculture and Life Sciences, explained to HuffPost that it's far too soon to say that yogurt was the cause of these complaints, as this particular kind of mold isn't known to cause food-borne illness.

How the mold first colonized the yogurts is still not clear, according to news reports. However, Worobo noted that while some strains of M. circinelloides grow very slowly at refrigeration temperatures, other strains can grow faster.

Worobo, who was not involved in Chobani's testing of the yogurt and is only commenting in his capacity as a food safety and microbial food spoilage expert, said that in the past, any cases of yogurt being contaminated with this kind of mold has only led to yogurt spoilage, made clear by tell-tale signs like package bloating, a weird smell or a carbonated taste to the yogurt.

What's more, the only instances Worobo knew of in which M. circinelloides actually caused illness, was when immunocompromised people -- particularly people who have recently undergone surgery, catheterization or some other invasive procedure -- were exposed to the fungus non-orally, leading to the skin disorder dermatitis or a pulmonary fungal infection.

However, the mold "doesn't produce a typical toxin that causes what we call a vomiting response," he said.

"As soon as you have nausea and vomiting, that's an indication that it's a food-borne intoxication," Worobo added, explaining that food-borne illness takes place between 24 and 72 hours after consumption.

While Worobo said that based on the information available it's unlikely that this particular mold caused these nausea and cramping symptoms, that's not to say that there is some food-borne pathogen in the yogurt that's not the mold that is causing the symptoms (though Chobani has not reported any instances of this). It's also possible that eating spoiled food can trigger a person's gag reflex, he noted.

"If the food tastes spoiled, sometimes it can make you vomit. but that doesn't make it a pathogen," Worobo said. "Sometimes spoiled foods can cause upset stomachs, and it doesn't necessarily have to be linked to an illness."

He explained that right now, the FDA is likely following up with all the people who reported symptoms after eating Chobani yogurt to learn more about their complaints and what they ate in the hours and days prior to the symptoms. However, if nausea and cramping are the primary symptoms reported by the 89 people, then "it doesn't match what this mold spoilage actually would cause for an illness," Worobo said.