Aerated wort

[Teddie]

Hi all.. Its been a few years since my last batch of home brew.. I think i goofed.. I whisked my wort while in the ice bath.. I did this thinking it would speed up the cooling process. Recently i read that you should never aerate hot wort.. Has anyone experinced the results of doing this??

 

[BigFloyd]

Hi all.. Its been a few years since my last batch of home brew.. I think i goofed.. I whisked my wort while in the ice bath.. I did this thinking it would speed up the cooling process. Recently i read that you should never aerate hot wort.. Has anyone experinced the results of doing this??

You should be fine.

BTW, if you were using dry ale yeast, you really don't need to aerate.

 

[k_mcarthur]

The "new" school of thinking is that hot side aeration is a myth, but it's referring to aeration before the boil. I've never used dry yeast but yeast needs oxygen to multiply and boiling drives off oxygen. You can't aerate too much, but you can under aerate. Always, always aerate!

 

[Teddie]

I am using safale-05.. It started fermenting within 24hrs.. Very heavy fermention.. Had to remove airlock and use blow off tube it has settled nicely.. Primary was started on sept 14.. Checking fg this weekend.. Thks for the replys.. I was a little worried..

 

[eastoak]

The "new" school of thinking is that hot side aeration is a myth, but it's referring to aeration before the boil. I've never used dry yeast but yeast needs oxygen to multiply and boiling drives off oxygen. You can't aerate too much, but you can under aerate. Always, always aerate!

with dry yeast and only dry yeast you do not have to aerate although if you do it will not hurt anything. when i started brewing i bought something like 10 packs of US-05 on ebay and loved the ease of use and performance of dry yeast; no starters no aerating. i do own a O2 cylinder and a aerating wand that i use when i pitch slurry.

 

[BigFloyd]

The "new" school of thinking is that hot side aeration is a myth, but it's referring to aeration before the boil. I've never used dry yeast but yeast needs oxygen to multiply and boiling drives off oxygen. You can't aerate too much, but you can under aerate. Always, always aerate!

Here's the answer Danstar (maker of various dry yeasts) gives about aerating wort when using dry yeast:

Q.- I always aerate my wort when using liquid yeast. Do I need to aerate the wort before pitching dry yeast?

A.- No, there is no need to aerate the wort but it does not harm the yeast either. During its aerobic production, dry yeast accumulates sufficient amounts of unsaturated fatty acids and sterols to produce enough biomass in the first stage of fermentation. The only reason to aerate the wort when using wet yeast is to provide the yeast with oxygen so that it can produce sterols and unsaturated fatty acids which are important parts of the cell membrane and therefore essential for biomass production.

If the slurry from dry yeast fermentation is re-pitched from one batch of beer to another, the wort has to be aerated as with any liquid yeast.

When I use liquid yeast, especially for a lager, I'll hit the chilled wort with pure O2 through a 0.5 micron stone for 60-70 seconds at 2L/min. That's the only way I know of to get above the 8ppm level (the max you can get using air).

 

[PDX_T]

with dry yeast and only dry yeast you do not have to aerate although if you do it will not hurt anything. when i started brewing i bought something like 10 packs of US-05 on ebay and loved the ease of use and performance of dry yeast; no starters no aerating. i do own a O2 cylinder and a aerating wand that i use when i pitch slurry.

I don't understand why you don't want to aerate when using dry yeast. In order to produce esters, yeast need oxygen, and they need to be in growth phase. Esters are essentially a byproduct of the fatty acid synthesis required to expand the cell wall during reproduction, and this requires oxygen.

 

[PDX_T]

Here's the answer Danstar (maker of various dry yeasts) gives about aerating wort when using dry yeast:

Q.- I always aerate my wort when using liquid yeast. Do I need to aerate the wort before pitching dry yeast?

A.- No, there is no need to aerate the wort but it does not harm the yeast either. During its aerobic production, dry yeast accumulates sufficient amounts of unsaturated fatty acids and sterols to produce enough biomass in the first stage of fermentation. The only reason to aerate the wort when using wet yeast is to provide the yeast with oxygen so that it can produce sterols and unsaturated fatty acids which are important parts of the cell membrane and therefore essential for biomass production.

This is pretty interesting. I wonder if there are still enough short chain fatty acids stored in the yeast to produce significant ester character. Since I switched to dry yeast, I have aerated, so I guess I wouldn't notice a difference. I also don't brew much over 1.060, so I don't need pure O2.