I once drank a bottle of some white wine from the central valley, I have no idea what it was, but I had several people taste it in case I was losing my marbles, and it tasted like chocolate. REALLY like chocolate. A white wine. It was not made with any chocolate.
Aromas are just chemicals floating in the air, anyway.
I just read (in a book about scotch) that alcohol can react with a component in European oak to make a chemical that tastes like chocolate. So I'm guessing your white wine was aged for a good while.
Aromas are just chemicals floating in the air, anyway.