What the Heck is Nitro?

What the Heck is Nitro?

Groennfell Meadery
5 minute read

Old Wayfarer on Nitro - Groennfell Meadery

We are inordinately proud of the fact that we now have nitro taps for our mead.

In fact, we are one of the first – if not the​ first – place on earth to have designated nitro taps for mead.

This fact, of course, raises the question… “What is nitro and why should I care?”[1]

The shortest answer: If you’ve ever seen a Guinness poured from a tap, you’ve seen a nitro system.

Guinness Draught

Y’know the tiny characteristic, cascading bubbles? That’s Nitro.

Now, as usual, for the long answer:

Nitro is short for “nitrogen gas system.” This, however, is a bit of a misnomer since a pure nitrogen gas system is used for dispensing wine and other still products. Nitrogen gas (N2) doesn’t  readily dissolve into liquids which means that it can be used as an inert plunger to press on the top of a product to push it up and out of a tap. This is in contrast to, say, CO2 which dissolves into solution forming the bubbles we know and love in craft mead, beer, champagne, and so on.[2]

What a nitro system is, more accurately, is a blend known as “beer gas” which is roughly 75% N2 and 25% CO2. In a nitro system, beer gas is pushed into kegs at approximately four times the pressure of a standard tap system, then the beverage is driven through a special type of tap known as a “creamer,” “stout,” or “nitro” faucet which has a restrictor plate in it to keep the pressure from blowing the glass right out of the bartender’s hand and/or showering the entire establishment with foam. This restrictor plate is about the size of a penny and has tiny little holes in it to slow down the flow of the beer and to force the bubbles into a certain diameter for dispensing.

The question is, why would you go through all of that effort if nitrogen basically comes rushing out of solution the second you pour it? To answer that, we need to visit British pubs in the days of yore.

Back in the days before mass produced beer, almost all beer brewed in Britain was a) locally made if not actually made on premises, b) an ale, and c) consumed very quickly.

When the ale completed its fermentation (or shortly before), the barrel would be bunged closed, placed in a cellar below the main serving area (the bar), and attached to a serving mechanism known as a beer engine. A beer engine is a sort of pump which draws the beer up through the line with approximately 35 pounds of pressure (liquids are heavy), and dispenses it in your glass. Downstairs, one of two things is happening: some of the carbonation is coming out of the beer causing it to go flat, and/or a small amount of air is pulled into the barrel to displace the lost liquid. In the latter case, this air contains lots of chemicals, but the two that matter here are oxygen and nitrogen.

Oxygen spoils beer through a process known as oxidizing. Oxidized beer tastes like old, wet cardboard. Nitrogen, as noted above, is inert. If a pub is going through a cask of ale every two to three days, this isn’t a problem since the beer doesn’t have time to oxidize. Most pubs could easily go through beer at that rate. Then something radical happened: people started wanting a variety of beers. The result was that casks were just sitting downstairs too long and they were either spoiling or, thanks to  innovations in keg technology, simply going completely flat. 

One of the techniques used to serve an acceptable beer and combat the “no foam problem” was that bars were filling glasses with 3/4 flat beer and 1/4 super carbonated beer in the hopes that it would be palatable to their customers. Then, after a few days, the super carbonated beer would become the flat beer and another keg would be swapped onto the flat tap, and so on.

Around the world, people were solving the problem in lots of innovative ways, and our modern draft system is the result. At Guinness, however, a man named Michael Ash figured out a solution which relied on one of the most abundant compounds on earth: Nitrogen.

When nitro was invented, the reviews were… mixed. It fundamentally changed the flavor and texture of Guinness. It made it smoother, but also masked many of the flavors. To this day, in fact, the exact mechanism known as flavor suppression in nitro beers is poorly understood. 

What this means for a mead is that something like Fenberry Draught or Nordic Farmhouse (both cranberry meads) becomes “mellower” when served on nitro. The strong acidic bite of the fruit and the wild fermentation are suppressed by the creaminess of the pour. The result is a mead which tastes something like a pie without any cloying sweetness.

When you take something like Chaos Cyser, our apple vanilla mead, the result is basically a cake you can drink.

So, it appears that the entire article was as simple as saying:
“Why should you care about mead on nitro? Because, basically, we are now serving cake in a glass.”

For more on Michael Ash and his work at Guinness, please check out this article.

[1] It does not “beg the question” since that is a technical term for a type of logical fallacy. The thing about begging the question is that it happens every time you do so.
[2] We are aware that, technically, “Champagne” should be capitalized, but then again, so should “Cheddar.” 

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