So What's the Deal with Hops?
Hops are such an integral part of the anatomy of a beer, and a critical component of contemporary beer enjoyment that we don’t often stop to ponder its origins, what a hop actually is, and exactly why it has become so central to beer culture and to our entire idea of what beer is. In fact, there is so much hop-related information, this short blurb by the Geek is really just to give a very brief glimpse into the hop universe.
The hop is actually the flower of the hop plant, Humulus lupulus, and is a member of the plant family Cannabinaceae which includes such illustrious members such as hemp and marijuana. No surprise then that some hop aromas in beers have variously been described as “herb-like”, “oregano”, or just “weedy”. While there are quite a few more hop species, most hops used in beer are descended from or related to the Humulus lupulus, or the “low creeping wolf”. The hop plant is indeed a creeper, and in hop farms, the above-ground portions of the plants or bines are encouraged to climb up vertical lines of string or rope mounted on frames. The hop plants climb up these supports with the help of stiff hairs that help the rapidly growing plant hang on the frames or trellises. At its peak growth, a hop plant grows 50cm every week. Hops like grapes tend to grow in scenic latitudes and hop farms like vineyards are often tableaux of rustic farmland. Considering that hops will grow in climates from Israel and Iraq to as far north as the United Kingdom, an area which also covers most of Europe in the northern hemisphere and includes Tasmania in southern, you are likely to stumble upon farmland covered by rows of lush green, joyously bursting forth in verdant vine-like growth during the summer. In Asia, the closest reference would be pepper plants on a farm where the plants are cultivated in a similar fashion. Mid-late summer is when the hop cones or flowers are harvested. The cones were traditionally kilned or dried in a building known as an oast or oast house. Kilning hops was a good way to help keep the hops from spoiling while preserving the hop cone’s bittering properties.
Every hop cone has two primary properties, compounds that make beer bitter, and compounds that make beer aromatic. Bittering compounds undergo a chemical change known as isomerization when they are boiled resulting in compounds that are bitter to taste. This process takes a while and so when hops are used for bittering they are usually added pretty early in the boiling process to allow more time for isomerization to take place and for more bitter flavor to develop in the final beer. Isomerization also makes these hop compounds water-soluble as hop oils are not naturally so. Some fresh hops also have the special ability to make beer incredibly aromatic, just think of that juicy hazy IPA that has a nose redolent with lychee, guava, tangerine, grapefruit, and lemon zest! The aroma compounds in hop cones are sensitive to heat and are described as chemically volatile. They tend to degrade with exposure to oxygen, time, and heat. To get these aromatics into the final beer, brewers will often add hops to the beer after the brewing processes that involve heat or boiling, in a process known as dry-hopping. In fact, the New England IPA or hazy IPA style involves intense dry-hopping, so much so that the final beer not only is incredibly aromatic, it is also hazy or cloudy! The visual of a hazy orange liquid, accompanied by the intense tropical and citrus aroma, conspire to give the impression of juiciness when a New England IPA is finally tasted.
You might ask why it is necessary to make beer bitter in the first place. If you consider that all beer starts as a thick syrup made from boiling malted grain, the addition of something herbal or bitter might be necessary to balance the palate to make this beverage tolerable and even enjoyable. Indeed, as beer has evolved, the people who’ve made beer have tried all and sundry to balance the inherent sweetness of beer, even resorting to using gallbladders of oxen in the brew. Giving balance to beer to enhance its consumption in quantity has ever been the goal of the brewer, and how this balance is achieved is often a closely guarded trade secret of every brewery. Gruit, a proprietary mix of herbs, was used widely before hops became a common ingredient..and how this gruit was made at each brewery was a closely guarded secret. Another interesting bit of history surrounding the quest for balance and drinkability in beer is that laws had to be put in place to prevent brewers from spiking beer with adulterants that were at best unsavory and at worst unsafe! In this, we have the Germans to thank for their reverence for beer by being a fastidiously anal-retentive nanny state and enacting the Reinheitsgebot of 1516, stating quite clearly that beer was to contain nothing else other than barley, hops, and water...Germans and their need for purity. I’m being facetious here because, at the end of the day, regulation is necessary to protect the consumer...and to make sure taxes were not evaded.
So now you know a little bit more about what hops are, how they’re used in beer, and why they’re so important to the flavor of beer and to the taxman. Good old hops from the ground will be around for a while although brewers and scientists have been toying with synthetics, modified hop products, and other novel processes to provide balance and drinkability. New cultivars are still being grown giving the slinking wolf an ever-expanding impressively rich flavor and aroma vocabulary to continue spinning the tale of ale and beer.