Isinglass — Hidden Processing Agent — Is It Vegan?

Vegan status: Not Vegan

Also known as: Fish fining agent, Sturgeon isinglass, Carrageenan (different, but often confused)

Source

Derived from the dried swim bladders of fish, primarily tropical fish or historically sturgeon. The collagen in isinglass binds to yeast and tannin particles in liquid and causes them to sink, clarifying the product.

Used in

Beer (cask ale, some keg lagers), white wine, some ciders. Used as a fining agent to remove haze-causing particles.

Appears on label: No. In the EU and UK, isinglass does not need to be declared if it is not present in the final product as a residue. In practice, trace amounts often remain. From December 2023, new EU wine labeling rules require allergen disclosure, which may change this for some products.

How to avoid

Look for 'unfined' or 'vegan-friendly' on beer and wine labels. Apps like Barnivore.com list vegan-friendly alcohol brands. Most craft breweries now use Irish Moss, bentonite, or centrifugation instead.

Notes

One of the most prevalent hidden non-vegan substances. The Campaign for Real Ale (CAMRA) traditionally opposed vegan ale initiatives but has since shifted. Many major UK brewers including Guinness switched away from isinglass — Guinness went vegan in 2016. However, thousands of smaller breweries still use isinglass in cask-conditioned ales.