We live in a world of constant change, and it is also seen in the brewing and hop industries. Rising energy costs, fluctuation of raw material quality and quantity due to climate change, increasing political pressure, together with evolving consumer purchasing behavior are some of the factors that we are facing these days. But changes offer new opportunities, and strong relationships and collaboration can make it easier to thrive together. Within the brewing industry we are all in the same boat.
To overcome these challenges, the main goal of the hop industry for the upcoming years is to stabilize the hop market by, for example, being able to forecast yield fluctuations as well as reduce business risks and generate more stable revenues. Finding new hop varieties with more stable yields and alpha acid content is one new and major field of investigation among hop breeding programs. But hop growers and traders are working also on other actions to mitigate harvest fluctuations, for example, the development of new irrigation concepts together with governmental organizations and authorities or researching and testing new agronomic solutions that could generate more efficient agricultural practices. Additionally, new research methods such as PCA (polymerase chain reaction analyses) are used to avoid breeding failures at an early stage and helps invest only in potentially successful varieties. Other technologies from the IT sector are also being used to achieve more targeted use of plant protection products and thus reduce costs and the environmental impact.
What can brewers do?
The industry has suffered two bad crops in a row in the last years (’22 and ’23), and listening to leading scientist, this will probably happen more frequently in the next few years. Extreme weather conditions not only have an influence on the production yield (kg/ha) but also on the alpha yield (kg α-acids/ha). If this happens more regularly, we could see shortages of some varieties. Therefore, the following question arises: what can brewers do to overcome more frequent bad crops or even shortages of a certain variety? The good news is that brewers have many opportunities to overcome these challenges.
Yearly crop data shows that not all hop varieties are affected in the same way by extreme weather conditions. Some varieties have shown a decrease in yield, whereas other varieties have had a moderate decrease under the same weather conditions. New hop varieties (for example, Titan, Tango, and Mandarina Bavaria), launched in the last years, are normally more heat-tolerant than landrace varieties. This means that their yield will be more stable under extreme weather conditions like high temperatures or low precipitation, thus reducing the risk of shortage if a bad crop happens. On top of that, new varieties have also lower greenhouse gas emissions, helping brewers reduce the carbon footprint of their beer and to work towards sustainability key performance indicators (KPIs). These varieties also offer a wide aroma spectrum to contribute to beer, even some aormas which were not available previously.
But the use of new hop varieties is not the only way to overcome the shortage. Brewers could also test new and experimental varieties already available on the market to substitute the current ones used in the recipe in case of a bad harvest. Having other varieties (new or old) implemented in a beer recipe can help to be more flexible and mitigate risks. If brewers create a recipe with a good blend of 2 or 3 different varieties of the same flavor, the annual variation can be covered, and the brewer can more easily adapt the recipe to the annual alpha and aroma impressions.
How to brew more efficiently?
When prices of raw materials and energy costs are rising, one of the main goals should be to get as much as possible out of one brew, thus working as efficiently as possible. It is common knowledge that some of the brewing steps are not the most efficient, for example, the isomerization during boiling or the dry hopping process. Research shows that hop pellets used during dry hopping can swell up to eight times their original volume or even higher (1). And if the brewers do not have suitable equipment such as a centrifuge, this beer cannot be sold as most of it runs down the drain with the hops.
To increase efficiency throughout the brewing process and to reduce beer losses, hop investigation centers from nearly all hop traders have launched a large amount of hop extracts designed for different steps of the brewing process. The common characteristic of hop extracts is the absence of vegetative material, which helps to reduce beer losses, improve utilization in terms of bitterness as well as aroma, reduce waste, and reduce shipping and storage costs. But by using liquid hop extracts, there is also an improvement in consistency, an increase in yields, faster processing times, an improvement in flavor, and a reduction in new product development time.
Liquid hop extracts to gain efficiency
Studies (2, 3) have shown that using CO2 hop extract on the hot side throughout the boiling process leads to a higher overall yield in beer production compared to pellets. CO2 extract is produced by the extraction of pellets with CO2 under pressure up to supercritical conditions. The product is a homogeneous and concentrated extract with excellent stability (over eight years). Due to the removal of vegetative material during extraction, the amount of liquid absorbed during boiling when using CO2 extract is reduced to a minimum. This is the most common extraction method used in hop industry and the base for most of the other advanced hop products.
Furthermore, pre-isomerized extracts can also help to reduce energy costs, as they can shorten boiling times or water-soluble extracts of iso-alpha acid or the light-stable rho-iso-alpha acid can only be added at the filter to adjust the bitterness at the end for another beer in the portfolio or to ensure a consistent bitterness. The addition of bitter acids at this late stage increases the utilization from around 33-35% when adding pellets for bittering at the beginning of the boiling process to around 80% when adding them before a final filtration step. For many years, hop traders have also been able to extract hop oils by distillation, and these can be added to beer even after filtration. With this type of products, the brewer can add aroma to the final beer with no addition of vegetative material and thus no beer loss. They are available in a wide range of formats as pure hop oils or blended with a carrier to make them soluble in cold wort or beer. Hop oils also have some added advantages, such as higher aroma yield, rapid new product development, and the possibility of easy and fast beer stream diversification.
Liquid Hops are a perfect solution for increasing efficiency
Thanks to the improvement of technology, hop research centers have developed flowable hop extracts ideal for their use in late and dry hopping, substituting pellets and improving the process in different aspects. A specially developed extract for dry hopping, for example, dissolves immediately in cold beer, reducing the contact and processing time and eliminating beer losses. According to Paul-Pax et al. (4), losses of 10.80 – 14.13 L per kg of hops are to be expected from the hops while dry hopping, depending on the variety. By using the designed liquid hop extract, the beer losses can be completely reduced while maintaining the original aroma. By replacing pellets in the late and dry hopping with extracts, the oxygen intake is also reduced to a minimum, improving the flavor stability of the beer. Moreover, Paul-Pax et al. (4) also observed no loss of iso-alpha-acid losses when using extract.
In summary, the implementation of new varieties as well as hop extracts in the recipes is key to overcoming some of the challenges that we are already facing and will become more important in the next years. Having a broad range of varieties accepted brings flexibility in case of a shortage of a defined variety. Moreover, hop extracts can help increase efficiency, improving the way we brew and thus saving energy and money. Above is a description of some hop extracts available on the market and how they can help you brew more efficiently, but there are many more. Just as the challenges are changing and the demands on production are changing ever more frequently and quickly, hop companies and researchers will also have to adapt. There will certainly be more new hop products in the coming years, which will not only make a contribution to the environment and the future, but also open up new possibilities for brewers. If you are interested in knowing more, contact your hop provider, and get technical support. Challenges may grow, but you will grow with them.
Literature
(1) Paul, L.: „Einfluss brautechnologisch relevanter Qualitätsattribute auf die analytischen und verfahrenstechnischen Eigenschaften eines fließfähigen Hopfenextraktes für die Kalthopfung“, Masterarbeit an der TU München, 2020.
(2) Mull, A. Founders Brewing Company. Hot Side Hop Usage – Optimization with Extract. Craft Brewers Conference 2016 - Philadelphia, PA.
(3) Visgil, M., McDonald, V., Algazzali, V., Byelashov, A. John I. Haas, Inc. Yakima, WA. Supercritical CO2 hop extract improves brewery process yield over hop pellets. Master Brewers Conference, 2017m Atlanta, USA.
(4) Paul-Pax, L., Novy, R., Schönberger, C., Tillner, J. BarthHaas GmbH & Co. KG. Dry Hopping with a flowable hop extract. Brewing Summit 2022, Providence, USA.
