Where do You Find Notable Difference with Oxygenation Stones?

[micraftbeer]

I've been trying out some oxygenation stones (both 0.5 micron + O2 tank, and aquarium pump + 2 micron stone) lately. My standing process is I pass the wort through a strainer as I transfer from kettle to fermentor and let that aerate/splash. I did two trials where I split my wort into 3 fermentors and had: 1) Wort transferred through strainer and splashed, 2) Strainer + Pure O2 oxygen stone, 3) Strainer + Air oxygen stone.

I did a simple Amber Ale recipe and WLP001 California Ale Yeast, and then a hoppy wheat ale with WLP008 East Coast Ale Yeast. I measured/tracked gravity in the batches using Tilt hydrometers, so I was able to see when fermentation started, ended, etc. and could compare the fermentation progress in that way. Per the plots below, I didn't really see much difference between these 3 methods. I did a taste test after and found no difference in the Amber Ale, and maybe a slightly detectable difference in the wheat ale.

I know a lot of people use oxygenation stones, so I'm trying to figure out a good experiment to test the benefit out. Interested in anyone's suggestions on particular styles/recipes/ingredients/processes where they think this would be a notable contributor.

 

[OG-wan Kenobi]

If I just splash my beer stalls every time usually around 3%, I use pure 02 for 90 seconds to get a complete fermentation I have never used an aquarium stone

 

[Comfort_Zone]

Usually I just make sure my wort gets maximum splashing. I've started pitching above 85 more often these days so oxygenation is sort of a waste.

 

[micraftbeer]

If I just splash my beer stalls every time usually around 3%

What do you mean it stalls "around 3%"? OG to your stalled gravity is around 3% ABV? What kind of beers/fermentation temperatures?

 

[SanPancho]

You will notice it more if you repitch your yeast. In a fresh yeast starter pitch it doesn’t make such a difference. Or in dry yeast.

 

[OG-wan Kenobi]

What do you mean it stalls "around 3%"? OG to your stalled gravity is around 3% ABV? What kind of beers/fermentation temperatures?

If I splash the beer my beer always stalls at around the 3% mark regardless of OG being 1.050 or 1.078 for me the result is the same I have had this happen with multiple beers and yeast strains wet and dry, I ferment at 68-70 I watch them take off and 24 hours later usually they stop dead in their tracks, so for me I don't splash anymore I just use pure 02 for about 80-90 seconds. I am sure the follow up will be this - Yes I do a starter on a stir plate and yes I also rehydrate my dry yeast.

 

[micraftbeer]

You will notice it more if you repitch your yeast. In a fresh yeast starter pitch it doesn’t make such a difference. Or in dry yeast.

Thanks, a light bulb just went off. From different feedback, it's become clear to me. The oxygen addition is needed/useful in more "challenging" fermentations. That is: 1) Harvested yeast instead of fresh, 2) Higher gravity worts, 3) Low temperature fermentations, 4) Larger volume of wort.

 

[SanPancho]

Exactly. The o2 is required for yeast to build cell wall membrane. Every time they reproduce they lose half. So larger cell count pitches need less as they need to multiply less to reach their fermentation cell count.

They also replenish in an o2 rich environment like an aerated stirred starter. So those need less too when they’re fresh.

And dry yeast is supposed to be well supplied before drying so that’s why they say it’s not necessary, only optional.

So if you don’t plan on repitching the yeast then a fresh starter and good splashing can be enough.

If you want to reuse yeast then a good supply of o2 ensures good viability and health going forward.