McDonald's proved it hadn't served up any leaping lizards, after preliminary lab tests laid to rest the reptile ruckus that erupted when a customer claimed to have found a baby lizard in her chicken sausage McMuffin.
"The sample collected is 100 percent chicken," Kevin Lim, the burger maker's senior communications manager for Singapore said in an emailed statement.
"Sandy Sand" posted a photo of a half-eaten sandwich on McDonald's Facebook page, with what appeared to be a tail sticking out, although it's difficult to discern detail. Sand alleged the rest of the lizard was contained within the sausage patty.
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But McDonald's Singapore said the "tail" was actually a chicken blood vein, which was white because the Halal slaughtering process drains away all blood. (McDonald's branches in Singapore are Halal, in line with Muslim dietary requirements.)
"We have also traced back the product's production process, and no product from the same batch had any quality issues reported," Lim added.
Sand's posts on Facebook attracted multiple comments. Her original photo and post remains on McDonald's page, but are now buried beneath other comments, including complaints about the cost of milkshakes.
"It's not really our policy to delete comments from our [Facebook] page," Lim said, before the lab results were released. "We have a moderation policy."
Some of the Facebook commentary descended into inexplicable anti-foreigner sentiment, but most comments simply urged patience while McDonald's ran tests.
"Thanks to McDonald's for their attention, and sending their personnel over at this hour to collect it for analysis," Sand wrote.
Other comments on Facebook were more tongue-in-cheek. "Dear McDonald's, can (you) make egg McMuffin with baby lizard recipe or not? Give us reptile taste," one said.
After one commentator alleged Sand was merely seeking compensation, and urged McDonald's to sue her, Sand responded: "I just want public awareness, and (for) McDonald's to answer for the unhygienic food, and also to urge them to investigate the factory supplying them with sausage patties."
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The lizard debacle is far from the first time a fast-food chain has faced bad publicity, after patrons claimed to have found foreign objects in food. Last year, a Michigan branch of Arby's served part of an employee's finger in a roast beef sandwich, after an employee maimed her finger with a slicer and then left without telling co-workers.
In 2005, Anna Ayala was found to have planted a surgically amputated human finger in a bowl of Wendy's chili. Ayala, who had history of launching lawsuits, had purchased the finger from a friend of her husband.
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter@LeslieShaffer1