Recirculate wort will cause oxidization?

[shawn]

I use a pump to recirculate my wort during the mashing, will the water drip from the top to the wort cause oxidization, which will cause my beer taste like wet cardboard ?

I thought by logic, before the boiling stage, oxygen doesn't matter because boiling will somehow release all the oxygen?

Actually in which stage we should be more careful about oxidization?

Thanks for any comments.

 

[MickDundee]

Only after fermentation isn't it? You are supposed to aerate the wort before pitching the yeast because the yeast needs oxygen to thrive?

 

[Spoon]

There's a theoretical issue called hot side oxidation. Where oxygen binds to compounds in the wort whilst hot and is released slowly (weeks/months) to ruin your beer in the future.

People who believe in it will do everything possible to avoid splashing in the mash or boil until the temp drops down to ambient at which point you oxygenate (not oxidise) which is just dissolving oxygen, not binding it to anything.

A few homebrewers have tried to cause it deliberately in experiments, and 'failed' to ruin their beer. So I think it's just a theoretical risk rather than an actual one.

The literal translation of Sparge from German is "to sprinkle", so clearly historical brewers never worried about it.

 

[Covrich]

Yeah I think a lot of people think its a myth (hot side oxidation).. I don't recirculate but I wouldn't worry about it

 

[MyQul]

I definately think hot side aeration is a myth. When I no chill I just use a jug to transfer (read: chuck) my wort from the pot into the cube. Initially there's loads of foam and I've never experienced any wet cardboard off flavours in my final beer

 

[Keviebaby]

When I brewed a few years ago I did have a brew or two that definately had the cardboard taste. I used a three tier system so transfering from the mash tun to the boil kettle did cause splashing but I'm not convinced at all that the off taste was down to HSA. It's more probable that I messed something up during fermentation or kegging.

I wouldn't worry about it, beer is quite forgiving really. Sanitation aside, it's not that easy to really ruin a brew.

Kev.

 

[DoctorMick]

Before I'd heard of hot side oxidation I used to start airaeting before the wort had cooled below the min temp for hso (can't remember what it is) br since I learned about it I cool for longer before airaeting. It hasn't made the blindest bit of difference mind. :lol:

 

[mike-os]

if it were true would HERMS work?

 

[MickDundee]

Before I'd heard of hot side oxidation I used to start airaeting before the wort had cooled below the min temp for hso (can't remember what it is) br since I learned about it I cool for longer before airaeting. It hasn't made the blindest bit of difference mind. :lol:

I'd never heard of it until today, and I usually transfer my boiling (or 80C with late additions) wort to the FV before cooling and deliberately make sure it was splashing to start off the aeration. Mainly because we have awful kitchen taps and it's awkward to feed the hose for my chiller through the window.

 

[shawn]

Wow, learn a lot of from you guys, thank you so much, i think i will not bother the hot side aeration again. thanks again..

 

[GHW]

Grainfathers deliberately recirculate as part of the process and they don't oxidise wort. I don't think it's an issue at all.

 

[Simonh82]

I was listening to a podcast yesterday and they said that hot side oxidisation is real but for it to be noticeable you would have to have everything tiny part of your process nailed down. Any other variation in your process would likely have a bigger impact on flavour than HSO.

It is also more likely to be an issue in a really light larger (think coors light) than something with any flavour. If you've chucked in a load of hops in or a strongly flavoured malt then you would never be able to pick it up.