Guinness is about to change a 256-year-old recipe to make it vegan-friendly.

After years of pleading, the Irish beer maker is heeding the call of Guinness-loving vegans and will stop using fish bladders to filter its iconic dark stout, reported The Times UK.

The fish collagen, also known as isinglass, has been used since day one at Guinness, to help yeast settle faster and clarify the liquid. It imparts no taste, nor does it alter the beer’s texture.

But the use of fish byproducts makes the stout unsuitable for vegans, which has spurred many a Guinness lover to appeal to the company via online petitions.

On change.org, a Manchester fan, for instance, managed to collect 1,715 signatures asking the brand to make the beer vegan-friendly.

“There are many alternatives to isinglass which do not contain any animal products and are comparably effective. Switching would allow the world's billion-plus vegetarians to enjoy one of the most delicious alcoholic drinks there is -- and it wouldn't even affect the taste,” wrote Tom Jones.

The new fish-free filtration process is scheduled to be implemented in 2016.

“Whilst isinglass is a very effective means of clarification, and has been used for many years, we expect to stop using it as the new filtration asset is introduced,” a Guinness spokesman told The Times.

Want to raise an animal byproduct-free pint? Animal rights group PETA has a list of vegan-friendly beers at http://www.peta.org/about-peta/faq/which-beers-are-suitable-for-vegans/.