Nitrogen Tap Systems

Over this summer, Dangerous Man has installed a nitrogen tap to continue to diversify it’s beer lineups. We’ve noticed a trend on people asking, “what does nitro mean,” “what does nitro do to a beer,””what’s the difference between a ‘nitro’ beer and a ‘regular’ beer?”

We thought we’d take the time to explain some of the nuances of Nitro beer, so let’s delve in.

Nitro Taps

Nitro Taps

As with a lot of beer history and style expectations, the nitro styling has origins in the United Kingdom. Before stainless steel, or other metals were used for holding beer, beer was held in wooden casks. Carbonation happened from a mixture of pulling the beer before it was fully fermented into the cask, ‘krausening’ old beer with young beer and then transferring into the cask, or adding sugar and fresh yeast to each cask. The wooden casks themselves could not hold the pressure for long periods of time, so they were usually drunk quickly, young, and flat. These beers would have a softer, less carbonated feel from the casks lack of ability to hold pressure and to some it became intrinsic to the style of British, Scottish, and Irish beer. To this day organizations such as CAMRA, the Campaign for Real Ales, rally for fresh cask beer in the old stylings that were displaced by the Pilsner takeover after World War II. Beer pushed by Nitrogen and carbonated with Nitrogen/Carbon Dioxide mixtures can be included in the CAMRA organizations styles of serving that hinder the old cask way.

Nitrogen stepped in with the advent of steel for the brewing, fermentation, and storage of beer. Pubs in the Old World mostly had un-refridgerated beer storage allowing for the re-fermentation necessary for carbonation and because refrigeration was costly without electricity. These pubs and bars began to utilize refrigerators and coolers and began the new products that could be used in them. This meant steel kegs that were either naturally carbonated or force carbonated above the previously-used cask levels, which could not keep a pressure for a long time. Customers noticed a difference in the carbonation levels and how it affected the beers they were familiar with. Some for the positive, some not so much. Nitrogen “carbonation” was then introduced to imitate the Old World style and presentation of beer as casks made their way out of popularity.

Nitrogen is insoluble in beer thus making it useful for long and high pressure gas lines because it won’t further carbonate the beer. There’s a lot more at play with Nitrogen than people would normally suspect even though it has become tagged as the name for Nitrogen ‘styles’ of beer. Nitrogen taps are usually a mixture of 70% Nitrogen and 30% CO2, or the “Guinness Blend” which is the proprietary mixture of 75% Nitrogen and 25% CO2. This allows the beer to be carbonated, if being carbonated on that system, at a slower and lesser rate leaving it under-carbonated if it was to be poured on a regular tap. The Nitrogen is then used to push the beer without adding further carbonation out of a special tap that has a restrictor plate. This restrictor plate breaks the CO2 out of solution causing the the spectacular cascade of bubbles which helps to distinguish a “Nitro” beer. By having Nitrogen in the solution it also makes sure that the restrictor plate doesn’t turn the whole beer in just foam, as a regular CO2 carbonated beer would be want to do.

When poured, a Nitro beer has a thick, foamy head with CO2 bubbles cascading both down and upwards in a weird sense. Upon tasting the beer, you’ll notice a thicker and creamier feel that emphasizes the malt character in beer. This is usually the reason why stouts and porters, the more malty styles of ale, are pushed through Nitro taps when available. It’s becoming popular for different styles of beer, especially American IPA’s and Double IPA’s, to find their way into Nitro beer tap lines, though IPA’s have been served over in the UK on Nitro for quite some time. The restrictor plate seems to force out the more volatile hop aromas leaving a maltier nose to an otherwise very hopped beer. Bitterness is left intact though and it definitely creates a striking contrast from the smooth, creamy body provided by the restrictor plate.

Nitrogen taps are gaining in popularity in the United States. Before they were left mostly to American restaurants serving Guinness and other imported UK beers, but with the American fervor for innovation using old and in-place techniques. At any given brewery a nitro tap could spring up featuring one of it’s flagship beers and will be able to serve it in a different way.

Dangerous Man has a dedicated rotation for our Nitro tap. Pretty much any and all beers that we brew can be sent down into the cellar for the Nitrogen/CO2 mixed carbonation and often are. Over the past summer we’ve featured many IPAs, some Cream Ales, our Red Rooibos, even the Belgian Golden Strong, and the Titan of all our titans, the Chocolate Milk Stout. Typically there will be one keg of each style and will be poured until it’s gone. Each lasts about a week, typically, so make sure to check out our website to see what we have on tap each night!