We’ve discovered strange beer flavors using genetics

One of my favorite summer pastimes is enjoying a cold beer at a bar with friends after work. But not just any beer – it has to be beer. And I am not alone. With its crisp and refreshing characteristics, lager accounts for more than 90% of the global beer market.

However, all lager beers taste quite similar and the variety of flavors and aromas is limited. This is mainly due to the small number of commercial yeasts available for production. But what if we could break free from these limitations and create completely new and exciting flavors?

Our recent study, published in PLOS Genetics, takes an approach that does just that, using wild yeasts from Patagonia to create a new lager yeast.

The problem with traditional lager yeast

Yeasts are single-celled fungi that ferment sugar into alcohol and carbon dioxide. For centuries, humans have consciously or unconsciously used yeast to produce fermented foods such as wine, beer, and bread.

traditional lager yeast, Saccharomyces pastorianosis a hybrid crossing between two types of yeast: S. cerevisiae (used to produce wine and beer) and S. eubayanus (a wild species found on trees).

Hybrid lager yeast was domesticated hundreds of years ago and has since been optimized for cold brewing.

However, this long history of selective breeding, similar to what we see in our livestock, crops and pets, has also limited the genetic diversity of lager yeast, resulting in a very limited range of available flavors and aromas, with little room for It leaves innovation.

Enter wild Patagonian yeast

Until a few years ago, it was impossible to make a new beer simply because the parent strain of lager yeast, S. eubayanushad not yet been discovered.

But in 2011, this species was found on the bark of Patagonian trees in Argentina. Since then, hundreds of species have been isolated from the forests of Chile and Argentina, which have a staggering genetic diversity.

Our research used this genetic diversity to expand the flavor and aroma for lager. We focused on three in particular S. eubayanus Lineages from southern Chile that had distinctive characteristics and were very promising for brewing beer. They are tolerant of cold temperatures, which are necessary for lager production, which usually takes place between 8 and 15 degrees Celsius. They were also efficient in converting maltose to alcohol and carbon dioxide as well as producing unique aroma profiles.

By creating hybrids of this wild lineage with plum yeast S. cerevisiaewe developed an entirely new yeast that not only retained the strong fermentation characteristics required for commercial brewing, but also offered new flavor profiles never before smelled or tasted in lagers.

Brewing the future

However, our first attempts to produce new hybrids did not produce strains with the characteristics we wanted – they were not adapted to the fermentation conditions. But it can happen.

However, we can improve this process in the laboratory. We call it empirical evolution. We grew the new hybrids in a brewer’s yeast-like environment for six months to increase their brewing performance. This created several new species thanks to the natural process of evolution.

Then, we selected strains that showed superior fermentation capacity and the ability to produce higher alcohol levels. We also found that hybrids that inherited mitochondria (the “engine” of the cell) S. eubayanus The parents showed more evolutionary potential and became more efficient in converting sugar to alcohol and were able to create higher alcohol content.

But the most exciting thing for us was that the new lager strains we made showed a wider range of aroma profiles towards a herbal, spicy and clove-like character.

Implications for the beer industry

We believe that our new hybrid yeast has the potential to revolutionize beer brewing. Craft breweries in particular can use these varieties to develop unique lager styles and differentiate their products in a crowded market, even attracting those who prefer fruitier, happier ales (such as New England, India, and Belgian Pale).

We have already used the new hybrid strains for small-scale (500 liter) beer production in association with local breweries in Chile.

Our study not only opens up new opportunities for the brewing industry, but also emphasizes the importance of biodiversity in brewing. By taking advantage of the natural genetic diversity of wild yeasts, we can create innovative products that meet the evolving tastes of consumers.

As the beer industry continues to grow and diversify, these new hybrids could play an important role in shaping the future of beer.