The company said it temporarily closed the outlet in Osaka this week, and sent a notice to 95 other restaurants that offer the kind of green tea latte frappe sold to the woman, who said she sustained injuries to her mouth.
Dozens of pieces of plastic were found inside the beverage, a company spokesman told AFP, adding that a plastic instrument used to make the drink may have been the source.
“At this point it is just a hypothesis but we think this plastic tool slipped into a blender to make the frappe,” he added.
McDonald’s Japan unit has been battered by a series of scandals including a human tooth found in some fries.
Last summer, a Chinese supplier was found to be mixing out-of-date meat with fresh produce, sending sales plunging and forcing a rapid switch to a Thai vendor.
In April, the company announced it would renovate 2,000 of its 3,000 Japanese outlets and shut down another 130, while reducing its headcount in a bid to cut costs.
That came after it said in February it had lost a worse-than-expected 21.8 billion yen ($182 million) for 2014 — against a year-earlier profit — recording its first loss in 11 years. – AFP