He waited for a hush among his audience, ensuring all eyes were on him. Then he seized a full bottle of white wine and drained the contents in one, smashing it triumphantly on the ground as the restaurant clapped approvingly. "He can do that again in 10 minutes' time," said our friend. "Just give him a moment to rest."
It was Sunday night in a small eating house near the port of Poti, a ragged seaside town on the eastern edge of the Black Sea. What, one wondered, would happen if someone tried that in a French cave with a bottle of Chablis?But Georgia is different. Drinking feats are as old as wine itself - which is no small vaunt, as the country claims to have invented the stuff. Stone jars and wine presses have been found in this part of the Caucasus which date from 2000BC.
History has not bred the same snobbism about viniculture here as it has elsewhere, even though Georgian wine, helped by foreign partnerships, has begun to win fans abroad.
Even if the Georgians had once felt so inclined, any finesse would probably never have survived the Soviet era, when the family farmers were herded into collectives and told to churn out as much wine as possible, never mind the taste. There is, however, a rich drinking folk lore, tales of heroic endurance and excess which are told and retold among this nation of five million.
The chief character in these exploits is the Georgian tamada, or toastmaster who oversees all feasts, from weddings to funerals. Toasting in Georgia is a serious business and top tamadas are regarded with the same awe as accomplished wrestlers. Myths abound. One is rumoured to be able to eat an entire turkey. Another is said to have drunk a bucket of wine. Apocryphal these yarns may be, but there's no denying that a tamada must be unusually robust.
Although Georgian weddings can last from lunch until dawn, he cannot leave the table - not even to dash to the lavatory - as this signifies that the party is over. There are numerous toasts: to parents, women, the hosts, the future, the dead. Glasses - or, sometimes, drinking horns - are often drained to the bottom and the wine, considered by Georgians to be the drink of God, never runs out, not least because every other household makes their own in stone jars. Careful pre-match preparation is therefore essential.
"Some tamadas eat butter beforehand," said Zaal Kakhiani, 70, a surgeon. A dapper and lean man, with a mischievous grin, he has been a tamada for at least three decades, although he fears he is not what he was. "These days I cannot drink more than three litres of wine. I used to drink eight. I could drink because I was tense.
"There are five or six serious tamadas in the whole of the country. There are, of course, a lot of pretenders. But the good ones can drink and still speak well. The others only think of getting everyone drunk as soon as possible." And how does he manage without a pee? It's the adrenalin, he explains; you hardly think about it.
There is an element of bravado in all this, though the clay wine tumblers on sale at the roadside are testimony to the bacchanalian mood of Georgia - they are round-bottomed and cannot be put down.
This has even percolated into way they insult one another. Driving along the Black Sea coast, we were whistled down by three portly policemen sitting under a tree. Asked why they had pulled us in, they said that they did not like how we had stopped - after they had flagged us down. They wanted two bottles of champagne to ease their outrage.
"You know what we Georgians do to people like that?" said our driver, Aftandel, after arguing his way out of the penalty. "We walk up to them with a glass of beer, and we toast them to their faces." In this wine drinker's Mecca, a toast in beer is a slap in the face.