About 7 days ago, I tried a bottle of white wine from the " Jurancon" region...

[joe r]

...of France. When I first tasted it it was screeching acidic and hard to drink. Just 1/2 hour ago I tried the same opened bottle of wine again, and this time it had developed into a more drinkable and complex wine, with pleasant notes of sawdust and nutmeg in its long finish. I know that you are supposed to make a wine "breathe" a little before drinking it (I did leave the wine in the glass for 15 minutes the first time I tried it), but one week? What happened?