Forced Cooling vs Natural Cooling

[Rick_UK]

Hi Gents

Just wondered what the pros and cons are on this. My last brew (AG3) I cooled naturally overnight, the previous 2 I sat in a bath of cold water (the wort not me!) and cooled over a period of a few hours. I have just bottled AG3 a few days ago and it still seems very cloudy compared to the previous 2 which were about 70% clear after this period of time. Could this be due to the fact that it cooled over a longer period after the boil.

I'm considering investing in a wort chiller/cooler but only if it going to add value so to speak.

Thanks

Rick

[Kev888]

Hi,

I asked about this sort of thing and also did a bit of research on it some time ago, and the general opinion seemed to be that it didn't make much difference (to the beer) to cool the wort quickly, it was really just convenient (and something to boast about ). The only issue I came up with was needing to protect the wort from infection whilst it cooled, particularly as nasties could get a head start over the yeast.

That said, I also came across threads where people were concerned about the wort sitting on the trub for too long, but no-one had any particular justification for this that I could find at the time, so I never really got to the bottom of that one.

I think covering up the boiler and waiting is quite common, IIRC in Australia.

Cheers
kev

[EoinMag]

Hi,

I asked about this sort of thing and also did a bit of research on it some time ago, and the general opinion seemed to be that it didn't make much difference (to the beer) to cool the wort quickly, it was really just convenient (and something to boast about ). The only issue I came up with was needing to protect the wort from infection whilst it cooled, particularly as nasties could get a head start over the yeast.

That said, I also came across threads where people were concerned about the wort sitting on the trub for too long, but no-one had any particular justification for this that I could find at the time, so I never really got to the bottom of that one.

I think covering up the boiler and waiting is quite common, IIRC in Australia.

Cheers
kev

The Australians, due to water restrictions tend towards a method that they call no-chill, where they fill the wort, whilst still scalding hot, into a cube, or Jerry can. The lid is then put on and that is allowed to stand for as long as they want, it can be months at a time.

The main reason that they don't want the break material in there too long is that it leads to higher hop utilisation than if you get off all of the break and gunk material, but it appears it's no biggie and with a bit of practise you can get it just right.

The settling of the break material is a function of temperature and not a function of how fast you reach that temperature and as you point out you really just want to get to pitching temps as soon as you can to avoid infection, but as is the way with these small details, it becomes blown out of proportion and is a race situation. The risk of infection is pretty minimal at this stage, so I'd personally not worry much.
If you cap it while it's hot and sterile then it will remain that way until you break the seal again.

[Rick_UK]

Thanks for the replies chaps. So I take it clarity wont be improved with forced cooling.

As i brew of an evening and leave it to cool overnight there doesn't seem to be much point in getting a wort chiller, so more money to spend on hops and grain!

[Wolfy]

Thanks for the replies chaps. So I take it clarity wont be improved with forced cooling.

As i brew of an evening and leave it to cool overnight there doesn't seem to be much point in getting a wort chiller, so more money to spend on hops and grain!

Not sure I agree with that, but I'll let the experts explain better than I can: http://www.howtobrew.com/section1/chapter7-4.html

[boingy]

Being of the old skool, I've always considered the cold break to be a really important part of the gig. However, on the few occasions when I have cooled overnight (through laziness or equipment problems) I have seen no real difference in the end result. This is not a very scientific observation. Most of my beer gets drunk fairly young so long term stability and going off are not really an issue. And I do battle the haze with some of my brews regardless of the cooling method. Nevertheless I rather suspect that the cooling is not quite as critical as some writers make out.

Having said that, there is one really good reason to cool quickly. Wort is at its most vulnerable between boiling and pitching so minimising this time is probably a good idea. I've never been happy wasting all that cooling water so now I use the garden pond as the heat sink (watertight connections are essential if you try this!).

If you are going to skip any of the "normal" stages in home brewing I reckon cooling is the one to go for. That's not to say that you should skip it, just that it is one of the less important stages imho.

[Dr. Dextrin]

Thanks for the replies chaps. So I take it clarity wont be improved with forced cooling.

As i brew of an evening and leave it to cool overnight there doesn't seem to be much point in getting a wort chiller, so more money to spend on hops and grain!

Not sure I agree with that, but I'll let the experts explain better than I can: http://www.howtobrew.com/section1/chapter7-4.html

Interesting link that Wolfy. It definitely says that you need to cool *quickly* or all the cold break won't be precipitated. It also definitely says that failure to cool quickly is what causes chill haze.

However, when I raised this issue a while back on JBK, Graham Wheeler said that the idea that rapid cooling precipitated more cold break than slower cooling was probably a myth. Also, I think we all know that even rapid cooling doesn't prevent chill haze in the finished beer. To get rid of that, you need to fine/filter the beer or mature it at low temperature to let the haze drop out.

So my feeling is that even experts can talk rubbish. Applying that in an unbiased way to all experts, I'm still unsure myself whether rapid cooling has any real benefits (assuming you avoid infection, which I've never found to be a problem). So generally speaking I don't bother and just let the wort cool overnight. I've never noticed any difference myself.

[EoinMag]

Thanks for the replies chaps. So I take it clarity wont be improved with forced cooling.

As i brew of an evening and leave it to cool overnight there doesn't seem to be much point in getting a wort chiller, so more money to spend on hops and grain!

Not sure I agree with that, but I'll let the experts explain better than I can: http://www.howtobrew.com/section1/chapter7-4.html

Interesting link that Wolfy. It definitely says that you need to cool *quickly* or all the cold break won't be precipitated. It also definitely says that failure to cool quickly is what causes chill haze.

However, when I raised this issue a while back on JBK, Graham Wheeler said that the idea that rapid cooling precipitated more cold break than slower cooling was probably a myth. Also, I think we all know that even rapid cooling doesn't prevent chill haze in the finished beer. To get rid of that, you need to fine/filter the beer or mature it at low temperature to let the haze drop out.

So my feeling is that even experts can talk rubbish. Applying that in an unbiased way to all experts, I'm still unsure myself whether rapid cooling has any real benefits (assuming you avoid infection, which I've never found to be a problem). So generally speaking I don't bother and just let the wort cool overnight. I've never noticed any difference myself.

If you want a practical discussion of this in any meaningful way then you'd get a better crack at it on the likes of the aussiehomebrewer website, I'm sure this has been gone through there ad nauseum as there are a lot of people who practise it. It's arguable anyway that chill haze is only an issue for lagers and lighter summer drinks, an English Ale should never be cellared at temps that would cause chill haze.

[boingy]

So my feeling is that even experts can talk rubbish.

That is maybe putting it a bit strong but there is certainly plenty of areas of disagreement between the movers and shakers in the home brew world. On this forum we tend to be fairly GW-centric, probably because he actively participates, but that doesn't mean that he is automatically right about everything and that other authors are automatically wrong (soz Graham!). There are definite regional trends, where UK, US and Aus brewers differ and I think there is also still quite a lot about the science of brewing that is not fully understood, even by the boffins with big foreheads.

We are very fortunate that we can still brew decent beer without worrying too much about some of the finer details.
If you are happy with your processes, stick with them. If not, then change something.

[Kev888]

We are very fortunate that we can still brew decent beer without worrying too much about some of the finer details.
If you are happy with your processes, stick with them. If not, then change something.

I must admit I'm tending more and more to this view myself - I do want to learn and understand as much as possible of course, as that way lies improvement and progression, but ultimately if my beer is good with whatever methods then the details are perhaps for secondary satisfaction.

I'd like to think though that whilst the experts undoubtedly disagree (about a lot!) that its generally on things which are fairly subtle or only very meaningful on much larger and/or commercial scales and different situations; should something have a wide and demonstrable effect then i'd like to think 'mostly' there would be more acceptance of it. Maybe..

Cheers
kev

[Bribie]

I have used the so called "no chill" method, using a plastic cube, since I started doing full mash brewing two and a half years ago. I did a "cold break" experiment - splitting a brew into top and bottom halves and fermenting separately - that showed, on that occasion anyway, that CB has little or no effect on the flavour or clarity of the beer.

However the main problem with no chilling in a cube is that the wort stays at above 80° for a fair while, so any flavour or aroma hops may continue to isomerise, and there is a perception that aroma can be "nuked" in the cube as well.

Personally I haven't found excess bitterness to be a problem, but recently I've been using a method - suggested by a fellow Oz brewer - to avoid late hop additions being nuked. The idea is to simply do a bittering addition during the boil. Cube the resulting wort. The next day, chill it down to around 8°.Then pour around 3L into a stockpot and do the 10 minute or flameout hop addition right there. Pour the hot wort (or strain if using flowers) straight into the FV. Pour the cold wort in as well from the cube. This gets to about pitching temperature so pitch immediately.

I've found this to markedly increase hop aroma in beers that use late hopping. There are calculators online for mixing hot/cold liquids so this is quite controllable and not seat of the pants at all.

[Rick_UK]

Great discussion gents and obviously a contentious issue!

I like the approach of just finding out what works best with your set up and sticking with it if you are getting good beer.

Bribie - Interesting idea about the aroma hops, sounds similar to the concept of 'hop tea' popular with homebrewers many years back (and probably still used by many). Would there not be an issue with hop utilisation when only boiling in 3l of wort? I'm keen to try this with my next batch if it works though.

Rick

[crookedeyeboy]

Forced cooling precipitates out alot of protein from both hot break AND cold break therefore you will end up with a haze at some point in the beers life due to it still being in solution, IE if you put a beer in the fridge to cool before drinking it the chill haze will be alot worse than if the beer had been crash cooled. Its not just to speed things up it does alot more than that.

[EoinMag]

Forced cooling precipitates out alot of protein from both hot break AND cold break therefore you will end up with a haze at some point in the beers life due to it still being in solution, IE if you put a beer in the fridge to cool before drinking it the chill haze will be alot worse than if the beer had been crash cooled. Its not just to speed things up it does alot more than that.

I don't get why the speed of precipitation should make any difference. Surely if stuff drops out at a particular temperature and is insoluble at that temperature then it does not matter how fast you get there? Why should the speed make a difference. Do you have any scientific backing for why this should be the case, apart from quoting how to brew or something where it's stated, but it wouldn't be the first thing that Palmer got wrong either.

[InsideEdge]

Well I suppose it is my aim to produce beers of the quality we can buy here in the UK and all/most of the uk micro's will cool their wort as quick as they can. So that's is what I seek to do.

AND I wouldnt get to use my big shiny coil otherwise!