Lagers have only a limited amount of flavors and aromas. The reason is the limited number of lager yeasts available. However, that may change.
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The new yeast could give lagers completely new flavors.
Beer is an ancient drink known all over the world, and lagers are among its most popular types, but they only offer a limited number of flavors and aromas. New yeast strains bred using species discovered in Patagonia could change that, reports a new study in the scientific journal PLOS Genetics.
Beer is one of the oldest alcoholic beverages known around the world. In 2023, more than 166 billion liters of it were consumed worldwide, in 2024 its consumption could exceed 170 billion liters, according to the globalEDGE portal operated by Michigan State University (MSU).
The most popular type of beer is light lager. It is produced by bottom fermentation, in which a layer of yeast is located at the bottom and does not float on the surface as in top fermentation. This type of beer stabilizes at low temperatures and “lies” after fermentation for several weeks, from which its name was derived.
According to the Phys.org server, more than 90 percent of the world’s beer sales are lagers. They are characterized by a fresh taste, but offer only a limited range of additional taste notes and aromas. The reason is the limited number of commercially available types of lager yeast. Traditionally, yeast of the species Saccharomyces pastorianus is used, which was created by crossing two other species – Saccharomyces cerevisiae used for the production of wine or top-fermented beer and wild yeast of the species Saccharomyces eubayanus that lives on trees. However, lager yeast was bred hundreds of years ago, and its gradual improvement not only allowed it to adapt to lower temperatures, but also limited the range of flavors it can create.
A new study, developed by an international team of scientists from Chile and Sweden and published in the scientific journal PLOS Genetics, describes a new type of lager yeast bred using the yeast species Saccharomyces eubayanus discovered in 2011 on the bark of trees growing in the Argentinian part of Patagonia in southern South America.
The discovery of the yeast species S. eubayanus offered scientists hundreds of different strains of this species to choose from. They chose three that have properties advantageous for the production of lagers – the ability to withstand low temperatures (usually eight to 15 degrees Celsius), high efficiency in converting malt sugar into alcohol and the ability to create unique aromas.
“By crossing wild yeast strains with top-fermenting beer yeast (S. cerevisiae), we created a completely new lager yeast that retained the good fermentation abilities required for commercial brewing, but at the same time brought new flavors and aromas that had not been seen in lagers before.” Jennifer Molinetová, the lead author of the study at the Universidad de Santiago de Chile, told Phys.org that the aroma of beer brewed with new yeast strains was spicier with stronger notes of herbs and cloves.
The new lager yeast also expands biodiversity in the brewing industry, which may save the industry from a similar fate to that of Cavendish banana growers. Bananas of this variety are grown on large monoculture plantations, and their growers have been battling a fungal mold capable of wiping them out for a long time. The Food and Agriculture Organization of the United Nations (FAO) reports that they make up 47 percent of all bananas grown and are virtually the only variety imported to the US and Europe. They also make up a large part of banana consumption in China and India, so their extinction would have a significant negative impact on the whole world.
Source: vat.pravda.sk
