A Utah man who bought a McDonald’s hamburger for presentations on enzymes said the burger is now more than 20 years old — and it appears unchanged.

“David Whipple said he originally bought the hamburger July 7, 1999, at the McDonald’s in Logan, Utah, to use in presentations on enzymes and deterioration. Whipple said the burger ended up forgotten in a coat pocket for several years and it ended up with viral fame when he rediscovered it in 2013. He said the burger was placed in a Big Mac tin and remained there for six years before being taken out again this week. Whipple said the burger still has the same appearance as when he bought it and gives off the smell of cardboard.”

Which means the smell has actually improved in the past 20 years.