What does a secondary fermenter do?

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There are alot of ways folks can clarify their brews these days. From inline 1-micron kits that you can pick up for less than $40 shipped from many sources all the way to a secondary transfer and good ol' time and temp...with gelatin, isinglass and untold other options in between.

The malt the vast majority of us use these days has a higher percentage of fermentable sugars than barley from decades ago. Doesn't stop folks from doing decoctions tho (well it does stop most of us) ;)

The best takeaway is that the greater number of options on multiple fronts allows all of us to take our version of the hobby as far as we need to go.

In the past, with the material available at the time, a secondary was likely necessary to have a decently clear beer with a reasonable turnaround time, with notes added during maturation, however short. It's likely not necessary now. But "necessity" is always in the eye of the beholder when it comes to fermentation. :D
 
I also use a conical and no secondary. The advantage of course is that you can remove whatever you want (trub, yeast cake, any other small items that don't float) from the bottom, without introducing oxygen. I have the7 gal Fermzilla and love it. Another thing that I changed is that I do closed loop transfers to a keg, even when I intend to bottle. If bottles are in the plan, I add the priming sugar to the keg before purging O2, and then put 2-3 psi on it and cold crash. The liquid side goes to my bottling wand and the bottles are all pre-purged with CO2 after cleaning, covered with plastic wrap and a rubber band, and in a large plastic garbage bag that I use like a poor man's glove box. Needless to say, I only bottle a few - most of my beer stays in the keg :)
 
follow-up to ...
I'm actually kind of amazed that the kit-makers are still including a secondary in their instructions.
I scanned "top extract kit" instructions from a couple of online homebrew stores recently (early March 2021).

At least one store does not mention secondary in their online instructions (maybe they never did).

Another was "almost" secondary free - could it be that someone missed updating a PDF?
 
I also use a conical and no secondary. The advantage of course is that you can remove whatever you want (trub, yeast cake, any other small items that don't float) from the bottom, without introducing oxygen. I have the7 gal Fermzilla and love it. Another thing that I changed is that I do closed loop transfers to a keg, even when I intend to bottle. If bottles are in the plan, I add the priming sugar to the keg before purging O2, and then put 2-3 psi on it and cold crash. The liquid side goes to my bottling wand and the bottles are all pre-purged with CO2 after cleaning, covered with plastic wrap and a rubber band, and in a large plastic garbage bag that I use like a poor man's glove box. Needless to say, I only bottle a few - most of my beer stays in the keg :)

I want that exact Fermzilla. I have watched a bunch of videos on it an I'm convinced. I even like how if you use the collection jar to dry hop, you can purge the oxygen out of that with the side ports. That thing just seems super easy and convenient. I may not make the jump right away, but I think that is my next purchase. Glad to hear you like it
 
The not small problem with the Fermzilla is that little nasty writing which they put on it, and which says that you should not use it past 2 (or 3, I go by memory) years from production date, which is also written.

I don't think that it goes into pieces or it explodes after 2 years and 1 day from production, but the idea of buying something of that kind with an expiry date written on it is something that sends a shiver along my spine.
 
The not small problem with the Fermzilla is that little nasty writing which they put on it, and which says that you should not use it past 2 (or 3, I go by memory) years from production date, which is also written.

I don't think that it goes into pieces or it explodes after 2 years and 1 day from production, but the idea of buying something of that kind with an expiry date written on it is something that sends a shiver along my spine.

Really? Is that because it is plastic and not stainless? That would be a tough pill to swallow to spend $200 on one with all of the accessories and then have to replace it in 2 years.
I'm just using plastic buckets right now. Should i change those out after a while too? They are cheap enough to replace every year or two if need be.
 
Really? Is that because it is plastic and not stainless? That would be a tough pill to swallow to spend $200 on one with all of the accessories and then have to replace it in 2 years.
I'm just using plastic buckets right now. Should i change those out after a while too? They are cheap enough to replace every year or two if need be.

Yes, really.
I think this is because they should withstand pressure, and the producer doesn't want to have financial or other kind of trouble if the products begin failing serially. Recently they enlarged the opening which naturally makes the entire build less robust.

I think it's an ass-saving writing from their part. The fermenter is probably much more robust than that, but you know, if there is a problem, your problem. If you want to stay perfectly safe you can replace only the fermenter (not the accessories) but, again, those can be out of production in a few years.

If and when I get into this pressure thing, I think I will buy SS, it's more expensive but it's literally forever. I don't like replacing.
 
The Fermzilla manual says "If you use the fermenter under pressure hydro test the fermenter every 24months to ensure it is safe to use." <italics mine>
 
The Fermzilla manual says "If you use the fermenter under pressure hydro test the fermenter every 24months to ensure it is safe to use." <italics mine>

That would be certainly different. Somebody should tell us the exact writing on the fermenter. I saw a YouTube video where the writing was "not to be used beyond month/year with pressure applied" or something to that effect, if memory serves. That killed my interest in the product.

How can one make this hydro test?

Yes, it was "Test container or do not use under pressure" 8:39 then the person talks about replacing the stuff and that is what remained in my memory. It would be interesting to know how complicated is the test.
 
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Just reading reviews on a lot of these products, it seems like you get what you pay for. Buy plastic and receive plastic and realize that one day something is probably going to break.
 
Actually, going by memory which I see is defective 😲, I remember having read in some Italian forum of some people using the normal plastic fermenters with pressure, because any plastic fermenter can withstand some pressure. If 0,3 bar or less (5 PSI or less) is what is needed for pressure transfer it is entirely possible that one can pressure transfer from any fermenter, after applying the required holes and valves etc.

Carbonating is different because it requires 1 - 1,4 bar and requires something more specific.
 
Secondary vs not I - I haven’t observed a difference. I’m relatively new and can’t offer a scientific analysis. I am under the impression (possibly wrong - appreciate any input here) that oxidation is delayed/minimized when the CO2 from the final stages of fermentation are retained. If I ferment a beer and cap the carboy/conical at the end of fermentation (Spunding valve at say 5 psi or cap the carboy at the very end of fermentation) vs allow the CO2 to outgas through an airlock, the CO2 is retained and oxidation is minimized. The application would be to finish the ferment under pressure vs airlock. Let the beer settle under pressure vs airlock. Then if moved to secondary, the retained CO2 would minimize any oxidation risk. Thoughts?
 
Then if moved to secondary, the retained CO2 would minimize any oxidation risk. Thoughts?

Off-gassing CO2 would bounce a little bit of O2 away, but "minimize" would be wishful thinking. The way to minimize CO2 is to not do an open transfer.
 
I have a (modestly) contrarian opinion about secondaries; namely, I do a secondary to *reduce* oxygen exposure. Let me explain.

Like many(?), I learned to do primary fermentation in plastic buckets, secondary in glass carboys, and (originally bottle, but now) keg my beer. After a disastrous first attempt at a hazy IPA last summer (yes, major oxidation) I decided to get serious about doing semi-closed transfers between primary and secondary and between secondary and keg. After a number of less than successful combinations I have settled on the following process.
1. Do primary fermentation in my (otherwise now unused) bottling bucket. The lid seems to have a seal that is somewhat less tight than my fermentation buckets, but those don't have perfect seals either and the bottling bucket has a spigot.
2. After 5-7 days, do a full starsan/CO2 purge of a glass carboy, then do a pressure-assisted gravity transfer. Connect the hose just sanitized during the CO2 purge to the primary's spigot and connect the CO2 line to the airlock/blowoff hole in the primary, setting the regulator to ~2psi of CO2. The CO2 keeps O2 from filling the primary headspace and modestly accelerates the transfer (but will blow the top off the bucket if you turn the pressure too high!). Add dry hops, as needed (should be the only direct O2 exposure). Ferment in secondary 1-4 weeks.
3. (optionally) Cold crash in keezer, replacing the airlock with a mylar balloon filled with CO2 to reduce/eliminate O2 suck back.
4. When ready for kegging, do a full starsan/CO2 purge of a corny, then do a pressure-assisted gravity transfer from secondary under ~2psi of CO2.

This process requires a bit more equipment and futzing than an autosiphon, but introduces far less O2. And I am pretty sure that I reduce the O2 exposure of my beer compared to leaving it in primary, since the carboy is much less O2 permeable than the bottling bucket (or even a standard fermentation bucket). All of my IPAs, hazy or not, have much better hop flavors since I started doing semi-closed transfers.

The only real problem I have had with this process is independent of whether I use a secondary. Namely, when I do a closed transfer to the keg, if the beer has any dry hops (which many of my beers do) I occasionally clog up the liquid QD and have to stop/disassemble/clean/resanitize the QD and liquid post to clear the clog, which introduces some modest amount of O2 during the transfer.
 
@DavidWood2115

It seems that your reason to do a secondary transfer is that your secondary fermenter is in glass and therefore substantially exempt from air permeability, while your primary fermenter is in plastic and that is somehow less ideally gas-permeable for a 4-5 week fermentation.

If that's the case, I suggest you have a look at large-mouth glass demi-jones with plastic protections. They are in glass, they can be cleaned just like a plastic bucket, and you would avoid a transfer. And they have that nice plastic wrap which makes them so less dangerous than the naked glass carboys I see on sale in the US.

https://www.polsinelli.it/damigiana-34-l-bocca-larga-P536.htm
You can also find them with a tap

https://torricellibotti.it/dettagli...enti/damigiana-boccalarga-con-rubinetto-20-l/
 
Poor OP...just asked a question. This might have been said somewhere but instead of transferring to secondary, add the secondary hops to primary fermenter at day 3 of visible signs of fermentation. I used to secondary DIPAs but the flavor would only last 3 weeks because of the oxidation issue mentioned.
 
Yes, though technically I'm doing the tests to see if no-secondary improves my beer vs doing a secondary. If it doesn't, I'll probably go back to using the secondary because I'm used to the process. What I'm trying to find out is if the oxygen I introduce in doing a secondary makes any difference to me.

BTW: I think it's cute that someone thinks I could do a cold crash. My temperature control is my basement. One time during a very cold spell some years ago I did move the fermentation pail to the side of the basement with the furnace and hot water heater. Worked like a charm BTW.

It is cute that anyone on this forum would have the interest to try and share experiences and ideas with you to help you figure out your own best practices
brew on...
 
I'm sorry, @orionol73. I didn't mean it that way. I meant that I am no where advanced enough in my methods to do that type of thing. I meant it in a self depreciating manner, as a joke about me.
 
That's why I have to do the comparisons. I will post results, but the test brewing won't start until this summer.

So today I did a comparison of batch #278 and batch #279. This was my "Summer Ale" that uses amber dry malt extract, Centennial and Cascades hops, and US05 yeast. Batch #278 was brewed 4/25, transferred to a carboy secondary 5/1, and bottled 5/10. Batch #279 was brewed 5/2 and bottled 5/17.
At bottling, #278, left, was clear; #279, right, was lighter and cloudy:
at bottling.png

This is a combined picture when each was 3 week in the bottle, both clear and #279 is lighter:
at 3 weeks in bottle.png

Today, 6/7, they looked like this side by side.
in bottle 6:7.jpg

They pour clear and bright, and though #279 has slightly more sediment, it did not require any special handling.
in glass 6:7.png


So there was no difference in clarity, no real difference in sediment, and #278 was darker, a sign of oxidation. They tasted slightly different, with #279 having a sharper, more bitter taste and #278 being smoother. I and my fellow taster, who came up with the "smoother" descriptor, both preferred #278. Apparently we like a bit of oxidation.

In this comparison #278 was four weeks in the bottle and #279 was three weeks in the bottle. I will do at least one more comparison when batch #278 is at 6 weeks in the bottle. That's about the longest my ales last, but I might shoot for an 8 week test.
 
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I and my fellow taster, who came up with the "smoother" descriptor, both preferred #278. Apparently we like a bit of oxidation.

This is more common than people think (or admit). I'm convinced it's responsible for a lot of comments like "I do X <insert name of process that adds oxygen here> and it doesn't cause any problems. My beers are great!"
 
interesting comparison batches...but incomplete information...need details on fermentation equipment/process and bottling methods...

It's possible your methods caused agitation of trub in otherwise clear beer in the fermenter.

did you cold crash before bottling? How did you transfer? spigot or siphon? How did you bottle? mix sugar in a bucket or leave in fermenter undisturbed and added sugar to bottles?

The picture we need to see is the carboy pics right before bottling. Are they both equally clear? If so, then your methods disturbed the trub cake, and the fact that one carboy has more trub from no secondary is why that beer is more cloudy after disturbing the trub.
 
If I'm reading correctly, the Summer Ale recipe for #278/#279 is here: I brewed a favorite recipe today . Read the ingredients and process steps carefully - it's not the classic "lightest extract possible, add half at the start, ..." recipe.

For an amber DME base, the color of #279 seems "lighter than expected".

I'm also curious if there were any special techniques to get either of the beers that clear.
 
interesting comparison batches...but incomplete information...need details on fermentation equipment/process and bottling methods...

It's possible your methods caused agitation of trub in otherwise clear beer in the fermenter.

did you cold crash before bottling? How did you transfer? spigot or siphon? How did you bottle? mix sugar in a bucket or leave in fermenter undisturbed and added sugar to bottles?

The picture we need to see is the carboy pics right before bottling. Are they both equally clear? If so, then your methods disturbed the trub cake, and the fact that one carboy has more trub from no secondary is why that beer is more cloudy after disturbing the trub.
I will answer your questions, but please realize that my main points were that both beers were clear, both beers had little sediment, and one was darker.

1. Primary fermenter is a white plastic bucket.
2. Secondary is a glsss carboy.
3 I do not cold crash. I do not have temperature control beyond basement ambient temperature.
4. I transfer with a siphon. I start the siphon by inhaling on one end. When siphoning from the primary, I hold the intake end in the liquid, adjusting it as the level drops. I have been doing this for decades and am very good at it.
5. I bottle by transferring to a bottling bucket with the priming sugar.
6. I can't picture the two in carboys, because the one stays in the plastic primary and isn't visible. I can tell you that at transfer to the bottling bucket even the very top of the batch that was not subjected to a secondary was cloudy. It had nothing to do with disturbing the trub. The bucket wasn't even moved as it fermented on top of .a work bench. And, to reiterate, the cloudiness at bottling was not a problem in the final product.
 
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If I'm reading correctly, the Summer Ale recipe for #278/#279 is here: I brewed a favorite recipe today . Read the ingredients and process steps carefully - it's not the classic "lightest extract possible, add half at the start, ..." recipe.

For an amber DME base, the color of #279 seems "lighter than expected".

I'm also curious if there were any special techniques to get either of the beers that clear.

You are correct about where the recipe is posted.
#279 is lighter than I'm used to with this recipe, but, I am used to a secondary and not doing late addition of half my extract.

I don't do anything to clarify my beers. But the picture of those bottles is cellar temperature, about 68 F. And I am attaching a picture of the beers when first poured with a bit of chill haze. The bottles were in the refrigerator about 3 hours. I was aiming for 45-55, where I like my ales. The picture of the beer in glasses at the window was taken about 10 minutes after the pour and the chill haze is gone. So they aren't that clear if drunk at at an improper, uncivilized, taste-killing, ice cold lawn mower beer temperature.
poured 6:7.jpg
 
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This is more common than people think (or admit). I'm convinced it's responsible for a lot of comments like "I do X <insert name of process that adds oxygen here> and it doesn't cause any problems. My beers are great!"

Back at the end of 2018 I revamped my brewing process and stopped using a secondary (and other changes to reduce cold side oxidation). I was amazed at the impact to my Pale Ale batches, a style that I brewed a LOT over the years and I thought was the best style I made. With no change in recipe, my Pale Ales changed in appearance just like @D.B.Moody's examples. Much of the color and caramel-like flavors that I thought were from the Crystal malt was actually oxidation. I could definitely see the "sharper, more bitter taste...vs...smoother" comparison.
 
The not small problem with the Fermzilla is that little nasty writing which they put on it, and which says that you should not use it past 2 (or 3, I go by memory) years from production date, which is also written.

I don't think that it goes into pieces or it explodes after 2 years and 1 day from production, but the idea of buying something of that kind with an expiry date written on it is something that sends a shiver along my spine.
Most pressurised containers have expiry dates
 
If you transfer to a bottling bucket, you’re introducing the same chance of contamination and oxidation. If you filter, you are probably introducing more of both.
 
Over the past couple of years, both here and in other forums, people have been discussing processes that they use for bottling NEIPAs that stay fresh (for them) for 45 to 60 days.

The problems of excessive oxygen ingress are pretty well known. It will take a year or two for the solutions to become more well know.
 
Also I’d start using an auto siphon rather than doing it with your mouth. You could be introducing some fermentation bugs or bacteria there.
You are right by best practice, but I'm not that guy. I've been doing this for over 27 years now and have never had an infected batch. And I'm not trying to tell people what to do. I was just responding to a poster's questioning me about what I had done.
From my point of view my comparisons of secondary vs no secondary are about whether or not I care about the effect(s) of the oxygen introduced by doing a secondary, not what is best for most brewers.
 
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@DavidWood2115

It seems that your reason to do a secondary transfer is that your secondary fermenter is in glass and therefore substantially exempt from air permeability, while your primary fermenter is in plastic and that is somehow less ideally gas-permeable for a 4-5 week fermentation.

If that's the case, I suggest you have a look at large-mouth glass demi-jones with plastic protections.

What you say is good advice, but here's the thing:
1. The real reason I do a secondary is that it is how I learned to brew in 1994, and I am used to it.
2. 20 years ago, maybe 10 years ago, I would do that. Today I'm 78 and don't want more stuff. Frankly, I've only got a couple of years left to my brewing hobby.
3. Apparently, so far any least, I actually like the results of using a secondary. This may just be what I've come to expect and enjoy. It also may have something to do with me falling in love with English pub bitters on a trip to England, Scotland and Wales in 1988. I do not brew to produce ice cold lagers. I like cellar temperature ales. :mug:
 
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Just trying to figure out the difference in colors...

#278, the darker one on the left side, was subjected to a transfer to a secondary fermenter. #279, the lighter one on the right side, was not transferred to a secondary. The darkness of the one is a visible result of the oxygen exposure that such a transfer creates. #279 is a week younger than #278, but the second picture in post #61 pictures each when it was 3 weeks in the bottle (5 weeks from brewing) and #278 is darker.

Recipe at I brewed a favorite recipe today
 
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Although it's a day early, I did my 6 weeks comparison today. #278 (which was transferred to a secondary) is six weeks in the bottle and # 279 (no secondary transfer) is 5 weeks in the bottle.
#278 is darker than #279:
6:20:21.jpg


Both are clear and do not have sediment issues, so they easily pour clear:

6:20 pour.jpg



6:20:2021.jpg


They are both good. But my fellow taster and I now prefer #279, the batch that was not put into a secondary and is 5 weeks in the bottle. It has mellowed out from it earlier harsher taste and #278 seems to be past its prime. This is not much of a surprise as my beers rarely last 6 weeks after bottling. (Do the math: if you drink just two bottles a day for four weeks after the beer conditions for two weeks, you will drink 56 bottles, which is more than a 5 gallon batch produces. Since 1994, I have averaged only 10 brews a year.)
So, for me, using a secondary or not depends only on how long I intend to keep the beer. The next batches to compare are an IPA recipe, It will be interesting to see if that changes things. I'll report in July.
 
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[QUOTE="D.B.Moody, post: 9118608, member: 294452"
but I might shoot for an 8 week test.
[/QUOTE]

Well, we did a 8 week test today with #278 in the bottle 8 weeks and #279 in the bottle 7 weeks. #278 has been put through a secondary. We we surprised that our preference returned to #278 as being "smoother" than #279. Both beers are good, and I only notice the preference when this direct comparison is made. While this is confusing, the good news is that tasting of #280 and #281 begins Wednesday. Ya gotta love this hobby. :p

7/19/21 We drank the last two bottle today. #278 10 weeks in the bottle and # 279 9 weeks in the bottle. The preference was for #278, the one that was subjected to a secondary. We still liked both beers.
 
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