Gone all cloudy again

[inthedark]

Had to move the barrel on my latest to get better access to the tap - only shifted it slightly, but the beautifully clear blonde has gone back to being murky. Still drinkable, but the dreaded tang has returned.

Apart from avoiding sneezing anywhere near a keg, is there any way of curing this if it happens again? From my notes, I used Muntons Gold yeast as H&G were out of Nottingham, but the product notes say this is a good sticky yeast which should stay down. I did use gelatine fining about 5 days earlier in order to clear it on time (had already been sat for nearly 5 weeks)

[inthedark]

1) If you've moved it to a cold place it could be chill haze. If so it can be moved somewhere warmer (20 deg c) and should clear (try with a small sample first) or leaving it in a very cold place for 2-3 weeks will allow the proteins causing the haze to sediment out. Repeated cooling and warming can cause a permenant haze though.

I did try this to see if it was chill haze, and it doesn't go away. The barrel is in the coldest place in the house, but it's only down to about 17degC during daytime and maybe down to 14 ish overnight. Not sure if that's cold enough to properly clear it?

2) It may be cask frets, there aren't a lot of details available on this but basically they are caused by incomplete fermentation. Air introduced by moving the keg or racking the beer causes fermentation to kick off briefly but there aren't enough sugars to complete the cycle and the yeast gets stuck in limbo. I believe someone reported clearing cask frets by repriming the keg.

I read about cask frets in GW's BYOBRAAH and so have been taking his advice and using injected co2 to purge the headspace after racking, so minimizing the risk of this. Also, when I ran off a couple of pints prior to shifting the barrel, they were crystal clear.

If it was just disturbed yeast though, this should clear very quickly as has already flocculated and just needs to sediment out. Muntons/Nottingham/SO4 are pretty stable yeasts, any disturbance caused by moving the keg should have been minimal.

That's what I'd read too, so I was surprised to have a problem - I thought maybe using the gelatine made the yeast less stable (clutching at straws now).
The other thing I'm wondering about is the note in GW that gelatine has no secondary priming capability - does that mean that using isinglass enables the beer to quickly clear again after it's been moved?

[inthedark]

14-17 is cold enough to clear it without being cold enough to cause a chill haze.

That's good to know, thanks.

If it was sparkling clear before you moved it and it is taking more than a few days to clear again, i'd suspect cask frets (it's happened to me).

OK, I've only given it since Friday night, so I'll keep an eye on it to see if it clears. There's probably not enough left to try repriming, but I'll keep that in mind for next time.

Issinglass is good old stuff when it comes to fining as the cask can be rolled around a few days before before putting onto stillage to redistribute it in the cask and it will fine the beer again. From what Wheeler is saying it appears gelatine doesn't have this capacity.

I might get some in on my next H&G order - lack of space means that I can't always guarantee that I won't have to move a keg, so this property would be useful.

Thanks Chris.