CO2 Shortage & Capture

[mashpaddled]

Are there any "flat beer" styles that are served in Europe? I have drank lots of different styles and lots of different beers in Europe and have never come across a flat style(including cask). I mentioned cask ale since I believe that is the only beer that the guy could possibly be mentioning since it is not pressured with bottled co2. By the way, I am just critiquing what the guy in the interview said. Watch the video in the first post from 1:32-1:42 to see what I mean.

There is flat lambic sold but it's definitely a rare breed. "Flat" in the sense cask ale has lower carbonation isn't as obscure. There are other parts of Europe where you can find beers naturally carbonated in kegs and served by gravity and even occasionally with a beer engine. If you've never had lagers served out of a gravity keg, you're missing out.

 

[mashpaddled]

I'm curious as to the ongoing costs to make this type of scheme viable.

With economies of scale in the industrial market, a 10lb tank of CO2 for exchange here in central Iowa is around $29. This is at the beverage CO2 supplier, could be different if utilizing a welding gas supplier like Praxxair, etc.

I fully realize I'm leaning on the industry at large, as well as the fossil fuel segment to generate all this gas for my tanks, which makes it difficult to take those "savings" into account vs making your own CO2.

Watching a friend make mead for the last 2 years with the absolute cheapest champagne yeast (got a 10pk of 11.5g sachets for $4.00) it never occurred to me to use this method for generating CO2 for my own brews until now.

Now the quandry I have is whether to attempt to make a drinkable brew while trying to harvest all this CO2 gas, or just dedicate a tank to a sugar wash + DAP/nutrients?

First world problems I know, right?

One problem is you can fill keg after keg with low pressure CO2 storage during fermentation but then you won't have a lot of pressure to make that CO2 leave the keg or move beer out of a different keg. You can't just pressurize the storage or reactor kegs during most of fermentation because excessive CO2 and pressure will impair continued fermentation. You can get away with this towards the end of fermentation and maybe get a keg or two of pressurized CO2.

The other major problem is once your CO2 kegs expel enough CO2 to have the same pressure as your beer-filled kegs you won't be able to push any more beer out because there's no pressure difference moving CO2 from one keg to another. You're going to need several kegs of CO2 just to drink through one keg of beer. That's a lot of work and a lot of occupied kegs. How much of your time is worth $29?

 

[McMullan]

@renstyle
Very odd the link is in the email I received but not in your post.
My recent 5kg refill cost 65 us dollars equivalent so a tad more expensive down here to refill in New Zealand.

Still a lot cheaper than in Norway, for a number of years now. There's no competition whatsoever. I now opt for 450g sodastream canisters, purely based on an assumption it's better quality (beverage) CO2. Price difference is practically zero. And it's so expensive to get a gas cylinder checked and recertified as fit-for-use they're basically 'disposable' items even though expensive to buy, which you have to do, due to no deposit schemes. It's a total ripoff and environmentally shameful to dump perfectly good cylinders.

 

[renstyle]

@renstyle
That thread you mention has a very comprehensive treatise by @doug293cz on purging.
You forgot to insert the link though.
This is it
https://www.homebrewtalk.com/threads/keg-purging-with-active-fermentation.628658/#post-8004741

Thanks @DuncB! It's Saturday and I didn't have the energy to look up that specific link. It's golden tho.

 

[renstyle]

@renstyle
Very odd the link is in the email I received but not in your post.
My recent 5kg refill cost 65 us dollars equivalent so a tad more expensive down here to refill in New Zealand.

It sounds like this method may prove more economical in your neck of the woods, while (for now at least) it's just an intellectual/satisfy-my-curiosity type of factor where I'm at.

 

[renstyle]

Okay, so given that I have 2 spare corny kegs beyond the 4 needed to fill my keezer....

I could potentially use one (or both) keg(s) to house CO2 generated from a sugar-wash/2-row wort + DAP/nutrients mix.

Since a normal fermentation can get to 30+ PSI for many recipes that offer spunding at that pressure, I'm curious as to how high we can get before the yeast conks out if we are attempting to maximize CO2 production at the expense of the quality of the end product?

Trying to guage the ROI of going this route vs just working with the CO2 offered by a regular fermentation as a mechanism for dispensing my brews vs a CO2 tank.

 

[renstyle]

One problem is you can fill keg after keg with low pressure CO2 storage during fermentation but then you won't have a lot of pressure to make that CO2 leave the keg or move beer out of a different keg. You can't just pressurize the storage or reactor kegs during most of fermentation because excessive CO2 and pressure will impair continued fermentation. You can get away with this towards the end of fermentation and maybe get a keg or two of pressurized CO2.

The other major problem is once your CO2 kegs expel enough CO2 to have the same pressure as your beer-filled kegs you won't be able to push any more beer out because there's no pressure difference moving CO2 from one keg to another. You're going to need several kegs of CO2 just to drink through one keg of beer. That's a lot of work and a lot of occupied kegs. How much of your time is worth $29?

That's why I was wondering the "over/under" whether capturing CO2 during a normal fermentation, ideally under pressure of a wanted recipe would obviate the need for an independent sugar-wash-to-CO2 fermentation with no end product beyond the CO2 produced would be more "economical" to a home brewer.

 

[DuncB]

Maybe a small compressor between the ferment gas engine and the storage corny keg which have a very high pressure rating with a non return valve inbetween.

 

[seatazzz]

So here's a thought. I've recently started doing pressure transfers from my fermonster to the keg; works great. What would happen if, next time I brew, I have something ready to keg; run a line from the fermonster pressure lid to that filled keg? I know it wouldn't be completely carbonated just from the co2 generated from the fermentation, but it would get a start that I could finish with my tank. Anyone tried this? And if so, results? If nothing else I wouldn't be wasting all that co2 from the fermentation.

 

[DuncB]

All of my keg beers are fully carbonated with ferment gas and fined if needed before closed pressure transfer to the serving keg.
I'm using a fermenter that can take up to 35psi, you need high pressures to get the correct vols at the ferment temp. Then when you cold crash pressure falls but carbonation stays in balance.
I'm unfamiliar with a fermonsters and their pressure capabilities.
You will need a spunding valve, but it's an old technique that has " become new"

 

[garibaldi83]

I keg with a couple points left and the keg is self serving for while (the taps are the same height as the tops of the kegs which helps). Brews that are lagering in the same keezer are kegged with a few points left and with a gas to gas jumper I eventually use those to push other beers to the taps until they reach the right co2 volume. I rarely need bottle gas and 100% pure co2 is what most of my brews ever see from cradle to the grave. I'm sure we all have some cellaring and serving tricks that might come in handy going forward.

This is fascinating, now to me as a layman brewer it would seem that natural carbonation would do the same thing and push out beer from the keg, especially at the 15 psi range, as forced carb at 15 psi from a tank. What am I missing? Everything I have been told and read states you still need bottle gas.

 

[bracconiere]

This is fascinating, now to me as a layman brewer it would seem that natural carbonation would do the same thing and push out beer from the keg, especially at the 15 psi range, as forced carb at 15 psi from a tank. What am I missing? Everything I have been told and read states you still need bottle gas.

as you push the PSI goes down without replacing it?

edit: and co2 and water don't like either, and need to be forced into each other..their are people that naturally carb kegs, but that would only get a couple pours before you'll lose the carb, and pressure to push it... there are people that use HIGH PSI with nitrogen/co2 'beer gas' also so that they can serve their beer flat?

 

[AlexKay]

I don’t think I saw a mention of purifying CO2, but this is a necessity and an additional cost. Fermentation can smell, sometimes quite a lot; you don’t want to introduce those volatiles (H2S, DMS, and what have you) into finished beer. Not such a problem with spunding because you’re doing that at the end of fermentation when most of the nasty stuff has worked it’s way out, but if you’re capturing CO2 early in, it’s an issue.

 

[mscroggi]

This is interesting reading on the issue - The CO2 Shortage | Why is there a CO2 shortage for beer makers?