Crash Cooling Questions

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Kronos

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Having never done it before but in the process of building a fermenting fridge is crash cooling advisable for all your brews whether beer or lager.

Am I right in assuming you do this once fermenting is completed, at what temperature do you take it down to and for how long.
 
I dont think you want/need to crash Wheat beer as it's supposed to be cloudy. I think all other styles will benefit though - as for temp, as low as you can without freezing the beer (Although I did that once and it was still OK), I usually set my fridge to around 3.5 degrees.
 
crash chilling is an optional at the end of primary fermentation, if employed the cooler brew should drop out a bit more sediment a bit more rapidly, afaik the lower the temp the faster it can work, and even if used for a long time at a low temp you will still transfer enough live yeast invisible in suspension for a natural conditioning in the bottle or pressure barrel ok ;)

without bypassing the brewfridges internal thermostat you will be limited to circa 4C or the lowest temp the fridges thermostat will allow. If you bypass this then you can chill below 0C,

when employed i will give the fridge a day or 2 to drop to the crash chill target ( i generally set 0C as the target having bypassed my fridges thermostat)

and give it a day or 2 @ the low temp to settler out before kegging..

when kegging using pressure to condition, crash chilling has an extra benefit as cold beer is more accepting to conditioning via pressure
HOwever if naturally conditioning you will need to allow the brew to warm back upto fermentation temps before you can expect the residual yeast to revive from cold induced suspension and start the natural conditioning off.
For conditioning naturally you only need to ensure the brew is warm enough, you neednt get as precious about upper temps as you are with primary as the mass of the priming charge and its flavour contribution is nominal compared to the kilos of sugars consumed during primary ;)
 
I manage to get my fridge down to 1C without bypassing the thermostat. Might even go lower but I haven't tried.

As said you want to go as cold as possible without freezing, I think commercial breweries often go to -1. The length of time to then leave it, I heard, can apparently depend on the temperature. A day or 2 at -1 might be fine but at 4 degrees you might need to wait a week (made these figures up to illustrate the point, I'm not sure what the actual impact is). I normally do 3-4 days at 1 degree.

If you want to go all in for clarity you can also add gelatin once the beer had chilled. This should really help to drop everything out and get your beer clear in record quick time. I did this for the first time with a mild I bottled recently. Just tried one after two weeks in the bottle and it's crystal clear (despite being dark) and tastes much cleaner than I'd normally expect after such a short time plus less sediment in the bottle. I also cold crashed a hefeweizen I just bottled, even though they're meant to be cloudy. It should still be cloudy due to the protein in the wheat and once carbonated should still be plenty of sediment to swirl up for that hefe character!

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So once cold crashed for 2 or 4 days at 1c what temperature is it best to bring the wort back up to before bottling or barelling can be done.
 
bottle and barrel when cool, and let the bottles and barrel warm back upto rermentation temps, Idealy the same temp as you fermented the brew at.

If using a priming charge calculator that uses the beer temp remember to use the temp prior to crash chilling, its used to evaluate the level of disolved co2 in the brew and crash chilling will not add co2 just increase the beers capacity to absorb it when under pressure.
 
bottle and barrel when cool, and let the bottles and barrel warm back upto rermentation temps, Idealy the same temp as you fermented the brew at.

If using a priming charge calculator that uses the beer temp remember to use the temp prior to crash chilling, its used to evaluate the level of disolved co2 in the brew and crash chilling will not add co2 just increase the beers capacity to absorb it when under pressure.
I am not sure what a priming charge calculator is Fil, I'm relatively new to all this, I just need to know at what temp I add the sugar and can bottle or barrel.
 
IF crash chilling bottle/barrel and add the sugar when cool then ;)
- Though its not a hard and fast rule and you can warm the brew back up in advance if you like..

My reason behind suggesting to bottle/ barrel cool is while cooler the sediment that has dropped out may be more inclined to remain as sediment as you rack/drain off, where if warmer the sediment may be more prone to disturbance? this is after all the feature of chilling the brew your trying to exploit ;)


Just be aware that Beer bottled cold will soon warm up to yeast friendly fermentation temps to condition your brew, beer in a pressure barrel will take longer to warm up due to its larger thermal mass.

So simply monitor you beer after packaged, and when its warm (18c+? check lowest temp suggested for fermentation on your kit?) start your 2-3weeks conditioning period ;)

You DONT want to bottle/barrel, warm up, Then add sugar.. That would be a VERY BAD IDEA, post fermentation you want to limit the beers risk of contact with 02 as much as possible so bottle/barrel AND prime in the single hit ;)




if you google 'priming charge calculator' you will find a few offerings hosted by brew communities all over the world and they are intended to help you calculate a precise priming charge to condition your beers to a specific target of co2 concentration.
Some are simple others more involved - go check em out but dont feel obliged to use them.

tbh i have never used one and simply add a level teaspoon(3g) of white sugar to each 450-550ml('pint') bottle.

But if after a precise condition target for your brew then the highest temp the brew sat at fermenting will dictate the maximum level of co2 that is contained already in the brew. It dissolved as it bubbled up during fermentation.

This indicates the additional condition required by adding the priming charge. If a crash chil temp is used it will suggest the brew contains a lot more co2 than it does as little or no extra co2 will get absorbed while its chilling as the yeast have finished creating it even though the colder brew has a much higher capacity for co2 absorption.
 
ps i only know its 3g of sugar i use as i weighed a teaspoon of sugar after buying some £5 drug dealer scales for hops after years n years of brewing..

the only things with brewing you NEED TO GET RIGHT are the basic cleaning sanitation, and if bleach based sanitiser is used THREE TIMES RINSING preparation. Respect for your ingredients, Keeping the brew at a yeast friendly temp, and Once fermentation is underway avoiding contact with O2 ;) beyond that its an open field.
 
I dont agree with "crash" chilling at any stage of homebrewing.
1, Why, what are the benefits?
Yeast is a living organism. its comfortable in its own temp range.
2, it wont make your beer any clearer. Only time and gravity will do this.
3, It prevents "chill haze". No it wont... the suspended proteins are still there in your beer. Homebrewers cannot remove suspended protiens.
4, Ferment at 20oC (whatever). Bottle/Keg at 20.oC for 2 weeks.
5, Let time and gravity drop the yeast out of suspension.
 
Thank you for that detailed reply Fil.

So this is what I was thinking about doing once the fermentation is finished in the FV.

1. Drop the temp of the wort in the FV to 1c for say 3 days.
2. Then Bottle or barrel the beer and add the sugar while still a 1c.
3. Then just let the barrel or bottles get to room temp on there own.
4. Or bring the temp back up to 18c in the fermenting fridge.
 
Thank you for that detailed reply Fil.

So this is what I was thinking about doing once the fermentation is finished in the FV.

1. Drop the temp of the wort in the FV to 1c for say 3 days.
2. Then Bottle or barrel the beer and add the sugar while still a 1c.
3. Then just let the barrel or bottles get to room temp on there own.
4. Or bring the temp back up to 18c in the fermenting fridge.

sounds like a solid plan to me :drunk:
 
I agree with johnnyboy1965. Besides, yeast is as important to flavour as the hops & malt. Use Irish Moss in the brew, time will clear the rest.
 
I have a fridge in which I crash cool at the end of the primary to help drop the yeast, but although the beer is nearly clear after two or three days in the fridge, there is still enough yeast left to carbonate the beer, it might just take a little longer.
However I don't bother with temperature correction for primary sugar addition on the cold beer, since I take the view there is no need in my case. My reasoning is that if you allow the primary to completely finish (for me usually after about 16 days) then cool it, the CO2 in solution stays there, no more CO2 is added in the cooling and cold states, so when the beer is warmed up again you have exactly the same amount of CO2 present as when you started out (other than that derived from priming sugar). In fact if I did temperature correction for priming I would end up with beer that is overcarbonated relative to where I wanted to be.
 
I agree with johnnyboy1965. Besides, yeast is as important to flavour as the hops & malt. Use Irish Moss in the brew, time will clear the rest.

Me too. Really can't be bothered with all the faffing about - the ale clears to star-bright in pretty short order anyway, and I'm not so impatient that a few more days would hurt.
 
As good a thread as any to ask this.... when I put my bottled conditioned beers in the fridge, why do they go cloudy after some hours? They remain cloudy even if I leave them there some days. I have never crash cooled a fermenter, but in my small example practice, it seems to have exactly the opposite of the intended effect. And I guess it is yeast haze, and not chill haze, because it doesn't happen with bottles without yeast.

My best guess it that the rapid chill effect has created eddies that move the yeast around the bottle. If I could hold off drinking for more than a few days, they might clear (but I never managed to conduct that experiment).

Can anyone enlighten me?
 
As good a thread as any to ask this.... when I put my bottled conditioned beers in the fridge, why do they go cloudy after some hours? They remain cloudy even if I leave them there some days. I have never crash cooled a fermenter, but in my small example practice, it seems to have exactly the opposite of the intended effect. And I guess it is yeast haze, and not chill haze, because it doesn't happen with bottles without yeast.

My best guess it that the rapid chill effect has created eddies that move the yeast around the bottle. If I could hold off drinking for more than a few days, they might clear (but I never managed to conduct that experiment).

Can anyone enlighten me?
I think what you are describing is protein haze, which forms on cooling, and is not affected by gravity forces ie the proteins don't settle with time. It's not yeast that is magically returned to suspension.
My understanding is that the more you move towards using grain rather than simple malt extract for brewing the more likely you are to get a haze.
If you allowed your bottles to warm up the haze should disappear.
 
I crash cool all my brews, except for stouts, the reason I do it is for clarity, it also really helps when you have done a big dry hop, the hops drop out nicely when it gets cold. I have brewed the same AG recipes with and without crash cooling and there is a noticeable difference in clarity on the crash cooled brews, I also like the reduction in bottle sediment crash cooling creates. I crash at -1 now, usually for about 2 days. Be careful of advice you get that is not backed up by anything more than a brash opinion...
 
I crash cool all my brews, except for stouts, the reason I do it is for clarity, it also really helps when you have done a big dry hop, the hops drop out nicely when it gets cold. I have brewed the same AG recipes with and without crash cooling and there is a noticeable difference in clarity on the crash cooled brews, I also like the reduction in bottle sediment crash cooling creates. I crash at -1 now, usually for about 2 days. Be careful of advice you get that is not backed up by anything more than a brash opinion...
Do you bottle and prime while the wort is still cold or do you bring the temp back up first.
 
I always thought you could crash cool in the bottle. Maybe I will try it in the FV after fermentation next time. I have just done my first proper AG attempt and when I bottled it looked as clear as mud.
 
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