For Issue 4 (Winter 2014/2015) of Craft Beer & Brewing Magazine™, we talked with Left Hand Brewing Company VP of Brewing Operations, Joe Schiraldi, about their approach to capturing nitro in a bottle.
Craft Beer & Brewing: Why did Left Hand decide to focus so heavily on bottling nitrogenated milk stout?
Left Hand Brewing: We’ve been brewing and serving nitrogenated milk stout since the turn of the millennium. At first, it was served only in our tasting room. The next phase was to make the nitro draft more accessible. Once we were confident we had the correct process control in place, we started sending the beer to draft accounts. At one point in the late 2000s, there was a grassroots uprising from our team members who pushed for us to bottle it. There was very little existing information on how to do this, and the technology was still evolving, so we spent most of our cognitive power for a solid eighteen months trying to solve the problem of how to do it. If you’re interested in learning about something like dry hopping, you could spend a lifetime reading up on it. But that information isn’t available for nitrogenated beers. It took a lot of trial and error, punches in the face, and kicks in the gut to figure it out.
CBB: What is it about the experience of nitrogenated beer that makes it so appealing?
LHB: Cask beer has an extensive history, and nitro is an extension of that. We have a great love for the presentation of it, and the opportunity to push into uncharted territory was appealing. The first beer we nitrogenated was our Milk Stout, and I’ve found the nitro brings out more chocolateness, while the CO2 version brings out more coffee notes. But it’s the same exact wort for the two beers.
CBB: The exact same recipe?
LHB: Yes, the wort is exactly the same. We could pull from the same bright tank and carbonate half while nitrogenating the other half. Having said that, your beer gas is as important a part of your recipe as anything you put into it. Personally, I find that CO2 increases olfactory inputs, while nitrogen brings out more desirable mouthfeel and visual elements. We’ve stuck with releasing less hoppy beers with nitrogen, since CO2 brings out more hop aroma.
CBB: What tips do you have for homebrewers looking to nitrogenate their own beers?
LHB: Experiment with whatever you want to. You’re not beholden to anyone but yourself and your friends. But your first challenge is to figure out your specs and values. The CO2 content (in the gas mix) is critical. With the nitrogen content, you have more wiggle room. The gas mix we use is different for each of our nitrogen beers: Milk Stout, Sawtooth ESB, and Wake Up Dead Imperial Stout. We look at each beer as an individual.
CBB: How much nitrogenated beer do you produce these days?
LHB: It’s by far our biggest growth product. Milk Stout in particular has gone from being about 10 percent of our brewery output in the late 2000s, to 50–55 percent today.
CBB: How will nitrogenated bottles of Wake Up Dead (Russian imperial stout) fare when aged?
LHB: I think a lot of people over-age their imperial stouts, but of course it comes down to personal taste. I have over-aged imperial stouts myself. I feel the beers do not improve infinitely over time—there’s a sweet spot. The aging has to enhance characteristics already in the beer. For my taste, that’s usually about three years max, but it depends on a number of factors. Aging is controlled staling of beer, so factors such as how the bottle was filled can have significant impact. We release Wake Up Dead once it’s ready to drink—it ages about 3–4 months in the brewery, and release time is determined by sensory analysis. We taste it and package it once it’s ready.