However, a food safety expert said the mold that caused the yogurt to spoil before its expiration date does not cause foodborne illnesses. That means either Chobani hasn't yet identified or publicized everything that caused the yogurt to spoil, or consumers must have eaten something else to cause them to vomit or have diarrhea, said Randy Worobo, a professor of food science at Cornell University.

"I'm not discounting the consumers, that they didn't get sick, but it's more than likely not the mold that made you sick," he said in an interview Monday. "The species they say are involved, it hasn't been linked to previous food-borne illness outbreaks. It's generally regarded as a spoilage organism."

Chobani quietly started asking retail stores to pull some of its yogurt off the shelves in the days before Labor Day weekend after numerous people complained on Chobani's Facebook page about bulging and swelling containers and yogurt that went bad before its expiration date. The company first took down the comments but eventually initiated a voluntary recall Sept. 4.

Tamara Ward, speaking for the FDA, said the agency is evaluating the adequacy of Chobani's recall. She said the agency has received 89 complaints about ill health effects from consumers.

"The various issues reported included cramps, nausea, headache and diarrhea following consumption of the recalled yogurt," she wrote in an email to the Public Investigator.

Chobani assured customers last week that the mold doesn't pose a health risk. Still, Emily, a mom from Caledonia who didn't want her last name used, said she believes her 1-year-old son, Harrison, got sick from eating it. She said that before Chobani issued a recall she fed Harrison yogurt from Champion's "Rockin' blueberry" tubes.

"I fed one to my son at dinner, and that night, he woke up vomiting a few times, and then had extremely bad, foul diarrhea," she wrote in an email Monday. "Each day I thought he was getting better, so I would give him more yogurt thinking that would be soothing for his upset stomach (I thought he had a stomach flu) and then suddenly he would get sick again and the pattern would repeat."

She said Harrison would cry from stomach cramping right before getting sick. That went on from Saturday through Wednesday of last week, when she stopped giving him the yogurt, she said.

"I never thought it was the yogurt until I heard about the recall, and then looked at the partially empty box in my fridge, and it is the exact type that was listed as recalled on the FDA website," she said. "I did contact Chobani yesterday, but have not yet heard back."

Neither has the Public Investigator, who contacted Chobani on Monday to get a response.

Worobo is not affiliated with Chobani but was used as an expert in Chobani's release about the mold. He said many consumers have emailed him since then, saying they fell ill right after eating the yogurt. But symptoms don't occur within hours of eating something bad unless the culprit is disease-causing microorganis, such as staphylococcus and salmonella, he said.

"With this mold, if you were to ingest it, you would not get vomiting or diarrhea within hours of consuming it," he explained. "A lot of the emails I've had, they said they fed it to their child or themselves and within an hour, they had nausea or vomiting or diarrhea. That's only with pre-formed toxins, when you had microorganisms that produce that vomiting or diarrhea toxins. This mold doesn't have that diarrhea toxins."

The kinds of bacteria that do carry toxins can't grow in environments as acidic as the yogurt, he said. The mucor circinelloides mold that an independent lab identified in the Chobani case is common in a dairy environment and on fruits and vegetables.

Many readers told the Journal Sentinel they threw their Chobani yogurt out because it tasted tart and was tingly on their tongues, or because it exploded in their fridges or lunch packs.

A Chobani spokeswoman said last week that there was no mold when the yogurt left the Idaho plant. But Worobo pointed out the mold is difficult to detect. It only takes one mold spore so tiny that it can only be seen in a microscope to spoil the yogurt. If the contamination level of the yogurt was low, the company may not have discovered the mold during sampling, he said.

"When they get tested for what's in there, microbiologically speaking, it can be below the detectable limits," he explained. "You can have one spore in a container but the lab only analyzes 10 grams. If you're not lucky to get that spore in that 10 grams, it's going to show up that it's clean."

The fact that mold doesn't show up out of nowhere, but originates with a spore before the yogurt was vacuum packed, indicates that it was an issue at the plant, he said.

The mold was present in both plain and flavored yogurt, which indicates it wasn't an issue with spoiled fruit or berries. It was likely a matter of Chobani not properly sanitizing part of its plant, for instance the fillers that fill the containers, he said.

"Usually with mold contamination, they missed a spot where they didn't properly clean and sanitize," Worobo said.

The recalled products had expiration dates that spanned about four weeks, from Sept. 11 through Oct. 7. Ward said the FDA is "in discussion" with Chobani about its quality controls and food safety checks.

Consumers who believe they have foodborne illness as a result of the recalled yogurt should contact their health care provider and can report their illness to Chobani at (877) 847-6181 and the FDA at (800) FDA-1088 or (800) 332-1088.