EXCLUSIVE: Utah man unveils 20-year-old McDonald's hamburger

20-year-old McDonald's hamburger. (Photo: Adam Forgie, KUTV)

(UPDATE 1/6/20 12:26 p.m.) -- In response to this story, Barbara Schmiett with McDonald's Utah issued this statement to 2News:

In the right environment, our burgers, like most other foods, could decompose. As the story alludes to — in order to decompose, you need certain conditions — specifically moisture. Without sufficient moisture - either in the food itself or the environment - bacteria and mold may not grow and therefore, decomposition is unlikely. So if food is or becomes dry enough, it is unlikely to grow mold or bacteria or decompose. Food prepared at home that is left to dehydrate could see similar results. Similarly, this particular burger is likely dried out and dehydrated, and by no means the same as the day it was purchased. The reality is our burgers are made with 100% USDA inspected beef. There are no preservatives or fillers in our patties and the only thing every added is a touch of salt and pepper on the grill.

HEBER CITY, Utah (KUTV) -- David Whipple is the owner of what he calls "the world's oldest hamburger" -- a 20-year-old McDonald's hamburger, which will be of drinking age this July. What makes the burger remarkable is that it looks like it's only a day or two old. Watch as 2News was there when David took his burger out of its Big Mac tin for the first time in six years:

The tale of David's zombie-burger began at a McDonald's restaurant in Logan, Utah on July 7, 1999 -- back when Bill Clinton was president.

That's when David bought his famous burger -- a story we first brought to you in 2013 in a now-viral YouTube video.

David purchased the burger to use in presentations he was giving about enzymes and how things deteriorate.

David said:

It got stuck in a coat pocket. The coat got thrown in the back of my van, and I guess it just got hung up on our closet in Logan. Subsequently we moved from Logan to St. George, Utah, and it stayed there for a couple years and I think my wife was giving the coat away or something and found it.

After talking with 2News about the burger, David put it back in its tin -- until we decided to find out if the burger was still around as it turned 20.

Sure enough -- the burger looked the same and didn't smell like much other than cardboard.

Watch David's full story in the video above.

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