Iron Hill Brewery's "Kaffa IPA" made with Ethiopia-Gera coffee beans

At Iron Hill Brewery, brewmaster Paul Rutherford walks us through the brewing process, where they strive to uphold the principle that “beer tastes best when it’s made fresh.” From start to finish, their tasty beverages travel less than 65 feet.

Paul explains that factors as simple as hard water affect the taste of beer, and at the brewery, they mimic different flavor profiles from regions all over the world by adding or reducing salt content. Water, yeast, hops and malt are the four main ingredients in all beer, but usually only one drives the expressive flavor in an individual brew. For example, “IPAs are driven by hops, but Belgian beers are driven by yeast.” In Iron Hill’s Kaffa IPA, they used our Ethiopian beans to produce a fruity, fresh tasting beer. The brewing process differs from the coffee roasting process in that the source of the beans is the main factor that contributes to the uniqueness of each bean, although both roasting and brewing involve manipulation to produce the final result.

Brewmaster Paul tasting the Kaffa IPAat Iron Hill Brewery Chestnut Hill

Grains start out at the mill, and are roasted just like coffee. “All the different grains start out as the same plant. It’s the length and temperature of the kiln that determines the taste and flavors.”

After the milling process, the grains are moved to the feed auger, and hot water is introduced to form the “mash.” This is the process that converts grain starch to sugars. Hot water passes through the grains, removing all sugars during the lautering process, and the solution (wort) is extracted from the mash and sent into the kettle.

Now, the solution boils for about an hour and a half, and hops is added for bitterness and aroma, which is another big part of what makes each beer unique. The temperature is cooled for the appropriate yeast to ferment, and when making Kaffa IPA, our Ethiopia-Gera beans are added. Paul didn’t want to add the beans when the solution was still hot because it gave a “green pepper flavor,” so it is always added in on the cold side.

“We added the Ethiopian whole beans after the hop addition, and let them sit for three days. It’s really easy to over-do, and the beer can become very bitter if it’s left in too long.” IPAs are a little bit fruity with a lot of body, so according to our head roaster, Chris Miller, “Ethiopian beans were a good compliment because they added a little bit of fruit and a little bit of acid to the flavor, which made the combination fresh and kind of bright.”

Wort is transferred to the fermentation tank, and yeast is added. Active fermentation takes 14 – 30 days, and the “yeast is the boss.” According to Rutherford, they “make a meal for the yeast and hope it gives us what we want.” He says that they want the yeast “happy” because it is actually a living thing, and it can be used up to fifteen generations, so in a sense, it is reusable depending on the type of brew.

Filtering is used to make beer “pretty.” It takes the yeast out so there aren’t any particles left floating around in the final product. “It goes in cloudy, and comes out bright.”

The carbonation level is adjusted in the last step, and it’s now ready for consumption!