Why did my airlock go back to bubbling

[Jokester]

I had a 3 week old beer over ferment and the S type airlock seemed to level back out, but a couple days later, instead of going properly level, it started tipping back and bubbling again and got all pushed to 1 side again.
This is an amg over ferment, started with 6.5% abv beer with 1.006 I am shooting to get it to .99 or thereabouts. 1 gal batch started 12/14/19 in a 72 degree house.

Thanks.
Srinath.

 

[bucketnative]

Temperature change? An increase in temperature will cause the gas inside the fermenter to expand and displace the volume in the airlock. Plus, as it warms, CO2 will come out of solution and further displace water in the airlock.

 

[cubalz]

Did you move or bump it? That will cause trapped co2 to come to the surface.

 

[Jokester]

I don't believe I bumped it or moved it or too much increase in temp, but after that airlock started bubbling again it bubbled for 5+ days till it started levelling back today.

In the mean time the other batch that I yeast cake started on 12th is looking like its going flat, I will not be touching it for 8-10 more days at the very least. I'll wait and see if it starts bubbling again too, maybe its what an amg hyper ferment does.

Thanks.
Srinath.

 

[Franktalk]

Is it a saison? If so, it may be the dreaded diastaticus. Saison yeasts have a gene that can cause them to keep fermenting after you think that it has stopped working. This phenomenon has resulted in lawsuits from commercial breweries that have had to recall beers because of bottle / can bombs exploding after sale to customers.

 

[Dland]

One could check with hydrometer and get some data. If it is above 1.010 or so, normal fermentation may have re started for some reason. If it is going below 1.006 or so, it is probably some infection, diastaticus or other, (unless one of the yeasts that are purposefully diastaticus).

 

[kh54s10]

The OP is using AMG to lower the gravity farther than a usual beer would go. Without gravity measurements it is impossible to say whether it is still fermenting or temperature change, atmospheric pressure change, or just something that made some co2 come out of solution.

My guess it that the first part was normal fermentation, a pause, then the AMG kicked in.

 

[Jokester]

Oh amg takes 2+ weeks to kick in ? I thought its pretty fast to start to denature the linkages - but then again its an organic reaction, its always reversible till one of the components has been eaten by another entity in this case yeast.
I used turbo 24 from alcotec but did not put a lot, maybe a teaspoon, presumably the original yeast kicked off the ferment and alcotec 24 took over 2 weeks later when it hit critical mass - no idea. I put very little of the alcotec in to start with, no where near the whole pack I am supposed to use for 5 gal.
So The airlock has gone flat in that "return" beast again.
The yeast caked batch has G13 strain Sweetwater 420 IPA in it and in under 5 days went flat, of course yeast caked means it has nearly 5 packs worth in the bottom with likely 1/2 of that quantity fully revved up, so it rocketed away.

I am yeast caking another 5 gal batch, will post how it goes. It will be eating Pabst extra or some unholy blend of Jai alai and pabst extra.

I start under 1.01 in most of these cases and am shooting for .99 or under. In one set I calculated .989 = 0 sugar, I have got pretty low, pretty much tying abv and sugar in 12 oz - if its 8% its 8gm sugar in 12 oz ,and since I'll be concentrating it 4 fold, likely ending at 2gm sugar. in 1.6 drinks - perfect for my liking.

Cool.
Srinath.

 

[kh54s10]

I'm speculating on the yeast starting then a slow down then more from the AMG. This is because it seems that no gravity readings were taken along the way. So there is no real way of knowing exactly what occurred. It just seems like there was a slow down in the middle. I have never used the stuff and have no reason to try it. I have read a little that says it will keep working slowly for a very long time. I may be mistaken.

 

[Jokester]

I am not sure about taking a gravity reading in the middle, I don't want to introduce air and microbes into it. Is it OK to keep opening it to check it ?
Thanks.
Srinath.

 

[kh54s10]

How long has it been fermenting? I never do anything until at least day 14. I have no experience with AMG, but have read (maybe I misunderstood) that it may keep working at lowering the gravity for a very long time. Months. And that it is risky to bottle beer treated that way as the gravity may drop further than expected causing bottle bombs.

So, in answer, I would not open for gravity readings until you think it is fully attenuated.

 

[Jokester]

One airlock went flat in 4-5 days, but of course that was a yeast cake batch. The other one went flat in about 21 days and about day 24 it restarted. Its now looking like it will level out again.
OK if amg works slow I'll let it run its course and then some. I managed to get a 1.009 measured, Jai Alai to .993 measured in a 5 gallon batch in about 1 month. I have yeast caked the next batch and thrown in 3 types of beer and amg. Wont touch it for a month after airlock stops bubbling. For now I have like 1.5 gal of Jai alai freeze concentrate to keep me company. Anyway Bottle bombs are unlikely, I am freeze concentrating these. Not bottling in glass and waiting for the yeast to work it again. But .993 with a theoretical 0 carb of .987 wont bottle bomb anyway right. I'll let the next set go flat and just wait another month. Lets see what it does, maybe it will restart a few days after flattening out.

Cool.
Srinath.

 

[kh54s10]

Are you just talking about the level of the airlock from one side to the other. That will change constantly with changes in air temperature and atmospheric pressure. I had one sitting and definitely done that sat with one side higher for a couple of months. That really doesn't mean anything.

No experience with AMG so I am guessing in that regard.

 

[Jokester]

Well when it was bubbling I had one side empty obviously. But I thought if the airlock levels out then its done fermenting. Its slowly going from completely on one side to well 2/3 and 1/3rd types in the S tube. The 3 piece ones if the inside cup is tilted then its still working, if inside cup is vertical that means its done right.

Cool.
Srinath.

 

[bucketnative]

Airlock activity should not be used as the sole indicator of fermentation activity. It is a qualitative "eyeball" check only. I have a few fermentation buckets that do not have a complete seal and do not provide much airlock activity at all (only during the height of fermentation). Level of the airlock is also not a good indicator of anything really... it depends on temperature fluctuations, ambient pressure fluctuation, etc...).

 

[Jokester]

This is a glass bottle and its got a tight seal, I pretty much know that, I am so terrified of these things going bad I clan with star sani and boiling water repeated rinsing of everything then the beer all goes in it and the cork etc that was sitting in boiling water is all put on tight. It also sits in the corner in my kitchen without much temp changes in the house, we keep the house at 74 and being by the exterior wall, likely its at 72 the whole time.

Cool.
Srinath.

 

[kh54s10]

Just ignore the level in the airlock, it really doesn't tell you anything useful. Bubbling means there is more gas than the container can hold. After fermentation stops and bubbling stops you can only tell what is happening by taking gravity measurements. As I said it is better to wait longer before taking measurements. The less you open the fermenter the better.

 

[Jokester]

To check gravity and letting it ferment more I'll be putting it in secondary, likely yeast caking the previous batch with another round of warm beer, that way the CO2 from the beer will fill up the air space with co2 and the secondary because I have siphoned it off, there is CO2 being produced that would cover for the exposure. Both airlocks will get boiling starsani, then water boiled and reinstalled.
OK I will do that but I am pretty fine letting it sit another month because all the glass fermenters are full and my plastic gallon juice jug is sitting in the fridge with jai alai etc - cant buy more gallon bottles, no space and SWMBO already is very very sweet letting me use the kitchen corner - trust me we are not in a big kitchen in that house.
Cool.
Srinath.

 

[Jokester]

Jan 12th yeast cake with 1 gal G13 sweetwater 420 strain - measured at 1.01 OG fermented to .998 and this was the bottle that pulled a lot of sediment. Went from OG as wort 1.055, and before amg ferment of 6% abv and 16 carbs to 7.6% and to 6.8 carbs per 12 oz. Now the OG of beer was checked at a higher temp because I had it warming with hot water in the sink. And that was the high sediment bottle. Its going to be freeze concentrated and cold crashed, likely several times till its clear as the original beer.

And 12/20/19 batch of 36oz Red hare and 92 oz Jai alai went to .995. Thats' a bit more math for it. Will calculate that and post back.

Cool.
Srinath.

 

[Jokester]

Redhare+jai alai combo is - 1.0081 OG of beer, 7.21% abv, so it started life as a 1.0621 wort, and amg got it down @.995 which is 8.9% abv and 5.6 gm carbs in 12 oz. I am consistently hitting that 1/2 gm carb per oz.
Now 10 cans of my favorite Double indemnity have gone in gal 1 and 8 pints of G13 have gone on top of what was the G13 batch, all yeast cake, no new yeast was added, 3 drops amg per gal.

Now I know how to get these to drop to their nadir. Put em in and watch the airlock till it levels off, swirl it a few times and if it bubbles again - let it go till it levels back. The sediment and the clearing etc etc occurs very very well. I got a few pics this time, I will try and post it. Vaery good find this amg and it does work on a canned and delivered "beer" as well.

Cool.
Srinath.

 

[Jokester]

This should be calculable. So 64oz of the .995 sg beer got freeze concentrated to 20 oz. The 64 oz had 32gm carbs in it. The max carbs the 20oz can have is that same 32. The max alcohol is 32%. It read SG of .998 and a refractive index corresponding to 30% abv.
Ethanol and sugar raise the refractive index of water but the ratio is over 2.1 grams ethanol needed to do what 1gm sugar will do.
Ethanol lowers the SG of water while sugar raises it. It takes 19 gm ethanol to do what 7 gm sugar will do. Pretty much 2.7 ethanol = -1 gm sugar.
So what would abv and sugar % end up. Still calculating.

Cool.
Srinath.

 

[RPh_Guy]

I have no experience with AMG, but have read (maybe I misunderstood) that it may keep working at lowering the gravity for a very long time. Months.

Where did you read that?
Glucoamylase (amyloglucosidase) action should be finished in a matter of hours.

"Hop creep" can take weeks.

Microbial contamination can take months.

 

[Jokester]

If my calculations are right and my readings are accurate (definitely likely not), I'm barely getting 13% abv as a minimum, of course I am measuring some things near 35F, other things with carbonation, yet others at 72F, 6% by weight sugar which means all the sugar in the 2l is in the melt off - which I know isn't right because the part I am tossing looks awful lot like the base beer and has a monster sediment.
If the white labs abv test doesn't say I am higher than 13% which is pretty pathetic for a beer that started at 9%, I'll drop the freeze concentrate process.

Cool.
Srinath.

 

[Jokester]

Where did you read that?
Glucoamylase (amyloglucosidase) action should be finished in a matter of hours.

"Hop creep" can take weeks.

Microbial contamination can take months.

I am not worried about the speed of amg, but 2 drops will work for 5 gal, that's some powerful enzyme. I wonder if it acts like a scissor basically cut 1 chain, then move on to the next and next and next till its out of starch chains to cut up.

What is hop creep.

Now Microbial contamination taking months, I am basically done with 1 gal in a matter of weeks with the yeast cake. Of course you're talking about a microbe that's not in any of the beers nor is it ec1118 or Turbo 24 (both I added) getting into the yeast cake and the yeast cake getting more and more of it till its all bad.
I already have another interesting situation here too, I have in a few batches added 3 different beers, 1 stout and one pale ale and a different one (I don't remember immediately but it was called Bellringer by RJ Rocker). That + 2 yeasts I added. We're looking at a bunch of different yeasts already aren't we.

Cool.
Srinath.

 

[RPh_Guy]

I wonder if it acts like a scissor basically cut 1 chain, then move on to the next and next and next till its out of starch chains to cut up.

Yep, that's exactly what enzymes do.

What is hop creep.

Raw hops contain enzymes that break down dextrins somewhat slowly, so dry hopping can increase attenuation.

Now Microbial contamination taking months,

I said it CAN take months. It can also take hours or days for a contaminant to affect a batch.

 

[Jokester]

The amg is supposed to be added in the wort or boil. That's 1-2 drops per gallon. I am adding 1-2 drops to beer which has a lot fewer starch in it than any wort, maybe as much as 1/10th in some cases. No wonder this is ridiculously powerful. I am really impressed.

I heard something else from my local beer expert. Does Co2 prevent or slow down oxidation ?
Does high abv prevent oxidation ?

I have never tasted a beer concentrate or even a hyper ferment that I made taste like cardboard. I have had a pine resin taste in 1 beer but that pine resin was there from the start in that beer right out of the bottle. The bottle hadn't deflated either, it was fully carbonated and - the pine resin is intended was my conclusion, I had over a 100 bottles of it, all of them tasted the same.

This is turning into the seinfeld episode where Kramer puts junior mint in the patient during surgery and that fights infection - the surgeon refers to it as "something from above".

Something from above is making these beers not be crap.

Cool.
Srinath.

 

[RPh_Guy]

beer which has a lot fewer starch in it than any wort

No, it doesn't. Beer has the same amount of dextrins as wort in most cases. (There should not be any starch in either.)

Does Co2 prevent or slow down oxidation ?
Does high abv prevent oxidation ?

Only preventing oxygen exposure prevents oxidation, unless maybe if you're using some kind of active oxygen scavenger or the beer is actively fermenting.
The mere presence of CO2 or high alcohol do not prevent oxidation.

"Cardboard" is at the more advanced phase of oxidation.

 

[kh54s10]

I have no experience with AMG, but have read (maybe I misunderstood) that it may keep working at lowering the gravity for a very long time.

Where did you read that?
Glucoamylase (amyloglucosidase) action should be finished in a matter of hours.

I don't know. I guess that I did misunderstand.

 

[Jokester]

These beers are fermenting from the time they go in the gallon, so I guess its active. I have a ton of yeast in these yeast cake batches.
Cool.
Srinath

 

[Jokester]

Oh when the amg has started on the beer which was clear, it turns muddy and cloudy I guess cutting up chains of dextrins makes it cloudy. But by the time fermentation is done, it would be nearly clear again because all the rest has dropped to the bottom. Now would the amg be left active in that sediment, so the next batch takes off just from that amg alone (I guess enzymes don't multiply like yeast. So Likely its a smaller amount in the sediment/yeast cake. Adding more just makes sense. But does it work the way I thought, am I building up amg in the bottle ?
Cool.
Srinath.