"There was a party 24,5 years ago in this cottage and there was one tin can of 'surströmming' left over and the host put it under the roof and forgot about it," expert Ruben Madsen told the British radio station.
Ruben Madsen is a member of Sweden's Surströmming Academy. Carefully reaching under the beams of the cottage's roof to bring out the tin, Madsen was wearing an ice hockey-helmet as protection. Given that the fermenting process would have continued over a quarter of a millennium, he was asked if it indeed was explosive.
"Of course there is a pressure, but to say 'explosive' is to promise too much. It can be some kind of leakage and it can be destroyed and that will end up in something that could look liker an explosion," Madsen said.
Asked to describe the smell that came out after the careful opening of the tin, expertly tilted at an angle, Madsen hesitated before saying: "In Sweden we have some rules of what should be told on radio, but it smelled.. to be a little humble I would say: 'rotten eggs'."