Cold crashing

[smitty8202]

I hear a lot of people talking about cold crashing their brews. What is it and what are the advantages of doing it?

 

[RandallFlag]

In brief, it's cooling your beer to 40 deg F or below before you bottle to encourage the remaining particles to fall out. Chilling helps this process, especially dry hopped remnants.

 

[smitty8202]

So is it beer type specific or any type will work. So I basically put my Carboy in the fridge then bottle?

 

[McKnuckle]

Any type will work, but it's not usually appropriate to do for naturally cloudy beers such as various wheats. It's not rocket science... it just takes advantage of the natural tendency of suspended particulate matter to settle in cold liquid. One minor bit of advice would be to cold crash the carboy in a location from which you don't need to move it when you package. That way you minimize any agitation of the settled junk on the bottom.

 

[normonster]

Cold crash 2 days then let temp rise back to seller temp then keg/bottle.

Really helps with clarity.

 

[andrewmaixner]

Cold crash 2 days then let temp rise back to seller temp then keg/bottle.

Really helps with clarity.

Why do you let temps rise back up before kegging/bottling?

 

[Owly055]

Any type will work, but it's not usually appropriate to do for naturally cloudy beers such as various wheats. It's not rocket science... it just takes advantage of the natural tendency of suspended particulate matter to settle in cold liquid. One minor bit of advice would be to cold crash the carboy in a location from which you don't need to move it when you package. That way you minimize any agitation of the settled junk on the bottom.

I sometimes do brews with a significant percentage of wheat...... but not "wheat beers". I cold crash everything I brew. One brew with 75% wheat comes out crystal clear..... and I like it that way... It isn't a Hefe. I'm not a Hefe fan at all, and this bears on comparison to a Hefe. But then I'm not fanatical about adhering to a specific "type"..... A Hefe is expected to be cloudy...but it's not a requisite characteristic of a wheat beer........ I like my beer clear.

H.W.

 

[McKnuckle]

It's all good, man. But if you were brewing a hefe or a traditional Belgian wit and trying to adhere to style, cold crashing for clarity would not be advised. I was just trying to answer the man's question without leaving gaps.

 

[normonster]

Why do you let temps rise back up before kegging/bottling?

I don't remember but it's a common practice and there is some explanation out there.

You should buy Palmers "How to Brew"....lots of answers in there...online first edition is free too...Google that up and you can learn a whole bunch.

 

[Clonefan94]

Makes a big difference on clarity. I make sure to always do it when I dry-hop especially. Really drops everything out of the beer making for a non-clogged autosiphon during transfer to keg.

 

[Westermans]

I was told by a local brewery owner never to cold crash if you are bottling. You drop all the yeast out needed to carbonate. Any truth to this?

 

[hannibalmdq]

I was told by a local brewery owner never to cold crash if you are bottling. You drop all the yeast out needed to carbonate. Any truth to this?

In a word, no. It'll drop a lot of the yeast out of suspension but there are plenty left to do the job of bottle carbing. It may take another week to carb up verses your normal timeline but it will happen.

 

[andrewmaixner]

I don't remember but it's a common practice and there is some explanation out there.

You should buy Palmers "How to Brew"....lots of answers in there...online first edition is free too...Google that up and you can learn a whole bunch.

I have the current edition, and have read the whole thing, but I don't recall this info. I'll have to go do a search for it.

 

[andrewmaixner]

I have the current edition, and have read the whole thing, but I don't recall this info. I'll have to go do a search for it.

Did a search of the current edition, but no information on this was forthcoming. The closest thing was the paragraph on priming lagers: http://www.howtobrew.com/section1/chapter11-7.html which references that you may need to add some yeast back into super-clear lagers before bottling, and to culture/add the yeast at the same temperature to avoid thermal shock.

 

[Teromous]

Take a look at this chapter from How to Brew.

 

[normonster]

Did a search of the current edition, but no information on this was forthcoming. The closest thing was the paragraph on priming lagers: http://www.howtobrew.com/section1/chapter11-7.html which references that you may need to add some yeast back into super-clear lagers before bottling, and to culture/add the yeast at the same temperature to avoid thermal shock.

Hmmm. Maybe I got it from the book Yeast. It has something to with yeast cleaning up some of their own byproducts or something. The real reason I do it is because I have the capability with my fermentation setup so it's easy. Whatever it was I read was backed up by another article I found where they interviewed a brewery (10 barrel maybe) and they said that is what they do.

Same reason I do 115-130 minute boils....there is science behind it but I just do it because it's a common commercial practice and if possible I like to make commercial quality beer.

Some people really like to know why things work but I'm happy without knowing as long as it improves quality or at least my own perception of it.

 

[normonster]

I'll add that since I've been cold crashing and then raising temp back up, doing longer boils and scooping out hot break, and precisely controlling mash temps and fermentation temps, my beer has been very good. My next intended step is to get a good grip on pitching rates and then water profiles.

 

[andrewmaixner]

Hmmm. Maybe I got it from the book Yeast. It has something to with yeast cleaning up some of their own byproducts or something...

Definitely true, though I believe that the 'cleanup' phase would generally be completed before you cold-crash. I've been told by one of the experts here that the "yeast cleanup" phase is fairly fast, and that much of the improvement from a 1-2 month conditioning happens regardless of yeast being present.

 

[normonster]

Interesting. I guess the true reason I do it is because I read it on the Internet....lol.

 

[MindenMan]

Getting beer crystal clear before going into the keg makes a lot of sense. Anything in that keg is going to age as long as there is beer in there. If there is no sediment in the beer as it goes into the serving keg, it is very likely to taste exactly the same from the first pull to the last pull. As far as "cleanup" phase goes, commonly referred to as a D-Rest, after your beer is done fermenting, slowly raise it up to 70*F over the course of a few days to eliminate diatcetyl if present. Then cold crash below 40*F for 4 or 5 days to settle out, and then rack into keg or bottling bucket. I am confused about cold crashing and then raising the temperature back up, why would you raise the temperature back up? I must have missed something in your previous statement... I cold crash fermenter, rack into bottling bucket leaving the nicely compacted trub cake behind, prime accordingly, and bottle. I too want as clear as is possible beers, that will age well for their style. I strain my wort between the BK and the fermenter, to add as little as possible trub to my fermenter, and consequently keeping my yeast cake/trub as small as possible to eliminate a major waste during racking.

 

[gwaugh]

One thing to consider, if you are concerned about oxidation, is cold crashing in a keg. The decrease in temps in a fermenter will draw oxygen in. I normally rack to a Co2 purged keg, crash in the keezer overnight, then fine with gelatin. Yes the first pint or two need to be discarded but it's not a big deal to me.

 

[hannibalmdq]

One thing to consider, if you are concerned about oxidation, is cold crashing in a keg. The decrease in temps in a fermenter will draw oxygen in. I normally rack to a Co2 purged keg, crash in the keezer overnight, then fine with gelatin. Yes the first pint or two need to be discarded but it's not a big deal to me.

Also, if you're a bottler and you ferment in PET, you can just put an un-drilled universal stopper on and let the sides of the fermenter suck in as it reabsorbs the CO in the head space. Not recommended for glass carboys.

 

[GHBWNY]

I am confused about cold crashing and then raising the temperature back up, why would you raise the temperature back up?

Relative temp at priming is not as critical as being sure to properly calculate amount of priming sugar to add for that temp. The vol's C02 you want for the style you have made is determined by temp of beer at priming along with total gal. amount of the batch. If you're not careful to prime for temp, it may over-carb and possibly create bottle-bombs. I use Northern Brewer Priming Calculator.

I'm guessing that having priming temp closer to conditioning temp, say, 65F and 70F respectively, versus 40F and 70F, would be easier on the yeast and might result in a more predictable carbing.

 

[GHBWNY]

I cold crash my primary for 24 hrs. in fridge (except wheat). Then add gelatin and leave in fridge another 3 days. Pull out of fridge and set fermenter where bottling will take place so it warms back up undisturbed. Super-clear beer every time!

 

[MindenMan]

I appreciate the priming calculators, but I don't sweat it; I generally add 0.75 oz of priming sugar per gallon for porters, stouts, and ESB's. For other beers I will add 1 oz per gallon, as lighter styles can use a little extra mouth feel.

 

[normonster]

...I am confused about cold crashing and then raising the temperature back up, why would you raise the temperature back up? I must have missed something in your previous statement....

You said it...it was the d-rest I was after. So maybe I'm wrong to crash and then d-rest. I'm already fermenting at 68 with s05 though so moving up to 70 isn't much.

Do you think my method of cold rash then ramp back up for D-rest is BS? I've been getting great results but maybe that sequence is unnecessary.

 

[normonster]

I also looked everywhere for what I thought I'd read about that sequence and can't find squat so maybe I made that up....lol that I put it on the Internet....can believe everything on here I guess....lol

 

[gwaugh]

If you're going to do a d-rest then you should do it before you do any kind of crash. Ferment at what ever temp you want for the batch until it is mostly done, then ramp up a few degrees for a d-rest. The first few days is when the yeast could produce undesirable phenols and such if the temps are out of control. After fermentation is most the rise in temp for the d-rest will merely keep the yeast active and let them clean things up a bit.

 

[smitty8202]

Bringing this back to life. So I have a cream ale in my primary that has been in there since the 31 jan. I ordered a keg kit yesterday. Hopefully it should be here by next Friday/Saturday. Is it safe to go ahead and put the carboy in my fridge which is at about 35 till then or is that too long in there?

 

[schokie]

It'll be fine. In fact, it'll be better.

Check that fermentation is complete of course, but for a cream ale you can safely assume it's done by now.