As an expert sommelier and brewer, I can confidently say that drinking beer that has frozen is not ideal. While it won't kill you, there are several reasons why it is not recommended.
1. Flavor: When beer freezes, the water content in the beer forms ice crystals, which can damage the delicate balance of flavors in the beer. The chemicals responsible for giving beer its unique taste can be negatively affected by freezing and thawing. This can result in a dull or off-flavor in the beer when consumed.
2. Texture: The freezing process can also affect the texture of the beer. As the water freezes, it expands, potentially causing the beer bottle or can to crack or burst. Additionally, when the beer thaws, it may not regain its original carbonation levels, resulting in a flat and less enjoyable drinking experience.
3. Precipitation: Freezing can cause certain compounds in beer to precipitate out, leading to a cloudy appearance and an unpleasant mouthfeel. This can further detract from the overall drinking experience.
4. Quality: Generally, freezing is not a recommended storage method for beer. The rapid temperature changes and fluctuations that can occur during freezing and thawing can degrade the quality of the beer. This is why beer is typically stored and transported at controlled temperatures to maintain its integrity.
Personal Experience: I once accidentally left a bottle of beer in the freezer overnight. When I discovered it the next day, it had completely frozen. After thawing it, I found that the beer had lost most of its carbonation and had a slightly off taste. It was still technically drinkable, but it was far from enjoyable.
While drinking beer that has frozen won't cause any harm, it is unlikely to taste as good as it did before freezing. The flavor, texture, and overall quality of the beer can be negatively affected, making it a less enjoyable experience. It is best to avoid freezing beer whenever possible and store it in a cool, controlled environment to maintain its optimal flavor and quality.