Do you Aerate your Wort ?

simmons · 07-07-2010, 05:53 PM

I have read in many books that it is good to Aerate your wort while it chills before you pitch your yeast. Does anyone have any experience with this. I'm wondering if there are any negative affects from this as well.

TheMethod · 07-07-2010, 06:12 PM

Yes, it is good to aerate your wort. There is only one time that you want to do this in the entire process and that is after you have cooled the wort but before you have added the yeast.

The yeast need the oxygen in order to do their stuff. Although you may be able to get by without aerating, it really does help.

Aerating while the wort is still hot will give you hot side aeration (what an apt term). This will give your beer an off flavor.

Adding oxygen after the yeast have started will also oxidize the wort in a bad way. So when you're transferring from primary to secondary or to the bottling bucket you don't want it to splash that much. This is also why bottle caps can have the little oxygen absorbing thing on the inside. It helps prevent oxidization of your beer.

In short: aeration after cooling but before fermenting is good. Any other time is bad.

tasq · 07-07-2010, 06:15 PM

Yes most people aerate. Boiling removes most of the oxygen from your wort. The yeast need oxygen to work. There are no negative effects at this stage in the game. After fermentation is when you want to be worried about introducing oxygen into your beer.

Hope this helps!

oceanselv · 07-07-2010, 06:15 PM

Be careful when aerating your wort when it is hot. Hot side aeration will increase melanoidins in your wort. These compounds will increase the staling in your beer. The best time to aerate the wort is when you have cooled to pitching temperature. At cooler temps the oxygen is not as reactive and does not oxidize the wort as much as at higher temps. There are a few ways to aerate as well. Many people use an aeration stone and pure oxygen; others use an aquarium pump and an aeration stone while others let their cooled wort to free fall into the fermenter and others use a stir plate with a stir bar for their yeast starter. I prefer to use the yeast starter method as this helps get the fermentation started quicker and minimizes any problems of contamination or off flavors.

psuchunk03 · 07-07-2010, 06:30 PM

i aerate with a sanitized whisk after i pour the chilled wort into my bucket, but before pitching the yeast. whisk until you're arm is going to fall off!

simmons · 07-07-2010, 06:47 PM

Thanks for all the replies this helps a ton.

SumnerH · 07-07-2010, 06:52 PM

Quote:

Originally Posted by oceanselv

Be careful when aerating your wort when it is hot. Hot side aeration will increase melanoidins in your wort.

Hot side aeration is nearly impossible to introduce at the home-brewing scale. I'd say it's a complete myth, but in a large commercial setup where there's compressed air/oxygen involved it might be possible to actually see some effects from it.

It requires vast amounts of aeration, though; Sierra Nevada and plenty of other breweries have their mash runoff cascading several feet into their kettle like a waterfall, with no ill effects. Heck, here's Allagash doing a hot wort transfer:
http://www.youtube.com/watch?v=wD_49kfVJeE#t=5m19s

Just sloshing things around at home isn't going to accomplish it.

**jakecpunut** · 07-07-2010, 07:02 PM

What about straining? I've been pouring my cooled wort into the fermenter through a strainer and that seems to aerate it pretty well... any thoughts on that?

rexbanner · 07-07-2010, 07:09 PM

Quote:

Originally Posted by SumnerH

Hot side aeration is nearly impossible to introduce at the home-brewing scale. I'd say it's a complete myth, but in a large commercial setup where there's compressed air/oxygen involved it might be possible to actually see some effects from it.

It requires vast amounts of aeration, though; Sierra Nevada and plenty of other breweries have their mash runoff cascading several feet into their kettle like a waterfall, with no ill effects. Heck, here's Allagash doing a hot wort transfer:
http://www.youtube.com/watch?v=wD_49kfVJeE#t=5m19s

Just sloshing things around at home isn't going to accomplish it.

I've also heard that post-fermentation aeration isn't really a cause for concern, either. I could be misinformed though.

I've always aerated just by vigorously pouring my wort from the kettle into the bucket, and then shaking it a lot. I've never had to repitch, and I've never had fermentation take longer than 24 hours to start.

HeavyBrew · 07-07-2010, 07:38 PM

Quote:

Originally Posted by jakecpunut

What about straining? I've been pouring my cooled wort into the fermenter through a strainer and that seems to aerate it pretty well... any thoughts on that?

+1.. I use one of those funnel strainers and I think that does a great job aerating the wort.