This is my third blog entry that deals specifically with the topic of hops. You can read the other two entries here and here.

Hops are one of the four essential ingredients of beer – the other three are water, malted barley, and yeast. As such, hops serve a number of functions. First, they act as a bittering agent. Second, they contribute to a beer’s aroma. Third, they have preservative qualities. There are three basic types of hops – alpha, aroma, and dual purpose. The primary function of alpha hops is to provide a beer with its bitterness, while aroma hops, as the name suggests, contribute to the aroma of a beer. Dual purpose hops combine bittering  and aroma characteristics.

I’ve been reading quite a bit about hops recently, as well as looking at some data, trying to identify how demand for hops might be changing in response to the growing popularity of craft beer. This interest stems from a project funded by the U.S. Department of Agriculture. The project, which includes colleagues from Rutgers University, Pennsylvania State University, and Simon Fraser University, is concerned with isolating the existence of what are termed agricultural clusters in the United States. As a piece of this much larger project, I have been looking at the impact that the growth of craft beer has had on the hops industry. In my research, I believe that I have identified three major impacts:

• An overall incease in demand for hops
• Demand for a greater diversity of hop varieties
• The geographic expansion of hop production, out of the industry’s Pacific Northwest core.

Let me now examine each of these in turn.

Incresed Demand for Hops

Not surprisingly, the volume of hops produced and used in a given year varies. A number of factors impacts these volumes, including weather conditions and fluctuations in demand from breweries. The chart below shows the number of pounds of hops held by growers, dealers, and brewers on March 1, for each year between 1948 and 2018. What is particularly noticeable about this graph is the sharp increase in hop stocks held by these three groups, starting in 2011. This increase corresponds quite nicely with the significant increase in the number of craft breweries that started around the same time (see second chart).

So why might more craft breweries result in an increased demand for hops? Well, a major reason is that many of the styles of beer brewed by craft breweries use more hops than the beers produced by macro-brewers such as Anheuser-Busch. A typical craft beer (if there is indeed such a thing) contains up to five times more hops than a macro beer. The first chart below shows the number of pounds of hops used to produce a keg of different styles of beer. Lagers and pilsners, the most common type of beer produced by macro-brewers, use 0.19 and 0.31 pounds of hops per keg respectively. All of the other styles of beer shown (except Ambers and Hefeweizen) use more hops. For example, IPAs use a pound of hops per keg, while Imperial Stouts  and Imperial IPAs use 0.87 and 3.8 pounds per keg respectively. As the second chart below shows, IPAs (which tend to use a lot of hops) represent over twenty-five percent of the American craft beer market.

Source: USAHops

Demand for Greater Diversity of Hop Varieties

Another feature of craft breweries is that they tend to use a greater variety of different types of hops than macro-breweries. As noted above, there are three basic types of hop – alpha, aromatic, and dual purpose. Macro-brewers, such as Anheuser-Busch, use primarily alpha hops when brewing beers such as Budweiser. Craft brewers, in contrast, use larger amounts of aroma and dual purpose hops. For example, an examination  of types of hops harvested in the state of Washington (the country’s leading hop producer) in 2007, shows that 73.2% of the harvested acreage were alpha hops. By 2017, alpha hops accounted for only 26% of the harvested acreage in the state. In contrast, aroma and dual purpose hops accounted for 40% and 25.9% of Washington hops in 2017, respectively (the numbers do not add up to 100% here because data disclosure rules meant that there were some hops that could not be placed in one of the three categories). This represents a fundamental shift in hop production, which reflects a fundamental shift in demand.

Another way that I analyzed the hop data was to examine what I term the Four Hop Concentration Ratio. This is a simple number that indicates the percentage of hop production accounted for by the top four hop varieties. Again, I looked at data from the state of Washington. In 2007, the top four varieties accounted 71.1% of hops harvested in Washington. In 2017, the top four varieties accounted for only 39.1%. These numbers suggest that Washington farmers were growing a greater variety of different types of hop in 2017, than in 2007. When I examined the top four hop varieties in each of the two years, I noticed another important shift. In 2007, the top four hops harvested in Washington were Zeus, Columbus/Tomahwak,  Willamette, and Galena. Three of these four (Zeus, Columbus/Tomahawk, and Galena) are alpha hops. Only Willamette are aroma hops. In 2017, the top four hops harvested in Washington were Cascade, Centennial, Simcoe, and Citra. None of these are alpha hops. Cascade and Citra are aroma hops, while Centennial and Simcoe are dual purpose.

The demand for diversity in hops reflects the diversity of beer styles and flavors/aromas that craft brewers produce. Different styles of beer require different combinations of different hop varieties. Even within the same style (e.g. IPA) individual brewers will combine different hop varieties as they seek to attain a particular flavor profile. Particular hop varieties are suited for Brewing specific styles of beer. For example, Azacca hops, which are alpha hops and impart notes of citrus, mango, and pineapple are ideal for pale ales and IPAs.  Willamette, in contrast, are aroma hops that have floral, fruity, and herbal notes and are most commonly used in pale ales, bitters, and stouts. And of course, in the hands of a creative and innovative brewer, who knows what hop varieties will be combined with what other hop varieties, to generate exciting tastes and aromas. Craft breweries tend to be quite open in revealing the hop varieties that they use in a particular beer. In fact, displaying the hop varieties used in a particular brew, on the can or bottle, is not uncommon. My oldest daughter bought me a variety pack of beer for my birthday last month. Two of the beers were from  Platform Beer Company in Columbus, OH. One, Chasing the Horizon, was a Black New England IPA, while the other, Seeing Sounds, was a small batch IPA. On the cans were the hops used in the brewing of each beer. In the case of Chasing the Horizon, four hop varieties were used – Callista (aroma), Simcoe (dual purpose), Eukanot (aroma), and Mosain (aroma) were used. For Seeing the Sounds, the hops were Galena (alpha), El Dorado (dual purpose), Citra (aroma), and Centennial (dual purpose).

Geographic Expansion of Hop Production 

A final trend that I have noted in my research on hops is the geographic expansion of hop production. The Pacific Northwest states of Washington, Oregon, and Idaho represent the heartland of American hop production. In 2017, these three states accounted for 95.5% of the acres of hops harvested in the United States. As few years earlier, in 2014, the three Pacific Northwest states had accounted for 97.7% of the acres of hops harvested. Gradually, in recent years, farmers in states outside of the Pacific Northwest have started to grow hops. Hops are now grown in twenty-nine states across the country. After, Washington, Oregon, and Idaho, the top three states for hop production are Michigan, New York , and Colorado. The map below shows hop growing States in 2017. Washington, Oregon, and Idaho are in red, and the orange states are the other states growing hops. The expansion of hop production outside of its core states is driven by demand from some craft brewers for locally-grown hops. At the same time, farmers see an opportunity to expand and diversify their portfolio of crops.

So, it appears that the increasing popularity of craft beer is changing the hop industry. Not only is there a demand for more hops, but there is a demand for a greater diversity of hop varieties. In particular, there is an increased demand for aroma and dual purpose hops, which, together, are now more popular than alpha hops. Finally, production of hops is increasing outside of the Pacific Northwest, as more brewers demand locally-grown hops.

Further Reading:

Schönberger, C. and T. Kostelecky. 2011. 125th Anniversary Review: The Role of Hops in Brewing. Journal of the Institute of Brewing, Volume 117, Number 3, pages 259-267.