A lot of beer lovers know that the four main ingredients in beer are water, malted grains, yeast, and hops, but not all of them know that hasn’t always been the case.

Technically speaking, beer only needs to be comprised of water, malted grains, and yeast. In fact, beer was brewed for thousands of years before hops were ever used.

At Agrarian Ales, we grow 100% of the hops used in our beer, so we’ve spent a lot of time thinking about the critical role they play.

Here are a few things about hops that you may not have known.

Bitter Hops Are the Yin to Sweet Malted Grains' Yang

Hops serve a couple of key functions for beer and brewing a tasty beer is all about finding the perfect balance.

The brew day at Agrarian starts off with milling premium organic malt. We choose to mill our malt at the onset of brew day to reduce oxidation and retain maximum malt freshness - just as your favorite bag of Kettle Chips will get stale if left open for too long, each kernel of malt will do the same if it is not milled fresh. This crushed malt is then steeped between 148 - 158 degrees to activate enzymes in the malt to convert starch to maltose (a simple sugar). Maltose is fermentable (i.e. brewer's yeast can eat it and spit out alcohol and CO2) and very sweet. A solution of water, maltose and an indescribable flavor cocktail from all the other soluble organic molecules derived from the various toast and roast levels of malts is separated from the malt husk and collected in the brew kettle. This solution is called wort, and it typically smells of fresh toasted bread and has a distinctly sweet flavor.

This sweetness must be tempered, so hops are added because they have resins and acids which impart bitterness and counterbalance the sweetness of the wort.  

For much of beer’s history, a mixture of spices and herbs called “gruit” were used to achieve this balance before hops became the preferred choice.

Additionally, gruit and hops work as a preservative to keep the beer fresh and safe to drink for longer periods of time.

The Different Ways Hops Are Used in Brewing

In recent years, hops have moved from the supporting cast to the starring role in many styles of beer. The Pacific Northwest is a wonderful place to grow hops and the predominant source for most of the nation's hops.

There are many ways to incorporate hops into beer and each method adds a different quality to the beer.

Alpha acids are the main bittering agents found in hops, but there’s one problem with them: they’re naturally insoluble in water.

To make them soluble, they are added to the boiling wort and the heat causes the alpha acids to be isomerized into their water soluble form. The longer the hops are boiled, the more isomerization that occurs, and the more bitterness that is imparted into the beer.

Bittering Hops

As their name suggests, the purpose of bittering hops is to add isomerized alpha acids to the wort to balance its sweetness. These hops tend to be high in alpha acids and are added at the beginning of the boil.

Flavoring and Aromatic Hops

While boiling hops for longer periods of time adds bitterness, it also destroys the more delicate essential oils that contribute hop flavor and aroma that so many beer lovers look for.

That’s why flavoring hops aren’t added until part way through the boil. This allows enough time for flavorful oils to be added to the wort but not so much time that the oils are altogether destroyed.

The aromatic oils from hops are the most delicate which is why aromatic hops aren’t added to the boil until the last few minutes, or even just after the boil is stopped. These additions impart the bright hop aromas that the hop heads of the world love.

Dry Hopping

Dry hopping can be done in a variety of different ways but all techniques entail adding hops only after the wort has cooled after boiling. Akin to steeping, this allows the volatile flavor and aroma oils from hops to be added without any fear of excess heat destroying them. Originally, this concept was used by sailors as they would add hops to their casks to preserve their beer over long sea-faring voyages.

For maximum effect, and to capture as much of the volatile oils as possible, the process of dry-hopping is best done right near the completion of fermentation. At this point, the vigorous CO2 production during fermentation is complete, so the aroma of the hops won't be scrubbed out of the beer as CO2 is generated and bubbles up and out of the fermenter.

At Agrarian we use a process of dry-hopping referred to the Pendulum Method. Whole cone hops are placed in a separate, smaller vessel and that is purged with CO2. The fermenting tank is then put under pressure, valves are opened, and a portion of the beer flows into this separate dry-hopping vessel. This vessel has a screen it it to keep the hops in place as beer moves in and out. Once the beer sits in the dry-hopping vessel for a certain time then we pressurize it and send it back into the fermenter. We will typically send the beer back and forth upwards of a dozen times before the process is complete.