Guinness's History with Isinglass
For centuries, Guinness, like many traditional breweries, used isinglass in its brewing process. Isinglass is a gelatin-like substance derived from the dried swim bladders of fish. Its purpose was to clarify the beer by attracting and precipitating suspended yeast particles, which settled at the bottom of the vat and were removed. While the isinglass itself was largely filtered out, trace amounts could be found in the final product, rendering the stout unsuitable for vegans and some vegetarians.
The Brewing Process Then vs. Now
- Old Process: After fermentation, isinglass was added to the beer. The fish-derived collagen would bind to yeast and other particles, causing them to clump and fall to the bottom. The beer would then be racked, leaving a clearer liquid behind.
- New Process: The modern vegan-friendly process replaces isinglass with an advanced filtration system. This technology uses mechanical or plant-based means to remove excess yeast and sediment, ensuring the same quality and taste without animal products. The specific method is proprietary, but brewers often use alternatives like diatomaceous earth or other physical and adsorbent filters.
The Vegan Transition Timeline
The transition to a fully vegan-friendly Guinness was not an overnight change but a deliberate, multi-year process involving technological investment and careful product rollout by Diageo, Guinness's parent company.
- 2015: Diageo publicly announced its intention to eliminate isinglass from the brewing process following extensive lobbying from vegan and vegetarian groups. The plan was to install a new, state-of-the-art filtration system at the St. James's Gate brewery in Dublin.
- 2016: The new filtration system was implemented. By April 2016, the company confirmed that all kegs of Guinness Draught produced at St. James's Gate were brewed without isinglass. However, due to existing stock and ongoing production, bottles and cans were not guaranteed to be vegan at this point.
- 2017: Production of vegan-friendly cans and bottles began. Guinness advised that it would take time for the new, fully vegan products to reach worldwide distribution and replace all older stock.
- 2018: Diageo officially confirmed that all Guinness products worldwide, including Draught, Extra Stout, and Foreign Extra Stout, were now brewed without isinglass and are suitable for vegans.
Taste and Texture: Has Anything Changed?
A common concern among loyal Guinness drinkers was whether removing isinglass would alter the beer's iconic taste and texture. A spokesperson for Diageo, as well as master brewers, assured the public that the recipe for Guinness had not changed, only the filtration method. The new filtration technology was designed specifically to maintain the exact same profile. The rich, creamy head, for instance, comes from the nitrogenation process, which was not affected. Extensive trials confirmed that the taste was identical to the traditional, isinglass-filtered version.
A Comparison of Old vs. New Guinness
| Feature | Traditional Guinness (Pre-2018) | Vegan-Friendly Guinness (Post-2018) |
|---|---|---|
| Clarifying Agent | Isinglass (fish-derived) | State-of-the-art filtration system |
| Animal By-products | Contained trace amounts from filtration | Completely free of animal products |
| Suitability for Vegans | No, due to the use of isinglass | Yes, isinglass has been removed |
| Taste Profile | Classic Guinness taste | Unchanged; same classic Guinness taste |
| Texture/Mouthfeel | Distinctive smooth, creamy texture | Identical smooth, creamy texture |
Conclusion
For a brand with over two centuries of history, the decision to remove isinglass was a monumental one. The multi-year process, which was completed in 2018, demonstrates a responsiveness to changing consumer demands and ethical considerations. The change has successfully made Guinness accessible to a broader audience of vegans and vegetarians while preserving the taste and quality that loyal drinkers expect. The story of Guinness becoming vegan is a prime example of how even long-standing traditional companies can evolve with modern values. For more information on the brewing process, visit the official Guinness website.
