Is Aerating Wine/Beer solely for yeast health?

[Matt723]

I've been steadily fermenting Beer/Cider for the past 6 months and I have always strained myself when it comes to aeration. I'm not sure if I am aerating to the right levels but each of my fermentations have worked out fine. Typically my fermentations start within 24 hours.

Am I right to assume I am reaching sufficient levels of aeration? I am also assuming that the only reason for aeration is to promote yeast health, is that correct? Are there downfalls of not aerating, like stressing the yeast? Does aerating have any effect on anything other than yeast health?

Thanks for your input!

 

[dbreienrk1]

I've been steadily fermenting Beer/Wine/Cider for the past 6 months and I have always strained myself when it comes to aeration. I'm not sure if I am aerating to the right levels but each of my fermentations have worked out fine. Typically my fermentations start within 24 hours.

Am I right to assume I am reaching sufficient levels of aeration? I am also assuming that the only reason for aeration is to promote yeast health, is that correct? Are there downfalls of not aerating, like stressing the yeast? Does aerating have any effect on anything other than yeast health?

Thanks for your input!

How do you aerate?

Wort is aerated so the yeast have the necessary levels of oxygen to properly reproduce. Without areation the yeast would consume all available oxygen and stop reproducing. Then there would not be enough yeast to achieve your desired FG.

Palmer wrote:
"Yeast need oxygen to synthesize sterols and unsaturated fatty acids for cell membrane biosynthesis. Without aeration, fermentations tend to be underattenuated because oxygen availability is a limiting factor for yeast growth—the yeast stop budding when sterol levels become depleted. Higher gravity worts need more yeast for proper fermentation, and thus need more oxygen, but the higher gravity makes it more difficult to dissolve oxygen in the first place."

 

[Matt723]

I aerate with a wine degassing stick I put on my drill in addition to splashing it into the fermenter when filling. Sometime I'll also shake it up.

So it sounds like your saying aeration is strictly done for yeast health and nothing else. If I were to do a yeast starter would this mean I could get away with less aeration?

Also, I was told never to aerate wine... is that correct?

 

[dbreienrk1]

I aerate with a wine degassing stick I put on my drill in addition to splashing it into the fermenter when filling. Sometime I'll also shake it up.

So it sounds like your saying aeration is strictly done for yeast health and nothing else. If I were to do a yeast starter would this mean I could get away with less aeration?

Also, I was told never to aerate wine... is that correct?

I don't know anything about making wine...

No, even if you use a yeast starter you should still aerate your wort. You will get faster times and reduce the likelihood for a stalled fermentation.

I guess you could call it "yeast health" but if you get scientific it is much more than that. Read Jamil's book called "Yeast." That will give you a pretty good understanding of everything involved with yeast and brewing. If you want more info, get a microbiology textbook.

 

[Tinga]

I would say yes, aeration is soley for yeast health. However, yeast health has the biggest impact on flavor over every other variable.

 

[shawnbou]

Also, I was told never to aerate wine... is that correct?

I've never made wine, but I've made mead with wine yeast, and the techniques are similar, because the needs of the yeast are the same. My understanding is that you should aerate wine periodically during the initial few days of fermentation, to let air in and also to let CO2 out - the degassing whip you have for your drill is made for exactly this (but also works very well for aerating beer wort). For my meads, I have stirred them with a whip at least once a day for the first week, and I have had excellent results.

Once the bulk of fermentation has ceased, then just like beer you do not want to aerate because this will oxidize the wine.

However, you may want to post this question in the wine forum and get the opinion of a better expert than I.

Also, making a yeast starter does not override the need for aeration of wort before pitching. Aeration is essential for yeast health, and that is the most important factor in proper fermentation. If you wanted to get really technical, a yeast starter does not promote yeast health so much as it increases yeast population.

 

[snafu858]

Olive oil as a "substitute" for aeration in beer:
http://www.haandbrygforum.dk/gallery/albums/userpics/10002/Olive-oil-thesis.pdf

 

[Matt723]

Olive oil as a "substitute" for aeration in beer:
http://www.haandbrygforum.dk/gallery/albums/userpics/10002/Olive-oil-thesis.pdf

That's a really interesting study, how come people don't mention this? Way easier than shaking a 5 gallon carboy!!!

 

[FightingBob]

Olive oil as a "substitute" for aeration in beer:
http://www.haandbrygforum.dk/gallery/albums/userpics/10002/Olive-oil-thesis.pdf

That's super interesting. How did you find that?