What Exactly Are Hops?
This month we are going to focus on hops. That little green cone that makes our beers so tasty is a relative newcomer on the beer scene. In the 9000 year history of brewing beer, it wasn’t until the last 1000 or so that hops made their way into our beer. These days, there are very few beers that are brewed without hops.
But what exactly are hops? They are a flowering seed cone of the female plant Humulus Lupulus which is in the Cannibidaceae family. This is the same family as marijuana and is probably why beer makes us feel so good. Hops grow in vines similar to grapes and are quite delicate and don’t survive long after they are picked. So they are usually dried soon after harvest and made into pellets for easier transport and storage.
Hops are used as a bittering agent, flavor additive and preservative in beer. But why would I want to make my beer bitter? I don’t want “bitter beer face!” It’s the same reason why we put sugar and cream in our coffee – balance. Coffee is naturally bitter so we add a sweetening agent like sugar or cream to balance out the bitterness. Malt in beer is sweet (think of high malt beers like Doppelbocks, Scotch Ales, and Abbey Dubbels) so to balance out the sweetness you add a bittering agent like hops. Better balance means you can enjoy it over a longer period of time before your palate gets tired of it. In the days before hops they used things like bog myrtle, gruit, sage and even dandelions. Hops used at the beginning of the brewing process add bitterness, hops used at the end of the brewing process (like dry-hopping) add flavor and aroma. Hops are a natural antibacterial and kill off unwanted bacteria in the beer without affecting fermentation. Without hops, beers have a shelf life of only a few days. With hops, beers can last for years without developing off flavors.
The earliest reference linking hops to brewing is from 822 in Northern France not far from modern day Belgium. Abbot Adalhard of the Benedictine monastery of Corbie wrote several volumes on how to run an abbey. He references gathering the necessary firewood and hops, which suggests that they were wild growing hops instead of cultivated hops. And if this didn’t supply enough, the porter should seek hops elsewhere in order to make enough beer for himself.
Hop varieties fall into two basic categories; bittering and aroma, and they do what their names suggest. There are some varieties that do both as well. Bittering hops, or alpha hops, are high in alpha acids and are ideal for bittering the beer. Aroma hops are used to add flavor and aroma and tend to be your modern rock stars of the hops world getting all the press and beer label mentions.
Important hop growing regions are Hallertau in Germany (which is still the largest hop growing region in the world); the valleys of Yakima, Washington and Willamette, Oregon in the US and counties Kent and Worcestershire in the UK.