How Climate Change Affects Beer Quality and Adaptation Options

Beer is the world’s third most widely consumed beverage, following water and tea, and it is the most popular alcoholic drink. Beer is made from three essential ingredients: barley, yeast, and hops.

Hops are combined with barley to give beer its distinct bitter flavour and aroma. The compounds in hops, known as alpha acids, contribute to this unique bitterness and affect the beer’s overall quality.

Hops have become a crucial component of beer-making, especially since the Industrial Revolution. Before this period, various herbs and spices were used to flavour beer. The introduction of steel and improvements in the brewing process during the Industrial Revolution made hops the favoured and essential ingredient in beer production.

Hops provide the distinct bitter taste and aroma for creating lighter, crisper beers like pale ales and lagers. The popularity of pale lagers has surged in Central Europe, particularly in regions such as Czechia, Slovakia, and Germany, where lager was first invented.

Consumer preferences for beer aromas and flavours depend heavily on high-quality hops. The rise of craft beer producers and small breweries is driving an increased demand for these superior hops. However, hop yields and alpha content—the compound responsible for beer’s bitter taste—are sensitive to climate conditions, particularly heat and moisture.

A 2023 study published in Nature, “Climate-Induced Decline in the Quality and Quantity of European Hops Calls for Immediate Adaptation Measures,” reveals that climate change—characterized by high temperatures, reduced precipitation, and drought—could soon affect the quality of hops. This change in hop quality may ultimately impact the beer’s flavour and overall quality.

Researchers studied hop production in European regions where 90% of hops are grown. They discovered that a temperature increase of 1.4°C, combined with a decrease in precipitation of 24mm, reduces annual yields by approximately 200 kilograms per hectare in Germany, the Czech Republic, and Slovenia.

Additionally, the alpha compounds in hops, which contribute to their bitterness, have declined by 0.6%. Furthermore, hops are now ripening about 20 days earlier than data collected before 1994.

Researchers comparing annual hop yields between 1971-1994 and 1995-2018 found a significant decline in production, ranging from 130 to 270 kilograms per hectare. The most notable drop was observed in Celje, Slovenia, with a decrease of 19.4%. This was closely followed by regions in Germany: Spalt at 19.1%, Hallertau at 13.7%, and Tettnang at 9.5%.

Projections for 2021 to 2050 indicate a further decline in hop yields, estimated to be between 4.1% and 18.4%, and a decrease in alpha content by 20% to 30% compared to 1989 to 2018. The most significant reductions in yield and alpha content are expected in the southern hop-growing regions of Tettnang, Germany, and Celje, Slovenia.

These projected declines are primarily attributed to rising temperatures and more frequent and severe droughts. The study forecasts a substantial decrease in alpha content per hectare, estimated at 25.3% to 39.5% compared to current values.

Climate Adaptation Measures

The study presented various climate adaptation strategies for hop growers to tackle the challenges of rising temperatures and increasingly dry conditions that could affect hop production and beer quality in the future.

These measures include expanding the area dedicated to hop cultivation by 20% to offset a potential decline in alpha acid content and overall hop production.

Additionally, changing the orientation of crop rows and combining irrigation with water-saving soil management practices have shown effectiveness in viticulture.

Relocating hops to areas with higher water tables, such as valleys or near streams, can facilitate better water uptake by plant roots. Growers can also consider adding drip irrigation systems or switching to more climate-resistant hop varieties.