Can you lose something if wine is decanted too long before consuming?
Answer: In two words, it depends. There are two fundamental reasons to decant a wine:
1. To provide extra aeration for a recent vintage by exposing it to the air as it is poured from the bottle into a decanter.
2. To separate the sediment or deposit of tartrate crystals that has accumulated at the bottom of an older bottle. Generally, wine over five years old might start showing some sediment. Be sure you haven’t shaken the bottle prior to decanting or it won’t be successful. I like to leave a bottle with sediment set upright for 24 hours prior to decanting. This will insure all the sediment is at the bottom of the bottle and you can control it during the process. The former poses little risk or damage to a wine, and may aid in “opening up” its contents. Some wine collectors open and decant a recent vintage several hours prior to serving to facilitate the process. While the latter may succeed in eliminating the sediment (you stop pouring when the deposit reaches the neck of the bottle), you also expose the wine to oxygenation in the process, which poses a risk.
Please understand that decanting wine is not just for reds. White wines can improve its taste by decanting as well. When in a restaurant don’t be intimidated by the sommelier. Ask if you can have your white wine decanted. There is no charge to decant and almost always it improves the wine by this procedure. It’s the length of time between decanting and consuming the wine that can be a problem.