Does a regulator regulate back-pressure too?

Just a quick question. I'm planning to brew, back sweeten and force carb a cider soon. I'm not planning on stopping the yeast with anything other than cold crashing.

My question is:
If a still fermenting keg is attached to a regulator under pressure, will the regulator release the additional pressure generated by the continued yeast activity?

P.S.- I plan to keep this cold anyway while it cabs so I'm not too worried about yeast activity, I was just curious if regulators regulate pressure "both ways"

thanks!

Kindogg said:

Just a quick question. I'm planning to brew, back sweeten and force carb a cider soon. I'm not planning on stopping the yeast with anything other than cold crashing.

My question is:
If a still fermenting keg is attached to a regulator under pressure, will the regulator release the additional pressure generated by the continued yeast activity?

P.S.- I plan to keep this cold anyway while it cabs so I'm not too worried about yeast activity, I was just curious if regulators regulate pressure "both ways"

thanks!

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In my experience, No it will not regulate back pressure. I always store my kegs after carbonating at ~30 PSI to keep the lids sealed. When I get ready to serve from it, I have to release the excess pressure.

your regulator "regulates" the output pressure of a tank Co2 or whatever. if there is too much back pressure it will go back into the regulator. depending on how much back pressure it will blow the relief valve. some ball valves have built in check valves which will prevent any back pressure from getting to the regulator.

thanks for the replies!
I just have a standard corny keg/regulator setup.
Considering that the keg will be at <40 degrees F I'm not too worried about yeast activity anyways.

Out of curiousity, could yeast generate enough pressure to burst a corny keg!?

Kindogg said:

Out of curiousity, could yeast generate enough pressure to burst a corny keg!?

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No.

BrewThruYou said:

No.

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Care to elaborate?

Kindogg said:

Care to elaborate?

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The yeast will get stressed from the pressure and stop way before 130psi.

Kindogg said:

Care to elaborate?

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The main reason is that the pressure relief valve should open and vent the pressure if it gets over ~60psi. If the PRV malfunctions it could create a dangerous situation.

JRems said:

The yeast will get stressed from the pressure and stop way before 130psi.

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Not quite. They become stressed and create some nasty off flavors at pressures over ~20psi, but it takes pretty high pressures to actually stop them. While it only takes ~35 psi to create a toxic environment for yeast, the toxic effects take a long time to be realized, and the yeast will keep producing and building pressure well beyond that before they quit. I've read that saccharomyces cerevisiae cell morphology is unaffected below 50Mpa, which is over 7,000 psi.