As an expert sommelier and brewer, I can confidently say that unopened hard cider does not necessarily need to be refrigerated. However, it is important to note that cider is a perishable product and its flavor is best enjoyed when it is fresh. While refrigeration is not a requirement, it can certainly help increase the longevity of the cider's quality and flavor.
When cider is stored in a cool environment, such as a refrigerator, it slows down the aging process and preserves the freshness of the product. This is especially important for ciders that are made without the addition of preservatives. By keeping the cider chilled, you are essentially slowing down the chemical reactions that can alter its flavor over time.
I have personally experienced the difference in taste between a refrigerated and non-refrigerated hard cider. On one occasion, I left a bottle of cider on the counter for a few days before consuming it. The flavors seemed muted and the overall quality was not as enjoyable as when I had previously refrigerated the same brand of cider. This experience further highlighted the importance of refrigeration in maintaining the intended flavor profile of the cider.
If you plan on saving a bottle of hard cider for an extended period of time, refrigeration is highly recommended. However, if you intend to consume the cider within a relatively short period, such as a few days or weeks, storing it in a cool, dark place can also suffice. Just be aware that the flavors may gradually change over time, and the cider may not taste as fresh as when it was first bottled.
To summarize, while refrigeration is not mandatory for unopened hard cider, it can significantly prolong the quality and flavor of the product. If you want to ensure that the cider tastes as intended, especially if it lacks preservatives, refrigeration is the best option. Remember, cider is meant to be enjoyed fresh, and by taking the necessary steps to store it properly, you can enhance your cider-drinking experience.