Tomorrow is the Big Bottling Day. I snuck a peek about a week ago and took a hydro reading, and all is well I believe. I took another peek today (14 days in) just to make sure I'm not about to bottle a mess, and I just wanted some confirmation that what I'm seeing is ok (and not symptoms of mold or contamination), considering the difference between last pic and this pic.

Here's ~7 days into it: http://www.flickr.com/photos/rgoodwin/6932711321/in/set-72157629461259769

Here's today: http://www.flickr.com/photos/rgoodwin/6949595183/in/photostream

There was some temperature fluctation, but I've tried to keep it no higher than 72. In the past couple of days I got it down towards 69...maybe it's some renewed fermentation?

When I pull the lid on the pail, I definitely get the "whoosh"/hiss sound of CO2 coming out.

Thanks for your advice!!

Update: Bottling is done!

Pictures at: http://www.flickr.com/photos/rgoodwin/sets/72157629148787580/

FG is right at 1.011, with the acceptable range being 1.010-1.012.

When I opened the primary this time, there was no "whoosh" or feel of air escaping. Also it seems all the big bubbles were gone and down into a ton of tiny bubbles. They dissipated quickly while racking to the bottling bucket. That makes me pretty hopeful it's not a solid (like a mold or yeasts still stuck together etc.).

Samples smell like a perfect ale. Taste tested by 3 people, all found it tasty, if not particularly "complex". I know the carbonation/conditioning process can change the flavor characteristics...

Got 21 22oz bottles full, and about 5 normal size to be "flavor/carb check" victims. About 1/2 gallon left in the bottling bucket when we stopped; it just had too many solids and I didn't have a proper screen or way to filter them. It's definitely starting to become clear the advantage of a secondary to help refine/filter, or at least trying to filter while going to bottling bucket.

Whatcha think guys?

2 Answers 2


It basically looks completely fine to me. From the pictures its impossible to tell if its contaminated. As long as your sanitation was good before the wort went in, and you kept it closed for the first 7 days, I am sure its fine. If the temp has been swinging a little bit its normal for the bubbles on top as CO2 is trying to escape as it got warmer.

If your gravity is steady now you are probably good to go for bottling.

  • I don't know if it's bad etiquette to upvote competing answers, but I'll try :) I'll probably start in about 6 hours, so let me know any and all other things to look for. See my response above for a bit more detail. Another nuance: it was pretty warm for the first day or so, because I didn't know yet about the 5-10 degree bump from fermentation heat, so someone told me that I could have burned through a ton of the yeast at first and left some of the stubborn guys around to work and produce CO2 later. Anyway, I'll lay (clean) hands on later, and already got a carboy for next time to WATCH :)
    – goodytx
    Mar 4, 2012 at 14:34
  • Ok I see, I can upvote both and then choose the answer. I guess that will happen at tasting, or if bottles don't explode for a few days ;)
    – goodytx
    Mar 4, 2012 at 14:37
  • It's fine to vote for all answers you think are useful. I also agree with brewchez, it could be nothing, but it does look similar to how my contaminated batches looked last year. It is hard to tell from the photo, which is why I wrote that I wasn't 100% sure. It could go both ways!
    – mdma
    Mar 4, 2012 at 14:41
  • Complete side note: just read about a guy that puts a sample into a plastic water bottle and "scrunches" the bottle up, so that he can see the effect of carbonation over time and avoid bombs. Interesting!
    – goodytx
    Mar 4, 2012 at 15:23
  • Updated above; not sure if I have to post a comment here for you to be notified :)
    – goodytx
    Mar 4, 2012 at 23:09

There's good news and bad news here. The good news is that if you bottle your beer tomorrow and drink it within the next few weeks, then it should still be ok, maybe with a touch of sourness.

The bad news is that does look like contamination. Your photo mentions "flavor bubbles". Often there are fine bubbles from the CO2, like in your first photo, but not as large as those in the second photo. Contamination sometimes produces a film (pellicle) on top of the beer which traps the CO2 to produce large bubbles.

I would bottle in plastic soda bottles rather than glass just to be on the safe side, since we don't know what the cause of the contamination is. (If pushed to guess, brettanomyces.) If it is still fermenting, you'll end up with bottle bombs. The bubbles could be renewed fermentation, but not by the yeast you originally pitched.

I'm surprised you're getting a "CO2 whoosh" when you open the bucket - are you using an airlock? With an airlock there isn't any significant pressure difference inside the bucket that would cause gas to rush out.

I've had a very similar thing thing happen about 6 months ago to 4 batches. I'm guessing weak yeast, and opening the fermentor too often was the cause of my contamination.

Nothing harmful can grow in beer, so don't be afraid of at least tasting it, and hopefully bottling it.

  • To be honest, I'm not 100% sure about this - brett takes a while to get going, and the bubbles seem on the delicate side. It could just be CO2, but I've never seen that much bubbles after 14 days for a regular beer.
    – mdma
    Mar 3, 2012 at 20:57
  • If bottle bombs are a concern, couldn't he just refrigerate the beer after it's done carbonating? This way, he wouldn't have to get new bottles. Mar 3, 2012 at 21:15
  • Not really, since the pressure builds up during fermentation, and it's then the bottle will explode, so chilling after carbonation is too late. The problem is knowing how much pressure will be produced and if it's less than what the bottle can take.
    – mdma
    Mar 3, 2012 at 21:21
  • Its perfectly fine to chill the bottles once the carbonation is at a good point. The bottles can handle more pressure than you think beyond normal beer carbonation. Its not hard to "catch" the right point if you crack one open every couple days, then chill the entire batch. Wild contamination is stunted more easily than normal brewers yeast by the cold temps. I am not a fan of hanging on to something I think is contaminated, but for the newer brewer every batch is precious. If one suspects contamination, chilling is perfectly fine way to prevent bottle bombs.
    – brewchez
    Mar 4, 2012 at 3:05
  • I'm not sure how best to respond (new SO poster, long time reader :) ). So I'm going to respond here briefly, and to brewchez below. In summary: crap. I'll test and taste and let you all know. The local brew store guy said he thought it looked fine, but who knows...the temperature comment caught my eye and reminded me that it DID swing high temp for a few days, like 73'ish, so @brewchez comment does sound quite realistic. Besides flavor, which I expect (from my very short Mr Beer experiments) to be flat, unrefined, and hoppy, is basically "sour" the other characteristic I should test for?
    – goodytx
    Mar 4, 2012 at 14:29

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