Hundreds of investors fell foul of fraudsters offering lucrative returns on vintage wine stocks, an expert has revealed.
Jim Budd said the similar ruses have been used with French wines, champagne and whiskey to cheat people.
The investigator said he was regularly contacted by wine lovers with suspicions they may have given cash to criminals.
He was speaking after British police raided the offices of Nouveau World Wines, based in Bromley, south-east London.
Company director Daniel Snelling (34) was among six people questioned over a suspected £3m international fraud.
Mr Budd, who runs www. investdrinks.org, said: "Since 1998, at least 20 wine investment companies have been closed down. Prior to that there were several whiskey companies.
"There have been several variations, Bordeaux sales have been going on since 1998, prior to that it was whiskey and then it moved to champagne for the millennium, warning everyone it was going to run out.
"It plays on the romance and mystique of wine and it is true that if you buy the right wine at the right price at the right time people can make money. Since 2006 prices for top wines have shot up. But these are a small number of wines.
"I get emails from people saying: 'I have spent £100,000 on this company, do you know anything about it?' It is often far too late. I am staggered that people write out cheques for things they know very little about to companies they know even less about. Quite a lot are elderly."