Is wort aeration necessary?

[Silver_Is_Money]

With all of the recent talk about the benefits of low oxygen brewing, is it possible to completely eliminate the aeration step (which occurs either just prior to pitching or immediately post pitching yeast) and still get a complete fermentation? This old dog was taught 25-30 years ago that aeration is a vital step and lots of it must occur. The more, the better. Is this yet another myth from times past?

 

[UnrestrictedBrewing]

There is a great article at http://brulosophy.com/2015/10/19/wort-aeration-pt-3-nothing-vs-pure-oxygen-exbeeriment-results/ that basically concludes that you can make beer without aeration but you are going to make it faster and better with aeration.

 

[DaWhip]

Aeration is not critical in making beer, but it is very important in making good & repeatable beer. This becomes even more true if you are reusing yeast as the yeast from the oxygenated brew will finish much healthier than if not. I made a lot of drinkable beer with no aeration before I got deeper into brewing, but aeration and appropriate pitch rates have definitely been a game changer.

The yeast use the O2 to produce unsaturated fatty acids, which they need for growth, so you could theoretically mitigate some effects of low 02 by adding unsaturated fatty acids to your wort (leave lots of trub, olive oil, fish oil?) and/or pitching a lot more yeast initially. I think both of those options are difficult to quantify and if you are off, you risk leaving some type of oil in your finished product. With aeration, the yeast get to manage the production appropriately themselves.

 

[ajdelange]

I had a situation once in which a fitting cracked so that the oxygen going through the flow meter (which indicated normal flow) went out through the crack and not into the fermenter (SS so I didn't notice lack of bubbles inside). Based on that experience I would say YES!

 

[GHBWNY]

There's a very thorough discussion of aeration pro's and con's in a thread on here called, "How Do You Aerate?"