Be in cases or schools, beer and fish travel in packs. Beyond that, fish don’t have much in common with refreshing, bubbly, and intoxicating brews. That is, unless the beer is made with isinglass, a surprisingly common fish-derived ingredient used during the beer brewing process. Because isinglass doesn’t have a strong or noticeable flavor of its own, you might not even know that it’s hiding in your favorite beer.
Isinglass is a type of collagen derived from the swim bladders of fish. Swim bladders are internal organs that help fish control their buoyancy in water, but in brewing, they serve a much different purpose. Isinglass is used as a fining agent (a substance that removes impurities from liquids) to clarify beer by binding to unwanted particles like yeast, proteins, and sediment, causing them to sink to the bottom of the barrel or tank. More simply stated, beer is filtered through isinglass for a clearer, more polished, and less hazy appearance. Although isinglass is removed from the finished product, traces can remain, making isinglass fining problematic for vegan and vegetarian beer drinkers.
How to know if there’s isinglass in your beer
Whether you follow a plant-based lifestyle or find fish-filtered beer too peculiar to drink, it’s important to know if your go-to beer is made with isinglass. Unfortunately, the fishy facts aren’t as straightforward as you might think. The American Alcohol and Tobacco Tax Trade Bureau doesn’t require breweries to include nutrition labels or ingredient lists on their product packaging, which makes fishing for isinglass-free beer tricky.
You may be able to contact smaller breweries specializing in craft beers to ask them about the products used in their production process. Larger breweries specializing in commercially produced beers can be harder to get in contact with, but online beer forums can help you make informed decisions on which beer works best for your preferences and dietary restrictions. Frequented by vegan beer, wine, and liquor connoisseurs, Barnivore is a vegan booze guide available online and in the app store that informs users on which alcoholic beverages are free from animal-derived ingredients. And if isinglass beer sounds fishy, just wait until you hear about wine.
