My latest Beer 101 came out, like, a month ago (in fact the next one is due in a few days). How is it I keep forgetting to post about it? I need some kind of alarm cl0ck for beer columns.
At any rate, August’s Beer 101 continued my examination of gas in beer (as opposed to gas from beer). I take a look at the rarely discussed nitrogen. Most have no idea that some beer have nitrogen in them. Fewer understand why. So, it seems a good topic, eh? I work through the science a little bit and explain how that funky, bizarre “Widget” found in cans of Guinness works. The Widget really is one of the coolest beer inventions of the past 50 years. I guess the big boys are good for something.
That is all pretty fascinating stuff – I rather enjoyed researching that particular column – but for most of you the most important issue is how nitrogen affects the flavour and presentation of the beer. Well, to satisfy that curiousity, here is a quote from the column:
Nitrogen is less acidic and much softer than carbon dioxide, which, if it is mixed into the gas line, can have profound flavour effects. The biggest thing it does is smooth out the body and round rough edges of the beer. Sweet is also accented more, as are malt-based flavours and aromas. A beer seems fuller and more earthy. … They are softer, more blended and silkier. They also have a tighter head and smaller bubbles.
I remember before the days of the Widget noticing how much less appetizing Guinness in the bottle was compared to on tap. Plus Kilkenny goes down dangerously easy for me. In both cases, that is the nitrogen talking. Nitrogen isn’t easy to work with, which is why most breweries and almost all homebrewers (that I know) avoid it. However, the benefits are pretty striking.
So, give the the column a read here and learn a little bit about the other beer gas.
And note there is a typo in the column. Not a big deal but significant. At one point I say “…but mix it with 30% oxygen…” but I meant “carbon dioxide”. I make it clear earlier in the column that beer gas is 70% nitrogen/30% carbon dioxide, but obviously my fingers like the idea of instantly oxidizing your beer (which is what would happen if there was 30% oxygen in the line). I mention it just to prevent the inevitable “you got it wrong” emails.
September 16, 2011 at 11:09 PM
My understanding, however, is that nitrogen will ruin the hop profile of beer. This hop reduction is not an issue for most stouts, but it is death of good pale ales.
September 16, 2011 at 11:48 PM
Steve,
A good point. One that I have heard too, but didn’t find a way to mention in the column. There is a reason why stouts and Irish reds are the beer of choice for nitrogen.
Thanks for highlighting it.
September 17, 2011 at 5:42 PM
A bar I used to frequent in Toronto used to have a nitrogen blanket on their cask ales…..and for me, it totally ruined every pint. It was like drinking beer with tiny tiny granules added. An added bonus was the typical nitro headache the next day.
Back in the day I tried to figure out why Kilkenny would give me a bad head after 3 or 4 cans; all along it was the nitro in the can/tap line.
I now steer well clear of nitro beers.
September 18, 2011 at 11:12 AM
A nitrogen blanket isn’t going to dissolve any nitrogen into the beer. To serve as a relative point, carbon dioxide will dissolve over 100 times as easily nitrogen in water around 0C. The blanket is very near atmospheric pressure and the nitrogen will not dissolve into the beer. It would require immense pressures to push it into the beer. This is especially true if the beer is just under a head pressure of nitrogen and it is not being forced into the beer via a ‘nitrogenation’ stone or shaking of some sort.
September 18, 2011 at 11:23 AM
@Chase, there was nitrogen in the cask ale. Even the way it poured you could tell there was nitrogen “introduced” to the beer. Every pint, no matter the style, had a head that a pint of Guinness would be proud of!!
September 20, 2011 at 3:31 PM
@Sid and Chase. I don’t know that much about cask engineering, but if the nitrogen blanket was sparged, wouldn’t that work (I’m thinking that it would work like a widget)? I guess even a sparkler on the end of the tap would do the same: You don’t have to dissolve the nitrogen, right? You just need to violently mix the liquid and the gas in order to get that creamy head.
@BG. I could have some details of large-scale brewing mixed up (and I’m far from an expert in these matters), but I don’t think that the main difficulty with nitrogen has to do with the relative abundances of CO2 and N2 in the atmosphere, as you say in your 101 article. It has more to do with the relative solubilities of the different gasses. At about 2bar pressure (Zhang&Xu 2008; Elements v.4 p48; http://dx.doi.org/10.2113/GSELEMENTS.4.1.47), N2 has 1/65 the solubility of CO2, so in order to dissolve an equivalent volume of N2 you need unreasonably high pressures as @Chase mentioned. I could be missing something, though.
September 21, 2011 at 1:33 PM
Nitrogen ruins the aroma. And while it creates a creamy mouthfeel at the start of a pint, by the time you get halfway through, the beer becomes a lifeless, watery mess.
I don’t like nitrogen.