Guinness drinkers have been imbibing fish bladder particles with their beer for more than 100 years, but that could change in 2016. Ireland's famous St. James Gate brewery, the home of Guinness, is in the process of abandoning isinglass, a gelatin collected from the air bladders of fish. It's been used to clarify alcohol, pulling yeast particles out of suspension, since the 17th century and is now primarily used for beer served in casks (cellar temperature kegs tapped without extra CO2). Guinness, however, uses isinglass in the brewery's tanks to separate the yeast from the beer and minimize the liquid lost when fermented beer is pumped out of the tanks and off the yeast.
This filtration process draws ire from vegans not just for the use of an animal product, but because as Guinness admits, traces of isinglass may be in the finished beer. Now Guinness's parent company, Diageo, is installing a new filtration at the Dublin brewery, and a statement says the plant is "seeking alternatives" for the equipment update in 2016.
Diageo says that St. James Gate brews the Guinness Draught (the classic version) sold in North America, Ireland, and the UK. Guinness, however, is a global brand brewed in 48 other countries that won't be changing how the black ale is filtered. It's also not the only Diageo-brewed beer with isinglass, other include Harp, Smithwick's, Guinness Extra Stout, Guinness Foreign Extra Stout, and Red Stripe.