Brew-and-serve system idea

[drmouse]

Hi all

Currently I brew 5gal batches in a fairly normal way. Primary fermentation is done in bucket, which is then transferred to a corny. I force-carb lagers, while I naturally carb ales. These are then served through a tap or a beer engine.

I have been thinking for a while of a more "efficient" and natural way of doing this, and I have a cunning plan. The idea is to use captured CO2 only, which is both cheaper than buying it and fits with the CAMRA philosophy. Please let me know your thoughts on it.

Stage 1

Stage 1 is fermentation. This will be done using the following setup:

The wort is in Corny A. Corny B is filled with water. The gas ports on each corny are connected, and the liquid port on Corny B is connected to a hose which runs into 5gal bucket C. As the wort ferments, the CO2 passes into B, which pushes the water out into C. Once all water has been expelled, excess CO2 will bubble through the water, creating an airlock.

Stage 2

Stage 2 is racking, and would probably be done shortly before fermentation is complete.

The gas lines and liquid lines of both cornys are connected together, then the beer is allowed to syphon into B from A (which will probably require getting it started with a slightly higher pressure in A before connecting the gas lines). As it does, the CO2 in B will flow into A.

Stage 3
Stage 3 is secondary fermentation.

A is already filled with CO2, and B contains the beer. If we transfered before fermentation was complete, this should still be fermenting nicely. If not, we would need to introduce some priming sugar, and much more than normal (as we need to build the pressure in A as well as just the head space).

D is a pressure gauge, and E is an adjustable pressure relief valve. The pressure should build and then be maintained at the set point (I know there may be leakage as conys are designed to maintain a seal under pressure), carbonating the beer as desired. Once this is complete, the beer should be chilled to the required temperature and allowed to settle. I would expect the pressure to drop a little once secondary fermentation is complete. The gas lines can be separated and D & E removed at this point.

Stage 4
Stage 4 is the tasty bit: Serve the beer.

Here, we use the collected CO2 in A to fill the headspace in B as we serve, keeping the ale fresh. There should be just the right amount. For ales, this wants to be done at about atmospheric pressure, so my proposed setup is:

Bucket C is filled with water and connected to the liquid line of A (either through a tap at the bottom or a hose down to the bottom, preferably with the syphon started). The bottom of C should be above the tap (possibly below if it's a beer engine, I have found they sometimes leak). As you draw beer, CO2 will be drawn into the headspace of B from A, and water will flow into A from C.

For lager, we need to maintain a higher pressure than we can (easily) get from a simple water head, so I propose:

Instead of a bucket of water, the liquid line of A is connected to a water pressure regulator (F), which is connected to mains water pressure (G). Adding the pressure gauge back in between A and B would probably be a good idea. Again, CO2 flows from A to B as beer is drawn, and the space is filled by water, this time at a set pressure reduced from the mains.

So, that's it. Thoughts? Suggestions? I know it's complicated, but it seems like a fun project!

 

[Cwrw666]

Initial thoughts - you are insane.:lol:
What about - connect the FV to another via a pipe that connects to the bottom. The second FV will fill with CO2 as the brew ferments, pushing the air out of the top. Then use this CO2 connected back to the top of a pressure barrel (not presurised) and dispense beer via a pub beer engine. As the beer is pulled from the PB, CO2 is drawn in (instead of air as would be normal in a pub) so the beer will be just like you get in a pub, but it doesn't matter how long long you take to drink it all as no air comes into contact with it.

 

[drmouse]

I'm not insane, my mother had me tested! :sulk: lol

I had thought about that, but the problem is that the CO2 comes in contact with the air, which could mean infection getting in. Using an air lock (basically the water in the second vessel and/or bucket) reduces the chances.

The system I describe means the brew never comes into contact with the outside world except when it comes out of the tap. There is minimal chance of infection and it won't go stale.

I wouldn't rely on the whole "CO2 is heavier than air" thing. CO2 will still disperse, otherwise we would be unable to breath at the surface of the earth.

Thinking about it, for ale, you wouldn't need to do secondary fermentation with both cornys connected. All you need is 1 corny's worth of atmospheric pressure CO2 to pull through.

 

[Cwrw666]

"I wouldn't rely on the whole "CO2 is heavier than air" thing. CO2 will still disperse, otherwise we would be unable to breath at the surface of the earth."
Yes, instead of collecting it in a second FV you could collect it in a flexible plastic bag. That would work surely.

 

[drmouse]

Actually, for ale that would work. It's for lager where it wouldn't. The co2 needs to be at pressure, and applying that pressure to a bag would be difficult. The best way I could see would be to put it in a pressure vessel and pump air in outside the bag. That ends up being just as complicated in the end, though.