As an experienced sommelier and brewer, I can confidently say that pouring whisky into cheap plastic bottles is not ideal. Whisky is a delicate spirit that can be easily affected by its container, and plastic bottles can have a negative impact on its quality.
Firstly, plastic is not completely impermeable, meaning that it can allow small amounts of air to interact with the whisky over time. This can lead to oxidation, which can alter the flavor profile and overall character of the whisky. Additionally, some plastics can release certain chemicals into the liquid, which can further affect the taste and aroma.
To preserve the integrity of your whisky, it is best to use clean, glass sample bottles for storage. Glass is non-reactive and provides a better barrier against air and potential contaminants. This will help to maintain the original flavors and aromas of the whisky for a longer period.
Furthermore, it is important to keep in mind that once a bottle of whisky is opened, its exposure to air accelerates the oxidation process. This means that the whisky's flavors can change and diminish over time. While some whiskies may still be enjoyable even after prolonged exposure to air, others may lose their complexity and become dull.
To ensure the best drinking experience, it is recommended to finish opened bottles of whisky within a year, or at least within a reasonable timeframe. If you find yourself with a partially filled bottle that has been open for an extended period, it is advisable to transfer the remaining whisky into a smaller, clean, glass bottle to minimize the air contact.
In my personal experience, I have encountered instances where whisky stored in plastic bottles for an extended period tasted noticeably different compared to the same whisky stored in glass bottles. The plastic bottle sample had lost some of its original flavors and had a slightly off-putting plastic-like note. This reaffirmed my belief that glass is the superior choice for whisky storage.
It is not recommended to store whisky in cheap plastic bottles due to the potential for oxidation and the release of unwanted chemicals. Glass sample bottles provide a better barrier against air and contaminants, helping to preserve the original flavors and aromas of the whisky. Remember to finish opened bottles within a year or transfer the remaining whisky into clean, glass bottles to maintain the best quality.