Oxidized Wine/ Why my wine tastes different?
Oxidization is the process happening when wines are exposed to air. That causes a brownish tint and a distinctive oxidized odor which masks the wine’s aromas. Not only the wines lose their brightness, but also the damage is recognizable in flavor. You can realize the difference if you open a bottle, pour a glass of wine and save the bottle for a week. After that time the wine has developed drier and more characteristics.
Oxidization is the most common of wine faults especially for white wines and older reds. Therefore, you can use wine preservation tools which are effective at reducing air contact with the wine surface, but certainly not if your bottle is oxidized right off the shelf!
There are a number of measures and precautions that can be taken that relate to minimizing air exposure to the must and wine, and sulfite additions that protect against oxidation.To start, transfer wines quickly, especially white wines because they are most prone to the effects of oxidation as they do not have the polyphenols found in reds that act as natural anti-oxidants. Another way to help keep oxygen out whenever you are transferring your wine is blanketing the container you are moving it into with inert gas beforehand. Once the wine is in the barrel or carboy, make sure to top up to limit the air space.
Another consideration is storage. Heat and light speed up the effects of oxidation, so keep your wine in a dark place at cellar temperature (around 55 °F/13 °C).