Oops, once again, I did not refresh before posting, so this probably cross-posts with many of the updates...
I don’t know any bars that serve Guinness stout from kegs carbonated with co2. All I know use the nitrogen (with a little co2) mixture. And the kegerator faucet is different in nitro beers. Here’s DW getting certified as pouring the perfect pint at the brewery in Dublin. The nitro faucet shows up in the pic.
Finally found Nitro Pepsi Draft Cola, it’s wonderful - and I can’t stand Pepsi (only Coca-Cola will do, so I hope they do Coke Nitro). Evidently there’s a Nitro Vanilla Pepsi too.
Cold brew coffee is better with nitro. And beer, at least dark beers like Guinness and Firestone Walker Nitro Merlin Milk Stout, are much better.
Nitro makes everything smoother and creamier than CO2.
Oh wait, so you are saying they are charging soda with nitrogen now? Cool.
For clarity - the Nitrogen does not
replace the CO2. It is used in conjunction with CO2 as part of the "delivery system".
Beer/water does not absorb Nitrogen. You won't get a 'fizzy' drink if you apply nitrogen under pressure. The fizz comes from the fact that beer/water
will absorb CO2. When this is done under pressure (~ 12PSI of CO2 for most beers), the beer absorbs it, and after some time it will come to a state of equalization (which takes from mere seconds to weeks, depending on how 'aggressively' it is done).
When that beer is poured from the tap or the can/bottle is opened, it drops from the 12PSI in the container, to atmospheric pressure. So the CO2 is released, comes out of solution, and provides the 'fizz'. And just like the beer didn't absorb the CO2 immediately, it doesn't release it immediately either. So your beer keeps bubbling for a while in the glass.
IIRC, Guinness started using Nitrogen in the delivery system as their taps were far from the kegs in the original tap room. If you pump up the CO2 enough to overcome all that resistance to flow in the lines, you end up with a beer that is too fizzy (all foam). So they carbonate it normally with CO2, then use Nitrogen at a higher pressure to push it to the tap.
The side benefit of the nitrogen is that it pushes some of the CO2 out of solution as it is poured, creating that creamy mouthfeel that many of us appreciate in some beers. I haven't tried this, but I imagine a Nitro beer would go flat in the glass a little quicker than a pure CO2 beer, as the Nitro has pushed some of that CO2 out.
Here's one way home-brewers do it:
https://www.thebeveragepeople.com/products/kegging/tank-filled-with-beer-gas.html
Beer gas is 75% Nitro, 25% CO2.
and more info (hopefully backs up my post, as I was going from memory!)
https://byo.com/article/nitrogen-draft-tap-projects/
Another way to do this on the cheap (and amaze your friends and family!) is to use a syringe, suck some regular CO2 beer from your glass into it along with some air (which is 78% nitrogen - for free!). Then shoot this into the beer, with the syringe submerged.
It will take some practice, but you can get that nice creamy head, and the cascade that you see in a Guinness. Should work for soda too.
also - if you have ever seen wine poured from a tap, or soda fountain, they use 100% Nitro to push that, so they don't end up carbonating the wine (and yes, I've force carbed some wine at home to make a sparkling wine, just for fun).
more also: And cans of non-carbonated beverages (fruit juice) are filled with Nitro under pressure. This provides some strength to the can to resists denting, while not carbonating the drink. Without that pressure, the can would crush easily.
-ERD50