Isinglass is fish-derived. Because it is a fining agent — added to clarify beer, wine and cider and then largely removed — it typically never appears on the finished label, making it a classic hidden ingredient. Beverages fined with isinglass are incompatible with vegan and vegetarian claims; unfined and alternative-fined products are widely available.
What it means for each mark
- VeganFish-derived — beverages fined with isinglass are excluded; bentonite-, PVPP- or plant-fined and unfined beverages pass.
- VegetarianDerived from fish, so excluded by vegetarian standards as well — the fining record decides, since the label rarely does.
Where it typically hides
- Cask ales and traditionally fined beers
- Wine and cider (traditional fining)
- Beverage blends built on fined base wines or ciders
What a certification review asks for
- The fining and clarification protocol for every beverage in scope
- A producer statement covering whether animal-derived finings were used at any production stage
- For switched processes: the date and records of the change to alternative fining
Alternatives
- Bentonite clay (mineral)
- PVPP (synthetic)
- Pea-protein and potato-protein finings (plant)
- Centrifugation and cold filtration — process routes that need no fining agent
Frequently asked questions
Why does isinglass not appear on beer or wine labels?
It is used as a processing aid and mostly removed before packaging, and most jurisdictions do not require processing aids on the label. A certification review asks for the fining protocol directly.
Are all beers and wines incompatible with vegan claims?
No. Many producers fine with bentonite, PVPP or plant proteins, or skip fining entirely. The production records, not the label, show which method was used.