Wort Chilling Speed

[Jakechan]

I know, Im showing my geekiness but I was intrigued by all that talk the other day regarding wort chilling, and the need to use agitators to speed up the process.

Well I made the effort today while cooling my wort with my crappy home made chiller, to log the temps every minute throughout. It took 39 minutes to chill from 87 down to a steady 32.4, at which I called it quits and whacked it in the fridge. (I had a 20 minute steep after flameout hence it had already dropped a bit).

The result is displayed by this simple graph. The blue control line is the temp of the tap water running through the chiller at 30.2



This is all just out of interest, you can make of it what you will.

Cheers,
Jake

 

[braufrau]

Oooh I love a good graph! So there's no point in chilling longer than 30mins!

 

[Jakechan]

Oooh I love a good graph! So there's no point in chilling longer than 30mins!

Well, probably not with my system anyway. But other people here may have different experiences of course.

Cheers,
Jake

 

[Peter Wadey]

I know, Im showing my geekiness but I was intrigued by all that talk the other day regarding wort chilling, and the need to use agitators to speed up the process.

Well I made the effort today while cooling my wort with my crappy home made chiller, to log the temps every minute throughout. It took 39 minutes to chill from 87 down to a steady 32.4, at which I called it quits and whacked it in the fridge. (I had a 20 minute steep after flameout hence it had already dropped a bit).

.....
Cheers,
Jake

Jake,
An Agitator?
Agitation can be as simple as moving the coils around in the pot - something to get some crossflow happening.
Whirlpooling with a spoon or recirculating wort by pump are other methods.

Just to be sure, can I take it that you did nothing to move the wort wrt the coils?

If not, then I would like to see you repeat the experiment, but this time keep the coils moving.
Then replot the graph.

To complete the picture you really need to give some idea of your experimental setup - eg wort volume chilled, chiller dimensional information, flow rate, ambient temp, lid on/ off etc.

PW
PS Have a pot cloth handy

 

[Offline]

Another thing that would be of interest with your graph would be the temperature of your cooling water (Tap water?)

Im guessing 28-30 degrees

 

[haysie]

Another thing that would be of interest with your graph would be the temperature of your cooling water (Tap water?)

Im guessing 28-30 degrees

The blue control line is the temp of the tap water running through the chiller at 30.2

 

[Jakechan]

Jake,
An Agitator?
Agitation can be as simple as moving the coils around in the pot - something to get some crossflow happening.
Whirlpooling with a spoon or recirculating wort by pump are other methods.

Just to be sure, can I take it that you did nothing to move the wort wrt the coils?

If not, then I would like to see you repeat the experiment, but this time keep the coils moving.
Then replot the graph.

To complete the picture you really need to give some idea of your experimental setup - eg wort volume chilled, chiller dimensional information, flow rate, ambient temp, lid on/ off etc.

PW
PS Have a pot cloth handy

Gday Peter,
Its not really an experiment, just me observing the cooling rate of my wort. Nor is it an "experimental" setup, its just how I make beer.

The chiller was not moved during the cooling process.
Kettle = 50 litres
Wort = 34 litres
Chiller dimensions? See pic (half inch copper pipe)
Flow rate? Bloody good
Ambulance temperature = 30
Lid off (pretty hard to dip the thermometer otherwise )



Cheers,
Jake

 

[Peter Wadey]

Gday Peter,
Its not really an experiment, just me observing the cooling rate of my wort. Nor is it an "experimental" setup, its just how I make beer.

Cheers,
Jake

Jake,
Then you sought to learn nothing from this? Rubbish!
Come on, make something of it. Don't let it be a waste!
Despite it not being ideal, there is still the potential to learn something from it.
Looking forward to the follow up plot for the next 34litres.
Just don't leave it till winter .......and don't burn your hands on the coils.

Rgds,
Peter

 

[Jakechan]

Damn you scientist type guy...now I will have to do it all again next week while shaking my coil

 

[Jakechan]

Actually Peter, my impetus for posting this graph was to try and engage some discussion regarding chilling with a coil and the apparent desperate need to agitate while chilling. My graph was presented as a means of proving that perhaps there is no need to agitate, as I find the results already more than acceptable.

Granted, a comparison done next week while agitating will provide more evidence one way or another. And yes....I will give it a go

Cheers,
Jake

 

[Darren]

Moving the chiller will work ALOT better.

cheers

Darren

 

[Jakechan]

Moving the chiller will work ALOT better.

cheers

Darren

Aha....that remains to be seen!

 

[SJW]

Moving the chiller will work ALOT better.

cheers

Darren

Yes it certainly does. Stick a temp probe in and see for yourself.

Steve

 

[Jakechan]

Wort Chilling Part 2

Ok, did a brew today and had another go at this.

This time I agitated the wort constantly by shaking the immersion chiller coil throughout the entire chilling process. Fortunately this was a lot quicker than the last time, which already points to a result.



There were however a few different details.

The chiller was constantly moved during the cooling process.
Kettle = 50 litres
Wort = 36 litres
Chiller dimensions? See pic (half inch copper pipe)
Flow rate? Bloody good
Ambulance temperature = 29
Lid off (pretty hard to dip the thermometer otherwise )
Control temp of cooling water was a bit cooler this time at 27.5.
Initial temp was higher this time, as I started cooling at flameout rather than wait for 20 minutes.


Cheers,
Jake

 

[jeddog]

This time I agitated the wort constantly by shaking the immersion chiller coil throughout the entire chilling process.

Just a quick one , a little off topic....how do ya whirlpool while chilling with an immersion chiller

 

[technocat]

Just a quick one , a little off topic....how do ya whirlpool while chilling with an immersion chiller

With great difficulty, thats why I opted for a counter flow chiller

 

[Steve]

Damn you scientist type guy...now I will have to do it all again next week while shaking my coil

just get a clean, long steal spoon from the kitchen and stir it the opposite way to which the water is flowing inside.

 

[dr K]

Great wort or was that work Jakechan.
Now it clearly indicates what we know from common sense, and that is that if the wort is agitated then cooling will be quicker.
It shows though that the real time saving is very small, say eight miunutes difference between rest to 5C> tap cooling water. I could be argued that the additional speed of cooling creates more cold break, but if that break is being agiatated along with the wort will that in turn reduce the total cold break?
Either way the fermentor ends up with lot more trub and spent hop residue that really cannot be good for your beer.

K

 

[haysie]

Great wort or was that work Jakechan.
Now it clearly indicates what we know from common sense, and that is that if the wort is agitated then cooling will be quicker.
It shows though that the real time saving is very small, say eight miunutes difference between rest to 5C> tap cooling water. I could be argued that the additional speed of cooling creates more cold break, but if that break is being agiatated along with the wort will that in turn reduce the total cold break?
Either way the fermentor ends up with lot more trub and spent hop residue that really cannot be good for your beer.

K

I dont think the additional speed of cooling would affect beer flavour. What is cold break and whom really understands it? Bullshite and then more bullshite about a break that you cant get rid off. Its there and its not hot and binding, its hmmmmmmmmmmm THERE.

 

[///]

Additional speed may not harm beer flavour, but slower speeds may via late kettle isomerisation and excess mallard reactions (just to name a few things).

Cold break is a series of by products that form (proteins usually) with the crash cooling of the wort. For understanding them, they add a postive to beer by ways of trace elements and nutrients needed by the yeast, but too much can impart off-flavours to the beer. These elements in shallower fermenters are also some of the first carried to the yeast head (i prefer to call it meringue not krausen) and some brewers skim off as they see them as attributable to harsh bitter flavours in there beer. Some brewers may also add a further step by using a centrifuge to remove these items on route to the fermenter. All I knows is that the damm stuff clagged up my u-bend on 2400l of ale today and I had to jam a 'persuader' up the clacker to unblock it without having 2400l of beer shoot out once cleared and give me a early shower. So it can be gotten rid of, but not usually by home brewers.

Target is to be off the majority of the hops and cooled within 60 minutes into the FV. Alot of research is being done by brewers in the US that use large amounts of whirlpool hops. As the amounts used are beyond what the large brewers would do, neglected was the impact of contact times to hops in the whirlpool on final bitterness. One brewer using mountains of hops have found that due to the amounts of late kettle hops used thier BU's were up 25% over expected gain. This has a plus as it means you can use less bittering hops, but also a negative as the beer is out of spec. Anyways, much of the opinion is to drop back on bittering hops and to have the transfer done with 60 minutes.

With a system like mine, this may not always be achievable with a lager where running at 30 hertz gives a tank temp for the wort of 13 C and a 1 hr 45 minute transfer. (it is bad practice to pitch warm and drop the temp, best to always be a few degree above and come up...) ... i'm caught with more contact time and higher BU's or lower contact time (due to faster pumping) and a warm wort above spec and poor fermentation management ....

Scotty