Finally, something to get the masses listening – climate change is impacting beer!
A recent study from the Czech Academy of Sciences investigated how climate change might be affecting hops and the news is fairly brew-tal. Using historical data and climate change projections, they investigated shifts in the quantity and quality of hops across some of Europe’s key hop-growing regions across Germany, the Czech Republic and Slovenia.
To predict future climate conditions, scientists use data-heavy climate change models based on a range of scenarios that are dependent on the changes we make as a society. Regardless of the scenario, it’s likely that we’ll experience more frequent extreme weather events, with some regions experiencing drier conditions due to rising temperatures and shifts in rainfall.
At its core, beer is an agricultural product as it requires hops and cereals (such as barley and wheat) for production. Given what we know about extreme conditions and drought on plant growth (just ask the strawberry plants that I keep forgetting to water), it’s not a surprise that climate change is having an impact on these crops. Farmers and brewers in the USA are already feeling the burn from the changing climate and studies on barley have found reduced yields in response to increased temperatures. But what’s the story with hops?
The researchers found that the European hop-growing region will experience drier conditions, leading to hops ripening earlier in the season and reducing the harvest yield – in other words, fewer hops.
However, it’s not only the quantity but also the quality of hops that could be affected, with the alpha acid content likely to decline. Alpha acids are the key source of bitterness in beer. When hops are dropped into a warm solution, the alpha acids isomerise (the transformation of a molecule into a different isomer) into iso-alpha acids, and therefore bring beer’s iconic bitterness.
The alpha acid content is varied by a range of factors, such as hop variety, climate, and growing region, so the brewer needs to adjust the recipe depending on that year’s harvest. Lower alpha acid content will mean that they need to use more hops to make consistent beer, which will increase production costs. So, climate change will result in reduced hop yield, but also increased use by brewers – you can see how this might be a supply problem.
Many of the traditional hop varieties grown in these regions, such as Hallertau, are key noble hops used in a range of iconic beers with a rich history. Does this mean the demise of those beloved beers and styles?
“Without adaptation measures, the availability of aromatic hops will be reduced. Hops would be more expensive and less accessible to the average beer drinker,” says the study’s lead author Dr Martin Mozny from the Czech Academy of Sciences.
“Breeding new varieties is one way to maintain sufficient hop production. However, if the potential of hop-growing areas is better exploited, incredibly shady areas close to watercourses, traditional varieties can still be grown,” he explains.
“In [lower latitude] hop-growing areas, there will be greater pressure on the profitability of production. Newly bred hop varieties will have a better chance here. The more [higher latitude] existing areas will have a competitive advantage, and it will be up to them to exploit it.”
Dr Mozny’s words had me dreaming about the capacity of new hop varieties to fight the impacts of climate change, but are hop breeding programs a viable solution?
“Directly targeting adaptation of breeding populations or deploying material to cope with or mitigate the impact of climate change is well beyond the capability of most programs,” says Dr Simon Whittock, Agronomic Services Manager at Hop Products Australia (HPA).
“By operating selection programs in growing environments aligned to your production areas you do achieve some adaptability, but that is a pretty indirect way of addressing climate change.”
Currently, the United States Department of Agriculture (USDA) are using controlled environments to map hop plant responses to heat and water stress. Dr Whittock suggested that hop production in these artificial environments could be one solution to climate change and hop breeding programs would be fundamental to the success of this approach.
“HPA are active participants in a corporate Sustainability Certification Scheme (UN Global Compact) that is designed to promote sustainable development,” says Simon.
“[Our] breeding program is based in two diverse growing environments, so is well placed to identify material that has superior environmental adaptability.”
Alternatively, it would be possible to create alternative selection environments by limiting water, fertiliser or herbicide use, but Simon warns that a breeder going down this path would have to be very careful about the target environment they choose.
“Breeding is such a slow process and setting the wrong parameters could mean they end up with material that is poorly adapted to the reality 15-20 years in the future.”
Even if they somehow did manage to Nostradamus it and perfectly predict future climate conditions, Simon doubts that adapting hops would make much of a difference, especially “in the face of changes to the frequency and intensity of extreme events such as floods, fires, storms, drought and heat.”
Of course, while the study suggests that climate change may impact beer, brewing itself is a significant contributor to climate change. Carbon dioxide (CO2) is a primary metabolite of fermentation, and brewers regularly use CO2 to carbonate beer or purge tanks to reduce the risk of oxidation.
Is this some kind of positive feedback loop, where beer is driving a carbon dagger into its own heart? That might be a little dramatic – but it does make us ponder about the uptake of sustainable practices, such as CO2 recapture technology, amongst independent craft breweries.
So as you’re reaching for a cool crisp beer in the scorching dystopian future, will it taste any different because of climate change? Probably not. But it will likely be more expensive as we struggle to adapt and grow crops in a changing global environment… (and deal with a burgeoning excise tax, of course).