I agree with you completely about making the cold brew separately so that you have some on hand! Other reason is that I very much prefer the drip method of making cold brew as opposed to the infusion method. Just seems that much smoother to me.

While I have not had the cascading effect to the full level of a commercial coffee house using a true stout type tap and N2 vs N2O ... I do get somewhat of a cascading effect and I actually do like the slight natural sweetness of the N2O! Just keeping in mind this is a home version of a commercial thing ... I have been very pleased so far.

I did find another source of the 16g N2O cartridges at bestwhip.com ... They are about a third of the price of buying them from Growlerworks ($5 per box of 5 vs $15). I used one of the BestWhip cartridges yesterday and it worked just as well as the ones that came with the uKeg Nitro.

I just got one yesterday and haven't tried it yet. So I will follow this thread.

Here some answers GrowlerWorks put on their Kickstarter Q&A regarding the choice of N2O:

N2 is what is most commonly used with the mass produced Nitro coffees as it is easier to get in larger quantities and will work if you are able to find the right size cartridges. N2O is inert (most commonly used for keeping dairy in whipped cream fresh) and will not oxidize the coffee which is why we went this direction. We have put the uKeg through a variety of scenarios and even had the Starbuck's coffee counsel do some testing over a two week period and found that there was no significant different in what they are pouring and what is poured from the uKeg Nitro. To your point the Oxygen in N2O can be an oxidizer but the temperature would have to soar up high and only then would there be issues in freshness. Regarding the volume of gas in the cartridges, you will have plenty to infuse the coffee, keep it fresh, pour it all out, and a bit to help rinse out the tubing before filling it again. I am looking for documentation regarding the third part of your question on mouthfeel and fizz, but until then I do hope that helps and if you have any other questions, please let us know.

Nitrous oxide is completely inert at room temperature, which is why its used as to store things like cream and milk for several months. We also use nitrous because it's much more dense when stored, it also infuses faster and at lower pressures than nitrogen. As for taste, the nitrous does add a little creaminess to the coffee, mostly from the aeration of the coffee, similar to nitrogen. It also desaturates slower than nitrogen, which means the creaminess lasts longer instead of dissipating in a minute or two. You don't get a "fizzy" sensation because the nitrous doesn't acidify the coffee as CO2 would.

The uKeg Nitro uses one N2O cartridge per fill. This is enough to infuse the coffee with the gas as well as have enough left to dispense the full contents of the uKeg. There will also be just enough in there to rinse out your uKeg for storage.

This thread also discusses the topic.

Anyone try nitro cold brew?

I"ve not had any success with my Ukeg Nitro. GrowlerWorks has inspected my unit and did replaces some seals which helped with dripping from spout after use, but I'm not get any microbubbles.

I brew outside of the keg (10 oz coffee to 80 oz of water), chill keg with ice water, pour in coffee, set to infuse, let sit overnight in fridge. The next morning the pressure gauge is still in the infuse zone, but what comes out is slight carbonated (a little head), but no cascading. It also seems to impart a slight bitter finishing note to the coffee as compared to drinking it pre-keg.

By the second day of sitting in the fridge, the bubbles are further reduced, though still showing proper pressure.

Any advice? Brewing ratios that are successful?

Thanks

Has anyone found N2 cartridges that are compatible with the uKeg Nitro? Looking to try them to compare. I have found that the N2O stays dissolved almost too well. When I first poured, I poured it like you would a beer down the side of the glass and got almost no foam or cascading. I thought it was odd because when I tasted it it tasted a little sweeter and had the mouthfeel of nitro. I then realized that I would need more nucleation sites to get it when poured. I have both poured aggressively into the bottom of the glass and served over ice with better results. N2 would definitely produce better cascading, however, as its solubility is much less in water.

I didn't see any in my searching. I also noted that it takes two bags per batch and while the bags aren't expensive, GrowlerWorks wants to charge more than the price of bags to ship them.

Are people using the bags? or adding their own cold brew?

I've been doing the brew outside and then adding to the chilled growler for charging. My UKeg nitro came with 2 drip mats and no brew bags so I had no choice.

I plan on trying the hatfields n2. Spec is similar in size to the standard sized N20 whip cream chargers I've been using, with an adapter, while I wait for my UKeg N20 charger to come in the mail.

What kind of adapter please?

So the green end plug for lack of a better term? Did you make it or buy it? So just to be clear you are using N2 while you wait for the N2o to come in the mail? Thanks Kran.

The green plug is just a 3D printed piece to make up the difference in size of the charger.

I'm currently using isi nitro cartridges while I wait for the Ukeg ones to arrive, I believe both of these are N20. I will also try the Hatfield N2 once I exhaust the Ukeg chargers.