Olive Oil vs Aeration Experiment

From the Lab:

We’ve had so many questions from commercial and homebrewers alike, about whether adding olive oil to wort can take the place of oxygenation/aeration. We’ve read the New Belgium study, but we decided to find out for ourselves, on a 5 gallon scale. We know that yeast need lipids to build new cells and promote a good fermentation. We also know that they need oxygen (in the range of 8-10ppm) as building blocks for this, but the theory is – what if we provide the lipids themselves?

I did two sets of trials, to get some repeatable (hopefully) data. I brewed two 20-gallon batches of English IPA and split each batch into 4 fermentors. One fermentor was dosed with 5ppm oxygen and one with 10ppm oxygen. Then I used olive oil to one fermentor and a product called Pactoferm (from Birko) in the fourth, an anti-foam product that is made with canola oil. Since I had calculated the olive oil needed for one fermentor to be the equivalent of a drop, I used New Belgium’s method to ensure the addition went smoothly. I emulsified the oil in some 200proof ethanol, then added that to a yeast slurry on a stir plate for four hours. To keep the experiment controlled, I put the other 3 yeast slurries on a stir-plate as well. If you’ve been to the tasting room, tried the beers, and looked at the data, you’ll see that all the fermentations were very closely matched, even the one with lower oxygen.

I think what will be more interesting to see, and a new trial will be done, is how these methods affect later generations – second and third generation fermentations. I think we’ll see more variation. So for the next one, I’ll do several brews. I’d also like to implement a method for the olive oil introduction that someone without an outfitted lab would use. If you’ve done it before, I’m interested to see how you did it! Send any emails to [email protected].


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Replacing oxygenation with olive oil is a big step for homebrewers, and will not be easily accepted unless it is shown to be superior. Most people who homebrew will wait for a consensus to be reached, or at least for a publication explaining why olive oil is superior to oxygenation, before they make the change. You know, change doesn't come easily when you've got something that works well already.

However, I find these studies and papers quite interesting, and will be following this topic as it evolves. I can't say that I'll be switching to olive oil over oxygenation any time soon though, lol. I would require evidence that best practice has moved from oxygenation to olive oil, and that this new best practice was feasible and practical for the homebrewer.

Since I'm so far away (Massachusetts) I haven't been to the tasting room, tried the beers, OR seen the data. Is there any chance you could post it here, or post a link to where it is so I can see your result? I'd be forever in your debt :)

Wouldn't the stir plate add oxygen, thereby defeating the purpose of the experiment?