The viral TikTok has been viewed more than 3.9 million times.
A McDonald's meal that's older than most of the users on the viral video app has intrigued and horrified TikTok users after emerging from its weathered bag in pristine condition.
The video was posted by TikTok creator aly.sherb under the hashtag #grandparentsoftiktok.
A woman believed to be her grandmother begins the video holding a shoebox up to the camera, on which she has handwritten "hamburger".
"You want to see my hamburger? It lives in a box in the cupboard," she said.
When she opens the shoebox viewers are treated to a wrinkled old McDonald's bag advertising a Nascar race from 1996.
The woman then begins pulling out different parts of what was once a meal.
"The french fries look like they might have fallen under your seat around a month ago, they've never rotted or decayed," she said.
"The hamburger itself: the bread has never moulded, the meat has never rotted," she adds, though the hamburger appears to be devoid of any sauce, onions or pickles that may have once been included.
"So, that's the 24-year-old hamburger. Not sure what would happen if you ate it though."
Aly responded to commenters to explain that her grandma is a science teacher and had kept the meal as an experiment.
The viral TikTok has been viewed more than 3.9 million times.
It's the latest in a long run of archaeological studies into the preservation of McDonald's meals.
Morgan Spurlock explored the idea in his anti-Maccas doco Super Size Me.
There is also a meal from the last McDonald's in Iceland that has been kept under glass since the restaurant chain left the country in 2009.
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