Cleaning kegs in between batches

[Sadu]

So I just bottled the rest of my first keg so I can move the next batch in.

I would like to do a closed transfer into this keg from a pressurized fermentor.

I was going to take the keg to bits, wash everything, fill the keg with starsan, push the starsan out through the liquid line with CO2, then closed transfer the next batch in.

Then I thought, I already have a keg full of CO2 with next to no oxygen and there can't be that much gunk at the bottom. What if I was to pressure transfer a quart of starsan into the keg, shake it around, push out the beer line and call it good?

Would this do an adequate job of cleaning without having to remove the lid?

 

[IslandLizard]

I've been thinking along the same lines, but never tried it.

There's usually some gunk on the bottom of the keg, sometimes a lot. Although mostly yeast, it will likely contain other precipitate too, such as from fining, hop dust, etc. That will render the Starsan non-effective until you've blown out all the gunk. So maybe fill with a quart or 2 of water, swirl, blow out, do it again until water comes out clear. Then add 1 to 2 quarts of Starsan swirl, shake, roll, whatever, and blow it out.

I always invert the keg over a bucket before all Starsan has been purged, push the gas poppet and pull the PRV to rinse them out with Starsan too.

Right before filling I again expel whatever Starsan has settled (from foaming).

 

[madscientist451]

Then I thought, I already have a keg full of CO2 with next to no oxygen and there can't be that much gunk at the bottom. What if I was to pressure transfer a quart of starsan into the keg, shake it around, push out the beer line and call it good?

Would this do an adequate job of cleaning without having to remove the lid?

It all depends on what was in the keg before, what your definition of "adequate" is and how long the new brew will be in the uncleaned keg.
Was the previous beer cold crashed before it got kegged? Dry hopped?
A funky sour beer? Use a different yeast than the new beer?
How confident are you that "not much gunk" is in the bottom of the keg?
Having said all that, I'll admit that I'm pretty lazy
and have re-used kegs without cleaning them. Most recently I put an American Saison in a keg that previously had a beire de garde with French Saison yeast. In that case, I didn't care if the American Saison picked up some character from the previous beer, I thought it might even add complexity.

 

[Sadu]

It all depends on what was in the keg before, what your definition of "adequate" is and how long the new brew will be in the uncleaned keg.

I'm brand new to kegging so I don't really know what's accepted practice, hence the discussion.

The "old" batch was a schwarzbier, not hoppy at all, and it had been lagering in glass secondary before going into the keg. It was in the keg about 3 weeks before I bottled the leftover, so pretty fresh. As far as gunk goes, I'd say pretty clean since almost everything got left behind in secondary. The last half-pint to come out of the keg was very yeasty though, and brown instead of black, I dumped it - I guess that's normal?

The new batch is a dry-hopped pale ale. Definitely enough flavour to hide a bit of schwarzbier "complexity". It's going to be in the keg 2-3 weeks before I bottle the leftover and make way for the next batch.

 

[Sadu]

So maybe fill with a quart or 2 of water, swirl, blow out, do it again until water comes out clear. Then add 1 to 2 quarts of Starsan swirl, shake, roll, whatever, and blow it out.

Agreed. So the water should clear out most of the yeast/trub and the starsan can sanitize inside the keg and the lines afterwards. All without having to open the keg.

I think this is worth a shot. Cheers.

 

[william_shakes_beer]

Everybody has their own cleaning regimen. Here's mine. When a keg kicks, I pull it out of the freezer, open it up and rinse the entire thing out with clean water to remove the trub, then empty, pressurize and store. When its time to refill, I open it up, disassemble the in and out ports and valves, soaking them in starsan. I put keg lube on all seals, put it back together and fill it up.

 

[billl]

If you haven't seen what is at the bottom of the keg, there is no way I would transfer beer to it. The amount of CO2 needed to purge a keg is really cheap compared to your batch cost.

Personally, I always completely disassemble, clean and sanitize.