NITRO BEER:
It’ s All in the Pour
BY CHRIS KELLER
Years ago while I was working for Saint Arnold Brewery in Houston, I came to work to find several brewers and packaging hands standing around a large stainless steel contraption. It was a tower that had a horizontal boom-like arm with an Liquid Crystal Display control panel and wouldn’ t look out of place in some mad scientist’ s lab. A couple of the packaging hands were playing with a few drops of liquid nitrogen on the concrete floor. After a few jokes about it being a James Bond villain doomsday device, they fessed up that it was a liquid nitrogen dosing machine for packaging nitro beer. Up until a few years before, the only method for packaging nitro beers was in cans with a pressurized ball of nitrogen commonly called a“ widget.” I’ m sure many of you have seen the Guinness Draught or Boddingtons can that rattles and makes a“ pssshhh” sound when you open it. That sound is nitrogen escaping the widget through a small hole into the beer, thus nitrogenating it. You then pour the beer into the glass and watch as the nitrogen bubbles cascade through the beer becoming a creamy head at the top. This machine was the newest method which dosed liquid nitrogen directly into the bottles just before being capped. Under pressure the nitrogen dissolves into the beer only to be released when the bottle is opened and rigorously poured into a glass. The manufacturer of the device had lent us one to test out for two weeks. We were going to nitro a bunch of beer for science!
I’ m sure most of you have had or seen a nitro beer. Guinness is the most popular of all of them, and rightly so. They invented it! Nitro beer has a much creamier texture and mouthfeel. It has almost no carbonation and instead is saturated with nitrogen. Nitrogen will only stay dissolved in the beer while under pressure. Once the beer is out of a pressurized environment, either by leaving the keg or opening the can or bottle, the nitrogen leaves the beer by turning into tiny bubbles all at once creating that cascading effect. The only reason that nitrogen is there is to create the whip cream like foam at the top of the beer.
You might ask why anyone would go through the effort and expense to use nitrogen gas, which makes up 78 % of the air we breathe but has nothing to do with beer, just to make a creamy foam? Nitro beer is actually meant to recreate the flavor of another creamy-head pouring style very popular in English pubs: cask conditioned ale poured through a hand pump called a“ beer engine.” Cask ale is the traditional way beer has been enjoyed in Britain for centuries. Breweries would fill barrel-like kegs called firkins with fresh unfiltered beer along with a little sugar and some extra hops. The firkins would then be delivered to the pubs where the publicans would keep the firkins in the cellar to“ condition.” During this conditioning the live yeast in the beer will eat the sugar and carbonate the beer. Once conditioned the publican then vents the firkin and connects the firkin to a hose attached to a hand pump upstairs at the bar. This hand pump then fills imperial pints from the bottom of the glass forcing the beer through a perforated nozzle called a sparkler. The sparkler removes the carbonation in the beer creating a similar cascading effect and producing a creamy head. The one issue with this style of pour is that the firkin is vented to the air and will oxidize and sour after a few days. As Guinness was closing in on its 200th anniversary in the 1950s, they had outgrown their ability to monitor the pouring of their cask ale. At that time to improve consistency they mandated that each pint of Guinness be poured from two separate casks, one fresh and one older. This complicated process not only took a busy bartender a long time to pour each pint but it made consistency all but impossible. Guinness had their eyes on a global market and this slow and difficult serving process needed streamlining in order to move forward. They called this the“ Draught Problem” and in 1955 they assigned their mathematician Michael Ash to head a team to fix it. Four years later Guinness implemented his nitrogenated beer system that changed Guinness forever.
The choice of a mathematician is no surprise. If a brewer wants to make beer that tastes the same every batch, it takes math to do it. Michael was looking for a way to mimic the flavor of a properly poured Guinness without risking spoilage from oxidation. At the same time he wanted to make the pour an easier, more consistent process. Nitrogen gas wound up be-
28 Jacksonville Progress | Spring 2025