When it comes to brewing, yeast is more than just an ingredient—it’s a cornerstone of the process. The right yeast transforms wort into beer, imparting flavour, aroma, and character unique to each style. With so many yeast strains available, it can be daunting to choose the right one. This blog explores key yeast types—Sour, Kveik, Lager, and more—and their unique benefits for brewers.
Understanding the Role of Yeast in Brewing
Yeast is a single-celled organism that ferments sugars, producing alcohol and CO2. Beyond fermentation, yeast strains contribute distinct flavours, aromas, and textures to the final product. Selecting the right yeast is critical, as it can enhance or completely transform the style you aim to brew.
1. Sour Beer Yeast
Key Traits: Tartness, complexity, and unique flavour profiles.
Sour beer yeast, often combined with lactic acid bacteria like Lactobacillus or Pediococcus, creates the tangy and puckering flavours iconic to sour ales. Some strains, like Brettanomyces, add funky, earthy notes. Sour yeast is highly versatile and pairs well with fruit additions, barrel aging, or blending techniques.
Benefits:
- Creates bold, tart flavours that stand out.
- Adds layers of complexity for brews like Berliner Weisse, Gose, and Lambic.
- Pairs well with innovative and experimental brewing techniques.
Pro Tip: Sour yeast requires careful handling to prevent cross-contamination with clean beer yeast.
2. Kveik Yeast
Key Traits: High-temperature fermentation, fast results, fruity esters.
Originating from Norwegian farmhouse brewing traditions, Kveik yeast has become a brewer’s favourite due to its resilience and speed. It ferments cleanly at temperatures up to 40°C (104°F), producing fruity, tropical notes. Kveik strains are ideal for a variety of beer styles, from IPAs to farmhouse ales.
Benefits:
- Extremely fast fermentation—often completed in 1–3 days.
- Fruity esters like citrus, mango, or pineapple, depending on the strain.
- High alcohol tolerance, making it great for strong ales.
Pro Tip: Kveik yeast thrives in hot conditions, reducing the need for precise temperature control during fermentation.
3. Lager Yeast
Key Traits: Clean, crisp, and subtle.
Lager yeast, or Saccharomyces pastorianus, ferments at cooler temperatures (7–13°C or 45–55°F) and is known for producing clean and crisp flavours. This bottom-fermenting yeast allows malt and hops to shine, making it ideal for pilsners, bocks, and other lager styles.
Benefits:
- Produces smooth, clean flavours with minimal esters or phenols.
- Perfect for showcasing delicate malt and hop characteristics.
- Creates highly drinkable beers with a polished finish.
Pro Tip: Lager yeast requires extended fermentation and conditioning times to develop its full potential. Patience is key!
4. Ale Yeast
Key Traits: Versatility, diverse flavour profiles.
Ale yeast, or Saccharomyces cerevisiae, is the most commonly used yeast in brewing. It ferments at warmer temperatures (15–24°C or 59–75°F) and is top-fermenting, producing a wide range of flavours. From fruity esters in Belgian ales to the clean finish of American pale ales, ale yeast offers endless possibilities.
Benefits:
- Works well for a wide variety of beer styles, including IPAs, stouts, and porters.
- Easy to use with forgiving fermentation requirements.
- Allows for creative experimentation with adjuncts and flavours.
5. The National Collection of Yeast Cultures (NCYC)
Key Traits: Unparalleled yeast diversity, research-backed strains.
The National Collection of Yeast Cultures (NCYC) is a globally recognised resource for brewers, offering an extensive catalog of yeast strains for every brewing need. Whether you’re seeking traditional strains for classic beers or innovative options for experimental styles, NCYC provides strains backed by scientific research and rigorous quality control.
What NCYC Can Offer:
- Diverse Yeast Bank: Thousands of strains, including wild and rare species, ideal for sour, ale, lager, and specialty styles.
- Custom Solutions: Yeast selection tailored to specific brewing challenges, such as high attenuation or stress tolerance.
- Research and Support: Access to technical expertise and in-depth knowledge of yeast biology.
- Preservation Services: Safeguard proprietary yeast strains for long-term use.
Benefits:
- Broadens brewing possibilities with unique and rare yeast strains.
- Ensures consistent quality for commercial brewers.
- Supports innovation through access to cutting-edge research and yeast customisation.
Pro Tip: Collaborating with NCYC can help breweries stand out by leveraging rare or bespoke yeast strains for unique beer profiles.
Choosing the Right Yeast for Your Brew
When selecting yeast, consider the following:
- Style Requirements: Does your beer call for a clean lager profile or bold fruity esters?
- Fermentation Conditions: Can you maintain the required temperature range?
- Flavour Goals: Do you want your yeast to dominate or play a supporting role?
Conclusion
Yeast selection is one of the most exciting aspects of brewing, offering nearly limitless possibilities. From sour and tart beers to clean lagers and experimental creations, choosing the right strain ensures your beer stands out.
