Am I retarded when it comes to oxygen?

[ajdelange]

Offering this as a hypothesis, not a fact: when oxygen is present the yeast stay in growth phase. When oxygen is depleted, they go into fermentation phase but with a larger quantity of yeast than would have been present w/o the O2. Thus the fermentation may take a little longer to start but should be more vigorous and thus complete sooner.

In my experience I get a substantial pH drop within 4-6 hrs with gas evolution usually underway within 12-18 hrs.

[BayouBrew]

I just got an O2 tank with a regulator that does read flow rate, and I also have a 0.5 micron stone. I will be using the setup on my next brew. So, if I remember correctly, I should run it at 1L/minute for two minutes while moving the stone around the bottom of the carboy. Is this what everyone is doing, or is the flow rate or time off (my memory may be totally screwed)?

[thatguy314]

Offering this as a hypothesis, not a fact: when oxygen is present the yeast stay in growth phase. When oxygen is depleted, they go into fermentation phase but with a larger quantity of yeast than would have been present w/o the O2. Thus the fermentation may take a little longer to start but should be more vigorous and thus complete sooner.

In my experience I get a substantial pH drop within 4-6 hrs with gas evolution usually underway within 12-18 hrs.

That's really interesting. A very reasonable hypothesis!

AJ, you always have some of the most insightful technical comments of anyone (I've been reading your discussion about water for vienna lager on HBD lately).

I'm going to have to buy you a few beers sometime and sit down and have a real conversation with you.

[ajdelange]

Will converse for beer!

[Charlie]

I have the basic cheap regulator from northernbrewer that doesn't give me PSI or flow rate. I was told to turn it up until I got bubbles, and that if the bubbles are breaking the surface I have it on too high.

Hmmm. There's a pressure gauge on my regulator, but I don't read it, and I don't think it's relevant. I start out with zero pressure in the secondary and turn the regulator screw until it's foaming vigorously, then leave it for 2 minutes.

I have oxygenated since my third brew (the one that wouldn't start. I had to get out the bicycle pump!). I usually have activity within 3 hours, and 10+ BPM within 5 hours rising to 50-90 BPM within 12 hours.

Charlie

[Hoppy Brewah]

This is an interesting discussion as O2 plays a large role in fermentation and thus the quality of finished beer. I am using a basic O2 regulator with a 0.5 micron stone and usually turn it on full blast for 30 seconds for 5 gallons of beer. Jamil says to use 1 L of O2 (1 L per minute for 1 minute). Is there a way to estimate how much O2 I am using? Should I turn it down and let it flow longer? I usually have krausen developing after 12 hours and vig_or_ous fermentation after 24 hours, so it seems to be working ok. Is there a gauge / regulator that works with the O2 bottles from the hardware store?

Thanks, Eric

[thatguy314]

I'm going to try turning it up all the way and giving it a little more time, 90-120 seconds.

I've found you can get a flowmeter for about $25. I'm not sure it's worth the investment. How much O2 will it save you in the long run versus turning the oxygen on all the way? It seems like that will make me get 2 or 3 fewer batches per can of oxygen, resulting in about, maybe, an additional can, or $8 per year.

[dstar26t]

I just recently got a DO meter and used it on my last beer, a Dopplebock. I have a regulator on the O2 tank and set it for 3 Lpm. The bernzomatic set-ups flow ~3.5 Lpm according to a visual comparison done by Wyeast. For 5 gallons of 1.082 wort @ 44F, a 60 second blast through a .5 micron stone gave 11.4 ppm dissolved oxygen. Another 30 seconds brought it to 17.5 ppm. I pitched a Jamil sized decanted starter and 12 hours later had krausen.