From grains to growlers, Grumpy Troll’s brewmaster keeps business hopping
“Every weekend is Oktoberfest at the Grumpy Troll,” says Mark Knoebl, brewmaster at the Mount Horeb brewpub. With 12 homemade brews on tap on any given day, Knoebl ensures the beers he makes are the best they can be so customers keep coming back.
“We try to offer the gamut,” he says, “a different balance of beers. For the most part, I developed these beers. Every brewer has their take on different styles. There’s no right or wrong, it’s just intuition and experience.”
His intuition about one beer, Erik the Red, apparently was right on. “When I came here, it was a fine, red beer, but I didn’t really like it, personally,” Knoebl said. “So I tweaked it and went from, like, three ingredients to 12.” For three years in a row, it has been recognized as one of the Midwest’s best in the U.S. Beer Tasting Championships.
Just a hop, skip, and a jump west of Madison, The Grumpy Troll attracts a varied crowd with varied tastes, including aficionados from larger cities, where Knoebl says beers tend to push the taste profile. “We get that crowd, too, so we have to be on the high-end game, but we also need to please the local or rural folks who just come in for a good beer.”
Mash up
The process of making beer at the Grumpy Troll starts in the grain room on the building’s second floor, where 55-pound bags of various barleys from around the world — the Czech Republic, Canada, the United Kingdom, Wisconsin — are stacked around the hopper, a metal chute cut into the floor.
“A lot of breweries are designed vertically because of gravity,” Knoebl explains, “and barley dust is very harmful to beer because its natural bacteria can spoil beer. You want to keep the dust away from the tanks and vessels where the beer ferments.”
The grain is poured down the chute (left) into the 10-barrel brewhouse on the main level of the establishment. It travels along a conveyor and is dropped into a mash tun filled with 155-degree water where, over the course of an hour, the starchy grains become sweet and sugary. The liquid filters through the grain to the bottom of the tank and eventually goes into a brew kettle where it is boiled for about an hour and a half.
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“These days, young kids coming out of college are used to craft beers. When I was in school, we wouldn’t drink the stuff.” — Mark Knoebl, brewmaster, The Grumpy Troll |
Knoebl manually empties the “spent grain” into buckets that will later get picked up by a local farmer who uses it to feed his cattle and a local woman who feeds it to her heritage pigs.
In the Grumpy Troll’s basement, a freezer is stuffed with bags of fresh and pelletized hops. Knoebl uses the pelletized variety most often. “Whole-leaf hops pack a more aromatic punch, but they quickly oxidize, and oxidation is bad for beer.”
At different points in the boiling process, hops are added for flavor and aroma, giving each beer its unique taste. If added early in the boil, they add bitterness; if added in the middle, they add flavor, and at the end of the boil, aroma.
The boiled brew, or “wort,” is cooled with a heat exchanger and moved into one of six large fermenting tanks where yeast is introduced. The type of yeast used dictates the rest of a beer’s recipe. More barley means more sugars. As the liquid ferments, the yeast eats the sugars, producing CO2 and alcohol. “If there’s more grain, it will be a stronger beer, and less grain, a lighter beer.” Fermenting time depends on the specific beer being produced.
The beer Knoebl is making this day has a 9% alcohol content. Another tank contains a bock beer that will be introduced later this fall. When the liquids settle, Knoebl will collect the yeast that falls to the bottom of the tank and reuse it for another batch. “We might reuse yeast two to six times until the yeast is done,” he notes.
Knoebl turns a nozzle on two tanks to release gas that has been produced during fermentation, resulting in a loud hiss. Then he leaves the brewhouse, closing the door behind him. “You can’t breathe that air,” he cautions.
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When fermentation is complete, the beer is transferred into any of five 300-gallon serving tanks in the basement. It takes about 50 minutes to carbonate a tank of beer, at which point the beer gets hooked directly up to the tap in the upstairs bar. Usually, Knoebl brews two 300-gallon batches every week to keep up with demand. Between 300 and 500 gallons of beer are consumed each weekend.
Of the dozen beers the Grumpy Troll keeps on tap, a third contain about 5% alcohol, another third run between 5% and 6%, and then there’s the top tier for those who prefer stronger beer. A&J Anniversary Ale, named after the business’s owners, has an alcohol content of 9.8%. Six of the Grumpy Troll’s beers are available year-round, with the others rotated in and out seasonally “to change it up,” Knoebl says.
Clean up
When he isn’t tending to his beer, Knoebl spends about 80% of his time cleaning. “Cleanliness is the biggest thing,” he says. Tanks are purged with CO2, and Knoebl sprays his hands and all hose connections with rubbing alcohol anytime they are handled. “We clean constantly,” he says. “Beer isn’t affected by sitting in a tank. What affects beer taste is a dirty tank, or sunlight, or oxygen and bacteria.
“Our beer is unpasteurized. It’s a natural product. It might be a little cloudy in the beginning, but then it settles down. From the beginning to the end of a batch, there is some variation. It’s kind of cool.”
Knoebl, 50, a graduate of the Siebel Institute of Technology, America’s oldest brewing school, has been a home brewer most of his life. He’s worked for the Grumpy Troll for four years but has been in the industry for 20, including four years at New Glarus Brewery, where he says he “cut his teeth.”
Taste buds have changed over that time, he notes, and now most beer drinkers favor quality over quantity. “These days, young kids coming out of college are used to craft beers. When I was in school, we wouldn’t drink the stuff.”
Other tastes are changing as well: “Twenty years ago, IPAs weren’t the hot item. Now they are. In four to five years, it could be all about sour beers.”
A whiskey barrel in the Grumpy Troll’s basement that had been used to age an imperial stout now holds a concoction of sour beer that will naturally ferment for about a year. “We do [sour beer] on a very limited basis to keep our finger in the pie,” Knoebl says.
The Grumpy Troll produces about 500 barrels of beer each year, as well as its own root beer. Several beer varieties are hand-bottled and sold as 22-ounce souvenirs. Growlers, or 64-ounce take-along containers, are also available. “It’s nice that if you want my beer, you have to come here to get it,” Knoebl says. “If I put the quality in, people appreciate it and keep coming back. It’s a reflection of my work.
“But we make as much beer here as what New Glarus can spill in a month, or Budweiser can spill in a day.”
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