If the earth gets hotter, we may not even be able to drink beer?

Climate change is becoming more and more severe. In addition to the melting of glaciers or the increasingly frequent super wildfires that we often see in the news, it will also affect our lives in a more profound way from places we cannot see - such as making beer more and more expensive and less delicious.

Beer image source: pixabay

Ancient history of beer

The history of people drinking beer can be traced back to the Neolithic Age, when planting agriculture just appeared and humans began to grow grains such as barley and wheat near settlements. However, grains such as barley and wheat are difficult to chew and digest, so they need to be boiled in water to make porridge.

These porridges may have fermented after being left standing for a few days inadvertently. During the fermentation, the yeast not only produced alcohol, but also a large amount of carbon dioxide. Thus , a new food with bubbles and alcohol taste (at that time, this primitive wine was more like porridge with wine flavor than wine) appeared.

The stone mortar in the Raqefet Cave may be the place where ancient humans brewed beer 13,000 years ago. Archaeologists found beer (porridge) residues in it. Image source: Wikipedia

With the rapid development of human brewing technology and the wide sources of beer-making raw materials (theoretically, beer can be brewed as long as there is starch, and grain crops such as barley and wheat naturally make beer easy to brew) , drinking beer has become a custom in ancient Egypt . According to historical research, when the Great Pyramid of Giza was being built, workers were given 4 to 5 liters of beer per person per day, and the ancient city-states on the Mesopotamian plains also used beer to pay workers' wages.

This habit later spread to Europe. Even though the nobles who drank wine and other fruit wines looked down on beer and once thought that beer was an unhealthy drink, this could not resist the love of the common people for beer. With the rise of the Industrial Revolution and the expansion of colonies around the world, beer became the third best-selling drink in the world after water and tea.

Bakeries and breweries in ancient Egyptian tombs. Image source: Wikipedia

Adding hops

It was because of this love that people in the Middle Ages tried to add various seasonings to beer, such as various herbs. In the process of continuous experimentation, hops appeared in beer.

Hops, formally known as "Hemiptera", is a herb that not only adds a unique bitter taste to beer, but also significantly extends the shelf life of beer because of its sterilizing function. Therefore, this ingredient has been fixed, and finally beer has become what we drink today.

Hop plants and hops Image source: Wikipedia

In simple terms, the beer brewing process, which has been improved by modern technology, is generally to mix a starch source (usually malted barley) with hot water to prepare wort, which is then boiled, hops are added during the boiling process, and yeast is added after cooling. The liquid that has been fermented and filtered by the yeast is beer.

The beer crisis under climate change

In modern times, with the intensification of climate change, the output and quality of the two major raw materials for making beer - barley and hops - have been affected.

First of all, barley is a food crop that ranks second only to corn, rice and wheat in terms of production, and 30% of its production is used to brew beer. The ideal temperature for barley is 15℃-20℃, and sufficient rainfall is required throughout the growing season (especially during the grain filling period).

Currently, about 60% of the world's barley is supplied by Europe, but with climate change, Europe often encounters extreme heat and drought in the summer when barley is flowering and filling . Excessively high temperatures can cause heat stress in barley, reducing its photosynthesis capacity, resulting in a decrease in yield. Not to mention drought, especially drought during the filling period, which can lead to severe crop failures.

In the summer of 2018, Germany experienced its highest temperature in 138 years of recorded temperatures, which ultimately led to the lowest barley production since 1994. Local farmers were forced to mix this low-quality and low-yield barley with barley from previous years and tried to sell it to breweries, but they were rejected by the breweries due to poor quality - this situation may become the norm in the future.

Barley Image source: Wikipedia

The second is hops, which are the ingredients that bring special bitterness and aroma to beer, and the bitterness comes from alpha-acids. A recent study collected data from 90% of hop-growing areas in Germany, the Czech Republic and Slovenia from 1971 to 2018, revealing the impact of climate change on hops.

Compared with the years before the 1990s, hops now mature 20 days earlier. At the same time, hop yields have dropped by 0.2 tons per hectare per year, while alpha-acids in hops have dropped by 0.6% since 1994.

Hops harvested and ready for beer making Image source: Wikipedia

According to current estimates, by 2050, the temperature in Europe may rise by 1.4°C compared to 1970, and precipitation may decrease by 24 mm. According to this data, by 2050, hop production may decrease by 4% to 18%, and the α-acid content will decrease by 20% to 31%.

The double decline in barley and hop production and quality will undoubtedly lead to a serious decline in future beer production and taste.

Although some people have already taken action, on the one hand they have begun to look for higher altitude mountainous areas to grow hops, and on the other hand they have begun to cultivate drought- and heat-resistant hop varieties , but whether these methods can work and to what extent they can work remains to be tested by time.

Conclusion:

In fact, the problem with beer is not a big problem. After all, even if the hops are gone, the α-acids in them can be chemically synthesized. But the real reality is the global food supply and the problems it causes for a series of related industries.

For example, barley, which is used as a raw material for beer, is more useful in making feed. If there is less feed, there will be fewer animals, and meat will naturally decrease, and the price of meat will naturally rise. In addition, the output of staple foods such as rice, wheat, and corn may also decrease, and even the output of cocoa beans used to make chocolate will decrease.

From this point of view, future climate change may affect every aspect of our lives. Are you ready to coexist with climate change?

References

[1]BINDEREIF SG, RÜLL F, KOLB P et al., Impact of Global Climate Change on the European Barley Market Requires Novel Multi-Method Approaches to Preserve Crop Quality and Authenticity[J/OL]. Foods, 2021, 10(7): 1592.

[2]BENTO VA, RIBEIRO AFS, RUSSO A,et al. The impact of climate change in wheat and barley yields in the Iberian Peninsula[J/OL]. Scientific Reports, 2021, 11(1): 15484.

[3]MOZNY M, TRNKA M, VLACH V, et al. Climate-induced decline in the quality and quantity of European hops calls for immediate adaptation measures[J/OL]. Nature Communications, 2023, 14(1): 6028.

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