Wine has been faked, diluted and adulterated for profit since it was invented. The Roman naturalist Pliny the Elder (AD 23-79), killed during the eruption of Vesuvius that destroyed Pompeii and Herculaneum, was convinced that the names of different wines were vacuous and the vintages as untrustworthy as the producers.

Of course, by definition, wine fraud is impossible to estimate accurately, but the consensus among experts is that it is widespread at both ends of the market. The big money, of course, is at the upper end, in the investment market. Stories of large-scale fraud in China’s emerging wine market are legion.

But even the major supermarkets are not immune. Tesco, for instance, found itself red-faced in 2010 when it sold cut-price Louis Jadot Pouilly-Fuissé – reduced from £14.99 to £5 – that turned out to be indifferent hock not worth a fraction of even the reduced price. All the more embarrassing that the discovery was made by a vigilant customer rather than their own wine buyers.