As an expert sommelier and brewer, I can confidently say that all beers, including IPAs, can go bad if not refrigerated. While many people associate the freshness of IPAs primarily with the hop character, it is essential to understand that temperature plays a crucial role in maintaining the overall quality and flavor of any beer.
When beer is stored at warmer temperatures, it undergoes a process called oxidation. Oxidation occurs when beer is exposed to oxygen, and it can lead to a variety of negative effects on the flavor and aroma profile. The hop flavors and aromas, which are typically vibrant in IPAs, can quickly fade and become dull when exposed to oxygen and warmth.
Furthermore, the malt flavors in IPAs can also be negatively affected by warmer temperatures. Malt sweetness and complexity can diminish, leaving the beer tasting flat and lacking depth. This is particularly true for IPAs with higher alcohol content, as warmth can accelerate the breakdown of alcohol, leading to harsh and unpleasant flavors.
In my personal experience, I have come across instances where improperly stored IPAs have lost their hop punch and developed off-flavors due to prolonged exposure to warm temperatures. These beers often exhibit a stale or cardboard-like taste, lacking the crispness and vibrancy that is characteristic of a fresh IPA.
It is worth noting that refrigeration helps to slow down the oxidation process and preserve the beer's freshness. By keeping IPAs and other beers cold, you can extend their shelf life and maintain the intended flavors and aromas for a longer period.
To summarize, while hop flavors and bitterness are prominent aspects of IPA flavor that can degrade over time, it is essential to recognize that all elements of beer flavor can be affected by warmer temperatures. Malt sweetness, complexity, and overall freshness can suffer when IPAs are not refrigerated. Therefore, it is highly recommended to store and consume IPAs as fresh as possible to enjoy their full potential.