cooling the wort

[Ray Mason]

Hi guys, After the boil where's the best place to cool the wort? I have an immersion cooler which i sterilise in the boiler but should i move the wort into the FV then cool it to fermentation temp or is it okay to cool it in the boiler then move it to the FV, or doesn't it matter? My cooler takes about an hour to get the wort down to fermentation temp so is it doing any long term harm to leave it with the hops immersed in it for that long while it cools? Ray.

[MightyMouth]

You want to cool it in the boiler so that the break material will be filtered out by they hops as much as possible. It is not necessary to do this but why not if it reduces the break in the fermenter. Obviously if you use an in-line cooler you don't get this benefit and I am not sure how great it would be in any case.

[Cheshire-cheese]

Also, if you cool in the boiler, you can tap it off into the FV allowing a good drop between the tap and the FV to get some aeration as it splashes into the FV.

[salnajjar]

The more messing with it you do after the boil before chilling it the more chance you have of increasing the oxidisation. I'm no expert (only done 3 AG brews so far) but with all the reading up I've done on here and elsewhere it seems that most important thing after boiling is to try and chill it as fast as possible.

[Ray Mason]

Thanks guys, just clarifying things. I would agree that today’s method of moving the wort to the FV after cooling seems to be accepted practice but after being given Dave Line’s Big Book Of Brewing this appears to be contradicted. I know it’s an old book but it was considered the ‘Bible’ of home brewing at the time, states that the wort should be removed from the boiler ‘after a few minutes, when the hops have settled to the bottom’ and cooling done in the FV. I know it was first published in 1985 and things move on, processes evolve, but for many it was, and is, the definitive book. I guess I’ll have to scour the shelves for something a little more modern. Any suggestions?

[MightyMouth]

Does the Dave Lines book mention Immersion Chillers or Counterflow Chillers or is it just a case of putting the FV in the Bath full of cold water? If you aren't using an IC then cooling in the the FV is the way to go but if you are using a IC then you do it in the boiler for a number of reason. One is that you can place the IC in the boiler 15 minutes before the end of the boil to sterilize it. Two is that you to get the wort cooled before transferring in order to eliminate the chance of hot-side aeration. Third is, as I stated before, to leave as much break material as possible in the boiler and there are probably a number of other reason. You could read How to Brew - by John Palmer but it is long and drawn out for my liking. BYOBRA is a great resource but doesn't really deal with the whys so much as the hows.

[196osh]

The more messing with it you do after the boil before chilling it the more chance you have of increasing the oxidisation. I'm no expert (only done 3 AG brews so far) but with all the reading up I've done on here and elsewhere it seems that most important thing after boiling is to try and chill it as fast as possible.

Not exactly sure what issue there would be with oxidation...

Pre fermentation you have to aerate the wort, some people use pure oxygen to aereate.

So I dont know why that would be an issue pre ferment. As the yeast will metabolise all of the oxygen in the wort to divide.

[MightyMouth]

The more messing with it you do after the boil before chilling it the more chance you have of increasing the oxidisation. I'm no expert (only done 3 AG brews so far) but with all the reading up I've done on here and elsewhere it seems that most important thing after boiling is to try and chill it as fast as possible.

Not exactly sure what issue there would be with oxidation...

Pre fermentation you have to aerate the wort, some people use pure oxygen to aereate.

So I dont know why that would be an issue pre ferment. As the yeast will metabolise all of the oxygen in the wort to divide.

You don't aerate until after you have chilled, if you aerate while hot it can cause oxidation amongst other things.

[196osh]

You don't aerate until after you have chilled, if you aerate while hot it can cause oxidation amongst other things.

Why?

What differnce is there aerting hot wort vs cool wort? You have to oxygenate the wort anyway post boil. Why would the yeast not metabolise the oxygen that was added to the wort whillst hot when they were dividing?

[trucker5774]

You don't aerate until after you have chilled, if you aerate while hot it can cause oxidation amongst other things.

Why?

What differnce is there aerting hot wort vs cool wort? You have to oxygenate the wort anyway post boil. Why would the yeast not metabolise the oxygen that was added to the wort whillst hot when they were dividing?

I was wondering about this too.............I was about to start a new post. I have not come across this before.

[MightyMouth]

I am not sure how much bearing it has on Home Brewers as we probably aren't likely to introduce enough oxygen to cause a problem unless you let the wort splash as you might when it falls from the boiler into the FV but hot side aeration causes Oxygen to bind with compound in the wort which then can break down some time after bottling, causing oxidation of the beer over time. This is apparently only a problem over about 27c.

[flything]

You don't aerate until after you have chilled, if you aerate while hot it can cause oxidation amongst other things.

Why?

What differnce is there aerting hot wort vs cool wort? You have to oxygenate the wort anyway post boil. Why would the yeast not metabolise the oxygen that was added to the wort whillst hot when they were dividing?

I was wondering about this too.............I was about to start a new post. I have not come across this before.

Hot Side Aeration, due to the fact the wort is hot it's possible to oxidise the melanoidins and they then lose their ability to act as anti-oxidants in the beer once it's fermented out, this can lead to faster spoiling and stale flavours, although it's a hell of a lot more complicated than that. Suffice to say, if you can avoid thrashing your mash, and overly slashing your hot wort around then it's probably a good idea, but I wouldn't panic about it.

Another reason to cool your wort quickly in the kettle, is to stop volatile hop aromas being lost, getting all your wort down to below 80c as quickly as possible helps prevent this.