Possible infection? Safe to bottle...?

[squirt in the turns]

I've got an Ale in secondary at the moment that I made on 25/04/09. I racked it on 04/05/09, which may have been a bit late, but I think I may have just about caught it before it stopped fermenting completely. Racked with a bit of dex and 20g Cascade pellets. I've kept the temp around 20 degrees in primary and lower after the first couple of days in secondary.

Since racking a sort of a minor krausen has formed on top of the brew - just a very thin layer of beige foam. It hasn't really subsided, and the water levels in the airlock are not equal, so there appears to be positive pressure inside the fermenter (although it's not bubbling). I've been meaning to taste it and take an SG reading (will try to do that tonight). It does smell fine.

I'm worried it might be infected as it surely can't still be the yeast that's active? If I bottle now am I likely to have a load of bombs on my hands? Is it possible it's just a surface infection that won't find its way into any of the bottles except the last few?

Ingredients were:
1 x Coopers Real Ale
1kg Brew Enhancer 1
350g LDME
20g Northern Brewer Hops @ 15 mins
7g Northern Brewer Hops @ 5 mins
Added a sachet of Morgan's ale yeast to the last few mins of boil as nutrient.

Start SG: 1048

Any advice would be much appreciated.
Cheers!

[timmy]

Hi,

Does it smell funny? That's generally a better indicator of infection than just a krausen.

Cheers,

Tim

[billybushcook]

Slight "rainbow" colours in the Krausen ?
Slight "skin" on it ?

Mick.

[drsmurto]

When you racked it you will have roused the yeast up and its back in action.

Sounds perfectly ok to me altho i would be checking SG daily to make sure it has finished fermenting completely before bottling it. When you take SG readings take the opportunity to taste it. I take up to 10 samples over the course of each batch.

[squirt in the turns]

Hi,

Does it smell funny? That's generally a better indicator of infection than just a krausen.

Cheers,

Tim

Nope, smells fine as far as I can tell. Nice and hoppy. It's only my eighth brew, though, so I may not be as sensitive to the telltale aromas of an off batch as some of you guys. I also have a cold right now

Slight "rainbow" colours in the Krausen ?
Slight "skin" on it ?

Mick.

No psychedelic krausen and no skin that I can see.

[squirt in the turns]

When you racked it you will have roused the yeast up and its back in action.

Sounds perfectly ok to me altho i would be checking SG daily to make sure it has finished fermenting completely before bottling it. When you take SG readings take the opportunity to taste it. I take up to 10 samples over the course of each batch.

Cheers, Doc, I'll sample it tonight and over the next few days and bottle if the SG is stable. If it rises to and stays at ambient temp (around 22-23) during this time, is it likely to develop off flavours? It's just that in order to take a sample I have to remove the airlock and lift the fermenter out of its water/ice bath - bit a pain (yeah, I'm lazy). I'd rather just take it out and leave it out until I bottle.

[drsmurto]

What yeast?

I like to raise the temp in the last few days prior to racking. As high as 24C which helps clean up any by products (diacetyl etc)

[warra48]

He used a sachet of Morgan's Ale yeast (see original post).

Sounds all OK to me.

My last brew with WY1968 was in primary for 2 weeks. I thought it had finished, as it was down to 1.013 SG. Placed the fermenter in the fridge for 2 days to drop the yeast out. Took it out again, and it came back up to about 20ºC. Circumstances prevented me from bottling for another week, but during that week it had dropped to 1.010 SG.

The point is that after the initial vigourous ferment, most yeast will continue to slowly work away for a while longer, and can generate some further kraeusen. Raising the temperature at that stage will not give you off flavours, as fermentation is virtually complete by then.

Once you get consistent FG readings over 2 or 3 days, you should be right to go.

[squirt in the turns]

Cheers Warra and Doc. The yeast was Munton's Premium Ale Yeast (sorry, omitted that from the original post). The Morgan's stuff was just added to the boil as nutrient.

I'll give it a few days at ambient temp and take the readings as I go. Do you think I can expect the krausen to fall and disappear? I'd prefer to have all the crap floating on it settle out rather than get stirred back in when I bulk prime it (or doesn't it matter? It has loads of hop bits stuck in it).

[warra48]

You could try to drop the kraeusen by cold conditioning your beer for a few days.

Personally, I wouldn't worry about it. If you don't disturb your fermenter too much at bottling time, it will gently settle onto the trub/yeastcake as the fermenter empties.

I've done exactly that with most of my brews, and I have no trouble getting clear beers once they are bottled conditioned.

[Pale_Ale]

Infection is fairly unlikely by the sound of things. How much dex did you rack with it? The krausen is just the yeast's way of saying thank you for the extra sugar. It will die down.

I would just give it another week in the secondary, it's only going to improve it.

[squirt in the turns]

Cheers guys. I racked it with a few spoonfuls of dex, not much I think. Having tasted it I don't think it's infected either.

I can't cold condition in the fermenter as I don't have a spare fridge

I'll just give it another few days and pour the bulk priming solution in very gently.

[drsmurto]

Rack it to another fermenter when bottling - this way the beer mixes with the priming sugar thoroughly and you leave behind the extra yeast.

If you add it to the fermenter and stir gently to avoid mixing up the yeast which has settled you wont mix the sugar in effectively which means some bottles will be overprimed, others underprimed.

[Pale_Ale]

Yeah, best not to mix up the trub especially for a lager where you want as much clarity as possible.

I have tasted beers which have been bulk primed using this method (not one of mine), and it is not bad but definitely on the cloudy side. It's one of those where you've invested so much time already, it's worth doing properly.

[Bizier]

And siphon from the top, not the tap if you can. This allows you to tilt at the end and get the last clear beer without sediment.

I use a little bit of sanitised tubing that fits in the end of my racking cane, once I get a siphon going with my mouth, I move the racking cane to slightly above the level of beer in the fermenter and whip out the bit of tubing from the end, so the beer will never touch where my mouth has been (and only inhale, don't exhale).

The little piece of tubing is actually from a "little bottler" that a valve part was lost down the sink.