This clip appears to be a user-made soundboard combination rather than a sound taken from a film, television show or viral video, and no documented origin explains the Mercadona connection. That ambiguity is typical of short meme audio, where a familiar everyday brand is paired with an absurd bodily sound purely for comic contrast. Online, clips like this circulate through soundboards, short-form videos and group chats, where they are reused because they are instantly understood without context. The supermarket reference makes the joke feel local, while the fart keeps it universally crude and easy to reuse in silly edits.