Coffee on tap

[HarpoonColdBrewNZ]

So our experience with pouring is that the cascade and also the delicious fine-textured head are attainable using pure nitrogen and a stout tap. After reading about enough people being unimpressed with the carbonic acid formation that made their coffee too bitter, we decided not to bother trying beer gas blends and instead just ramped up the nitro pressure on our keg for 24 hours at a low temp. Lots of people will try and tell you that nitrogen is insoluble, that's not true - but rather it's way less soluble than CO2, so you need higher pressure and lower temperature to encourage it into solution in the coffee.
We pressurise our 20L kegs at 3 bar and 1 degree C for 24 hours, and then pour at the same pressure through a stout tap and get the cascade effect along with about 10mm of creamy head on top that lasts for ages in the glass. All on pure nitrogen.

 

[Tiber_Brew]

So our experience with pouring is that the cascade and also the delicious fine-textured head are attainable using pure nitrogen and a stout tap. After reading about enough people being unimpressed with the carbonic acid formation that made their coffee too bitter, we decided not to bother trying beer gas blends and instead just ramped up the nitro pressure on our keg for 24 hours at a low temp. Lots of people will try and tell you that nitrogen is insoluble, that's not true - but rather it's way less soluble than CO2, so you need higher pressure and lower temperature to encourage it into solution in the coffee.
We pressurise our 20L kegs at 3 bar and 1 degree C for 24 hours, and then pour at the same pressure through a stout tap and get the cascade effect along with about 10mm of creamy head on top that lasts for ages in the glass. All on pure nitrogen.

I don't think anyone is making the claim that N2 won't dissolve in water based solutions; it's that it dissolves in negligible amounts in draught settings. Nitrogen was chosen for the stout draught design because of it's ability to push water based solutions at high pressure without a significant change in total dissolved gas.

I won't argue with your results. Just keep in mind that there were probably several types of dissolved gasses in your coffee when it went into the keg. Any of which could easily nucleate under the pressure and shear forces incurred by the stout tap, yielding a cascading effect.

Hey, if you found something that works for you, keep doing it.

 

[jcav]

Hi everyone, I saw this today what do you all think?

http://www.nitrocoldpress.com/?icn=NBHomepage&NitroColdPress

I have a small 2.5 gallon keg for cider could be good for nitro coffee!

John

 

[BlackInk]

I used to use this brew method and do two gallons at a time: http://thepioneerwoman.com/cooking/perfect-iced-coffee/

Then pour in a corny at 10 psi on nitro...and I got basically what you're talking about here. It's just cold coffee that lasts a little longer. Kind of fun but whoopity do.

But now...

-Prep (new seals) and sanitize 2.5 corny.
-Pour in 2lbs of a dark roast coffee of choice...I like something with chocolate notes.
-Add 2 gallons of distilled water
-pressurize with nitro at 20psi (over bleed off the air to get all o2 out)
-Shake like a mother, add more nitro, shake, and more shake till you get to 50psi
-Drop in your keezer for a while

After 4-6 days: prep/sanitize new 2.5 corny, keg to keg line with filter in the middle. I prime my filter (and as much to my lines that I can) with room temp coffee from the Keurig. We're trying to keep o2 out! Pressurize new keg, over bleed air out make all connections.

-Bleed pressure out of brew keg
-Attach nitro and set regulator to 3-5psi on brew keg
-transfer to serving keg slowly releasing nitro in the serving keg to fill with filtered coffee
-Once the coffee is transferred to the serving keg attach the nitro, crank it up to 30psi and just shake the crap out of it. You'll hear additional gas go in like force carbing, but you're not really carbing.

Grab a chilled (from the fridge not freezer) tulip glass, put a spoonful of sweet condensed milk in the bottom add a dash of vanilla to bring out the chocolate flavors and open the stout tap dead center. Or take it black...which might be the strongest coffee you've ever had. Whatever floats your boat. It pours like Guinness and stays fresh for a loooong time.

 

[jcav]

Excellent BlackInk! I might have to try this!

John

 

[user 190343]

I recently did a cold-brew coffee on nitro setup. I found it very difficult to find solid info on it and have been figuring it out over the last few weeks.

I used my brew kettle to make the actual cold brew coffee. I put 2lbs of good French roast coffee(Willougyby's Columbia Supremo) that was course ground for French press. I put the coffee into a 5gal paint strainer bag from Home Depot and tied up the top with plain dental floss, both of which I dipped in my StarSan bucket first. I added 3gal of Poland Spring water to the kettle, then dunked the bag a few times. I used a sanitized metal spatula to push it fully under the water and hold it there for a minute to get air out. I then purged the kettle with CO2 to try to remove oxygen and strapped the lid on tight with a bungie cord. I put in the garage overnight where is was probably about 55° and left it for 24 hours or so. I brought it into the kitchen, pulled the paint strainer coffee bag and dumped it(it smelled so good.) I then drained from my kettle via siphon to a santized and CO2 purged keg(I didn't have my Nitrogen tank filled yet.) It left a lot of coffee sludge in the bottom of the kettle that had settled out. I put in in my kegerator to cool for 24 hours, but not hooked up to anything.

I put the coffee keg on pure nitro, not beer-gass. Purged the CO2 off with nitro, then jacked up the pressure to 20lbs and left on for 24 hours and hooked up my stout tap. Cold coffee with no Guinness like head, which left me disappointed. Purged again and upped the pressure to 25lbs. Next day, same "flat" coffee. It's really good, but flat. Jacked up the pressure to 30lbs. Next day, same "flat" coffee, took apart restrictor and flow control on stout faucet to make sure those weren't the problem. They weren't. I jacked up the pressure to 40lbs... after 3 or 4 more days of samples, still pretty flat until 7-8 days and low and behold, now it's almost over-"nitro'd", but it's got that creamy head I was looking for. I enjoyed a delicious cold coffee this morning on my way to work. My next step is going to bleed the pressure on the keg and bring the pressure back to 30-35lbs. I'll try to post a pic of the results.

So I'm finally starting to get to where I want, but it's taken over a week. From the little I could find on the Internet, I thought the nitro charging would only take 24 hours or so, but that clearly wasn't the case. I think a lot of people are just pushing it with nitro and not infusing it like Guinness. So if you are trying, keep my experience in mind and don't get disappointed after a day or 2. I'll also probably use some of @BlackInk's procedure like shaking the keg. I'll have to look into the filtering like he did too.