There's been plenty of blood so far, but not enough wine for my liking.
The Witcher 3: Blood and Wine - Wine is Sacred
Our first objective is a chat with the duchess. Travel to Beauclair Palace and follow your HorsePS up the stairs for a chat.
After the cutscenes you’ll have to travel with the duchess and Damien to a vineyard, Along the way you’ll have to battle some panthers. Stick very closely to the NPCs at all times or they’ll be annoyed with you at the other end.
When the cutscenes end take a moment to check out a nearby notice board if it is marked in yellow, to collect the secondary quest A Knight’s Tales (recommended level 40) if you don’t have it already. There’s also a herbalist here (who plays a mean Nilfgaard deck) but you need to stick to the duchess so follow her down into the cellar and check the ledger on the desk.
There’s a variety of minor loot in the room. To save time, grab it all now – you’ll need the tap and hammer among the junk a little later. Your goal is the sign on the upper level at the south end of the walkway. Assuming you have the tap and hammer in hand you can then immediately proceed to open the barrels until you find the bad one; it was the second from the left as you face the barrels for me.
After the cutscenes you’ll have to battle some bandits. Be careful with Igni here as there are exploding barrels around. The bandits are level 42 but if you’re not up to scratch just keep your distance and take them one at a time while the guard keeps them occupied. Whenever a bandit turns to face a guard, hit ‘em from behind.
After the conversation you can choose to go with the ducal party or meet them at your next objective. Say you’ll meet them there if you want a break to go do some side questing – or just to collect all the junk loot dropped by the bandits.
However you get there your next goal is in Beauclair Port. Have a chat with the duchess and Damien to end this quest and begin The Man from Cintra.