Fermentation Time vs Oxygenation

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gonefishin2

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I have been tweaking my session IPA recipe. I brewed a batch two weekends ago. I was oxygenating the batch and realized I was out of 02, so I hooked up my old air pump for 5 mins.

I sort of created a natural experiment because I changed the recipe and process so little from the previous batch. The only material difference was the oxygenation method.

There was a significant impact on fermentation time. Check out the graph i put together to show this difference!

I thought this was pretty neat and worth sharing w the community.
 

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Pretty much as expected, but still always good to see the CW confirmed :)
iirc there are lots of similar experimental results in Yeast, that show eventually the low/no-oxygenated half batch catches up to the gassed one...

Cheers!
 
Yeah, not so sure it is exactly that simple. I just had a similar situation where I was brewing a beer that I have made dozens of times - almost everything the same except... ... because of the whole COVID thing.. ..I had run out of O2 and not been able to replace it. I thought I needed a bit of a boost because of the lack of O2, so I decided to turn the yeast I had set aside into a vitality starter made 3 hours before pitching. This yeast absolutely ripped through the beer to final OG faster than ever, even though my aeration was just letting the wort fall into the fermenter. There are many variables to fermentations that we don't always appreciate.
 
Yall are totally correct. This is no experiment, however I thought it was an interesting look.

Another note—I overbuild and harvest my starters, so this yeast came out of the same pack.

I’m drinking the beer now and there are no perceivable off flavors. Another interesting observation.
 
So much for LODO process then. Does faster time to FG mean better tasting IPA? What does it matter how fast I get my IPA (or any wort) to FG?

I also thought O2 was an IPA flavour killer?

I know my IPA in bottle definitely loses sharpness after a little while. At least, I perceive it as such, but I usually drink through my bottles so fast its hard to really tell. I am informed, on this very board, that it is a result of oxygenation.
 
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So much for LODO process then. Does faster time to FG mean better tasting IPA? What does it matter how fast I get my IPA (or any wort) to FG?

I also thought O2 was an IPA flavour killer?

I know my IPA in bottle definitely loses sharpness after a little while. At least, I perceive it as such, but I usually drink through my bottles so fast its hard to really tell. I am informed, on this very board, that it is a result of oxygenation.

Um you may have a couple things conflated. Lodo brewing isn't the same thing as oxygenating your wort, or not, for yeast health.
 
Um you may have a couple things conflated. Lodo brewing isn't the same thing as oxygenating your wort, or not, for yeast health.
Not sure I did. Many Lodo proponents keep oxygen exposure to a minimum throughout the entire process, even reducing boil to a steady roll. Most of what I posted can be found on these pages in some form.

I'd still ask what benefit is derived from oxygenating the wort and arriving at FG earlier.

For the record, I swish my ferment and aerate as much as possible simply to make sure yeast gets going. Guess I am just pointing out some conflicting opinion.
 
Not sure I did. Many Lodo proponents keep oxygen exposure to a minimum throughout the entire process, even reducing boil to a steady roll. Most of what I posted can be found on these pages in some form.

LODO proponents strive to keep O2 out of the entire process, except for oxygenating the wort when pitching yeast.
 
Another note—I overbuild and harvest my starters, so this yeast came out of the same pack.
The first batch got freshly-propagated yeast and the second batch got yeast that was stored for some period of time? Or was it propagated again, under more-or-less identical conditions?

I'd still ask what benefit is derived from oxygenating the wort and arriving at FG earlier.
Quick fermentation is generally correlated with healthy yeast, and healthy yeast generally produce fewer off-flavors (at the end of fermentation). With the right process this can ultimately lead to a better tasting beer with less oxidation.
 
The first batch got freshly-propagated yeast and the second batch got yeast that was stored for some period of time? Or was it propagated again, under more-or-less identical conditions?

My SOP is to overbuild a yeast starter before each batch. The first batch was probably gen3 and the second would be gen4–each with its own starter.

To add an interesting layer to the conversation: I recently completed a sour where I pitched lacto (i made a starter for the lacto) for about 24 hrs, and purged the headspace of oxygen (fermenting in corny). Then i pitched a pack of Voss and again purged the headspace of o2. The voss performed swimmingly and really put off a ton of the orange flavor it is known for! Great beer. It was an 8 gallon batch.
 
First cool comparison and thanks for sharing it.

I read OP that you are drawing conclusion that the comparison favors use of O2 and assume you plan to stick with that technique. Given both beers came out tasting as expected and understanding no side by side is possible, I'd argue the data actually favors the yeast that managed the higher attenuation which is the more objective measurement. TBH both of these are on low side for WLP090 (the oxygenated beer is actually below the low end of the published range for the yeast), but assume you are mashing very high since it is a session ale.

FWIW 90 seconds of pure O2 in a 1.045 beer sounds like a lot to me. I do that much in 17 gallon batches of higher strength beers and call it good enough.
 
The first batch got freshly-propagated yeast and the second batch got yeast that was stored for some period of time? Or was it propagated again, under more-or-less identical conditions?


Quick fermentation is generally correlated with healthy yeast, and healthy yeast generally produce fewer off-flavors (at the end of fermentation). With the right process this can ultimately lead to a better tasting beer with less oxidation.
If you are adding oxygen to aid the yeast/fermentation along, then what difference if your yeast is unhealthy to begin with? Does the O2 somehow stop it producing these off flavours? Not being facetious. Wanting to understand.
 
If you are adding oxygen to aid the yeast/fermentation along, then what difference if your yeast is unhealthy to begin with? Does the O2 somehow stop it producing these off flavours?
Oxygen isn't necessarily a cure for unhealthy yeast because the culture may deplete other nutrients while attempting to grow (including nitrogen, vitamins, and/or trace minerals).
 
If you are adding oxygen to aid the yeast/fermentation along, then what difference if your yeast is unhealthy to begin with? Does the O2 somehow stop it producing these off flavours? Not being facetious. Wanting to understand.

Healthy yeast will usually attenuate more and do a better job of cleaning up VDK’s. Those two things alone have a big effect on the beer taste. It’s not that faster ferments are better, you want healthy yeast which just happen to ferment faster.
 
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