Nitros 70/30

[Elliott 22]

Hey everyone
Looking at having a designated stout tap and getting some 70/30 gas and mixed regulator.

but was wondering can I do a short draw system with the tap mounted direct on the keg with an nukatap flow control and stout spout facet?

or will this not work?
Also do I carbonate normally with co2 to volume I want then set mixed gas 70/30 to serving pressure?

 

[AnimatedGIF]

Hi @Elliott 22 - Did you try this? I imagine it would result in a lot of foam!
Probably a little late to be of any use to you, but I think you carb and serve with the 70/30, likely at around 40psi or more.

 

[RoomWithABrew]

I think first question yes.

Second no. You will have way to many vols CO2 for beer gas. Unless you carbonate to about 1.2 vols CO2.

 

[LeeH]

I’ve always got better results with ‘carbing’ with the mixed over 2 weeks. Seems to get that perfect creamy pint. Maybe some of the N gets into the beer.

 

[peebee]

Crikey, bet @Elliott 22 is surprised to see his ancient unanswered post suddenly attracting all this attention!

Let me have a look too ...

@AnimatedGIF said "40psi"? Yeap ... or as I'd put it, "bone crunching". @RoomWithABrew said "1.2 vols of CO2" ... hmm, that takes a bit more figuring out:

"70/30 gas". You actually mean "30/70" - it's an unwritten "law" to state the CO2 first, but gawd knows who decided that? Probably one "above-themselves" gas trader? i.e. 30% CO2. And we're to be working with "absolute pressure" so that's 40psi ("psig" to be proper correct) plus the pressure of the atmosphere (standard is 14.7psi) ... or 54.7psi. Then the bit I like ... the "physics"! "Partial Pressure", the reason I like it is it's so easy and even an id'jet like me can do it ... 30% of 54.7 is 16.41psi of CO2. Convert that back to relative pressure ... 16.4-14.7 = 1.7psig. Which will create, as dissolved CO2 ... hang-on, I'll get Beersmith to figure that out 'cos it's only way I know how ... let's say a cool cellar temperature of 11°C ... 1.2 "volumes" of CO2 ...

Cocky so-so that @RoomWithABrew i'n'he!

But don't tell the kegheads. They can cope with 40psi, but turn a bit pale at 1.7psi.

Anyway, as @LeeH says, a bit of time and you can get some Nitrogen in to it too. Tonsil freezing frigid temperatures help too. Perhaps even one of those special tap thingies? But you don't need them. Patience and pure CO2 will do. "Stout" didn't come into existence when Guinness start phatting about with Nitrogen!

 

[RoomWithABrew]

@peebee

You explained the pressures better than I can, thank you.
I'd love to find out more about the pre nitro Guinness method. I think it was a cask system one of young running stout and an older " off" or perhaps keeping stout. Blended by the publican in the glass via a beer engine.
But facts are eluding me.
A beer engine with a stout creamer sparkler I think gives a very similar pour to nitro stout.
To me a nitro stout has a different taste to the same under CO2 whether via a sparkler.
Weather okay yesterday at the football quarter final to cheer you up pre match.

 

[peebee]

plus the pressure of the atmosphere (standard is 14.7psi) ...

Here ... I've done sum'it wrong! I've added the standard pressure twice? Better sort that out ... (one and one is two, two and ... help!)

Meanwhile!

I'd love to find out more about the pre nitro Guinness method. I think it was a cask system one of young running stout and an older " off" or perhaps keeping stout. Blended by the publican in the glass via a beer engine.
But facts are eluding me.

I tried it a while ago. Only once. Miserable failure, I'll try dig out the details and then you can have a miserable failure too?

Anyway. You can't make me jealous with piccies of blue sky at moment ... it's suddenly got very hot and sunny here; way too hot to wear coats and caps like those in your piccie! We're playing cricket over here, not football ... so, nah, nah!

 

[peebee]

It was the old matured Guinness in the trade casks. Not carbonated ("low" cask). And the small "high" cask with very thick staves to hold the pressure, filled with newly fermented Guinness and a huge slug of unfermented wort. That put the head on the poured beer.

I might dig up a description from someone more reliable than me later!

 

[RoomWithABrew]

It was the old matured Guinness in the trade casks. Not carbonated ("low" cask). And the small "high" cask with very thick staves to hold the pressure, filled with newly fermented Guinness and a huge slug of unfermented wort. That put the head on the poured beer.

I might dig up a description from someone more reliable than me later!

Thank you that would be great.
It's not in the Guinness book.
Yes I wore my coat, got sunburnt and there were still nutcases ( locals ) in shorts and T shirts.
I think you start football tomorrow?

 

[Hazelwood Brewery]

a bit of time and you can get some Nitrogen in to it too.

About a month to get nitro into your beer at 40psi. Before then it’s really just the CO2 from the mixed gas that carbonates the beer.

Perhaps even one of those special tap thingies? But you don't need them.

A stout spout is a good idea when using nitro for two reasons; serving at 40psi is likely to be troublesome unless you tangle yourself in several feet of 3/16 beer line - the restrictor plate reduces pressure at the tap; the restrictor plate has small holes to let the beer through but also to create turbulence and encourage the nitro to do it’s magic.

To me a nitro stout has a different taste to the same under CO2 whether via a sparkler.

Nitro changes both the flavour and texture of the beer; it’s smooths any bitter roasty notes and it gives the beer a softer mouthfeel, some people describe it as more velvety. Nitro is supposed to mute hoppiness though so shouldn’t be used on hoppy beers. I think the science behind this is that the nitro bubbles hold the aroma where the more excitable CO2 bubbles throw the aroma into the air as they burst. I’ve never tried nitro with hoppy beers though so I can’t speak from experience here.

 

[peebee]

Thank you that would be great.
It's not in the Guinness book.

No, you won't get it from Guinness! They spent a lot of money in the 1950s developing their "keg" "Guinness" with nitrogen conditioning, so they are not going to suggest there's a better (but with more overheads) way. I'm sure they are joyous hearing people say you need nitrogen to serve stout.

Here's a link to an article by Gary Gillman covering their "high-low" system. They were introducing nitrogen conditioning in Ireland in the 1950s, but it was later in the rest of the world. The UK was still getting "high" and "low" casks in the 1960s (into the 1970s?), and I remember being told about them coming across on the ferry.

https://www.beeretseq.com/some-thoughts-on-guinness/

... I think you start football tomorrow?

Groan. I don't want to be reminded. Though I know you delight in reminding us "Winter is on the way".

Here ... I've done sum'it wrong! I've added the standard pressure twice? Better sort that out

I was having a "Flat Stanley" moment (lacking in a dimension or so). I was ****-a-hoop about knowing a bit of Physics that was easy to understand, so I was overlooking that its Physics ... and it most certainly isn't easy to understand! Gawd knows how long I've harboured these "Partial Pressure" fictions. But I guess I wasn't being clueless; I just need a few more clues!

 

[Elliott 22]

@peebee absolutely loving the fact the threads been resurrected, some great info from everyone and I have learned a lot about kegging since I asked but still to venture into 30/70 not 70/30 as stated gas and am waiting to build a bigger kegerator, currently away with the family in kernow and hoping to convince my wife that the 1hr 30 min trip from mousehole to verdant brewery is an essential trip

 

[peebee]

I was having a "Flat Stanley" moment (lacking in a dimension or so). ...

Seems my explanation was all-to-pot, but the sums come out right all-the-same? 40psig of 30/70 gas comes out at as the equivalent of 1.71psig pure CO2 (creating 1.2 "volumes" of dissolved CO2 @ 11°C). I think?! Sort of explains why no-one has pulled me up for getting it wrong.

Anyway. Too much unnecessary maths for this early in the morning (as if there's a right time).

Ooo, another reply ... and I'm still not being bludgeoned for getting me numbers twisted ... Morning @Elliott 22!

 

[Hazelwood Brewery]

This may help take out the guesswork, and the maths!

 

[peebee]

This may help take out the guesswork, and the maths!

Thanks very much! At last, here's something to compare my babbling with!

Right, so I've got 40psi, 1.2 "volumes" of CO2, and I reckoned 11°C ...

Err ... that is just a little bit creepy! I'm off for a lie down.

 

[RoomWithABrew]

Thanks great chart, been looking for something like that.

Although my cylinder we weren't completely sure of the ratio but mine seems good with 35psi.

Changing to a new system soon so may well have questions.

 

[AnimatedGIF]

I have mine at 3°C, 40psi and it's just right for what I want.

 

[chopps]

Thanks great chart, been looking for something like that.

Although my cylinder we weren't completely sure of the ratio but mine seems good with 35psi.

Changing to a new system soon so may well have questions.

Some good charts at Jolly Good Beer's website These remind me of his, perhaps that's the origin?

 

[Hazelwood Brewery]

Some good charts at Jolly Good Beer's website These remind me of his, perhaps that's the origin?

It is.

 

[Sorcerers Apprentice]