The vintage wine in Qud is made from the ripe and luscious urberry.
Sold by vintners in The Six Day Stilt, but can sometimes be found in stock on other merchants. Wine is very valuable, selling for around $110 at a modest 18 ego for a full waterskin. If you can find a pool of wine in a fungi infested area it's possible to fill up and purchase many waterskins for more liquid capacity. Use the Joppa Recoiler to carry more weight than you would normally be able to walk with and equip any ego boosting equipment to get more value out of each trip.
If you drink too much wine, your character gets confused. Which is just the games way of saying that you got drunk. It doesn't have much other practical use other than to celebrate after a hard fight or two, so generally it should be traded for equipment and fresh water.
It can be one of the required ingredients for putrescence.