new foam this late?

[manisfive]

I'm five weeks out on this Irish red fermented with notty. I missed my bottling day last week so I was going to do it today. The fermentation appeared done last week. The hydrometer readings were stable and the top of the beer was clear. This week new foam has started to form at the top. Now I'm nervous about bottling today. Any thoughts? Has anybody seen this happen before?

 

[cluckk]

I've seen it happen before with some yeast. Check your gravity. If it's where it should be go ahead and bottle.

 

[winvarin]

I've seen it happen before with some yeast. Check your gravity. If it's where it should be go ahead and bottle.

+1
It's likely just off gassing and not new fermentation. If you subscribe to Brew Your Own, take a look at the most recent issue "BYO University". There is an article in there on carbonation . They include a chart that shows, depending on gravity and temp I think, how much dissolved CO2 there is in beer that's still in the fermenter.

The beer will still continue to release that gas after fermentation is complete. And if the ambient temp of your room fluctuated at all, or you moved or bumped the carboy, it could cause additional gas to come out of solution.

As a side note, this is why airlock activity, the lack of it, or the presence or absence of any kind of bubbles is not a definitive sign that a beer is still fermenting.

 

[manisfive]

I bottled on Saturday. Thanks for the replies.