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 neva@whitelabs.com.
Alex at White Labs
nevalogic
yeastbuddy
Interesting. It seems just some O2 is good enough in a 5 gallon batch and there is not particular benefit to using a drop of olive oil nor is there an apparent negative effect.
You misspelled experiment in the title
Which yeast are you using?
I used WLP001 California Ale Yeast
not all homebrewers worldwide have access to bottled oxygen as is available in the US. this method if proved to be useful may be very beneficial to some of us.
I would say that a clean 1st gen pitch of yeast and not a slurry would make for a more accurate test. considering there will be less yeast multiplication with a larger colony of yeast and most of that yeast would not be effected by the lipid side of the experiment.
I also recently learned that wyeast smackpacks contain a lipid to combat low levels of oxygen in the wort.
Cheers
What I used was actually just a vial I placed into a flask so I could add the olive oil. I did the same for all of the vials so that they were treated the same. They oxygenation of first gen yeast is critical in building yeast cell walls and healthy yeast for future generations. This is when you’ll usually notice any oxygen or lipid deficiencies.
I haven’t seen the new belgiium article. Link maybe? Could you give some details on the process for emusifying in ethanol? I’m excited that the taste test was similar. Was there any noticible impact on head formation?
I am highly interested in results about this experiment.
When they will be published?
What was the gravity of the wort used for this experiment? I’m wondering if the differences will become more apparent in a high-gravity beer.
Here’s Grady’s paper.
http://www.brewcrazy.com/hull-olive-oil-thesis.pdf
Did I miss the results of the experiment?
And the results are????