As an expert sommelier and brewer, I have encountered the question of why alcohol cannot be stored in plastic bottles multiple times. The answer lies in the permeability factor. Plastic, although commonly used for packaging various products, is not as impermeable as glass. This means that when alcohol is stored in plastic bottles, there is a higher likelihood of it going off or becoming spoiled compared to when it is stored in glass bottles.
Let's delve deeper into the science behind this. When alcohol is stored, it can undergo various chemical reactions, including oxidation. Oxidation occurs when alcohol comes into contact with oxygen, leading to changes in flavor, aroma, and overall quality. Glass bottles, especially those with airtight seals, provide an excellent barrier against oxygen. They are impermeable to both oxygen and carbon dioxide, which helps preserve the alcohol's integrity and prevent spoilage.
On the other hand, plastic bottles, although convenient and lightweight, are not as effective in preventing oxygen from permeating through. Plastic is more porous, allowing small amounts of oxygen to seep into the bottle over time. This can accelerate the oxidation process and negatively impact the taste and aroma of the stored alcohol. Additionally, plastic bottles may also allow carbon dioxide to escape, leading to a loss of effervescence in carbonated beverages.
I have personally experienced the effects of storing alcohol in plastic bottles. A while ago, I had a batch of homemade fruit-infused vodka that I decided to store in plastic containers. After a few weeks, I noticed a distinct change in flavor and aroma. The vodka had developed a slightly sour taste and lost some of its fruity essence. This was a clear indication of oxidation, which could have been avoided if I had opted for glass bottles instead.
It is important to note that not all plastics are created equal in terms of permeability. Some plastics, such as PET (polyethylene terephthalate), are relatively more impermeable and commonly used for beverage packaging. However, even with these plastics, the level of permeability is still higher compared to glass.
To summarize, alcohol should not be stored in plastic bottles due to their higher permeability to oxygen and carbon dioxide. Glass bottles, being impermeable to these gases, provide a better environment for preserving the quality and freshness of the alcohol. So, if you want to ensure the longevity and taste of your spirits, opting for glass bottles is the way to go.