CINCINNATI -- The U.S. Food and Drug Administration says it is investigating popular yogurt maker Chobani's handling of a mold problem, Reuters reports.
Chobani pulled some of its Greek yogurt from supermarket shelves this week after hearing of "swelling or bloating" in cups.
Thousands of customers took to social media to complain about "off-tasting" yogurt with bloated containers. Others deplored the characteristically thick Greek yogurt's "runny" consistency.
But the company never issued a recall notice over the problem, the FDA told Reuters. Instead, it contacted stores directly.
Chobani said it has investigated and found a type of mold commonly found in dairy that may be to blame.
The company said the affected product came from its Idaho facility and represents less than 5 percent of its total production. Chobani has been working with retailers to remove and replace containers with the code 16-012 and expiration dates Sept. 11 to Oct. 7.
"Over the past few days, with the help of our retail partners, we proactively withdrew product from store shelves and I decided to voluntarily recall the limited amount of remaining product to be extra careful and cautious," Ulukaya wrote. "My heartfelt apologies to our friends, fans and consumers who were impacted, as your loyalty and safety is something we cherish and never take for granted. We have worked round the clock to fully fix the issue and have been shipping fresh product to stores."
Chobani did not say the total number of its cups or what varieties were affected. The effort was voluntary and it is not issuing a formal recall.
A representative for Kroger told the Associated Press that Chobani issued the product withdrawal Friday.
"It was not a food safety issue," Kroger spokesman Keith Dailey said in an email to the Associated Press.
Chobani, which said it uses only high-quality, natural ingredients, has grown rapidly since it was founded in 2005, AP reports.
The private company had an estimated $244 million in revenue in 2010, according to S&P Capital IQ.
Chobani says customers with the affected code dates can contact its customer service team at email@example.com to get replacement products.
The Associated Press contributed to this report.