A recent study published in Nature Communications reveals that climate change is posing a significant threat to the production of aromatic hops in Europe, which are essential for giving beer its characteristic bitterness.
The prized European varieties of hops are extensively utilized by brewers worldwide. However, the study highlights that the increasing temperatures and decreasing rainfall are adversely affecting hop yields and reducing the concentration of the compounds responsible for the refreshing bitterness in beer.
Researchers arrived at these conclusions by examining data from five locations in the Czech Republic, Germany, and Slovakia, which, along with Poland, are the primary hop cultivation regions in Europe, according to study co-author Miroslav Trnka.
Comparing data from the years 1995 to 2018 with that from 1971 to 1994, the study discovered that hop yields decreased by 9.5% to 19.4% at four sites, while remaining stable at the fifth location. Additionally, the concentration of the bitter compounds, known as alpha acids, decreased.
Based on this data, the researchers predict a potential decline in yield ranging from 4% to 18% when compared to the period from 1989 to 2019. They also anticipate a drop of 20% to 31% in the concentration of alpha acids as temperatures continue to rise and rainfall patterns are affected.
Given the expected increase in droughts in central and southern Europe, the study suggests that it will be necessary to increase the area dedicated to aroma hops by 20% compared to current production to compensate for the potential decline in potency and yields. Urgent adaptation measures are required to stabilize international market chains, including relocating crops to more suitable regions or implementing irrigation.
Hops farmers are attempting to adapt, but Trnka notes that their options are limited because hops require a specific combination of climate and soil. Furthermore, the introduction of genetically modified plants designed to thrive in warmer temperatures and drought conditions is prohibited in Europe.
Brewers may also need to modify their techniques to accommodate the reduced bitterness in hops as a result of these changing conditions.