Degassing in primary-- DEBUNKED.

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Neeb

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I keep seeing different, dare I say, "opinions" on degassing because some say not to until secondary and others say to do it in primary.

Anyway just a few questions, is it possible for enough of the co2 to build up in the must that it totally annihilates all the yeast and stops fermentation? The container would probably have to.. maybe be completely sealed although for this to happen, right? It's not going to happen with an airlock is it? What if the air lock gets clogged with foam while you are away, letting co2 out but not as much as usual. As long as it doesn't build up actual pressure and the co2 can still escape, is it really that huge of a deal for the yeast? Also I am not asking about the taste although I would not mind that input, I am just asking for the sake of the yeast being as healthy as possible.

Imagine if you had a perfectly clean room just for fermentation where no organisms or bacteria could possibly exist (just hypothetical.) Would it be better to just not even have an airlock in that case and just leave the lid open (,if there was no oxygen of course.)

Anyway side note, I started 2 wines 43 hours ago. One was pitched slightly more yeast and at the top on the sides of the container there is way more bubbly foam (on just the one with more yeast.) I am wondering if I should stir it around a bit so that the foam sinks into the wine instead of maybe drying out and sticking. Thoughts?
 
i would say it depends on the yeast being used and the OG. if it is a "small wine" i wouldnt worry. fermentation temps also bring in a facture as cooler temps the must will hold c02 in solution. I have done some mead at the 14% range and swirled the bucket for the c02 to escape. as for taste i have no knowledge. degassing is for complete fermentation.
 
Thank you kindly! I just realized another question I have for anyone that would like to help enlighten. I read somewhere that under-pitching and higher temperature (both on their own) can result in a higher ABV...
 
A confusing thread title. When you debunk something, you usually provide some references to experimental findings, research papers, etc. You seem to be asking a question.

The motivation for degassing in primary is to release CO2 in order to lower the carbonic acid level and therefore keep the must pH slightly higher. Low pH is one of the sources of yeast stress.
 
Bobby_M said:
A confusing thread title. When you debunk something, you usually provide some references to experimental findings, research papers, etc. You seem to be asking a question.

The motivation for degassing in primary is to release CO2 in order to lower the carbonic acid level and therefore keep the must pH slightly higher. Low pH is one of the sources of yeast stress.
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And the co2 level builds up again in about no time during active fermentation, that's why I call degassing bollocks!

But what is also done during "degassing" is actually rousing the yeast and that has quite a positive effect on the fermentation.

So at the end, it's just the wrong word and idea behind something that actually provides benefit.
 
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Miraculix said:
And the co2 level builds up again in about no time during active fermentation, that's why I call degassing bollocks!

But what is also done during "degassing" is actually rousing the yeast and that has quite a positive effect on the fermentation.

So at the end, is just the wrong word and idea behind something that actually provides benefit.
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Heh, we keep agreeing on the mead/wine stuff.

Degassing is not needed. Excess CO2 escapes and leaves the airlock. If you degas and take out some CO2 that'll just be put back by the yeast in a few minutes won't make any difference. I have made batches with and without degassing. I believe the ones without came out better, probably because I'm not opening the fermenter and forcing O2 into the mead two to three times a day.
 
Toxxyc said:
Heh, we keep agreeing on the mead/wine stuff.

Degassing is not needed. Excess CO2 escapes and leaves the airlock. If you degas and take out some CO2 that'll just be put back by the yeast in a few minutes won't make any difference. I have made batches with and without degassing. I believe the ones without came out better, probably because I'm not opening the fermenter and forcing O2 into the mead two to three times a day.
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Yep, shaking the fermenter twice a day to rouse the yeast, without opening it, is the best way imho. But I would prefer not to do anything to opening and stirring (I've done both).
 
Toxxyc said:
Heh, we keep agreeing on the mead/wine stuff.

Degassing is not needed. Excess CO2 escapes and leaves the airlock. If you degas and take out some CO2 that'll just be put back by the yeast in a few minutes won't make any difference. I have made batches with and without degassing. I believe the ones without came out better, probably because I'm not opening the fermenter and forcing O2 into the mead two to three times a day.
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This sounds like an idea for a good experiment (for someone who has the time); make two side by side small batches, add staggered nutrients to both, but leave both closed and swirl/agitate one and leave the other alone except when adding the nutrient addition. The mead that was agitated often would probably finish fermenting first, but after a few weeks or a month would could you tell them apart by taste?
 
madscientist451 said:
This sounds like an idea for a good experiment (for someone who has the time); make two side by side small batches, add staggered nutrients to both, but leave both closed and swirl/agitate one and leave the other alone except when adding the nutrient addition. The mead that was agitated often would probably finish fermenting first, but after a few weeks or a month would could you tell them apart by taste?
Click to expand...
My guess is that if you are really trying to max out the alcohol tolerance of the yeast, you might actually end up with a difference. But I somehow doubt that this would be also true for a 12% abv Mead.
 
So now it could be two experiments, one being a high gravity mead, the other more "normal" strength.
I'm not home very much, so my mead gets two swirls a day, sometimes none, its never the same and I'm happy with the results when I use SNA, and even though I have no way of doing the above experiment, this thread has me wondering about it. Have we all accepted the "must de-gas" dogma when its not really necessary at the home brew level?
I definitely see an advantage of degassing at the pro level when primary fermenter space costs big money and there's desire to get mead on the market ASAP.
 
madscientist451 said:
So now it could be two experiments, one being a high gravity mead, the other more "normal" strength.
I'm not home very much, so my mead gets two swirls a day, sometimes none, its never the same and I'm happy with the results when I use SNA, and even though I have no way of doing the above experiment, this thread has me wondering about it. Have we all accepted the "must de-gas" dogma when its not really necessary at the home brew level?
I definitely see an advantage of degassing at the pro level when primary fermenter space costs big money and there's desire to get mead on the market ASAP.
Click to expand...
It's not degassing, it's rousing.

I got some nice vinegar touch in one of my meads that I continuously "degassed" by manual stirring in an opened bucket.... Won't do this again! After a few years it is drinkable now.
 
Mead makers actually do degassing, along with staggered nutrient additions. Co2 is poisonous to yeast in large amounts, and degassing helps in many ways. It helps bring in some 02, helps release trapped co2, etc. If you’ve ever vigorously stirred to break up the cap, you’ve seen a volcanic type of eruption of gas. Or, if you add your nutrients without dissolving them, you’ll get a Mentos/coke type of reaction where there is a ton of c02.

There are some peer reviewed studies on degassing and the health of fermentation in higher gravity musts. We can conjecture, but the studies have been really interesting and worth reading about.
 
So I have been rousing the wine once a day for a few seconds, just until all of the sludge is unstuck from the bottom. This is easily acquired since it is a smaller batch. What I have noticed is that the fizzy sound the wine makes will stop until an hour or so after it is roused, and will continue on basically all day. I would like to think this sound gives me an indication that the yeast are a lot more active and for that I thank you Miraculix. I feel a lot better about the turnout of this process due to these indications. You all are helping me with patience because once it stops making that lovely fizzy sound, for a beginner like me, IT'S TIME TO DRINK!
 
I ferment my primary in a bucket with plenty of extra room. For the first 4-5 days, I stir it twice a day until the bubbles being released slow down. That will degas and add some O2, which is needed in the early stages of fermentation. It's very easy to do if your primary is in a bucket. Once fermentation is mostly done, I let it settle for 24 hours and then rack into secondary That also releases some CO2. After that I let it bulk age.
 
Toxxyc said:
I've had a mead foam up and spray through the airlock when shaking the fermenter when closed. So now I just leave it to do it's thing. Same with my beers.
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HAHA concord grape wine can make quite a mess. I was cleaning purple spots for hours and my kitchen smelled like a brewery
 
Raptor99 said:
I ferment my primary in a bucket with plenty of extra room. For the first 4-5 days, I stir it twice a day until the bubbles being released slow down. That will degas and add some O2, which is needed in the early stages of fermentation. It's very easy to do if your primary is in a bucket. Once fermentation is mostly done, I let it settle for 24 hours and then rack into secondary That also releases some CO2. After that I let it bulk age.
Click to expand...
If you pitch enough yeast, there is no need for additional oxygen. Oxygen is needed for the yeast to quickly multiply. If the cell count is high enough, there is no need for additional oxygen. Oxygen can do a lot of damage.

If you then remove the majority of the yeast by racking into another vessel, you are actually making a problem even bigger.
 
madscientist451 said:
So now it could be two experiments, one being a high gravity mead, the other more "normal" strength.
I'm not home very much, so my mead gets two swirls a day, sometimes none, its never the same and I'm happy with the results when I use SNA, and even though I have no way of doing the above experiment, this thread has me wondering about it. Have we all accepted the "must de-gas" dogma when its not really necessary at the home brew level?
I definitely see an advantage of degassing at the pro level when primary fermenter space costs big money and there's desire to get mead on the market ASAP.
Click to expand...

That could be interesting, but if you're trying to push for ABV I'd rather recommend the step-feeding approach. I've made some REALLY strong meads pretty nicely using step-feeding, and it works. It takes time, but it works.

Yooper said:
Mead makers actually do degassing, along with staggered nutrient additions. Co2 is poisonous to yeast in large amounts, and degassing helps in many ways. It helps bring in some 02, helps release trapped co2, etc. If you’ve ever vigorously stirred to break up the cap, you’ve seen a volcanic type of eruption of gas. Or, if you add your nutrients without dissolving them, you’ll get a Mentos/coke type of reaction where there is a ton of c02.

There are some peer reviewed studies on degassing and the health of fermentation in higher gravity musts. We can conjecture, but the studies have been really interesting and worth reading about.
Click to expand...
I disagree, sorry. If CO2 was that poisonous to yeast, pressure fermentation would have presented A TON of issues. Yet it doesn't, and results in cleaner and faster fermentations. The studies I've read (and the real-world tests done by pretty famous mead makers like Ryan Carlson), shows that degassing makes no difference to the home brewer.
 
Toxxyc said:
That could be interesting, but if you're trying to push for ABV I'd rather recommend the step-feeding approach. I've made some REALLY strong meads pretty nicely using step-feeding, and it works. It takes time, but it works.


I disagree, sorry. If CO2 was that poisonous to yeast, pressure fermentation would have presented A TON of issues. Yet it doesn't, and results in cleaner and faster fermentations. The studies I've read (and the real-world tests done by pretty famous mead makers like Ryan Carlson), shows that degassing makes no difference to the home brewer.
Click to expand...
It should be also noted that the co2 levels in mead actually build up in minutes again, during active fermentation, so the degassing would need to be done like every ten minutes or maybe even continuously, to really show a significant effect on the average co2 level in solution.
 
I've listened to some, but its not one of my favorites. In your post (above) you mentioned "studies I've read", so I wanted to read them as well.
 
madscientist451 said:
I've listened to some, but its not one of my favorites. In your post (above) you mentioned "studies I've read", so I wanted to read them as well.
Click to expand...
I'll just post some links I can find offhand. Not all prove that it's not necessary, but rather points out the risk of introducing oxygen and why you should rather not bother on a homebrew level:

https://ilovewine.com/degassing-homemade-wine/http://www.techniquesinhomewinemaki...ent and Its Impact on Wine Chemistry v0.2.pdf
I should note that I'm not the type of guy who does something just because "that's how people have been doing it" forever. People have been advocating the degassing of wines for a while now, and just because they say it has to be done, doesn't mean it has to be (for me). So I've degassed and I've not degassed. My degassed meads are way less consistent to me.

EDIT: Oh yes, and I'm talking about degassing during fermentation here, not degassing prior to bottling. There's a difference, and an important one with a different end goal if you degas before bottling.
 
Toxxyc said:
EDIT: Oh yes, and I'm talking about degassing during fermentation here, not degassing prior to bottling. There's a difference, and an important one with a different end goal if you degas before bottling.
Click to expand...
Degassing in primary is useful prior to adding nutrients, to lessen the eruption effect of adding powder (nucleation). There's also a school of thought that gentle stirring to keep the yeast/lees in suspension has a positive effect on fermentation. I haven't done the with/without experiments to know for myself. But that's what the mead gurus are saying.
 
I bypass that nucleation by tapping off a little bit of the fermenting mead, heating it up in the microwave, dissolving the Fermaid-O into that hot mead and pouring it back into the fermenter. This does two things - I don't have to degas as it doesn't foam up, and it also sterilizes the Fermaid-O before pouring it in. Works for me.
 
Toxxyc said:
That could be interesting, but if you're trying to push for ABV I'd rather recommend the step-feeding approach. I've made some REALLY strong meads pretty nicely using step-feeding, and it works. It takes time, but it works.


I disagree, sorry. If CO2 was that poisonous to yeast, pressure fermentation would have presented A TON of issues. Yet it doesn't, and results in cleaner and faster fermentations. The studies I've read (and the real-world tests done by pretty famous mead makers like Ryan Carlson), shows that degassing makes no difference to the home brewer.
Click to expand...

Ah, but.....pressure fermentation DOES have those issues, but the key is a low pressure. Anyway, you don’t have to degas. I would recommend always breaking up the cap, to keep it from drying out (and getting moldy).
 
Neeb said:
So degrousing, (if that is even really a word) is degassing without oxygenation? Degassing involves mandatory oxygenation?
Click to expand...
As long as we are not arousing the yeast to much, it's all fine :D

If you open your fermenter, oxygen gets in. If not, it's not getting in.
 
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LOL arousing the yeast. I think that's a different discussion and might lead to a long and hard fermentation... :p

I'll finish off with one thought here (not saying I'm rage quitting at all, I enjoy the discussions), and that's that I believe A LOT of "rules" and stuff in the world of mead and winemaking is rested in tradition. Traditionally people used to:
1. Pitch perfect amounts of yeast, believing that overpitching is a very common problem.
2. Boil the crap out of their must prior to pitching the yeast, believing it's crucial to sterilize the must.
3. Add k-meta (Campden tablets) to the must prior to pitching the yeast.
4. Degas their meads and wines religiously.
5. Rack off the less VERY quickly, sometimes even in the middle of an active fermentation, because "autolysis is a problem".
6. Feed their yeast with DAP and all kinds of chemicals, usually all at once (at pitch), because they thought that's what yeast wants.

Today we know that lot of these rules and stuff are not only based in fiction (or doesn't benefit the homebrewer), but can even be harmful. We know, for example, that rehydrating yeast in DAP is bad. During rehydration the yeast cells cannot control what passes the cell membrane and the DAP then entering the cell is actually slightly toxic to the yeast. Therefore, rehydrate in water, if you rehydrate at all.

We also know that it's practically impossible to overpitch yeast with modern yeasts. Same goes for racking. The ONLY yeast strain I am careful with when it comes to letting the mead sit on the lees, is 71B, and even then it's a matter of months, not weeks like some believe.

I'm not saying I'm right, at all, trust me, because I'm usually not. I'm no expert, I'm no microbiologist and I'm no professional brewer/winemaker, nor to I proclaim to be.

What I am though is someone who's made it his life mission to make booze cheaply without sacrificing too much quality. I don't stick to guidelines and I do what I want. That includes making up my own recipes, and doing stuff I think will work only to learn if it does for myself. That includes the world of making meads. Yes, I haven't made a lot of mead in my life, maybe 200l or 300l or so, but the vast majority of that was made according to my own recipe, using my own logic and they turned out FANTASTIC. I didn't degas, I didn't use a drop of DAP, hell, I didn't even rehydrate the yeast (first batch, the rest was yeast collected from previous meads).

What I did do, and what I think is of utmost importance in making mead, was to stick to a very strict temperature control schedule. I made a must that wasn't too strong, I didn't aim too high and I didn't stress the yeast trying to hit super ABV numbers. I stuck to the TOSNA 2.0 schedule of feeding my yeast with organic yeast nutrients and I gave it time. I took 3 pages full of notes of the whole process the first time around, and compare notes of following recipes to it closely.

The result is meads I'm VERY proud of, even with minimal aging. One thing I haven't managed to get down yet is clear meads in a short time, but to me that's a small concern. My meads have always been VERY drinkable after 4~6 weeks and I'm really proud of that, considering I'm making mostly off-dry, semi-sweet traditionals, at 11% ABV with 71B (not the best combo).

So yeah, that's more or less my little story with this, and my reasoning for doing things a certain way. I learned A LOT from the guys over at GotMead and specifically spent some time on Ryan Carlson's podcasts. Lot of it is just banter, but sometimes VERY important info gets thrown out, I test it, and it works!
 
Toxxyc said:
LOL arousing the yeast. I think that's a different discussion and might lead to a long and hard fermentation... :p

I'll finish off with one thought here (not saying I'm rage quitting at all, I enjoy the discussions), and that's that I believe A LOT of "rules" and stuff in the world of mead and winemaking is rested in tradition. Traditionally people used to:
1. Pitch perfect amounts of yeast, believing that overpitching is a very common problem.
2. Boil the crap out of their must prior to pitching the yeast, believing it's crucial to sterilize the must.
3. Add k-meta (Campden tablets) to the must prior to pitching the yeast.
4. Degas their meads and wines religiously.
5. Rack off the less VERY quickly, sometimes even in the middle of an active fermentation, because "autolysis is a problem".
6. Feed their yeast with DAP and all kinds of chemicals, usually all at once (at pitch), because they thought that's what yeast wants.

Today we know that lot of these rules and stuff are not only based in fiction (or doesn't benefit the homebrewer), but can even be harmful. We know, for example, that rehydrating yeast in DAP is bad. During rehydration the yeast cells cannot control what passes the cell membrane and the DAP then entering the cell is actually slightly toxic to the yeast. Therefore, rehydrate in water, if you rehydrate at all.

We also know that it's practically impossible to overpitch yeast with modern yeasts. Same goes for racking. The ONLY yeast strain I am careful with when it comes to letting the mead sit on the lees, is 71B, and even then it's a matter of months, not weeks like some believe.

I'm not saying I'm right, at all, trust me, because I'm usually not. I'm no expert, I'm no microbiologist and I'm no professional brewer/winemaker, nor to I proclaim to be.

What I am though is someone who's made it his life mission to make booze cheaply without sacrificing too much quality. I don't stick to guidelines and I do what I want. That includes making up my own recipes, and doing stuff I think will work only to learn if it does for myself. That includes the world of making meads. Yes, I haven't made a lot of mead in my life, maybe 200l or 300l or so, but the vast majority of that was made according to my own recipe, using my own logic and they turned out FANTASTIC. I didn't degas, I didn't use a drop of DAP, hell, I didn't even rehydrate the yeast (first batch, the rest was yeast collected from previous meads).

What I did do, and what I think is of utmost importance in making mead, was to stick to a very strict temperature control schedule. I made a must that wasn't too strong, I didn't aim too high and I didn't stress the yeast trying to hit super ABV numbers. I stuck to the TOSNA 2.0 schedule of feeding my yeast with organic yeast nutrients and I gave it time. I took 3 pages full of notes of the whole process the first time around, and compare notes of following recipes to it closely.

The result is meads I'm VERY proud of, even with minimal aging. One thing I haven't managed to get down yet is clear meads in a short time, but to me that's a small concern. My meads have always been VERY drinkable after 4~6 weeks and I'm really proud of that, considering I'm making mostly off-dry, semi-sweet traditionals, at 11% ABV with 71B (not the best combo).

So yeah, that's more or less my little story with this, and my reasoning for doing things a certain way. I learned A LOT from the guys over at GotMead and specifically spent some time on Ryan Carlson's podcasts. Lot of it is just banter, but sometimes VERY important info gets thrown out, I test it, and it works!
Click to expand...
You can try adding NaCl to your water. I read that yeast flocks out much better if the Na level is at least at 50ppm in the water.
 
Miraculix said:
You can try adding NaCl to your water. I read that yeast flocks out much better if the Na level is at least at 50ppm in the water.
Click to expand...
I've done that, yes. It didn't work that well. What I have done is tried to fine using gelatin, but it's not very effective in meads. I'm now looking for more of a commercial wine clarifier, but it's a bit hard to get in South Africa where I am. We don't get all the cool stuff the guys elsewhere in the world take for granted.
 
Toxxyc said:
I've done that, yes. It didn't work that well. What I have done is tried to fine using gelatin, but it's not very effective in meads. I'm now looking for more of a commercial wine clarifier, but it's a bit hard to get in South Africa where I am. We don't get all the cool stuff the guys elsewhere in the world take for granted.
Click to expand...
Don't, it always takes away some flavor. Just wait it out or get a better flocking yeast.
 
Yeah I'm aware of the flavour/colour issue, but it's very tiny for me. I haven't used Gelatin in a while though as it just doesn't work. I need to find something like a 2-stage hot/cold clarifier that works well. Saw something like that in a handbook the other day, but again, finding it in SA is a PITA.
 
How many wines have you made and do you use Campden?
Thanks for your unprofessional opinion.
 

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