Why I do secondary fermentation

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What I intended to say was a sealed chamber with an airlock, in a situation where the wort beneath is still emitting CO2, or to the point where it is no longer emitting but has no O2 ingress.

The problem is that once the CO2 "wind" stops, that airlock becomes a two-way street, with CO2 diffusing out and O2 diffusing in. Don't get me wrong...the fact that the O2 has to work it's way through a bit of vodka or starsan or whatever is better than a dry opening, but it's not the same as a sealed vessel. At that point, the CO2 barely matters (except for any random collisions that happen to bounce O2 molecules temporarily away from the beer, which delays the inevitable, but only for a little while).
 
I started regular brewing with wine. We used secondaries and even third-iaries to clear. Never heard any concern over air exposure during the short periods when the product got transferred or bottled.
A few notes here:
Beer is not wine and can't be treated the same way.
Wine is not brewed, it's "made." ;)
Wine is sulphited each time before manual degassing and racking. The sulphite binds the O2.
Wine can oxidize too.
 
The problem is that once the CO2 "wind" stops, that airlock becomes a two-way street, with CO2 diffusing out and O2 diffusing in.

This only happens if there's a change in wort or ambient temperature, correct? Or are you saying that O2 will diffuse through the water in the airlock, and then into the vessel?
 
Insert Educational Video <HERE>

The point of that video is basically, "use the correct bell and fill to the correct level, and you'll reduce the chances of sucking fluid into the fermenter." But that doesn't have anything to do with dissolution and subsequent diffusion of O2.
 
Insert Educational Video <HERE>


In the first few seconds and about 2 minutes in he touches on exactly what I said: a change in temperature creating suck back and introducing O2. If you have means of controlling temp, this can be mitigated.

I can see how some O2 might diffuse into the airlock solution, but I have a hard time believing there is enough external pressure in a temp controlled environment to allow for meaningful O2 diffusion. If someone has some an explanation sans suckback due to temperatures changes, I'd be interested in giving it a read.
 
I can see how some O2 might diffuse into the airlock solution, but I have a hard time believing there is enough external pressure in a temp controlled environment to allow for meaningful O2 diffusion.

You're looking for an overall air "pressure" as the cause, but it's not needed. All you need is Henry's Law, followed by Fick's Law.
 
That video is incorrect though. The material and the liquid are still permeable. Measurement of Oxygen Transfer Rates for Carboy Closures and Air Locks | Semantic Scholar

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It is also important to realize that gasses mix per there partial pressures, not the complete gas pressure. A fermenter at 10psi pure CO2 with a silicone gasket (very permissible) it going to have O2 ingress over the gasket even though the internal pressure is higher because O2 partial pressure in the ferementer is lower than atmospheric.
 
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That video is incorrect though. The material and the liquid are still permeable. Measurement of Oxygen Transfer Rates for Carboy Closures and Air Locks | Semantic Scholar

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It is also important to realize that gasses mix per there partial pressures, not the complete gas pressure. A fermenter at 10psi pure CO2 with a silicone gasket (very permissible) it going to have O2 ingress over the gasket even though the internal pressure is higher because O2 partial pressure in the ferementer is lower than atmospheric.

Exactly what I was hoping someone could respond with. Very helpful, thanks!
 
I also am not sure I would know if any of my beer has been completely ruined by O2. They must all be and I just refuse to admit it.
Most of my beer barely ages long enough to carb properly (LOL). So I guess I'm just saying is, "to each their own". I like the beer I end up with
Now back to your normally scheduled thread,,,
Cheers, :mug:
Joel B.
I Enjoyed your rant. :D I did mine on "Transfer from primary to secondary" thread in the Beginners beer Brewing Forum.
 
"taking brewing too seriously has a tendency to lessen the fun factor." This.

I don't secondary because I'm lazy.

I have 2 14 gallon plastic fermenters. There is about 1.5" of space under my bottling valve, the beer is clear enough without racking to a secondary. On the other hand, now that I have a valve in my fermenter (why didn't I do that years ago?) it would be really easy to rack to a secondary with minimal splashing.
 
my "secondaries" are 2 litre bottles. Easy to compare them with 750 ml secondaries. Ferment 5 - 6 days, bottle via jug and funnel. The bottling releases CO2 so the bottle is flushed out prior to capping. works for me.
 
I secondary every beer I brew. I prefer to think of it as a settling tank. As OP states, sediment always falls out. And no, that doesn’t automatically mean anyone sucks (pun intended) at syphoning and pulls junk. It means there is still suspended particluate that falls out. It’s also good to use to cold crash beers that you want to, and its the place to add gelatin to the beers you want to. People made and still can make good beer without obsessing over every molecule of O2 in the world’s atmosphere. I can only note that we’re also living in an era where people think hazy and cloudy beer is normal and some even think its a good thing
 
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This was mentioned earlier in the topic ...

Some beer styles, a little o2 exporsure will not make a huge impact.

Some it’s even desirable (aged barleywines)

... but oxygen 100% degrades beer, especially hop dominate beers.

Oxygen ingress is immediate. The impact may be noticeable. In addition to closed transfers, there may be ways to minimize the impact. Recently, there have been some interesting topics that focus on "how can we reduce the impact and get good results". For example, successfully bottling NEIPAs.
 
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For example, successfully bottling NEIPAs.
Can you provide a link to this thread? I’m interested to see the process. Also interested to see if there are any closed transfer keg brewers who have done this process and then a blind triangular test to possibly identify the differences
 
I am also one of the converted. Used to do secondary all the time. One time, due to circumstances beyond my control, a English Bitter set on the Trub in the Primary for 45 days vs the Primary/Secondary. It was clear and Delicious, Delicious Beer. There are lots of procedures and myths about Brewing. We used to go to extremes not to introduce O2 into the Wort. This was apparent when we returned our SG Sample to the Brew Pot (generally before Boil). Now we all shout Out "Don't Aerate the Wort" in good fun while some one returns the sample. I do know there is a whole idea of low oxygen brewing.

My Beer shelf life is very low. It must be drank within a month of Brewing!

BTW, some Stouts can be aged for a year or more with very pleasing results. I try to save some Stout to age, but it normally does not happen.
 
Yes (for the most part).

What matters more is what you'll do with the beer after the 3 months. If the 3 months is nothing more than aging time to condition the beer, you can do it in the serving package (bottles or keg) and keep it safe, ready for consumption when the time comes. That's why a secondary is unnecessary - the package essentially serves the same purpose.
So, if I do this for this Stout, the priming sugar won't have an affect on the way it is suppose to condition? My first Stout, so I really don't know much about it.
 
Can you provide a link to this thread? I’m interested to see the process. Also interested to see if there are any closed transfer keg brewers who have done this process and then a blind triangular test to possibly identify the differences
I'll check my notes - IIRC, there are a number of threads both here and over in /r/homebrewing.

I would anticipate that people discussing ideas in these threads would be open to constructive ideas.

I doubt that anyone in those topics is ready to claim that these processes are ready for the blind triangle testing you mentioned.
 
I don't think there is anything particularly special about stout in this regard. A tiny amount of re-fermentation in the bottle is a brief event, lasting just a few days. It takes longer to be perceived as fully carbonated, so don't get those two related but different things confused.

After carbonating, and indeed during that time as well, the beer will just sit and condition as it would in bulk in a secondary vessel. Of course there may be subtle differences that no one can possibly predict, and which in my opinion don't matter at all.

If you age something for months in secondary, keep in mind that you will then also have the very real chance of difficulty carbonating in the bottle due to drastically lower yeast viability. You would probably want to re-yeast the beer to ensure success, creating another variable for you to manage. So I would not go that route personally.

If you have a vessel you can use for secondary that holds some of the beer, try an A/B test yourself. Condition a portion in secondary, and bottle condition the rest. Then come back and give us your impressions. :)
 
If you age something for months in secondary, keep in mind that you will then also have the very real chance of difficulty carbonating in the bottle due to drastically lower yeast viability. You would probably want to re-yeast the beer to ensure success, creating another variable for you to manage.

Good point. The only beers I age for months would be big beers, like barelywine. I have one now that I just put in a secondary on top of a few ounces of oak chips that were soaked in bourbon for about a month. I’m thinking that one will sit for at least 3 months, maybe more.

Or I would let mead sit, especially if its high gravity. I like those aged on oak too.

With these beers, I generally have not added fresh yeast at bottling, but that’s not a bad idea - especially with bigger beers. I think you just don’t want to use a champagne yeast at bottling. Although it has a high alcohol tolerance I found it usually changes the beer too much and the times I’ve tried it I’ve not liked the end result.

I generally ferment my big beers with something like a 1028, a 1728, or a well built up 1056. These are beers I usually brew to have for the winter and over the holidays. Beers I never open right away or am never anxious to get at in a week or two, so they may sit for several weeks at least after bottling before I even open the first one. Those yeasts usually seem to have enough left to finish the job. They tell you to be sure to pick up a small amount of the yeast off the bottom into the bottling bucket.
 
Good point. The only beers I age for months would be big beers, like barelywine. I have one now that I just put in a secondary on top of a few ounces of oak chips that were soaked in bourbon for about a month
This is not the thread really for me to give advise on this but the bourbon you soaked the chips in will have the most flavor of oak. You would have been far better off just adding that bourbon to your barleywine at packaging. You would of accomplished the same thing and saved yourself a lot of time of aging and o2 exposure.
 
I use a secondary on occasion and have heard heard of all the "dangers" also. I'll have to do a search and see how many batches were ruined due to transferring from one vessel to another. I usually don't use a secondary unless I need to free up my primary or adding ingredients later in the process. I also enjoy all the steps involved in brewing and like to fidget, even if means using a secondary.

Sure, things can always go wrong during any step of home brewing but then again automobile accident happen every day too.....
 
I use a secondary on occasion and have heard heard of all the "dangers" also. I'll have to do a search and see how many batches were ruined due to transferring from one vessel to another. I usually don't use a secondary unless I need to free up my primary or adding ingredients later in the process. I also enjoy all the steps involved in brewing and like to fidget, even if means using a secondary.

Sure, things can always go wrong during any step of home brewing but then again automobile accident happen every day too.....
I think the problem here is people think it has be “ruined” for this to be true. It doesn’t necessarily have to be that extreme. But it will drop the quality of your beer compared to if you did not use the secondary
 
Can you provide a link to this thread? I’m interested to see the process. Also interested to see if there are any closed transfer keg brewers who have done this process and then a blind triangular test to possibly identify the differences
(11) Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA | HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.

(11) NEIPA Bottle Oxidation and alternatives? | HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.
 
Now I think I’m going to try this with a few bottles before I keg. Then I can do a blind triangle test with my club and see if they can detect a difference. Not doubting that you can bottle a NEIPA and have it not oxidize to hell but I would believe there will be drop in aroma and flavor vs. closed transferring to a fully purged keg.
 
Not doubting that you can bottle a NEIPA and have it not oxidize to hell but I would believe there will be drop in aroma and flavor vs. closed transferring to a fully purged keg.

I agree with this. I think a lot of people look at oxidation as binary, which of course it's not. Every beer has some. It's just a question of how much and how soon it affects the beer's flavor and aroma perceptibly.
 
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I would believe there will be drop in aroma and flavor vs. closed transferring to a fully purged keg
That's already been noted by the OP in reply #278 of Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA.

The OP has been active in the thread for 2.5 years.

If you decide to do an evaluation and decide to share the results, PLEASE BE KIND.

Like I said earlier, I doubt that anyone in those topics is ready to claim that these processes are ready for blind triangle tests (bottling vs closed transfer kegging).
 
That's already been noted by the OP in reply #278 of Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA.

The OP has been active in the thread for 2.5 years.

If you decide to do an evaluation and decide to share the results, PLEASE BE KIND.

Like I said earlier, I doubt that anyone in those topics is ready to claim that these processes are ready for blind triangle tests (bottling vs closed transfer kegging).
I looked at that post #278 and also from what I’ve seen from @Taket_al_Tauro , he only bottling his ipa and doesn’t keg, so his post would only show the findings of the best bottling techniques, not a comparison(if I am incorrect here please correct me). My goal would be to see you if there is a detectable difference from doing the best possible reduction of DO levels bottling vs. kegging with the triangle test using the same batch of beer. I’d simply report my finding and let you decide. That way people who continue to brew hoppy styles can determine if the $200+ investment in kegging is worth it (for me it’s worth it in time, pbw, and starsan alone)
 
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I didn't know my beer sucked in 2007 until I tasted my beer in 2009 and then I didn't know that beer sucked until I tasted my beer in 2014 and on and on. Everyone thinks their homebrew is amazing and perfectly executed but it's a lot of proud papa goggles. If you don't accept for a minute that you might be able to improve by doing research, experimenting and sometimes listening to others who have done those experiments, your beer will only be as good as it is right now. There are plenty of people who are perfectly Okay with that. We, collectively, probably need to let those people continue being happy with their "possibly" less than amazing beer.
 
I’d simply report my finding and let you decide.

Personally, I suspect it's one to two years too soon to start benchmarking these proposed / experimental bottling processes. And I'd rather be a year late with the benchmark(s) than a year early.

But if the various OPs are willing, in advance, to get some feedback, that could be interesting as well.
 
Personally, I suspect it's one to two years too soon to start benchmarking these proposed / experimental bottling processes. And I'd rather be a year late with the benchmark(s) than a year early.

But if the various OPs are willing, in advance, to get some feedback, that could be interesting as well.
I’m confused how it’s an early thing. Earth was always round...even when it was thought to be flat. If you get what I’m saying
 
I started regular brewing with wine. We used secondaries and even third-iaries to clear. Never heard any concern over air exposure during the short periods when the product got transferred or bottled. Never had a problem with the results as long as you had the patience to let things age. Equipment was rudimentary compared to what is available now. Buckets, carboys, airlocks, siphon, bottles. Maybe a press if you got fancy. The things you could accomplish with that kit were always interesting and sometimes even astonishing.
The variation in quality of home made wine is on the same playing field as beer. The main difference is that sophisticated wine makers use additions of metabisulfite at various stages of the process to mitigate the oxygen damage. That, combined with the fact that wine benefits from small amounts of oxidation in its flavor maturation, makes it tolerate oxygen from careless transfers. Without sulfites, storing wine in buckets and racking with racking canes will definitely show age quickly (poorly) in the bottles.

As far as beer quality goes, I can't tell the difference. If you blind taste-tested me between the two methods I couldn't distinguish.
...
I agree that it's standard knowledge air exposure is not a good thing after fermentation has started and that limiting it to the extent possible is best practice. I have also seen some great setups to eliminate all exposure that are tempting to try. But IMO, taking brewing too seriously has a tendency to lessen the fun factor. I'm good with electric all-grain and limit exposure as possible. Don't think I will ever get tired of that or need to rent a storage unit for my gear.
I disagree that if you don't avoid air exposure at all cost, you're a brewtard and have compromised beer.

Brewtard is a little harsh. "compromised" is a subjective term. Maybe you have a hard time picking out the flavor characteristics of oxidation. All beer currently on earth is in the process of spoiling. The idea behind all the careful process and gadgets is to move the timeline so that the drinker's threshold to perceive of spoilage is moved past the day they consume it. It doesn't have to make the process less fun and it certainly doesn't have to take up more space. Just get a fermenter that can have CO2 hooked to it. Purge out the kegs before filling. It's small things like that that make a huge difference.
 
I didn't know my beer sucked in 2007 until I tasted my beer in 2009 and then I didn't know that beer sucked until I tasted my beer in 2014 and on and on. Everyone thinks their homebrew is amazing and perfectly executed but it's a lot of proud papa goggles.

I usually get some pushback when I say this, but the worst person to evaluate the quality of a beer is the person who brewed it. Cellar blindness is not just a wine thing.

I once ran an (anonymous) survey of homebrewers. Of those that felt they had enough information to form an opinion, 69% believed their homebrew was better than average. 25% believed their homebrew was about average. 6% believed their homebrew was below average.
 
I realize there are a number of fellow homerbrewers whom put down, pooh-poh, criticize, act if I’m a complete reta*d and diminish doing a secondary. Well… I always do a secondary and I’m da*n glad. For a minimal amount of work I’ve been able to “leave behind” the goop shown in the photos.

BTW, I’ve never introduced an infection or oxygen, by doing a simple transfer from primary to secondary regardless to the claims of the pooh-pohers.

Also, a secondary gives me the opportunity to cold condition 5.25 gallons at a time and to fine said 5.25 gallons whereas, I would not be able to do with the primary 11.5 gallons.

Goop left behind in the secondary avoiding transferring over to bottling or kegging.
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Hmm... what beer do I end up serving?

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Do what works for you. Over the thousands of years that humans have been brewing, we have tried many things that work for some and not others and we still have not perfected that one procedure that works for everyone. What I have learned, in this particular group, is that if "some" people disagree with you they will insult you, belittle you, challenge your intelligence and be mean. There are an equal amount of people wanting to help you so, take ever response with a grain of salt.
 
OK, I can assure every one, that most of my beers meet the most important judge,,, ME. I am not making beer for any body else. I have no pretense (or daddy goggles as was so eloquently said) that it is the best and could not taste better. But I also have a budget to my beer making. $200 here, $100 there, to me, is $300 that I could spend on ingredients, not hardware to make my crappy beer a little bit better. I seldom if ever see anyone use a scale on how much better their beer is after they spend $$$ on the latest and greatest hardware. Did your beer go from "3" to "5",,"7" to "9" or better yet "2" to "8" when you spent $300?
Some of you are in the hobby to make world class beer and have the means to do it. Some of us just make (now I question) drinkable beer. I guess I'd rather have 30+ gal of "my quality" beer than 5 gal of "perfect" for the same investment.
I hope I don't come off sounding like I don't appreciate all the experimenting and research that some of you do and your helpful comments, quite the opposite really, I would probably enjoy some of your "failures" as much as I do my meager results.
Cheers, :mug:
Joel B.
 
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