Fermenting Under Pressure

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What do they do with the Carbon dioxide do they just vent or reclaim A groundbreaking plant where carbon dioxide is sucked from the air before being resold has opened in Switzerland that sounds like a global warming **** they sell to green houses if you collect could do the same from beer brewing.
 
So there's great results seemingly over a vast range of pressures, the common denominator being minimizing or eliminating oxidization. Is it reasonable to assume this is actually key to the whole process and the pressure thing being a useful side effect?
 
As I have said before after reading this whole thread what piqued my curiosity, was if it is so good why aren't any of the craft and bigger breweries doing it, I think Dan nailed it in his post 425 its all about the esters.
The pressure ferment subdue the esters so I would presume that the major players aren't prepared to give up the yeast enhanced flavours.
And repeating what I said in my last post, if you like what you are doing stick with it, I will continue not to apply any pressure until the final couple of points, in saying that I mostly drink ales and I keep them at 10 to 15 degrees C even the hop driven AIPA's, but I will try a pressure ferment on the next hop forward one I brew.
I was happy with my first attempt, apart from losing a couple of points, pitched yeast on the Sunday and drinking it on the following Saturday it was still green but not bad to drink.
Cold space I would be checking your gauge and your PRV, I pressure tested my manifold yesterday the gauge was spot on but the calibrations on the PRV was way off, 25 psi to be exact (25 psi was actually zero) not that I am worried about it I will just synchronize the two readings.
wynnum the big breweries do capture their CO2 and use it for purging and carbonating and any excess is sold. A NASA home brewer made a system for reclaiming CO2, they can freeze liquify or make oxygen with it.
https://spinoff.nasa.gov/Spinoff2016/cg_3.html
 
Yep, if it's working for one, then don't change anything.

I love my little craft house now, all humming along lovely and the beers are better than what I can buy so I will stick with everything.

Cheers
 
I love my little craft house now, all humming along lovely and the beers are better than what I can buy so I will stick with everything.

Cheers

Could not agree more. PF has sparked a renewed love of this sport.
Unfortunately it also sparked way too much spending.
Apparently this is a little too much. 15138335256301790950904.jpg
 
Getting a bit off topic, but pressure fermenting in the 23L kegs also sparked an idea to brew to suit them.
I have brewed higher sg and higher mash temp then dilute post ferment. The results have been great.
That way i can take a 29L cube and split it between the two kegs. Then when i transfer, the receiving keg already has the water, biofine and hop ball if required.
To get the dilution ratio, i just water down the hydro sample to the required gravity then calculate that to 19L.

Cheers
 
Getting a bit off topic, but pressure fermenting in the 23L kegs also sparked an idea to brew to suit them.
I have brewed higher sg and higher mash temp then dilute post ferment. The results have been great.
That way i can take a 29L cube and split it between the two kegs. Then when i transfer, the receiving keg already has the water, biofine and hop ball if required.
To get the dilution ratio, i just water down the hydro sample to the required gravity then calculate that to 19L.

Cheers
What about the head space in the keg? And the water?
 
Getting a bit off topic, but pressure fermenting in the 23L kegs also sparked an idea to brew to suit them.
I have brewed higher sg and higher mash temp then dilute post ferment. The results have been great.
That way i can take a 29L cube and split it between the two kegs. Then when i transfer, the receiving keg already has the water, biofine and hop ball if required.
To get the dilution ratio, i just water down the hydro sample to the required gravity then calculate that to 19L.

Cheers
I used to do something similar in my bucket of death days,

I brew up an extract receipe in the fermenter with some steeped grains and por hops in a bag with an immersion heater over the side, I did a powers bitter type receipe, it was scetchy as lol as the fermenter would get soft etc lol,
I'd brew a double batch strength, light malt extract , crystal grain steeped on stove, pinch salt and por hops then seal up and leave to cool down over night, pitch yeast, ferment out high grav, then split the batch into 2 cornies and top up with filtered water and force carb. Always was better than kit kilo back then.

Turned out awesome, most times lol ,so good friends made me put 4 kegs on at their engagement and I did the same at mine, and the kegs got drunk before the package beers I made them buy incase mine were not drunk lol this was 22 years ago before all the science crept in as craft brewing took off.

Goes to show, that there are old ways that still churn out acceptable beers.....
 
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Interesting ghetto backyard experiment lol,

I recently just mashed 2 Aussie lager type beers for the Christmas /New Years hols guests, same receipe, 2 identical batches in 2 grainfathers at the same time, both gravs came out within 1 point or so of each other, 1070, 1071 ish, at 32 ltrs each.High grav mash then diluted down each batch to make about 1048 into the 50 ltr kegmenters. About 45 ltr batches.

Each batch, was oxygen up, pitched with 5 ltr decanted starters of s189, one was run at 14 psi, at 13 degrees for 1 week, then allowed to rise over couple of days to 18. Then carb up and cc, left for 1 week to clear.3 weeks total.

Other batch was run in the other fermenting freezer at the same time, although it started 1 week later because I needed to grow another big starter, ran this one at 20 degrees which is still in the recommended range of this yeast at 13-14 psi. It hit 1012 in 2 days from start of active ferment. Allow to carb up, done in 6 days, cc for 1 week, total of 2 weeks. It caught up with the slower kegmenter .

Drank from both yesterday arvo and the lower temp one was cleaner and more crisp, the higher temp one still clean but there is a difference .
Further lagering in cornies over the coming few weeks will show how they end up.
14 psi was prob not enough to suppress much other than the krausen at higher temp. But I don't want to run higher pressure as I've gone down this pathway to keep oxygen out and to natural carb the brews.

The higher temp run one was done for speed to get stocks up for the holidays and also thought I'd try a side by side test which I'm glad I did, it still turned out really great and my mega swill family will still guzzle it, and most likely will not be able to tell the diff, but I'll still stick with the extra week and get a cleaner result.

So, I'll keep my initial temps down and just accept that time is still key for my fussy lager tastes lol

Cheers
 
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1 week since my beer went into the secondary cube, was a little concerned that I may have introduced O2 by using water pressure to compress the CO2 I had saved and used it for natural carbonation.
Gravity pour from the cube (around about half way consumed) taste is almost as creamy as from my beer engine.
002.JPG 003.JPG

As your experiment with splitting a high gravity wort coldspace I have been thinking over Brads method and I reckon that has potential. A 20 litre batch of beer produces about 1.6 Kg of CO2 on average, more with a higher gravity. Harnessing that CO2 , boiling the water to remove the O2 ,carbonate the water using the reclaimed CO2 and adding that to the wort post fermentation. The only small problem then is getting the O2 out of the head space.
 
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If you fill with water and then push out with reclaimed co2 there will be no head space for 02 the co2 needs to be compressed with a food grade compressor .
 
No, what I did was with a cube of CO2 at atmosphere, start and fill the cube with water at mains pressure, its easier to compress gas than liquid, my only concern was oxygen coming out of the water and mixing with the CO2 which doesn't appear to have happend. At least not sufficiently to oxidise the beer.
 
How much o2 is in mains pressure water and if carbonate does that expel any oxygen .
 
How much o2 is in mains pressure water and if carbonate does that expel any oxygen .
I have ordered a DO meter that is on its way,so soon as I get it I will be able to tell you, at the moment I just know there is some in the tap water. I did read the whole of the Low dissolved oxygen brewing techniques thread very interesting and some things I will be using myself, have been looking at the other sites on line as well. Lots of info here.
http://www.lowoxygenbrewing.com/uncategorized/list-of-brewing-references/
 
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