How long have you kept expired food in the fridge? A few days? A week tops? How about decades? Well two Aussies have preserved a McDonald's Quarter Pounder with cheese in its original wrapping for 20 years—and it's showing no signs of rotting or mold. Read More Caviar with gold: The world's most expensive food?



Credit: Casey Dean & Eduard Nitz | "Can This 20 Year Old Burger Get More Likes Than Kanye West?" (Facebook page)

It all started in 1995, when friends Casey Dean and Eduard Nitz went out to grab some food from a McDonald's chain in Adelaide, Australia. One of their friends didn't eat their burger, asking them to "hold on to this for next time." Consequently, Nitz kept it locked away for safekeeping in a wooden box until the pal came back for his meal, which he never did. by simply being kept in the box. Consequently, the burger has dried out with a "rock hard" texture, according to a recent interview with Dean and Nitz for "The Project," a talk show on Network Ten, Australia. What started off as a joke has now turned into a social media phenomenon and a charitable campaign. The two Aussies have now capitalized on this vintage delicacy by setting up website Senior Burger where you can download the official song "Free the Burger" by The Pentagonal Diagonals and buy merchandise. Proceeds from the song and gift sales go to Beyond Blue, a national initiative in Australia to raise awareness on anxiety and depression. Read MoreFancy a year's supply of burgers – for only $144?



Kanye loves a burger