Perhaps you’ve heard Jim Koch — founder of Sam Adams brewery — say in his commercials that Hops are the soul of a beer, that they are for beer what grapes are to a good wine. This is arguable, but the problem with that statement is that not all beers use hops as an ingredient. Additionally, saying that they are to beer what grapes are to wines forgets that the major flavor component of a beer is grain — not hops, just as grapes provide the majority of flavor for wines. Still, all that said, hops really are incredibly important to beer.
A quick search on the almighty Wikipedia reveals interesting minutiae about the flower of what amounts to a vine-like weed. Hops were first mentioned in historical writing by Pliny the Elder; were banned in England until the late 1500s, and so forth. But none of that trivia tells you why they have been used in beer for centuries.
Hop flowers contain small glands that produce Lupulin, a chemical resin that has mild sedative effects on its own — no alcohol required. This is true only of the “female” plant. The resin is made up in part by Alpha and Beta acids. These are the chemicals important to brewing.
Alpha acids isomerize — i.e. molecularly rearrange — when boiled for an hour or so, and have a preservative effect that limits the growth of certain bad tasting bacteria, creating a welcoming environment for brewing yeasts. They also produce a characteristic bitterness but don’t really provide much of the aroma that we associate with beers. The bitterness of a beer is actually measured using a unit called an International Bitterness Unit, or I.B.U.
Beta acids, on the other hand, produce the aroma and flavor that you recognize when you drink a beer like an American IPA. They are typically added after the majority of the boil has been completed — between ten and three minutes left — or after the heat has been turned off — called “knockout.” Beta acids tend to impart a flavor and aroma of overcooked vegetables or cardboard if they are added to the boil too early in the process and allowed to oxidize. Hops added to cooled beer only impart aroma, as none of the Alpha acids are isomerized to produce the bitter taste. Beers with ultra-high Beta acid levels are known to produce a feeling of corrosion on your teeth, but this is really just the hop resin sticking to your enamel.
After years of experimentation, and selective breeding of hop varieties, experienced brewers know which hop varieties high in Alpha acid for bittering and preserving a beer to combine with which high Beta acid flowers in order to create the style of beer they are aiming for.
If you want a classic German beer, you probably use one of the Noble Hops that have been used since the Renaissance to achieve the balanced character that most German beers possess. English ales use more recent cultivars, and many American beers use all manner of mutated, cross-bred varieties to get the insane I.B.U.s we sometimes look for.
Ironically, just as the trend of highly hopped microbrews has taken off in the U.S. and other countries, hop prices have skyrocketed in the past two years, largely owing to increased shipping costs, drought affected harvests, a major fire in an American hop storehouse that destroyed a massive portion of the crop two years ago, and other more nebulous demand issues. On average, the cost of making a batch of homebrewed beer has increased nearly $10. I speak from experience.
The reaction among brewers is mixed. Some have simply changed their style preferences from big, incredibly hoppy ales to more mellow, malt focused lagers. Others have decided to get back to the roots of beer-making by experimenting with traditional bittering agents that haven’t seen much use since the rise of hops as the undisputed king of beer preservation. Some are brewing less often or have just stopped brewing all together.
Spruce tips, used commonly by early American brewers when hop imports were scarce and expensive, have seen resurgence. A good commercial example is Poor Richard’s Tavern Spruce produced by the Yard’s Brewery in Philadelphia as part of their series produced from recipes supposedly developed by the Founding Fathers — this one obviously attributed to, or allegedly enjoyed by legendary beer advocate and awesome lecher, Ben Franklin.
Other brewers are trying out different mixtures of gruit — a mixture of spices formulated to preserve and flavor beers. Historically, gruit was the only way to go in England until the 17th Century. Some typically used gruit components are considered psychoactive — Wormwood for one, the offending component that made absinthe illegal — and in some cases aphrodisiacs. Some historians even believe that the rise of Puritanism was the root cause of England switching from gruit to hops in an attempt to further a relative temperance amongst a population that was swilling down semi-hallucinogenic beverages at an amazing clip. Beer being more potable than most water at the time.
This experimentation is fine, but it doesn’t fully account for the ultimate reasons why hops are so ubiquitously used by brewers: Hopping is a better preservative than any other natural option, and most importantly, hopped beer just plain tastes better to more people.
A bit of British folklore says that during the time when beers were hopped, but not very heavily, a cask of export ale — highly hopped and very alcoholic in order to preserve it for its trip to India via Clipper ship — was smashed open on its way to the docks. Poor dockside residents hurried to the site of the disaster and scooped up what they could in available vessels and noted how good the beer tasted in comparison to the more lightly hopped porters they were used to being served in the taverns. They demanded the brewery provide their taverns with the same stuff the troops occupying India were getting, and thus super hopped beers were born. I suppose there’s no arguing with that kind of popular demand.
Tags: Beer