Delivering high levels of fresh hop flavor and hop aroma are calling cards for U.S. craft brewers, but it’s a tradition long loved in many parts of the world. Germans for instance have long been great pioneers in the use of hops and beer. Germans claim hop gardens dating back to the second half of the ninth century, but commercial hop cultivation happened in northern Germany first around the 11th or 12th century, feeding the breweries of the Hansa trading towns, which were exporting hopped beer from probably the 13th century onward.
Today, many German brewhouse brands are still the global benchmark for quality brewing, as well as innovative hopping equipment. When Tröegs Brewing Co. wanted to upgrade its new brewery in Hershey, Pa., a few years ago, the company turned to BrauKon (based in Truchtlaching, Germany) to install a five vessel, 100-barrel (bbl) brewhouse and a three-vessel pilot system with 17-bbl capacity in the company’s new brewery. But BrauKon didn’t stop there. The company also created something unique to Tröegs’ brewing process — the dynamic dry hopping machine called the HopGun. While the HopGun is German in origin, its name is all American.
“We created the name after a nice and easy after-work beer in our brewery [in Germany], drinking our Camba IPA,” explained Andreas Wagner, sales manager with BrauKon. “We were just joking around with different names for our new innovation. This name basically came up, thinking about its design and talking about movies — like Top Gun — which is a popular movie in Germany. We felt the name HopGun expressed the purpose of the equipment best, infusing beer with hop substances most efficiently and quickly.”
Tröegs Brewing’s HopGun has been inducted into Craft Brewing Business’s new series — Innovative Hopping Equipment — our little hall of fame for hopping equipment, techniques and production. Here’s a breakdown of the mechanics and theories behind this innovative hopping gizmo and other unique hop insights from these famous brands in craft brewing.
How does it work?
First off, the HopGun is aimed at not only adding hop flavor and aroma to beer, but conserving expensive hop usage. Hops are first poured through a large man-way on top of the HopGun (after the system has been completely sterilized from previous usage). “With the use of the cellar beer pump, in a perfect world equipped with a frequency drive, we pump beer into the HopGun and out again either back into the same tank [recirculation] or into another tank,” said Wagner. The shape of the HopGun and the different inlets create a vortex in the vessel, leading to an intense and efficient contact between the beer and the hops, which facilities quick dissolving in a short amount of time.
“In the middle of the HopGun, we have a special engineered candle, not allowing the whole hop pellets to just get flushed back into the tank,” said Wagner. “This candle also guarantees a high process standard and reproducibility. While the whole dissolving process is taking place, we also have the possibility of switching to different inlets to use the HopGun like a hydro-cyclone, allowing us to strain out some of the solids which did not get dissolved.”
BrauKon claims to save up to 30 percent on the amount of hops regularly used by craft brewers. “The aroma profile we are finding in our beers improved but with less process time and connected work,” said Wagner. Depending on the used hop varieties, dissolving times are between one and two hours (but it depends on the tank geometrics).
“In a master thesis we did with the university of applied science of Regensburg [Germany], we found that most of the cold extraction is taking place in the first two hours,” explained Wagner. “With this said, we recommend to recirculate the tank volume through the HopGun once an hour. This should help homogenize the tank with the dissolved hop ingredients.”
BrauKon is definitely interested in working with other brewhouses when it comes to the HopGun. The unit at Tröegs can carry 220 pounds of hop pellets for one charge. The design is engineered with stainless steel side walls and observation side glasses built in. To use the HopGun, brewers need a cellar beer pump (preferably frequency driven), some hoses and if you want to recirculate with one tank, a second inlet or double outlets (think racking arm). ”Due to its size, you might need a small platform to fill the HopGun — it is filled from the top,” said Wagner.
The Eureka! moment
The HopGun is unique in America to Tröegs Brewing right now, but BrauKon actually invented it for the brewery it runs in Truchtlaching, called Camba Bavaria. Friedrich Banke, developing engineer and shareholder of BrauKon, and Markus Langer, project manager at BrauKon, came up with the idea when they were considering the problems of consistency with dry hopped beer and also the huge amounts of hops used from which the aroma is pulled.
“Our company is known for building high-quality breweries with all our unique and sophisticated technologies for pre-mashing, mixing, boiling, etc.” said Wagner. “The focus of our brewhouse technologies is starting from an efficiency prospect and leading especially to the beer quality, so we had to find a solution for dry hopping too.”
The biggest trial and error for the HopGun was finding the correct hop amounts for the beer. The company started by using the same amounts used before for dry hopping. “The beer we got was extremely piney, oily and sticking in your mouth for a long time, which I thought was great, but not the beer we had before,” said Wagner. “We had to cut back weights and that led to an extremely interesting experience to see how flavor profiles changed.”
What beers are brewed?
Right now, the HopGun has only been used by Tröegs to make its Triple Dry-Hopped Perpetual IPA, as well as some other test batches, but Tröegs just bought another bigger unit, which it hopes to install by early next year. Owner John Trogner describes the distinction in flavor using the HopGun: “The aroma and flavor is out of this world. It’s a completely different type of aroma. It’s hard to explain but it’s softer on the pallet and cleaner in flavor and aroma.”
A small but interesting side note: BrauKon is currently working on different candles for the HopGun. “We see a great use also in extracting spices and all other aromas of the world and infusing them into the beers,” explained Wagner. “We did some trials already with coffee beans and a regular stout and found a wonderful coffee stout after two hours of contact time. With the different behavior of the spices, we are doing a lot more tests and trying to keep the spices from going into the fermentation vessel.” We’ll keep you updated on BrauKon’s progress.