Nitro Beer Not What I Expected

[hopjunkie26]

So a while back, on a whim, I decided that I was going to convert one of my taps on my kegerator into a nitro tap. Got everything installed, lines ran, beer gas tank, regulator, everything.

So I hooked up a Pumpkin Stout that I already had on hand and was, at a minimum, partially carbonated on CO2. Let it sit for a week or so and poured a pint. I got the cascading effect from the nitro and good head to the beer, but the head wasn't thick like you would expect from a nitro beer. It dissipated and thinned out very quickly.

I thought it might need a little bit longer but, months later, still same result. Everything tastes fine with the beer (no off flavors or anything) but I just don't get that creamy, thick head on the beer.

Any thoughts? The only thing I can think of is that the beer was already fully carbed on CO2 and that is keeping it from being thick??? Not real sure.

 

[Browningbuck]

just curious which faucet you bought?

 

[motobrewer]

have you made this pumpkin stout before? Does it have a good head on CO2?

 

[hopjunkie26]

Browning, I purchased this faucet:
http://www.ritebrew.com/product-p/843180.htm

Moto, yes I have made the stout in the past and have never had any issues with the head.

 

[stratslinger]

What's your process for pouring a pint like with this thing? At the Guiness storehouse they'll teach you the "proper way" to pour a pint of Guiness, and they swear up and down that that pour is at least partially responsible for the desirable qualities of the head and mouthfeel of the beer.

The other thing that comes to mind, is that shouldn't a beer be fully carbonated before being put on a Nitro tap? I'm almost certain I've read just that before - the Nitro-mix apparently doesn't dissolve into solution like CO2 does.

 

[hopjunkie26]

Funny you mention Guiness, my wife travels to Ireland for work every once and a while and wen to the storehouse to become a certified pourer. I use the exact technique that she was taught over there.

When it comes to carbonation, I am not sure. I have heard that the beer should be fully carbed but I have also heard that it helps to be slightly undercarbed.

Just like everything else with brewing, it seems there are multiple theories behind it. I suppose I could be being a little picky but I know I am not getting near the quality that I would get at a brewery/bar that has a beer on nitro. I order them whenever I can.

I will post a picture later this evening to show what I am experiencing. You can tell just by looking at it that its not quite right.

 

[Browningbuck]

Browning, I purchased this faucet:
http://www.ritebrew.com/product-p/843180.htm

i dont think its hardware as i use the same faucet but in SS and these are the results.

 

[bcrawfo2]

So a while back, on a whim, I decided that I was going to convert one of my taps on my kegerator into a nitro tap. Got everything installed, lines ran, beer gas tank, regulator, everything.



So I hooked up a Pumpkin Stout that I already had on hand and was, at a minimum, partially carbonated on CO2. Let it sit for a week or so and poured a pint. I got the cascading effect from the nitro and good head to the beer, but the head wasn't thick like you would expect from a nitro beer. It dissipated and thinned out very quickly.



I thought it might need a little bit longer but, months later, still same result. Everything tastes fine with the beer (no off flavors or anything) but I just don't get that creamy, thick head on the beer.



Any thoughts? The only thing I can think of is that the beer was already fully carbed on CO2 and that is keeping it from being thick??? Not real sure.

What pressure do you run your beer gas at?

 

[JuanMoore]

Beer temp? Serving pressure? Gas blend?

Any thoughts? The only thing I can think of is that the beer was already fully carbed on CO2 and that is keeping it from being thick??? Not real sure.

Excessive carbonation would result in a foamy mess rather than a nice cascade into the glass, so that's definitely not it.

When it comes to carbonation, I am not sure. I have heard that the beer should be fully carbed but I have also heard that it helps to be slightly undercarbed.

You need to be a bit more precise in your terminology. "Fully carbed" or "undercarbed" can have vastly different meanings depending on what the desired end carbonation level is. Generally you want to carb beer to be served on nitro to around 1.2-1.8 vol, which is considered to be very low carbonation for most styles. Below 1.0 vol you really don't have enough carbonation to create the desired effect, and much above 2.0 you're likely to have a foamy and uncontrollable mess. IMO 1.6-1.8 vol is the sweet spot, but YMMV.

My best guess with the very limited info provided is that you're using a gas blend that's too low in CO2 for your serving temp and pressure, resulting in lower than ideal carbonation levels. G-Mix is the most common blend and it's only 25% CO2 and 75% nitrogen. Guinness is carbed to the low end of the spectrum at 1.2-1.3 vol, and the G-Mix is designed for pouring Guinness (hence the G in the name) in a commercial setting, which is to say very very cold. Using G-Mix for warmer temps or higher desired carb levels will typically either result in undercarbed beer, or a serving pressure so high that the nitro faucet wants to create a foamy mess rather than a nice cascading head.

There are some really useful online calculators for nitro set-ups, but you have to understand the mechanics of serving on nitro to be able to fully utilize them.
http://mcdantim.mobi/

My next guess would be an issue with the recipe. Too low of an FG can prevent the head from sticking around when pouring nitro, as can oils (like those found in coffee). If you used a darker roast coffee this time than last time, it could result in a lot more head retention killing oils.

 

[masonsjax]

It's probably slightly undercarbed. Try bumping the pressure up a hair, maybe by 3 psi and give it a week. It's easy to overcarb on nitro, but this sounds like you could use a touch more.

 

[JuanMoore]

It's probably slightly undercarbed. Try bumping the pressure up a hair, maybe by 3 psi and give it a week. It's easy to overcarb on nitro, but this sounds like you could use a touch more.

Not very easy to over carb when using g-mix though. At 40F you'd have to be at nearly 70psi to get up to 2.0 vol. The faucet will generally pour a foamy mess over 45psi regardless of the carb level though.

And with how long pressure changes take to change carb levels with mixed gas, it's a lot easier to just use a calculator like I posted above to determine the correct pressure than trial and error. It'll also determine if the required pressure is even reasonable, or if another variable like serving temp or gas blend needs to be adjusted.

 

[hopjunkie26]

So my kegerator is right around 35 degrees give or take a degree. (didn't realize it was running that cold so I have turned it down a bit)

PSI is set at 15 on an 80/20 beer gas mixture.

As far as the recipe goes, it had an FG of 1.012 (SG was 1.068) and I use the same coffee (cold steeped, added 24 hours before begging) each time I make it.

Below are a couple pictures of the pour (this is a beer clean glass that I hand wash after every use)

 

[hopjunkie26]

And thank you to HBT for uploading them sideways...I think you guys get it though

 

[hopjunkie26]

Looking at the recipe, it is no more than 2-row, chocolate malt and some 60L. Perhaps I should throw 1/2 to 3/4 of a lb of carpapils in there to help with the head?

 

[JuanMoore]

So my kegerator is right around 35 degrees give or take a degree. (didn't realize it was running that cold so I have turned it down a bit)

PSI is set at 15 on an 80/20 beer gas mixture.

Is that 80% nitrogen and 20% CO2?

 

[falkaveli]

15psi quite a bit low for beer gas mixture. Figure you're only pushing 3psi of CO2 to maintain carb. I generally push 30psi or so.

 

[hopjunkie26]

Yes, 80% Nitrogen / 20% CO2.

Maybe I crank it up a bit and see if that helps...the good thing is that the beer tastes fine. Just not the thick, creamy mouthfeel I was hoping for.

 

[JuanMoore]

Yes, 80% Nitrogen / 20% CO2.

Maybe I crank it up a bit and see if that helps...the good thing is that the beer tastes fine. Just not the thick, creamy mouthfeel I was hoping for.

A bit? How about a whole lot. First, nitro faucets usually work best in the neighborhood of 30psi. Second, if you use the calculator I linked earlier, you'll find that you'll only be able to maintain 0.6vol at your pressure/temp/gas blend. To get to a very modest 1.2 vol you'd need ~47 psi. And that's assuming 35F, you'll need even higher pressure now that you've increased the temp.

The fact that you're getting any cascading effect at that pressure tells me you still have a fair amount of carbonation left from what you did with CO2, so I'd try something in the 25-30 psi range before trying to get all the way to the equilibrium pressure.

The issue long term will be your gas blend. At that low CO2 concentration you'll never be able to keep equilibrium pressure without having foaming issues, because that pressure will be too high. You'll need to keep it closer to 30 psi, and either carb to desired level with CO2 and let it slowly lose carbonation through the life of the keg, or live with a really low carb level.

 

[bcrawfo2]

Agree. ~30 psi. You really need to push that beer thru the restrictor.
And...in my experience...you don't need to worry about a long line between keg and faucet. I have about three feet

 

[hopjunkie26]

Cranked it up to 30psi this morning and this evening it is a much thicker and creamier head that doesn't dissipate...looks like that did the trick.

Thanks to everyone for the advice.

Cheers!

 

[pronoyyd]

This might Help
www.columnm.com

 

[masonsjax]

Since when are most beers 30% nitrogen? Most beers use 100% carbon dioxide. Nitro beers are also not "infused" with nitrogen, since it's not easily dissolved in liquid. Instead, nitrogen is just a way to pressurize without carbonation.