Feb 202224Thu

Kegged Citra Smash

SG 1.007 16.9℃ campden tablets kegging SMB wisdom

Having gone in quite heavy on the hops for this recipe I want to make sure the flavour lasts as long as possible, and that means minimising cold-side oxidation. In addition to purging the keg before filling I’m going to have a go at adding Sodium Metabisulfite (SMB) to the keg since some people think it’s good at scrubbing oxygen. Surely worth a go? If I’m happy with the hop retention as I drain the keg over the coming weeks I may well carry out my own A/B test on a future brew. Today however I simply added 0.3g of SMB (crushed Campden tablet) to the purged keg before refitting the lid and purging it again, like the first time by slowly blowing 70/30 into the out-post with the PRV pulled for a couple of minutes.

Pressure transfer method using inline filter

Anyway, the beer was transferred from my Fermzilla to a 19 litre Cornelius keg using the floating dip tube coupled with my finest inline filter, because it’s a double dry hopped brew and there may still be some crud transferred as we get near the end, despite the cold crashing. The filter’s barbed connections coped happily with 12 PSI of pressure on transfer, but I did have to screw the bowl on extra tight as there was some evidence of sanitiser leakage during purging / pressure testing ahead of deployment. I think this is due to the mesh cartridge being slightly too tall for the housing, or the gasket being slightly too thin – either way she wants a good hard twist to make sure everything’s sealed.

Once the 19 litre keg was filled I wanted to put what looked like almost 4 litres of surplus into a mini keg via the post on the collection jar, but although I was fairly careful the trub became disturbed using this method, and went from being settled below the take-off post to getting fairly well mixed with the rest of the brew, which by now had also picked up much of the settled hops from the sloped sides of the vessel. I was going to transfer the murky solution anyway, thinking that I can always crash it out in the keg, but for some reason the flow stopped and I got barely 2 litres. Guessing that this was due to the filter finally being clogged I just binned the rest when I really should have switched to a straight transfer tube, but during clean-up the filter actually looked pretty clear, making me wonder again if it’s worth bothering with if kegging crashed beer. Let’s make a note:

#wisdom: stop using inline filter by default if kegging cold-crashed brew, at least until a concrete reason for doing so arises.

#wisdom: if transferring FV dregs to a mini keg rather than dumping them, use a straight tube (without filter) and don’t worry about trub, which can be cold-crashed out later.

While filling the first 19 litre keg I let it run a tad too long using condensation on the side as my fill guide, and ended up with some liquid coming back out of the gas post near the end. In order to recreate some head space and also give me a sample to measure, I fitted a small tap to the liquid post and filled my trial jar, setting it aside while cleaning up in order for the foam to settle. Even so it was difficult to get a decent reading, because dropping in the hydrometer caused more bubbles to rise in the carbonated brew. Maybe I should have chilled and wetted the hydrometer first? Anyway, I measured a FG of 1.008 (very approximately) at 16.9 ℃ which makes for 1.007, and 5.6% ABV. Happy with that, and extremely happy with the hoppy taste from the trial jar. Let’s hope the SMB does it’s job and we get to enjoy this one for weeks to come!