As an experienced sommelier and brewer, I can tell you that the lifespan of a decanter can vary depending on several factors. One of the most important factors is the air seal of the decanter. A proper air seal is crucial in preserving the taste of the whiskey and ensuring its longevity.
When whiskey is exposed to air, it undergoes a process called oxidation, which can alter its taste profile over time. The tannin and alcohol levels in the whiskey can fluctuate, leading to changes in flavor. However, with a decanter that has a good air seal, you can delay this oxidation process and keep your whiskey tasting good for a longer period.
In my personal experience, I have found that a decanter with a proper air seal can preserve the taste of whiskey for around one to two years. However, it's important to note that this lifespan can vary depending on how often the decanter is opened and exposed to air. If you frequently open the decanter and pour whiskey, the air seal will be broken more frequently, which can accelerate the oxidation process.
It's also worth mentioning that the lifespan of a decanter can be affected by other factors such as the quality of the glass and the cleanliness of the decanter. A decanter made of high-quality glass will be more resistant to wear and tear, ensuring its longevity. Additionally, regular cleaning of the decanter is important to prevent any residue or impurities from affecting the taste of the whiskey.
To summarize, a decanter with a proper air seal can keep your whiskey tasting good for around one to two years. However, factors such as frequency of use, quality of glass, and cleanliness can also impact the lifespan of a decanter. It's important to take these factors into consideration to ensure the longevity of your decanter and the quality of your whiskey.