(Note: This is a modified version of a piece I wrote for the Stormcloud Brewing Co. mug club members.)
As someone who has found themselves on a beer blog, I’m sure you have heard of hops. You probably know what they look like, and might even know that we have a few varieties of hops growing in the Stormcloud Brewing Company StormGarden. I’m hoping this article touches on a few things you might not know about this imperative brewing plant, and helps continue the growth of your beer knowledge.
There are four ingredients that unify nearly all beer – malt, water, yeast, and hops. Some people new to the world of beer are surprised that hops are in all beer styles, including dark, sweet, and non-bitter beer. In Germany in the 15th century there was a beer purity law adopted called Reinheitsgebot, which declared that the only ingredients that could be used in the making of beer were water, barely, and hops – with yeast being added after its discovery in the late 17th century. Reinheitsgebot “is now considered the world’s oldest, still valid food food safety and consumer protection legislation” (Oliver, 692). Though there are a few historical beers made without the use of hops (such a Gruit), the vast majority of modern beer styles require hops. Why? Hops are the ingredient in beer that provides its “backbone of bitterness, increases its microbiological stability, helps stabilize its foam, and greatly influences its taste and aroma” (Oliver, 459).
Okay, but what exactly are hops?
Hops are the flower of humulus lupulus, which is a climbing plant classified as a bine (yes, with a “b”.) They are members of the Cannabaceae family, which makes them the cousins of hemp, marijuana, and hackberry. One thing that makes the hop plant unique is that, “unlike most plants, individual hop plants are male or female” and “the best quality hops come from unpollinated female plants” (Cicerone, 22). They are native to Northern Hemisphere, and are believed to have originated in Mongolia “at least six million years ago” (Hieronymus, 46).
Originated in Mongolia? How’d they get all the way here?
According to beer journalist Stan Hieronymus, a European type of hop diverged from the Asian group more than one million years ago and a North American group migrated from the Asian continent approximately 500,000 years later. In his book The Story of the Pint, Martin Cornell calls the fact that we may never know how brewers discovered the importance of boiling hops “the greatest unanswered question in the history of brewing.” Before hops were used in beer brewers used gruit, an herb mixture created to provide flavor and bitterness. The use of gruit was gradually phased out in favor of the use of hops in a “slow sweep across Europe between the 11th and late 16th century” (Brown). In the American colonies, in addition to being used for brewing hops were used in salads, dyes, textiles, basket and wicker-work, and livestock feed. According to Michigan State University’s College of Agriculture & Natural Resources the first commercial hop harvest in the United States was in in 1791 in Massachusetts. By 1859 seven‐eighths of the nation’s hops were harvested in New York State. As people moved westward, so did the production of hops. Hops began to be grown in California in 1857, Washington in 1866, and Oregon in 1880. At present, the major hop producers are Washington, Oregon, and Idaho.
An incredibly brief primer on the science of hops:
In the image below, you’ll see the plant anatomy of a hop.
Inside the hop flower (or “cone”) is a yellow powder called lupulin powder, which contains the key compounds that bring flavor to beer – resin and essential oils. According to the Cicerone Brewing Ingredients and Process Coursebook, “Bitterness comes from the resins; aroma and flavor come from the oils” (23). In hop resin you’ll find alpha acids, which in natural form won’t dissolve in wort and aren’t very bitter. It takes the heat and agitation of the brewer’s boil to transform them into bitter iso-alpha acids. When brewers use hops for bitterness, they are typically added at the beginning of the boil and are referred to as “bittering hops.” Outside of bitterness, every other hop trait in beer (like aroma and flavor) come from the oils found in the lupulin gland. The Cicerone Brewing Ingredients and Process Coursebook also states, “hop oils typically constitute less than 2% of the weight of dry hops, and yet they contribute substantial flavor to the beer” (23). When you leave hops in for an extended time during a boil, most of the hop oils evaporate – this is why brewers add “flavor hops” roughly 30 minutes before the end of the boil and “aroma hops” roughly 10 minutes before the end, instead of adding them all right at the beginning.
Since you know that nearly all beer styles contain hops, you’ve probably figured out that there are a large variety of hops flavors. To get an idea, check out the hop flavor wheel below from Randy Mosher:
In the 2012 book For the Love of Hops, Stan Hieronymus lists 105 different hop varieties with unique flavor characteristics for brewing, but new hop varieties are being bred all the time. Additionally, the same hop variety grown in different regions impart different flavor characteristics. On the chart below, you’ll find the flavor and aroma profiles for some of the most popular hop varieties.
The next time you see a hop variety listed for a beer you’re drinking, I challenge you to try and identify some of the correlating aromas and flavors. Don’t get discouraged if there are characteristics you don’t pick up – scent and taste are subjective, and everyone experiences them differently.
Hop flavor can be so magical in beer that it can convince you there are othercompounds added, even when there aren’t. For example, those juicy, hazy beers out there? Most of them do not contain any fruit juice. This “juicy” effect is achieved by hop selection (typically ones with high oil content, bright flavor, and tropical or citrus characteristics), late boil or whirlpool additions, and dry-hopping. Take our Commander X-2 “Saizy” (hazy Saison) – we PROMISE there’s no grapefruit juice in it.
Additional hop-related vocabulary:
hop pellets – hops compressed into pellets that contain all the alpha acids and oils of whole hops and can be used at any time in the modern brewing process where whole hops would be used. The advantage of hop pellets is that they take up less room and are packaged to reduce degradation in storage. Most Stormcloud beer is made with hop pellets.
dry-hopping – the addition of hops to beer in the fermenting, conditioning, or serving vessel. This is done to intensify hop aromatics and add different aroma than hops added in the late boil.
IBU – stands for ‘International Bitterness Units’ and is the agreed-upon standard for measuring bitterness in beer. While it’s a good place to start when looking at a beer menu, “the usefulness of the IBU to the beer consumer is debatable. Once the beer leaves the laboratory context, many factors including other hop components, roast character, carbonation, water chemistry, and residual sugar, may exert such influences as to make the IBU an entirely unreliable indicator of actual perceived bitterness” (Oliver, 490-491). That said, I still try to drink my flights in the order of lowest to highest IBU to prevent palate fatigue.
cryo hops – (also known as lupulin powder) is a powder much more concentrated than whole hops or hop pellets, and it is recommended brewers use about half the amount of regular hops. One brewer calls them “all that you like about hops without the bitterness” (Hahn) where another thinks “it’s a less stable product. A beer hopped with 100% powder, the aromas and flavors drop off quicker than with pellets. So we like to use a mix of pellets and powder” (Krommydas). To date, the only beer Stormcloud has made using part cryo hops is the small batch Diabadass IPA.
hop extracts – a concentrated paste made of extracted hop resin and oils. Unlike whole hops or hop pellets, they do no need to be refrigerated and they are fully soluble.
harvest ale – a beer brewed specifically for the fall hop harvest, using fresh wet hops (instead of the year-round kilned hops.) Our 24:30 Harvest Ale is a good example, which is made using local hops from within a 30 mile radius of our brewery and brewed no more than 24 hours from when the hops are harvested.
hop yard – a plot of land for growing hops that consists of “a robust trellis system built of wire and telephone poles and reaching 18-20 feet in height” (Cicerone, 24).
Now that you’ve consumed an abundance of hop knowledge, I think it’s time for you to celebrate with a nice, hoppy beverage – namely Stormcloud beer!
References for this article:
Brown, Diane. “A brief history of hop and its uses.” Michigan State University, 2014, East Lansing, MI, http://www.canr.msu.edu/uploads/236/71516/ipm_academy_2014_intro_to_hops.pdf.
Cicerone. Brewing Ingredients and Process Coursebook. 2nd ed., Chicago, Cicerone Certification Program, 2018, pp. 22-26. Road to Cicerone.
Hahn, Fritz. “This concentrated hop powder is making brewers go crazy.” The Washington Post, 11 Aug. 2017, http://www.washingtonpost.com/lifestyle/food/this-concentrated-hop-powder-is-making-brewers-go-crazy/2017/08/11/510782f4-7e14-11e7-a669-b400c5c7e1cc_story.html?utm_term=.4288eb39ea11.
Hieronymus, Stan. For the Love of Hops. Brewers Publications, 2012.
Krommydas, Niko. “What Is Lupulin Powder and Why Are Brewers Obsessing Over It?” Edible Brooklyn, 28 June 2017, http://www.ediblebrooklyn.com/2017/what-is-lupulin-powder-and-why-are-brewers-obsessing-over-it/.
Oliver, Garrett, editor. The Oxford Companion to Beer. Oxford University Press, 2012, pp. 711-712.
Ernst Family at Horst Hop Ranch, 1946 – https://www.flickr.com/photos/osucommons/5765583236/
Inside the Hop Cone – Amy Martin
Hop Flavor Wheel – https://randymosher.com/Tasting-Beer
Flavor & Aroma Profiles of Popular Hops – https://vinepair.com/articles/flavors-aromas-craft-beer-hops/
Stormcloud Beer with Hops – Keirsun Scott