Hops Are Not Easy to Understand, Nor Should Be Taken Lightly10 min read
Being one of the primary ingredients in most beer, Hops have changed significantly due to considerable commitments in research. Research continues to show the complexities of hops and how they affect beer. Of all the hops produced globally, the majority are used for bittering, flavoring, and adding aromatics to beers. Being recognized predominately as an antibacterial ingredient is passé.
“Hops are best known as the principal source of the aroma, bitterness, and flavour of beer, and the hops used today are for this purpose. They are from cultivated plants which have been developed by continuous selection over at least the last century,” writes P.R. Ashurst. What makes this plant so complex is still unknown entirely, which explains all the research underway currently. The craft beer industry is always looking for new hops to brew unique flavors, aromas, bitterness, characteristics, mouthfeel, colors, etc.
With approximately 267 varietals, this cultivar has come a long way from growing in the wild. Initially, they were recognized as edible plants with some medicinal value. Today hops are used for flavors and aromas, with aroma considerations gaining with craft beer enthusiasts.
As consumers’ tastes change, they demand new flavors and aromas, and the industry (brewers and growers/processors) must satisfy changing demands. Hop research is the way the industry responds.
New varietals are the most recognized way to create unique aromas and flavors. There must be some value to a new varietal; it could be increased yield or intensity of compounds in a cone. To create those flavors and aromas, a lot of research is ongoing, out of public view, which is critical to keep the whole craft beer industry vibrant and responsive. New plants will constantly be entering the pipeline for brewers. With research, hop production costs have also come down with higher yields and improved cone processing and growing practices.
With craft beer, it is interesting to reflect on changes, over time, in styles, practices, regulations, and consumer taste. Remember, it was Jimmy Carter in 1978 that launched a whole new industry. As consumers, we want a quality, flavorful and aromatic beer that is consistent and at a reasonable cost? This goal is to say, but not simply done. For example, I never knew research was being conducted on beer foam, and the importance of “lacing” patterns in the glass as the beer is consumed. However, foam and lacing are essential indicators of a quality beer. It is a function of hops that makes for improved foam and “lacing”.
Change, initiated from research, often facilitates growth, fosters innovation, and is driven by consumers. The hops industry is constantly looking for improvements to beer through research. In the last few decades, changes in an industry driven by consumers seem to focus on beer aromas. Craft beer consumers are at the forefront in demanding new flavors and aromas, and those characteristics come from hop industry research.
In 2008, 75-80% of hops centered around bittering; today, 83% are focused on aroma hops.
There have been discoveries made in hop compounds beneficial for medicinal products, food enhancements, and personal care products. However, today 97% of hops go for beer production worldwide. Interestingly, 66% of the world’s hops are produced in the U.S. This explains the importance of research efforts in the U.S. As an aside, China is a top beer producer.
Juxtaposed to the assumption that change is good, all change does also have a considerable risk component. It does not matter if the change is initiated by plant research or marketing research. My one favorite story about failure to understand the impact of change is the story of Schlitz. Schlitz (“the beer that made Milwaukee famous”) changed its recipe and production techniques to tweak costs and improve profits. Sufficed to say, they did not do research. We are only focused on hops research for this article because it is the most often discussed ingredient in beer; consumers always notice flavor and aromas from hops.
Today, the beer industry uses it for flavor and aroma; in the 1200s and 1300s people used ingredients such as fennel, sage, mint, cinnamon, and other plants to add a bittering component to an otherwise sweet and non-descript concoction. All was changed in the mid-1400s to mid-1500s when research found hops made beer suitable for commerce.
The first written mention of a plant with growth characteristics of hops was a wild hops species. The description was found in the writings of Pliny the Elder in 77 AD. Yes, there was a Pliny the Elder, a wealthy Roman citizen, a decorated military officer, and advisor to Roman rulers. After his military service, he was a prolific writer and researcher. He wrote 77 books on issues of nature, astrology, gold mining, medicine, etc. According to Martyn Cornell in Zythophile, neither Pliny the Elder nor his nephew Pliny the Younger researched wild hop species. Further, he did not suggest the wild climbing plant as a new ingredient for any beverage.
Pliny the Elder had nothing to do with hops nor using them in beer. It would be centuries before anyone used hops as a preservative for beer. But the story is interesting as folklore.
Mr. Cornell does elaborate on the folklore of Pliny the Elder and hops, “I think it’s somewhere between possible and probable that lupus salictarius was the wild hop plant. Pliny the Elder puts it among other wild plants from which the fresh shoots were harvested for cooking, like asparagus. While “willow wolf” (the Latin translation of lupus salictarius is “willow wolf”, so named by Pliny the Elder, is a good description of what hops are capable of in the wild as they grow up trees for support.”
Around 800 AD, hops offered antibacterial properties and some bittering activity that would preserve beer and eventually led to the commercial/trade value of beer. There is some evidence that hops were planted in gardens as early as 1000 BC and became cultivated as a commercial crop in Germany’s 12th or 13th century. Research on hops first came about to improve yields. In the late 15th century, hopped beer became an export in Europe.
In the 15th century, hops were used to make it possible to preserve the beer for trade. It was much later when brewers understood that the “invisible hand” that made beer was yeast. However, in 1680, yeast was found in beer using a microscope, but research gave beer makers the real secret of yeast to making beer-200 years later-thanks to Louis Pasteur.
America got into the hop business because of early immigrants coming from Europe, especially Germany. They brought the seedlings from roughly 4-5 varietals originating from wild hop plants over the centuries in Europe. The research found that Washington, Idaho, Oregon, and California were perfect climates and soil conditions for hops. Still today, many universities search for regional opportunities to be relevant in the hop industry.
As referenced above, in 1416, the English started using hops in beer as an antibacterial preservative, 100 years later, the Bavarian government mandated that hops were one of the allowable three ingredients in beer (yeast had not yet been discovered). We do not know about early research that moved hops to the forefront of beer ingredients.
Research today covers all matters relating to hops, from breeding and growing to harvesting and drying as well as plant chemistry and how compounds impact beer quality, as noted by The Institute of Brewing & Distilling literature. “Research in brewing plays a dominant role in the brewing industry in part because it provides information about the properties and composition of the cones. By understanding and then applying this knowledge in practice, brewers may tailor new beers in which specific properties are enhanced or suppressed for defined purposes.”
Although I am focused on beer, there is other research. As reported by Rexius, hops are used in many different soaps, shampoos, and Tom’s of Maine deodorants. Their effectiveness in calming skin irritation also makes them a popular ingredient in lotions and other skincare products. Research has taken hops into medicinal as well as culinary applications. Restaurants are now using hops as food spices. The Tattnang Hop makes a great tea. Finally, there is some cancer research using compounds found in hop resins produced in select varietals.
Uses in animal feeds offer benefits in antibacterial uses to preserve feeds and supplemental nutrient values.
Without using the scientific term, I wanted to illustrate a small sampling of research categories and how they affect craft beer. I just picked a few to show how detailed research has been used.
Varietals: Developed for specific purposes-climate adaptability, bitterness/aromas, yields, and farming practices.
There are indications that consumers are trending towards being more focused on beer aromas versus bittering IBU’s. As a result, there is more research on developing varietals that will have more aromatic activity from compounds within the cone and increased aroma properties. As a new varietal, Mosaic was a real success story, with a focus on aromatic properties.
Another focus is developing varietals that are drought-tolerant, produce increased yields, are easier to process, and are less prone to diseases and insects. Interestingly, this is often a regional issue; this forces considerable research effort on identical problems. Growers want varietals that improve yields and reduce production costs. That also addresses brewer requirements.
Introduced around 2013, by 2017, Mosaic became the 6th highest production hop in the U.S., noted Nick Carr at Kegerator. This hop is a patented varietal developed by Jason Perrault in Oregon. In total, through dedicated breeding research, it took about 14 years to get the plants to market.
According to Carr, Odell, Lagunitas, and Russian River were among the first (brewers) to experiment with this new hop, and it was a big hit. This highly researched hop variety is recognized for the breadth and intensity of its aromas.
Drying and Storage: This research is about keeping chemical compounds intact yet not letting high moisture content in cones lead to spoilage.
The University of Nebraska has been doing a lot of research on drying and storing cones at the time of harvest, which will preserve the properties of cones. Also, consider the brewers in this research. They need deliveries throughout the year, so storage is critical to ensure freshness and potency of alpha and beta acids which impacts the flavor and aroma of beer. With beer being produced throughout the year, brewers order hops as needed. Therefore, storage is critical in maintaining the consistency of the beer.
Environmental/Agronomics: Issues of climate, soil, pest, planting procedures, and trellising affect the outcome at harvest. Organic and sustainable farming is part of the list of grower needs.
Consumers are becoming very interested in organic craft beers. But organic hops are costly to produce because of U.S. standards for organic material production, requirements for nitrogen during the early growing season, disease control methods, weed, and arthropod remediation pressures. These are just a few of the things that make hops a challenging crop to grow organically.
This is a procedure of lowing bine trellis’ from 18 feet to 10 feet above ground level. Lower trellises will reduce labor costs, allow for quicker harvesting and reduce the environmental impact of pest control sprays and agronomic considerations. Current researchers are hoping to improve existing varietals to accommodate low trellis’. There are carbon footprint advantages to lower trellising as well.
Chemistry: It is estimated 75% of most hop research today goes toward a better understanding of how the compounds in hop cones: develop, get released in the beer-making process, impact brewing techniques, their impact on flavors and aromas, and how growing practices affect compounds development in the cone.
The Journal of the Society of Brewing Chemists reported on the importance of polyphenol compounds: “The novel hop polyphenol products offer great potential for innovative flavoring when combined with hop aroma essences.” This research also carries over to research on antioxidant values of hops. This is pointed out only to illustrate the depth and diversity of research to improve beer-better beer through chemistry!
There is cross-discipline research; and interdependency in all hop research. For example, the drying and processing techniques are starting to be studied relative to maintaining the highest intensities of essential oil compounds.
Resins in the lupulin gland, which gives beer flavors, aromas and bittering. Resins contain the acids that will convert in the boiling process of the wort. Resins (containing the alpha and beta acids) make up 15-30% of the lupulin gland, dependent on the varietal.
Interestingly dried hops may contain 3% essential oils with approximately 400 known compounds as of today. Some speculate essential oils can contain 1,000 compounds. The first research on essential oils was done in 1895. With minimal instruments to do research, most of the understanding of essential oil contributions to beer has happened in the last four decades.
According to IB&D, it is now known that the content and composition of the total essential oil of hops are affected by numerous factors such as hop variety, growth conditions, time of picking (ripeness), drying conditions, aerial oxidation, age, and storage conditions.
“Although much is known about hops and their function in brewing, new aspects continue to be revealed. Hop science has provided brewers with one of the main ways of meeting the abiding need to understand the nature of hops,” stated in IB&D study.
Craft beer is supported by a cast of domestic and international research scientists trying to understand a very complex ingredient in beer. From a top-down view, I have tried to explain how complicated the hop industry has become. That little cone contains mysteries that are yet to be discovered. Hopefully, this snippet of information does not diminish the fun of drinking a crafted glass of beer.