Wine costing less than £5 a bottle can have the same effect on the palate as those priced up to six times as much, a psychological taste challenge suggests.
The blind test at the Edinburgh Science Festival saw 578 members of the public correctly identify the "cheap" or "expensive" wines only 50% of the time.
They tasted a range of red and white wines including merlot and chardonnay.
University of Hertfordshire researchers say their findings indicate many people may just be paying for a label.
Two champagnes costing £17.61 and £29.99 were compared, alongside the bottles costing less than £5 and vintages priced between £10 and £30.
The other varieties tasted were shiraz, rioja, claret, pinot grigio and sauvignon blanc.
The participants were asked to say which they thought were cheap and which were expensive.
By the laws of chance, they should have been able to make a correct guess 50% of the time - and that was the exact level of accuracy seen.
The findings demonstrate the volunteers cannot distinguish between wines by taste alone, the organisers of the test say.
Lead researcher psychologist Professor Richard Wiseman said: "These are remarkable results. People were unable to tell expensive from inexpensive wines, and so in these times of financial hardship the message is clear - the inexpensive wines we tested tasted the same as their expensive counterparts."