Three times in two weeks I've had to witness a crime: libel, or the publishing of false information that is damaging to one's character. The victim? Your yeast. A substantial number of anti-yeasters out there are trash-talking your yeast. They think they're weak. They think they're lazy. They think that they aren't up to the job of carbonating your beer. And these yeast-haters are nearly always wrong.
This week we'll be talking about bottle conditioning. Why it's (probably) good, how to do it to get the beer you want, and most importantly (as someone who hates to see kindly single-cell organisms run down unjustly) how little you really need to worry about the ability of your initially-pitched yeast to do the job.
In Defense of Bottling
I know that many of you hate bottling, and it would seem to fly in the face of the entire Beer: Simple philosophy (one keg is simpler than 60 bottles). But sometimes you need a bottle of beer (competitions, to share at the homebrew club meeting, bring to a dinner party, etc.). In that situation, knowing how to bottle condition effectively is useful (and let's not forget that bottling off of your kegs comes with its own challenges and variability, so it isn't as simple as "bam, ONE transfer into the keg!" unless you NEVER take/send beer anywhere). Even when kegging, I bottle-condition a gallon of the beer and set it aside for evaluation and sharing.
It's also worth knowing about because if you're a prolific brewer (which you should be - at least once a month, and preferably twice!) you're going to run out of kegs sooner or later and have to resort to bottles.
And not for nothing, but I've never had all of my bottles go flat all at once right before a party (thanks, bled-off CO2 cylinder...my kegs are now paperweights...).
So now and again, you'll need to bottle. And there's anecdotal evidence that it has some benefits in terms of flavor: the additional mini-fermentation may take up the oxygen in your head space (if there was any) and provide one last chance to clean up fermentation byproducts. I've looked for scientific research on this, but wasn't able to find any - as a side note, does anyone else think it's time for the AHA or some such body to produce a peer-reviewed journal about homebrewing? I do.
But in any case, I've done it both ways (-phrasing-) and my limited sample shows that my bottled-off-the-tap beers score lower and have a shorter stable shelf-life than my bottle conditioned beers. For what it's worth.
Bottle Conditioning Basics
Nothing complicated here. I mean, it's more complicated than, "well, guess I'd better pitch all five ounces of this here bag marked 'primin' sugar' into the beer!" (yes, that was written in a "yokel-ly" voice; sorry), but it's not much more complicated than that.
You don't want to "rule of thumb" this. Why not? Because there's no reason to. There are any number of perfectly reliable nomographs and calculators out there to give you the amount of carbonation you actually want. So it by calculation. So here's a simple process:
- Determine your beer volume. It'll be a little less than what's in the fermenter: you'll lose some in transfer.
- Determine the beer's temperature. The colder it is, the more CO2 is already in suspension. You don't need to rectal-thermometer this thing, but within a few degrees, work out what temp it is at bottling.
- Determine your desired CO2 level. When in doubt, 2.25 is a good "go-to," but many beers have a traditional level that you might consider following - or go your own way! But like every other part of your recipe, it should be a choice, not an accident. Think of CO2 as an ingredient.
- Decide on a source of priming sugar. Corn sugar is most-common. Cane sugar is fine. You can also use DME, LME, honey, molasses, brown sugar, maple syrup - hell, almost anything with simple sugars in it. But be aware that it might impart a touch of flavor, especially if we're talking a cooked sugar. Regular table sugar is perfectly fine.
- Punch this info into a calculator. I use this one because it was the first one I saw when I Googled "priming sugar calculator" years ago. There are lots of others. They're all pretty damned accurate.
- Weigh your sugar, mix it with a cup or two of water, dissolve it, and boil for a minute or so before adding it to the bucket. Then rack your beer on top of it. No need to stir - the natural motion caused by the liquid transfer should more than adequately mix it in, and stirring can add oxygen that you don't want in the beer.
And that's it. Consistent bottle conditioning. If you DON'T get carbonation the answer is almost certainly this simple one: keep them warm. I almost always see near-complete carbonation in a week or 10 days. If I don't, it's winter - and so I've learned to simply put them in the warmest room in our house (Laundry Room, if anyone cares) or stack the cases on top of the air register in the brewery and cover them with a towel or blanket so they get a nice shot of warm air at regular intervals. But the answer has never, not once, been an inability of the yeast to properly carbonate the beer.
(Don't Fear) the Reaper
Now, on to the thing that prompted me to write this in the first place.
Your yeast aren't dead. Much like [SPOILER ALERT!] a certain Game of Thrones character, they're still very much alive.
This might be one of those times when the brewing purists, dogmatists, and scientists will leap onto their keyboards to exclaim about how I must be wrong. This is definitely, though, also one of those times when my answer is, "OK, but I've done it this way for years, and either I'm a pathological liar or maybe there's more than is dreamt of in your philosophy."
Don't worry about adding extra yeast. Your existing yeast can do the job.
"But it's been in the fermenter for four weeks!" Don't care.
"But the ABV is 8.1%!" Don't care.
"But it got cold and the yeast are definitely dormant!!!" Don't care.
"But I racked to secondary!" Don't care.
"But I filtered all the yeast out!" Don't c- actually, yes, if you did that, then add more yeast.
But the rest of it? Seriously - don't sweat it. There are still lots of yeast there, and they can do the job.
"How do you know, alehole ?" [Trademark pending, btw...] Because I've bottle conditioned with no additional yeast for....literally every beer I've ever put into a bottle, and every time I think the yeast won't handle it because of some terrible thing I've done to them, I'm proven wrong by those hardy little bastards.
Secondary? The yeast are still there. If you haven't filtered them out, they're still present. Moving the beer off of the yeast cake shouldn't matter at all.
Length of time? I recently brewed a braggot with Adam Crockett of Haymaker Meadery (congrats to Haymaker on their recent Mead Free or Die medal!!!). We made it for a beer festival in December, so this was October. Unfortunately it didn't make it to the festival (I ran out of kegs, and he has two real jobs, so...), and I forgot about it in the hustle and bustle of the holidays. Then I started a busy, busy semester and was on a brewing hiatus (hence, I didn't visit my fermentation fridge), and it just sat. And sat. And sat. For FIVE MONTHS. And guess what? Bottle conditioned to 2.5 volumes with no additional yeast.
ABV? Don't make me laugh. My biggest "normal" beer is an 11.2% Wee Heavy. No problems at all. Bottle conditions right up.
Cold treatment? Please. I once over-froze an Eisbock that was already at 9% alcohol and three months in the carboy, and freeze-distilled to just over 13% when I iced-off about 40% of it by accident. Carbed up just fine - it took a little longer (three weeks instead of 10 days), but no problems.
I've never yet had the yeast fail me. And as you can see, I've tried.
Now, is there a chance that my abused and stressed-out yeast are carbonating my beer but also adding off-flavors to it? I guess it's possible. But if so, they aren't adding much - it's a very small fermentation, and I've not noticed any "stressed-yeast" off-flavors, nor have the judges who have evaluated it. In fact, my best-scoring beers historically are the very-lowest ABV (3.0% Berliner Weisse) and one that's fairly-high (8.5% Dopplebock). There's no significant correlation between ABV and scoring or flavor stability in my data.
The bottom line here is that by adding a new yeast pitch, you're adding a step. You're adding cost. You may be adding variability in your process if you don't do it consistently. You might be adding a wild or mutated yeast, or contamination. And you'd be doing it for basically no reason.
If you're having issues with getting your beer to condition, check the thermostat. It's been the culprit in every "missing carbonation" case I've ever worked.
So condition away, and trust in your yeast. They are wise, and they will take care of your beer.
Keep it simple.