Why most wine and beer are not vegan, and how to buy the ones that are

A significant share of the world's wine and beer passes through a substance called isinglass, which is collagen extracted from the dried swim bladders of fish, mostly sturgeon historically and now more often other species farmed for the purpose. It has been used to clarify drinks since at least the eighteenth century, and it is still standard in British cask ale and common in wine, because it works quickly, produces a bright, stable finish, and leaves no detectable flavor behind. None of that has anything to do with taste. It has to do with electricity.

Fresh wine and beer are cloudy with suspended proteins, tannins and phenolic compounds left over from grapes, malt and yeast, and left alone they clear slowly over weeks or months as gravity does the work. Fining speeds this up by adding a substance whose surface carries an electrical charge opposite to the charge on the particles doing the clouding. In wine at typical fermentation pH, most haze-forming proteins sit below their isoelectric point and carry a net positive charge, so a negatively charged fining agent like bentonite clay binds them directly. Egg albumen works the opposite way: its protein is positively charged at wine pH, so it binds the negatively charged tannin and phenolic complexes that make young red wine taste harsh, forming clusters heavy enough to sink to the bottom of the barrel. Isinglass collagen behaves similarly to albumen, binding suspended particles into clumps, known as flocculation, that drop out within days rather than months. The agent itself is then racked or filtered away with the sediment, which is exactly why it does not have to appear as an ingredient: by the time the bottle is filled, almost none of it is still in the liquid.

Isinglass is most entrenched in British cask ale, known in the trade as real ale, where it is whisked into the cask to drop yeast out quickly enough for the beer to be ready to serve within days rather than the weeks that natural settling would take. Most mass-market lager, by contrast, is clarified by filtration rather than fining, running the beer through diatomaceous earth or membrane filters instead of adding a binding agent, which is one reason lager is more often vegan by default than cask ale is.

Guinness is the case everyone asks about, and the answer has a real date attached: Diageo phased isinglass out of Guinness Draught between 2016 and 2017, starting with kegs, and confirmed in 2018 that every format worldwide, including bottles and cans, no longer used it. The stout still gets its clarity from a combination of nitrogen dispense and filtration rather than fish collagen.

Some UK cask breweries have replaced isinglass with a proprietary silica-based product marketed as Super F, and others fine with gelatin or casein instead, so the beer verdict page and a check on the individual product still matter more than the word cask on its own.

The reason this whole category is confusing rather than simply disclosed comes down to one regulatory idea: a substance used during processing and then substantially removed before sale is classed as a processing aid, not an ingredient, and most food and drink labelling law only requires ingredients to be listed. Isinglass, gelatin and bentonite all qualify as processing aids in the United States, the United Kingdom and the European Union, which is why none of them is required on a standard wine or beer label anywhere.

Egg and milk are the exception, because both are recognized allergens, and allergen law works on presence of detectable residue rather than the ingredient versus processing aid distinction. Under the EU's current wine allergen labelling rule, Commission Delegated Regulation (EU) 2019/33, which replaced the original 2012 rule (Regulation 579/2012) in January 2019, a wine only has to declare egg or milk on the label if the fining residue is detectable above a floor of 0.25 milligrams per litre using the industry's specified test methods, so a bottle carrying an egg or milk allergen warning is a genuinely useful, legally meaningful signal that egg or casein fining was used, while the absence of that warning tells you nothing, since isinglass, gelatin and bentonite trigger no such requirement at all.

The EU separately overhauled wine labelling for reasons unrelated to allergens: rules requiring a full ingredient list and nutrition declaration took effect on December 8, 2023, applying to wine made from grapes harvested in 2024 or later, with older stock exempt until it sells through. Producers can print the ingredient list on the bottle or, more commonly, link to it through a QR code, and because fining agents are still processing aids, that ingredient list still will not mention isinglass or gelatin unless enough residue remains to also trigger the allergen rule.

The United States has no equivalent requirement yet. The Alcohol and Tobacco Tax and Trade Bureau proposed mandatory major food allergen labelling for wine, spirits and malt beverages in a rule published in January 2025, which would cover milk and egg fining residues, but as of this writing it remains a proposal, not law, and the agency's own timeline in the proposal allows five years after any final rule for compliance. In practice, in 2026 a US wine or beer label carries no legally required signal either way about fining agents, animal or otherwise.

Barnivore is the closest thing this category has to a public record, a crowd-built database of more than 60,000 wines, beers and spirits where volunteers email producers directly and post the answer, color-coded green, yellow or red, with a date stamp on every entry. Its honest limitation is that it is only as current as the last person who asked: a producer can change its fining agent the week after an entry goes green, and a small operation may never get asked at all, so treat an old, unconfirmed entry as a starting point rather than a guarantee.

The Vegan Society's Vegan Trademark is the strongest certification mark for this category specifically because its standard was written to cover processing aids, not just finished-product ingredients, which is precisely the gap that lets isinglass and gelatin go unlabelled everywhere else. A bottle carrying that mark has had its whole production chain, fining included, audited against it.

Short of a certification or a Barnivore entry, the single most reliable phrase to look for on a wine label is unfined and unfiltered, since a wine that skips fining entirely cannot have used an animal fining agent, though it will often be hazier and can throw sediment in the glass. It is also worth remembering that this phrase describes a process choice, not a house style: the same producer can bottle one cuvee unfined and another conventionally fined in the same year.

None of these tools is complete, and the gap matters more than most vegan buying guides admit. A processing aid used at trace levels is, by any reasonable measure of harm, closer to incidental contact than to an added ingredient, and plenty of committed vegans treat wine and beer fined with isinglass as an acceptable grey area precisely because the collagen itself is mostly gone by the time it reaches the glass, comparable to sugar processed through equipment that also handles bone char. Others treat the demand on the animal, a fish farmed and killed specifically to supply its swim bladder to a winery, as the relevant fact regardless of trace chemistry. Vegan Brief takes no position on where a reader should draw that line. What matters here is that the fining question is a genuine judgment call for many vegans rather than a simple pass or fail, and a guide that pretends otherwise is not being straight with you.

Cider follows the same fining logic as wine, since some producers use gelatin the same way a red winemaker would, while others leave cider unfined and cloudy on purpose; there is no separate rulebook, so the same unfined and unfiltered heuristic and the same Barnivore check apply directly.

Distilled spirits are vegan far more often than wine or beer, mainly because distillation itself, not fining, is what clarifies them, so isinglass rarely enters the process. The named exceptions are worth knowing rather than guessing at: cream liqueurs like Baileys use dairy outright, several honey-based liqueurs and honey-flavored spiced rums contain literal honey rather than a fining trace, and a handful of spirits, most famously the coffee liqueur Kahlua, use sugar processed by a supplier method the maker itself has confirmed is not vegan-friendly, widely reported as bone char refining though the company has not named the method, a practice covered in full on the bone char sugar page.

Mead is fermented honey, full stop, which puts it outside the fining question entirely and squarely inside the honey question covered on the honey verdict page, and the same applies to any beer with honey added after the boil for sweetness or aroma.

What isinglass, gelatin, casein and egg albumen actually are, and whether each individually counts as vegan in every context, belongs to their own pages: see isinglass, gelatin, casein and albumin, and for the standing per-drink verdicts, wine and beer. This guide's job was narrower: the mechanism that explains why the whole category is opaque, what the law in each market actually requires, and how to shop around the gap.