Not so long ago a war was brewing in the world of beer. Scotland's BrewDog and Germany's Schorschbräu were locked in a battle over booze, each one vying to have the world's strongest beer.

BrewDog fired first with a 32 percent alcohol stout called Tactical Nuclear Penguin. The beer's release was announced with a video featuring the brewers in penguin suits. Schorschbräu retaliated with the 40 percent Schorschbock 40. This skirmish escalated; Sink the Bismarck at 41 percent followed by a 43 percent Schorschbock. Finally BrewDog delivered a seemingly decisive blow with the End of History, a super-potent brew that topped a whopping 55 percent.

But the conflict wasn't quite finished. The final shot came from an unexpected source when Belgian brewery 'T Koelschip announced Start the Future, the current record holder at 60 percent alcohol. And so it goes in the world of extreme beer.

These super-high-test beers are made using a distillation process called "icing," in which an already high-alcohol beer is frozen until water crystals form. The unfrozen portion is then run off. Because water freezes at a lower temperature than does alcohol, the resulting product is a concentrated form of the original.

BrewDog's Tactical Nuclear Penguin and Sink the Bismarck recently saw extremely limited availability in the Twin Cities. Sink the Bismarck is everything one would expect when booziness is the brewer's primary aim. It reminded me of German salted licorice dissolved in Pine-Sol, finishing with an especially unpleasant and long-lingering bitterness.

Almost two decades

The grandfather of extreme beers is Boston Beer Co., makers of Sam Adams. In 1994 they released the first vintage of Triple Bock, a 15 percent ale brewed with maple syrup that was one of the first beers to be aged in whiskey barrels. Only three vintages were made -- 1994, 1995 and 1997 -- but bottles still occasionally turn up in stores.

If properly stored, these high-alcohol beers age like fine wine or whiskey. After 17 years, Triple Bock has become an intensely complex sipper. It pours thick and black from its blue-glass bottle, without even a hint of carbonation. The flavor is candied cherries smothered in rich dark chocolate. Background notes of soy sauce, sherry, maple and vanilla add intriguing depth. Though not for everyone, many will find Triple Bock a richly satisfying treat.

Weighing in at 27 percent alcohol, Samuel Adams Utopias remains the strongest naturally fermented beer ever made. Utopias is not so much brewed as constructed. It is a blend of beers from different vintages dating back to the original 1994 batch of Triple Bock. Some of these component beers have been aging in bourbon, brandy, sherry or cognac barrels for 17 years.

More like cognac or port than beer, Utopias is uncarbonated and meant to be sipped at room temperature. Alluring aromas of butterscotch and maple greet your nose as soon as the liquid falls into a glass. Those aromas carry over into the flavor, where they are joined by background notes of chocolate, tart cherries and caramelized prunes. The hefty alcohol tingles the tongue and warms all the way down. Utopias makes a great aperitif.

The 2011 vintage of Utopias was released a couple months back. Bottles can still be found in area stores, but you'll have to ask for it. A 22-ounce bottle will set you back about $180.

Michael Agnew is a certified cicerone (beer-world version of sommelier) and owner of A Perfect Pint. He conducts private and corporate beer tasting events in the Twin Cities, and can be reached at michael@aperfectpint.net.