Fish products have been identified as serious allergens and people who are allergic to fish must avoid consuming foods made with fish or fish products. There is no evidence that isinglass (which is made from the swim bladders of certain fish) can cause allergenic reactions in people who are allergic to fish, and the European Food Safety Authority (EFSA) has ruled that it is not very likely to do so. However, many people may still wish to avoid drinking beer which has been clarified with isinglass. Two alternative compounds (which had shown promise in earlier experimental trials) for the clarification of cask ales and brewery conditioned beers were investigated. These were avian collagen and a pea protein extract. Both materials were observed to have a good clarification effect in laboratory scale fining trials and performed well in comparison to isinglass. Brewery trials were conducted using isinglass, avian collagen and pea extract as fining agents and sensory evaluation showed that there were few discernable differences between all three beers. The collagen alternative was ideal in that the data obtained from the laboratory, sensory and analytical trials show that it acted in a similar manner to isinglass and has no significant impact on beer quality. However, it was not thought that brewers would be receptive to using animal products in their beer. The pea extract also worked well and would make an excellent vegetarian alternative to isinglass, however further work is needed to scale up the production of the pea extract in order that it should become an economic option for use in the beer and wine industries.