It’s been a quiet trend in Kiwi craft beer bars over the past year – the smooth, cool pour of the nitrogen tap.
Nitro taps fit somewhere between the traditional CO2 taps and handpulls. Like the CO2 taps, beer is dispensed cold, by pressurised gas. Like the handpull with a sparkler, nitro-poured beers have a rich head and smooth mouthfeel. They lack the sharper CO2 effervescence, and flavour profiles are skewed away from hops and towards darker malts.
Christchurch’s Volstead Trading Co. has been running a nitro tap since last winter. Manager Caitlin Brown says the single nitro tap links Volstead’s nine handpulls and 13 CO2 taps.
“The nitro tap introduces people to hand pulls, because the beer’s served cold but it has the feel of a handpull. It’s always a big seller for us, gets good feedback.”
Caitlin says Volstead has run many brewers’ beers through its nitro tap – stouts, porters, black IPAs and bitters. “We’ve currently got the Nitro Rye IPA from Good George, and it’s just pouring beautifully.”
Caitlin finds the nitro pour produces unique flavours. “We’ve had the same beers on the handpull and on the nitrogen tap so we can see the difference. For educational purposes that’s been really cool, for staff and customers.”
Weezledog brewer Mark Jackman says he literally grew up on nitro beers in his native Yorkshire. “I do appreciate a good nitro beer. I wouldn’t say it was as good as a handpull, but if beers are a bit rough around the edges it can smooth it out and give it a nice creaminess. We haven’t done any of our beers on nitro but I’d love to try Dickledoi Imperial Ruby Ale on it.”
Fellow Englishman Geoff Griggs believes nitro is no replacement for a handpull. “I most definitely do not see nitro as a substitute for handpulls - even those specifically designed to dispense Northern English style beers, i.e., handpumps fitted with swan necks and sparklers.
“While I will concede some stouts and porters can be successfully dispensed by nitro - in which case the hop aroma, roast astringency and bitterness seem to be softened (which is fine if that's how you like your beer) - I have yet to find another style of beer which in my view isn't compromised by nitro dispense. And as for modern, hop-forward IPAs being dispensed on nitro, don't get me started!”
Eagle Brewing’s Dave Gaughan is another Englishman who experienced nitro and handpulls before coming to New Zealand. His brewery is next door to Volstead, where Eagle ales have been served on the nitro tap.
“Nitro brings out the malt character in beer and deadens the hop flavour. It does English bitters very well, stouts, Red IPAs very well, because they are malt-based beers. We have tried Big Yank but it doesn’t do those hoppier styles justice.
“Compared to a handpump, nitro is probably a second rate substitute, that’s my view. It’s a temperature thing. You get the texture and creaminess but you lose flavour because of the colder serving temperature. From the brewer’s point of a view, it’s a pain in the arse to produce because you are working at a lot higher pressure.”
Those higher pressures are needed because nitrogen is much less soluble than carbon dioxide. That’s why nitro beers are smoother than the same beer served on CO2 – that smoothness is because the nitrogen leaves the liquid as fast as it can, producing a rich head but no long-lasting bubbles (as from carbonation).
The US craft beer scene has adopted nitro pouring, and, as usual, taken things a step further and experimented with hoppier beer styles. A 2013 poll of Craftbeer.com readers showed 60% “loved” nitro beers and just 4% “don’t like them and avoid them”.
The Good George Rye IPA pouring at Volstead is a local example of the hoppier styles that are now showing up on nitro taps. Good George brewing director Brian Watson says he’s been watching nitro’s popularity grow in the States, and the Rye IPA was inspired by a recent industry event he attended in Las Vegas, where “there were ten craft beers on tap, and six of those were nitro.”
“It’s quite different to hand pumps. The beer tastes quite different. Nitrogen does absorb flavour compounds and make it softer, where you will get a fuller flavour experience on a handpump,” Brian says.
“The biggest growing category in the US is IPA and nitro IPA a subcategory of that. It’s growing very fast over there. I’m going to the US this week to do a bit of research before judging the World Beer Cup, and if nitro is taking off there we’ll certainly be looking at more of it.”