Olive oil for yeast and experimentation results

[Killrb13]

Has anyone been using olive oil as a yeast nutrient? When I started brewing beer years ago, I did extensive research on yeast (Saccharomyces cerevisiae) and their life cycle. I read a few articles on the use of olive oil in the wort as a supplement to aeration (or lack thereof for people without pure oxygen and bubble stones) and found that a small amount of olive oil (2-3 drops per 5gal) helped with low oxygen saturation in the wort. The Linoleic acid and sterols in the olive oil would help the yeast to propagate (do the nasty and reproduce) much the same way they use oxygen.

Me and a fellow brewer have experimented with multiple batches of beer and have have found favorable results. We did around 8-10 batches with (2) 5 gal carboys, one with olive oil and one without. Both were aerated prior to splitting into separate carboys and kept within one foot of each other for temperature sake and in identical carboys. We did our best to add even amounts of pre-started yeast cultures (starters) made with the same wort they would be pitched to. The carboy with the olive oil drops always (not sometimes) started and finished first and with a FG the same or lower that the control (carboy without olive oil). Me and my fellow beer maker concluded that olive oil definitely had an impact. The one thing we also noticed is that the ferments that got a little warm and prone to H2S gassing had milder H2S notes on the olive oil samples.

I would be curious to see if anyone has done a similar setup or if anyone currently uses olive oil in their ferments. Questions, comments or feedback?

[Killrb13]

I now do all my fermentations with olive oil.

[skow69]

Hydrogen sulfide? I didn't know that was a product of fermentation. That's pretty scary.

[Killrb13]

Yep, they tend to produce low amounts in a nitrogen deficient environment or when heat stressed. Adding DAP, proper aeration and temperature control will keep the yeast from stressing and keep the H2S levels to a manageable level. High gravity ferments tend to get a little gassed as well Ive noticed since starting to do high SG mashes a while ago...

[skow69]

Ya, those are the usual suspects for stressed yeast off flavors, all right. And pH level. How high of gravity are you talking?

[bellybuster]

there's a large study out there somewhere regarding olive oil and fermenting. Its greatest value if I remember was aeration. I'll se if I can find the thread from my old brewing club

[Killrb13]

Yeah, there is no substitute for proper aeration. If you don't have a proper setup to aerate (shaking method only) the olive oil is a good way to supplement in my experience.

[Killrb13]

Ya, those are the usual suspects for stressed yeast off flavors, all right. And pH level. How high of gravity are you talking?

1.10 area and up

[masonsjax]

I use the olive oil trick often, but always on higher gravity batches. 2-3 drops in 5 gallons is actually much more than enough. Most people dip the end of a toothpick in oil and swish it in the wort which is sufficient. The only issue with using more is that the oil survives fermentation and lowers the surface tension of the beer, thus reducing the head retention. Not a problem in distilled product.

[dstaines]

I have used olive in distillation specifically to reduce the surface tension, as an anti foaming agent. Added less than half a tsp at the time that I charge the boiler. Now I use FermcapS both in the still boiler, and in brewing in the BK and primary fermenter to prevent blow off. Never used oil in the fermenter

[T-Pee]

Ya, those are the usual suspects for stressed yeast off flavors, all right. And pH level. How high of gravity are you talking?

1.10 area and up

Too damned high. Get it back down to 1.090 max and you won't have these problems in the first place. Quality over quantity.

tp

[3d0g]

New Belgium brewery did some fairly extensive tests on olive oil oxygenation when the hype hit the brewing scene years ago. They've got some pretty damn sophisticated labs on-site and they concluded olive oil did little to nothing for ferments.

[Killrb13]

Ya, those are the usual suspects for stressed yeast off flavors, all right. And pH level. How high of gravity are you talking?

1.10 area and up

Too damned high. Get it back down to 1.090 max and you won't have these problems in the first place. Quality over quantity.

tp

Quality over quantity? I get both when distilling 15+ percent washes to 92%. If I was pot stilling or brewing beer then yeah I can understand...

[Killrb13]

New Belgium brewery did some fairly extensive tests on olive oil oxygenation when the hype hit the brewing scene years ago. They've got some pretty damn sophisticated labs on-site and they concluded olive oil did little to nothing for ferments.

I believe they used olive oil as a replacement not as a supplement like I'm describing.

[Killrb13]

All I'm saying is I ran my own experiment and had favorable results.

[3d0g]

All I'm saying is I ran my own experiment and had favorable results.

Not at all saying you don't. In spite of the pro findings, there's still many homebrewers that swear by it.

[heartcut]

I swear by olive oil at the start of fermentation, in some cases. Without oxygenation 1/2 tsp will disappear without a trace and a few drops in a aerated batch helps smooth the flavors out. Don't think it's better or worse, just a different way to get there and slightly different flavors. Pushes the Nasty-Complex-Smooth-Boring score towards the smoother side if that's where you want to go.
I can see how a brewery trying to duplicate the flavor of an established multi (balanced) off taste brew like a Belgian recipe might not be impressed, but olive oil is a valuable tool for me.

[Killrb13]

I swear by olive oil at the start of fermentation, in some cases. Without oxygenation 1/2 tsp will disappear without a trace and a few drops in a aerated batch helps smooth the flavors out. Don't think it's better or worse, just a different way to get there and slightly different flavors. Pushes the Nasty-Complex-Smooth-Boring score towards the smoother side if that's where you want to go.
I can see how a brewery trying to duplicate the flavor of an established multi (balanced) off taste brew like a Belgian recipe might not be impressed, but olive oil is a valuable tool for me.

I have never used a bubble stone for fear of contamination and the fact that it is just one more step to add during brew day. Shaking the wort as a form of aeration is really a poor way to aerate see below:

Oxygen in ppm (parts per million)
Shaking: 2 ppm
Aquarium pump: maximum of 8 ppm
30 seconds pure O2: 5 ppm
60 seconds pure O2: 8-10 ppm
2 minutes pure O2: greater than 14 ppm
The above pure O2 is assumed to be one liter per minute.

For those of us that prefer the easy way olive oil is worth looking into in my opinion. Also, as heartcut has stated the flavor does tend to be a little smother on the palette.

[Killrb13]

Here is the paper done by Grady Hull, brewmaster at New Belgium if anyone is interested in reading. The study also seems to be primarily about the storage and starters for yeast...
http://www.brewcrazy.com/hull-olive-oil-thesis.pdf


The conclusion for the lazy folk lol:

The idea of supplying yeast with the unsaturated fatty acids that it requires for
membrane health and growth is an intriguing possible alternative to the practice of
wort aeration. It has been proven that during the dormant phase of storage yeast
cells will take up fatty acids such as linoleic acid (Moonjai, 2003a). It is commonly
accepted that wort aeration is necessary for yeast growth but also that oxygenation
of the product reduces flavor stability. If the yeast is supplied with the olive oil during
storage, normal fermentations can be achieved with improved flavor stability. The
addition of olive oil to storage yeast in this study showed that consistent, complete
fermentations of acceptable flavor quality and improved flavor stability can be
achieved. However, these test fermentations were slower and produced an
increased amount of esters compared to the controls. Although the finished product
was significantly higher in ester content, it was not determined to be out of
specification and was actually preferred by the internal flavor panel. The goal of
improving flavor stability was achieved but at the cost of increased esters and slightly
slower fermentations.

[bellybuster]

the Grady Hull paper is much disputed as it was basically a pepsi/coke taste test, anyone who has ever entered a beer in a competition can attest to the value of taste as a scientific gradient.

Ive been trying to find the paper that has absolute scientific evidence of the aeration value of olive oil. No luck so far but I'll find it. I have it somewhere in the deep dark annals of my hard drives

[Killrb13]

the Grady Hull paper is much disputed as it was basically a pepsi/coke taste test, anyone who has ever entered a beer in a competition can attest to the value of taste as a scientific gradient.

Ive been trying to find the paper that has absolute scientific evidence of the aeration value of olive oil. No luck so far but I'll find it. I have it somewhere in the deep dark annals of my hard drives

50% of the time it works all the time lol. But seriously, in doing the experiments we did, there is definitely something to it.

[skow69]

So what's the magic for olive oil? Why not rape seed oil or avacado?

[heartcut]

Tried olive oil and it worked. Probably other ones will work as well, but I always have olive oil in the pantry.

[Killrb13]

So what's the magic for olive oil? Why not rape seed oil or avacado?

Because of the concentration of linoleic acid that olive oil has along with other sterols. From what Ive gathered olive oil has more than others.

[waster]

I never did comparison studies, but stopped using olive oil when I switched to open fermentation for both hopped beer and wash. Nothing looks healthier than a 30gallon hdpe fermenter with yeast floating on top of a vigorous ferment.

[dstaines]

Because of the concentration of linoleic acid that olive oil has along with other sterols. From what Ive gathered olive oil has more than others.

Olive oil is also a lot easier and cheaper for a hobby-brewer and professional brewmasters to get their hands than purified linoleic acid from a chemical supplier.

[Galeoturpis]

I use fish oil (linoleic acid)and sunflower oil (mostly linolenic acid) emulsified with some odor free detergent. The recipe that mycologists use to grow yeast has these essential fatty acids in them (emulsified with tween) so it is probably evidence based. It prevents h2s formation and makes for a stronger cell membrane/wall so the ferment should be more resilient. Olive oil is monounsaturated and might do some additional good to the PUFAs but I don't know.

[shadylane]

If a spoon full of olive oil helps, I wonder what the oil from 50 pounds of cracked corn would do ?

[masonsjax]

Corn oil is chemically created. You can't press corn and get oil out of it. It's also devoid of the lipids that yeast would benefit from. Corn isn't doing anything special for our yeast friends. A drop of olive oil will though.

[3d0g]

Corn oil is chemically created. You can't press corn and get oil out of it. It's also devoid of the lipids that yeast would benefit from. Corn isn't doing anything special for our yeast friends. A drop of olive oil will though.

Huh? So this vid is faked and someone doctored Wikipedia with false lipid counts on the corn oil page?