Unexpected Fermenting Characteristics

[Renegade]

This thread was almost going to be titled 'Help, My Airlock isn't bubbling" becuase effectivly that's what the subject is about. After about 20 brews through this particular primary main fermenter, a pail-style with a snap-on lid (think Tupperware style), I can confirm that this bugger is very airtight. Comparisons to virgin nuns might be apt.

Each and every brew in the past has delivered the dulcit tones of a Brewer's Opera, the much loved bubbling symphony.(well at least the time I use an airlock, sometimes I dont bother).

Now there's a BUT. - On the latest brew, I reserved yeast from the previous batch (which, it turns out this prior batch wasnt even finished fermenting, its re-krausening in secondary like crazy) and added to the latest batch in question.

Pitching on Saturday, it was only sometime yesterday that I started to get krausen action. Probably no big deal, being that it's winter and I have no applied heat source. The krausen is climing to about three inches, so that's a good sign, and nothing unusual there. I knew the question would come up, so I just took a reading. It's at around 1.0500 from an SG of 1.058. Not much of a drop, but still a drop, and probably a bit slower due to the winter.

So yes, it's fermenting. But there's not been a single peep out of the airlock. I'm not overly concerned, because if for example I was using glad-wrap and observed the above unfolding, I wouldn't give a crap. But I wonder if there's any real reasoning behind it - where is the gas going ? It's gotta be released somehow. Ive checked and rechecked that the lids on, and that the airlock's installed, and I know that the fermenter is airtight.

My only half-baked theiry is that there werent enough yeast cells, and combined with the winter temps it's producing gas a lot slower than normal, the CO2 is seeping out of some micro-leak in the lid because it has more time to release (due to less gas production than usual). Any other theories ?

And this is why airlocks suck. Because as I said, I wouldnt even give it another thought if I was glad-wrapping

This is more a discussion peice than an "Oh My God, Will everything be OK" thread, becuase I'm intrigued as to the sudden changes in what is observed.

 

[discoloop]

Did you make a starter with the yeast saved from the last brew? If not, how long did you leave it between harvesting and pitching?

My gut feel is either
- too long in the fridge between harvest and pitch results in yeast taking a long time to fire
- Brew B (current) is higher gravity than Brew A (previous) and yeast needs to acclimatise before firing off CO2

My airlock can be a bit temperamental. I use it for purely aesthetic reasons (bloop.....bloop) but have learned never to trust it.

 

[Supra-Jim]

IF you squeeze and hold the fermenter, does the water in the air lock stay raised or does it resettle to level?

If it resettles you have a leak, maybe a small one, but that's all it takes.

Cheers SJ

 

[buttersd70]

If the brew is fermenting at a lower temperature than usual (which it sounds, from comemnts you make about winter, to be the case), then you are partially right on your hypothesis.

Firstly, if cooler, the yeast will be working slower...less co2 production.
secondly, if the fermenting wort is cooler, it will retain more co2 in saturation in the solution.

so less co2 produced + less co2 being released from solution = much less co2 coming out of the fermenting wort, and at a slower rate = much more time for slow leak to be evident.

 

[RdeVjun]

A bottle of Snoop squirted around the potential leak sites could highlight a miniscule leak, which is what you're probably having trouble with, IMO.
Snoop is basically a benign detergent that bubbles like crazy from just a film and used to detect gas leaks. Strong detergent solution would achieve the same thing, but may not last as long as Snoop. Link.

 

[Adamt]

I'm not sure what the issue is...

You say the gas must be going somewhere - correct. 8 gravity points is 3-4 times the amount used for priming... if the gas didn't leave the fermenter you'd have an absolute rocket.

Your other theory you say is half-baked - correct, put down the pipe

 

[Renegade]

The yeast was repitched a matter of hours after harvesting, and was not refrigerated. No starter was made.

Batch B is slightly higher, but not a 'big beer' by any stretch

SUpra Jim: Yep, the Water level stays up. Also, I always push down on the lid before I pitch, and get a bubbling from straight air pressure

Butters, the time between batches was a week, and temps haven't changed in a week. So I would have thought they would act similar.

I think you guys might be looking at this as if it's not fermenting vigourously. That's not the case, I personally would say it's going off well (not GOING OFF but you know what I mean). High Krausen is a sure sign I would say. And the gravity has dropped, which while might be a bit small for a yeast pitching three days ago, I consider that it only really started taking off sometime yesterday, so the figures seems right to me.

So I have no doubt that it's fermenting. Which would mean release of C02, I would think. I'm just a bit perplexed about the airlock ! It will all ferment out OK, and with any luck its going to be a fantastic brew, but to me its inexplicable that such activity wouoldnt gets the bubbling started (when time & time again it does).

Lesson to self: Throw the airlock out, and i won't even have these queries, I dont really love using it anyway, unlike some of you guys who get all gooey at the sound of it. but this fermenter's too big for glad wrap (where do I buy commercial wrap, extra wide?)

 

[Renegade]

A bottle of Snoop squirted around the potential leak sites could highlight a miniscule leak, which is what you're probably having trouble with, IMO.
Snoop is basically a benign detergent that bubbles like crazy from just a film and used to detect gas leaks. Strong detergent solution would achieve the same thing, but may not last as long as Snoop. Link.

Nah, it's not that much of a drama for me to go to any lengths to look for leaks. As long as 1. I can make beer and 2. It doesnt get infected is all that really matters. This thread was more a discussion opener than an anguised plea.

And I really dont think there's any leaks (well any more than the last 20 batches fitted with the airlock)

 

[Scruffy]

Give it a stir...


Leave it...


Or repitch a new yeast... what was it? Maybe it's just reprogramming itself to fettle your new wort...