Hello, During my cooling phase of the last couple of all grain brew days, I have been running my wort through a pump - to a plate chiller and back into my brew kettle to whirlpool. During the last minute or 2 of cooling, I deliberately Aerate the wort by putting the hose a few inches above the wort line and directing the cooled wort directly down to create a large amount of aeration. Then turn my pump off and let the beer flow by gravity into my primary fermenter. I do not do any additional shaking of my fermenter or add oxygen any other way. I have not experienced any oxidation flavors and I have never had a problem with my yeast fermenting the wort. I have been looking around on forums and homebrew websites to see if anyone else does this, and have not found anything about it.
Am I getting extremely lucky in not getting any oxidation off flavors? Does anybody else do this? Am I worried about nothing? Does anyone have any reasons why i should stop doing this?
If you get the wort cool before you recirculate with splashing, there should be no problems.
One guy I know will back off the inlet to the pump a few partial turns until he sees small bubbles come out the other end, doing this just before chilling is done, and he often pitches the yeast while this is going on.
I pump wide open into the fermenter, which causes a lot foam, then pitch the yeast. The yeast will consume the O2.
Am I understanding that you are doing this aeration technique on the hot side while the wort is cooling? Hot side aeration may or may not be a concern depending on if you believe it or not. I personally think it is not a big concern but still think it is best to minimize as much as possible. While I don’t think HSA will ruin a beer I know there has been at least 1 test that has shown that it may change a beer. So for consistencies sake I’d ry to avoid it.
The other concern I would have would be wether you are getting enough aeration. I would personally go the extra step to find a way to add additional aeration. Perhaps a “mix stir” after you collect you full volume in the fermentor just to be sure you are aerating properly (though I have to admit, I personally think pure o2 and diffusion stone is the best way to assure proper aeration.)
Thanks for all the info everybody. To clarify, I don’t intentionally aerate until it has cooled to about 90 degrees F. Once I hit 90, I keep recirculating until I hit 80-85 ish degrees. which is usually just another minute or 2.
I don’t see any problems with your process as long as it is sufficiently aerating your beer. I’m not sure you are aerating the beer as much as you may need to though.
Call me paranoid. I don’t uncover my beer to stir. Once I hit “flameout” I play defense. Beer is exposed to sanitized surfaces/air only as much as possible. There is a small opening in my fermenter for my O2 line and stone, which gets covered with foil.
I aerate right before pitching because the wort coming out of my kettle is way too hot to pitch yeast into and 1)it won’t hold as much o2 as it will once it’s colder and 2) what it does take up will just leave again in a very short time.
As far as HSA goes, I’ve only got one kettle so when I am spargeing I run off into buckets and then add the sparge water. I put my kettle on the burner, pour in the first runnings and start heating and run off the second runnings into the bucket which is again poured into the kettle. I’ve not noticed an issue so far but that is just one anecdotal experience so take it as it is.
HSA was a boogeyman when I started brewing. Unless you are making very light lagers and looking for a year shelf life, one should not get too concerned. Charlie Bamforth says there are many other things that we should worry about and get control of before we worry about HSA.
the concern (assuming there is any) is with reaction products that are created quickly so any splashing hot side can introduce o2 which will begin oxidizing things. the o2 will be driven off again during the boil but the products of those reactions won’t. However, as Mr. Bamforth says, while it is a real concern for in pro breweries for the homebrewer it is not going to make a noticeable difference compared to many many other factors.
I simply cool with a copper imersion chiller until at pitching temp, then open the boil kettle drain valve to drain thru a fine mesh strainer and splashing the wort into fermenter. I end up with A LOT of foam on top of the wort that I pitch my yeast into. I get pretty quick starts, a healthy kreuzen, and active complete fermentations this way. Who knows if it’s “enough” oxygen but it seems to work great.
Immersion chiller goes in the kettle 10-15 minutes before end of boil. At flameout I put the lid on over the IC and cover any gaps with foil or a towel soaked in Starsan while the IC is running. I will occasionally lift the lid to stir with the IC, but I don’t leave it uncovered, even though it would cool much faster. After cooling I drain to fermenter and aerate with oxygen immediatley prior to pitching yeast. Now that I have pumps, I can recirculate my wort with a pump while cooling, which should really speed things up. Will find out Saturday.
It started when I used to brew outside and a big fat fly flew into my kettle while cooling. Batch after that a mosquito took a dive bomb into my chilled wort. That was enough for me to drape some towels over the kettle and keep a lid on.
I recirculate with a pump and the Jamil Z return arm, with cool tap water in the winter 10 gallons of wort cools to 65F in 14.5 minutes with a 50 ft. 1/2 inch immersion chiller.