Glass expert Andy McConnell tasted the liquid in a bottle and concluded it was either a vintage port or a red wine.
The Antiques Roadshow star was in for a shock during an episode of the BBC show in Trelissick, Cornwall, after a local found a mysterious bottle buried in the threshold of their house.
The excited specialist used a syringe to extract the contents and move it into a glass while remarking "it's very brown" before using his finger to have a taste.
He grimaced before he told the audience: "I think it's port - port or red wine... or it's full of rusty old nails and that's rust!"
The show aired in 2016 and host Fiona Bruce later confirmed the antique contents in a recording broadcast in 2019 after scientists at Loughborough University used an x-ray to check what was inside the bottle.
What Andy thought was a 150-year-old bottle of port was stunned to discover it was actually full of urine, several brass pins and one human hair.
She said: "Inside were these brass pins, all of these dating from the late 1840s and the liquid - urine, a tiny bit of alcohol and one human hair."
Fiona then explained the object was a witches' bottle - which had been buried by the front door of the house to guard against evil spirits.
She continued: "So what this was not a bottle of port or wine but a witches’ bottle.
"So buried in the threshold of the house as a talisman against witchcraft, against curses, against misfortune coming into the home."
Fiona added: "So you glad you tried it?"
Andy replied: "It was too much of a good opportunity to miss!"
Antiques Roadshow airs Sunday on BBC One at 8pm
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