TikTok user Aly Sherb’s grandmother is getting a lot of attention for holding onto a McDonald’s hamburger meal she reportedly bought in 1996.

In the video Sherb posted last week, her grandmother held up a white shoebox with the word “hamburger” written on it.

“So you wanna see my hamburger that lives in a box in my closet,” she told her granddaughter, then lifted the lid to reveal a brown McDonald’s bag.

“This is the sack that it came in, and it was advertising a NASCAR race in 1996, so this dates the hamburger and its sack to 24-years-old now,” she explained.

Underneath the bag was a small order of fries, perfectly preserved.

“The french fries look like they maybe could’ve fallen under your seat a month or so ago. They’ve never rotted or decayed,” she commented.

Next, she pulled the hamburger, wrapped in McDonald’s paper, out of the bag and held it up to the camera.

“The hamburger itself, the bread has never molded. The meat has never rotted. It’s never even broken. Its completely intact,” Sherb’s grandmother said while taking the bun apart.

In 2014, the University of Guelph’s Department of Food Science and Quality Assurance Program Director Dr. Keith Warriner offered an explanation as to why McDonald’s meals did not rot after long periods of time.

Warriner said the foods would, in fact, rot if kept in certain conditions:

Essentially, the microbes that cause rotting are a lot like ourselves, in that they need water, nutrients, warmth and time to grow. If we take one or more of these elements away, then microbes cannot grow or spoil food.

In the example of a McDonald’s hamburger, the patty loses water in the form of steam during the cooking process. The bun, of course, is made out of bread. Toasting it reduces the amount of moisture. This means that after preparation, the hamburger is fairly dry. When left out open in the room, there is further water loss as the humidity within most buildings is around 40%. So in the absence of moisture or high humidity, the hamburger simply dries out, rather than rot.

The video of Sherb’s grandmother and her burger was viewed over three million times as of Sunday, according to Fox News.

“So, 24-year-old hamburger. Not sure what would happen if you ate it, though,” she concluded.