Fermentation Start/Stop/Start?

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mygar

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Hey guys, I have two 1 gal batches (saison, witbier) currently fermenting. Recipes for both called for fomentation @ 65F for 14 days. At day 10 … it seemed both beers were pretty much done. Krausen fallen back into beer, no bubbles in airlocks... little if any bubbles seen in carboy, etc.

I went ahead and added some gelatin to both to help clear the beers (probably not needed too much with these style, but why not?). After a day, you definitely could see the proteins drop out of beer by clinging to sides of carboy and adding to the bottom.

But curiously, fermentation seemed to have picked up a bit in one of the beers with some light bubbles forming at top of beer and in airlock. Is this normal?

Also, I debate using gelatin … it definitely seems to help clearing the beer .. but I wonder if exposure to oxygen is worth it. I have to remove the stopper to add it... and gently swirl the beer to help mix it in a bit. Thoughts?
 
I see it too, I figure there are a few possible reasons - there may yet be a little fermentation to be done, maybe I stirred up a little unfermented wort or super happy yeast that hadn't met yet, or that I'm simply releasing Co2 that's in the beer already - it's not carbonated exactly in the traditional sense but it may be there.

I'd avoid any vigorous splashing and such but I think pouring in gelatin and gently stirring shouldn't be a big deal. There's probably a layer of C02 in there, or your carboy / fementer / bucket / etc. is head space is even quite full of it. Some stirring isn't really brining much beer to the surface to join with any O2 that may or not be present. Good habits are good, but a quick pour and stir, for me at least, = no problem.
 
It might be the beer degassing the c02 from fermentation.

If you have a hydrometer it's always best to take a gravity reading to see if fermentation is done rather than relying on airlock activity. If you're worried about losing volume from checking the gravity with only having a gallon then just wait out the full recommended fermentation time before fining or packaging. Judging by the krasen is a good way to tell if primary fermentation is complete but the yeast still have clean up work to do.
At 10 days, depending on the temperature, SG, and type of yeast, the yeast could have still been cleaning up and not totally finished when the gelatin was added.

I have never used any finings and I get pretty clear beer with just time and cold temps. I try to keep my beer away from oxygen as much as possible but I'm by no means obsessive about the exposure when it's part of the process. I know some people worry a lot about it and swear by their process and that's just fine. This hobby is about doing what works for you, the brewer.
 
It might be the beer degassing the c02 from fermentation.

If you have a hydrometer it's always best to take a gravity reading to see if fermentation is done rather than relying on airlock activity. If you're worried about losing volume from checking the gravity with only having a gallon then just wait out the full recommended fermentation time before fining or packaging. Judging by the krasen is a good way to tell if primary fermentation is complete but the yeast still have clean up work to do.
At 10 days, depending on the temperature, SG, and type of yeast, the yeast could have still been cleaning up and not totally finished when the gelatin was added.

I have never used any finings and I get pretty clear beer with just time and cold temps. I try to keep my beer away from oxygen as much as possible but I'm by no means obsessive about the exposure when it's part of the process. I know some people worry a lot about it and swear by their process and that's just fine. This hobby is about doing what works for you, the brewer.

Yes, don't want to check gravity @ 1 gallon and lose beer! So, I have making sure to give it plenty of time in fermenter.

Im not sure what the rule is for adding finings to the fermenter. Are you supposed to wait when fermenting is all complete? The directions I have on the gelatin packet say add 2-5 days before transfer from fermenter.
 
I see it too, I figure there are a few possible reasons - there may yet be a little fermentation to be done, maybe I stirred up a little unfermented wort or super happy yeast that hadn't met yet, or that I'm simply releasing Co2 that's in the beer already - it's not carbonated exactly in the traditional sense but it may be there.

I'd avoid any vigorous splashing and such but I think pouring in gelatin and gently stirring shouldn't be a big deal. There's probably a layer of C02 in there, or your carboy / fementer / bucket / etc. is head space is even quite full of it. Some stirring isn't really brining much beer to the surface to join with any O2 that may or not be present. Good habits are good, but a quick pour and stir, for me at least, = no problem.

Yes I considered that stirring up of wort might have triggered more fermentation. I gently swirled the beer in carboy briefly and gently after adding gelatin, as I don't have a appropriate sized spoon to fit in the carboy. So improvised really.
 
Yes, don't want to check gravity @ 1 gallon and lose beer! So, I have making sure to give it plenty of time in fermenter.

Im not sure what the rule is for adding finings to the fermenter. Are you supposed to wait when fermenting is all complete? The directions I have on the gelatin packet say add 2-5 days before transfer from fermenter.
Honestly I've never understood the point in adding it when the beer is still in the primary but I've never done it myself. Every time I hear someone adding gelatin its always to a keg then the first pull is just a dumper.
 
Honestly I've never understood the point in adding it when the beer is still in the primary but I've never done it myself. Every time I hear someone adding gelatin its always to a keg then the first pull is just a dumper.

Yep... not sure whether I should be adding this way or not. Maybe other folks can chime in? I hope I am not adversely affecting fermentation. Gelatin is just supposed to drop proteins right... and not adversely affect sugars.
 
Yep... not sure whether I should be adding this way or not. Maybe other folks can chime in? I hope I am not adversely affecting fermentation. Gelatin is just supposed to drop proteins right... and not adversely affect sugars.
It's supposed to drop anything in suspension like trub, yeast, etc. So, as far a I know, you're supposed to add it after fermentation is completely over. It shouldn't affect the sugars other than taking the yeast away from any work they weren't finished with.
 
Hey guys, I have two 1 gal batches (saison, witbier) currently fermenting. Recipes for both called for fomentation @ 65F for 14 days. At day 10 … it seemed both beers were pretty much done. Krausen fallen back into beer, no bubbles in airlocks... little if any bubbles seen in carboy, etc.

I went ahead and added some gelatin to both to help clear the beers (probably not needed too much with these style, but why not?). After a day, you definitely could see the proteins drop out of beer by clinging to sides of carboy and adding to the bottom.

But curiously, fermentation seemed to have picked up a bit in one of the beers with some light bubbles forming at top of beer and in airlock. Is this normal?

Also, I debate using gelatin … it definitely seems to help clearing the beer .. but I wonder if exposure to oxygen is worth it. I have to remove the stopper to add it... and gently swirl the beer to help mix it in a bit. Thoughts?
In your post you do not mention cooling your beer to at least below 50f, the colder the better. Gelatin works best when the beer is cooled so if your beer does not drop perfectly clear, dropping the temp next time may help.

Regarding oxygen exposure, it is for this reason that I do not fine with gelatin as it requires a cold crash prior to kegging (or fining in the keg, which I do not want to do for other reasons) which will suck back air unless you have a means to have it suck back C02. Many brewers use Mylar balloons filled with CO2 as an approach to address this issue with good results.
 
In your post you do not mention cooling your beer to at least below 50f, the colder the better. Gelatin works best when the beer is cooled so if your beer does not drop perfectly clear, dropping the temp next time may help.

Regarding oxygen exposure, it is for this reason that I do not fine with gelatin as it requires a cold crash prior to kegging (or fining in the keg, which I do not want to do for other reasons) which will suck back air unless you have a means to have it suck back C02. Many brewers use Mylar balloons filled with CO2 as an approach to address this issue with good results.

Yes I have read that it is best to use with cold crash, but admittedly am in bit of a rush... having a supply problem :). Gearing up to brew 2.5 gal on a regular.

I have read gelatin still works at higher temps, just takes longer. Here is a pic... notice the proteins cling onto side and dropping to trub. This started happening within 24hrs of adding gelatin.
20200918_131107.jpg
 
My concern is if fermentation was not complete and dropping yeast out of suspension.

Next time I will wait full 2 weeks ...

My next brewing purchase I think will be a Foundry 6.5. Also, looking at the Flex + from spike. The flex + looks ideal for my needs, cold crash, pressure transfers, etc.
 
Some light reading from Brulosophy. I typically fine with gelatin, usually while transferring to keg. If I’m bottling then a small batch I sometimes add gelatin a few days prior at ferm temps.

of the times I’ve fined after cold crashing, it was still in the fermentor (and yes, got suckback) but having it colder does seem to help. My current method is to xfer to purged keg, purge again, chill on gas,add fining and purge again. Takes 2-3 days to really clear up. By day 5-6 the keg is clear carbonated except for the first pour or two.

As to your fermentation question, I ferment in a mini fridge the same as it appears you are. When you open the door most of the cold air falls out and is replaced by warmer air. I’ve had my airlock start slowly bubbling a few times. Almost positive it was off gassing. Checking FG produced no movement a day or two later. Also if you don’t have a fan in there, I highly recommend one. I just use a cheap 120mm PC fan with bolts for legs. Greatly helped to even out the temps
 
Some light reading from Brulosophy. I typically fine with gelatin, usually while transferring to keg. If I’m bottling then a small batch I sometimes add gelatin a few days prior at ferm temps.

of the times I’ve fined after cold crashing, it was still in the fermentor (and yes, got suckback) but having it colder does seem to help. My current method is to xfer to purged keg, purge again, chill on gas,add fining and purge again. Takes 2-3 days to really clear up. By day 5-6 the keg is clear carbonated except for the first pour or two.

As to your fermentation question, I ferment in a mini fridge the same as it appears you are. When you open the door most of the cold air falls out and is replaced by warmer air. I’ve had my airlock start slowly bubbling a few times. Almost positive it was off gassing. Checking FG produced no movement a day or two later. Also if you don’t have a fan in there, I highly recommend one. I just use a cheap 120mm PC fan with bolts for legs. Greatly helped to even out the temps

Thanks for the link. I have not considered a fan but that makes sense. Will look into that. Yes, I am guilty on opening fridge to look at the carboys. Being new to this, I guess its pretty common :)
 
The study comparing adding gelatin at yeast pitch vs cold crash was interesting. Little difference it appears. If oxygen is a concern, it would seems ideal to add it at pitch. Especially with small volume batches? I would suspect small volume batches are more susceptible to oxygen.
 
Yes, I am guilty on opening fridge to look at the carboys. Being new to this, I guess its pretty common :)
I’m not sure anyone checked their fermenter as often as I did my first batch. Oxidized to hell. It was great. 2nd brew was much better. Let it work for 2 weeks undisturbed. Checked gravity once, it was on the money and bottled right after.
 
Yes, don't want to check gravity @ 1 gallon and lose beer! So, I have making sure to give it plenty of time in fermenter.
Definitely don't want to use a hydrometer for 1 gallon batches. Grab a refractometer and a wine thief. Only need to take a few drops from the carboy to measure the gravity/brix. Just gotta remember that the alcohol skews the reading, but there are some data/equations/curve fittings to adjust for it out on the internet. This is how I measure for FG.

Gearing up to brew 2.5 gal on a regular.
I just upped my brews from 1 gallon on the stove to doing 2.5-3 (did my first batch last week). I'd say definitely worth it just based on the inputted effort to beer output (especially if wanting more beer on hand). I also contemplated one of those all-in-one anvil brew doo-dads, but I opted for getting a 10.5 gal SS brewtech kettle (room to expand to 5gal) and a propane burner. I just don't like the idea that if one thing breaks on the anvil then you're SOL.
 
The study comparing adding gelatin at yeast pitch vs cold crash was interesting. Little difference it appears. If oxygen is a concern, it would seems ideal to add it at pitch.

I find it fascinating that, given the fact that gelatin strips yeast from the beer, final gravity pictures for the two beers are not shown. Normally there are pictures of the two hydrometer readings. And if you read the comments, it's apparent that originally there were pictures of the FG readings, which someone called BS on, in that they looked like the same sample. Then, apparently, the pictures vanished.
 
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Saw that. Seemed fairly well explained by the photo editor. I was more interested in the fact the the gelatin used didnt produce a clear beer even though he fined after cold crash. Looks like the LD Schott gelatin is not the way to go.
 
I find it fascinating that, given the fact that gelatin strips yeast from the beer, final gravity pictures for the two beers are not shown. Normally there are pictures of the two hydrometer readings. And if you read the comments, it's apparent that originally there were pictures of the FG readings, which someone called BS on, in that they looked like the same sample. Then, apparently, the pictures vanished.
Whoa not good
 
Ok this is day 14 and this beer... like I said looked like it was all done at 10 days. After adding gelatin it appears to kick start again. This is what it looks like... is it off gassing? Should I bottle?
20200919_193552.jpg
 
It was bought at brew supply. Label says grade 1.

just thought i'd make sure it wasn't jell-o mix... ;)

edit: someone else would have to answer if protein is a yeast nutrient?

edit #2: dorkin' around on google, yeast can use it for nitrogen, so it'd be like adding DAP maybe.....
 
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It was bought at brew supply. Label says grade 1.
Highly recommend knox unflavored gelatin. Works great and likely cheaper.

@VikeMan Do you have a link I could read up on. I have a hard time believing gelatin strips yeast. I have added gelatin to the bottling bucket with priming sugar and bottles carbed up with no issue. My understanding was that it grabs onto proteins in suspension.
 
@VikeMan Do you have a link I could read up on. I have a hard time believing gelatin strips yeast. I have added gelatin to the bottling bucket with priming sugar and bottles carbed up with no issue. My understanding was that it grabs onto proteins in suspension.

Here's one:
Alternatives to Isinglass for Beer Clarification
Walker et al., in Journal of the Institute of Brewing
https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.2007.tb00761.xSee the "Discussion" on page 350. Basically, gelatin is positively charged, so it attracts negatively charged yeast.

This is also interesting... "Yeast" by White and Zainasheff mentions on page 111 (in the context of yeast finings) ...
"While gelatin is an alternative fining agent, it is not as effective as isinglass."
(The above appeared after a warning that isinglass might result in too few yeast to carbonate.)
I strongly suspect this quote contains the reason you are able to bottle carb after using gelatin. i.e. gelatin is stripping some of the yeast, but leaving enough to carbonate.
 
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