Using Olive oil instead of Oxygen

[Denny]

Here's an excerpt from Drew Beechum's and my upcoming book "Experimental Homebrewing" based on a conversation I had with Grady Hull.

“This paper reports the findings of a series of full-scale production tests that were conducted in an operating brewery to evaluate the effects of another type of yeast treatment. By mixing olive oil into the yeast, during storage, instead of aerating the wort, fermentations can be achieved with only a minor increase in fermentation time. The beers produced from these fermentations were comparable in flavor and foam retention to beers produced by traditional wort aeration. The ester profile of the beers produced using olive oil addition was significantly higher than the controls and the flavor stability of these beers was significantly improved."
Homebrewers seized on adding olive oil as a way to get around other aeration methods. A liter of cheap olive oil is many times less expensive and lasts longer than the available cans of O2. What most overlook: the technique was used on yeast in storage. It had nothing to do with adding olive oil to the fermenter. Yet folks were adding it to the fermenter and reporting “Well, it didn’t hurt,” or “it seemed to work.” (Remember, there are plenty of homebrewers out there who do no aeration whatsoever and report that their beers are fantastic.)

There was little accounting for the infinitesimally small amount of olive oil needed for a five-gallon batch of homebrew.Reducing Grady’s numbers to our brew lengths brings the dose to less than 0.05 ml of oil per 5-gallon batch. The closest we can get without using lab equipment is to use a drop on the end of a pin or needle. Brewers attempting to use this technique usually also missed out on dissolving the oil in a solution of ethanol first to ensure that it would blend into the wort and not float in the watery wort. We specifically asked Grady about how homebrewers were taking his research and using it in their own ways. Grady replied:
“We never tried using olive oil in propagations. Our tests were centered around using it as a nutrient in yeast storage vessels to eliminate the need for aeration at knockout. Also, we never tried adding the oil to the wort after pitching. The oil was always added to the yeast in the storage vessel and given plenty of time to mix and be absorbed into the cells prior to pitching. We found a slight increase in esters and a slight improvement in shelf life by using olive oil and not aerating. We do not currently use olive oil in our yeast storage vessels. The results did not bear out the shelf life improvements we were hoping for and did not justify installing an olive oil dosing and handling system.”

 

[helibrewer]

Good info Denny, thanks. Looking forward to the book.

 

[Wynne-R]

Yup. That’s the way I do it, a couple of drops in the starter. I just measured it to double check; 20 drops at room temperature weighs .58g. At a specific gravity of .9, two drops is .05 mL.

The original post quoted “someone at New Belgium” who miscalculated it at 0.0000833mL. I think that’s what created most of the confusion.

 

[Denny]

Yup. That’s the way I do it, a couple of drops in the starter. I just measured it to double check; 20 drops at room temperature weighs .58g. At a specific gravity of .9, two drops is .05 mL.

The original post quoted “someone at New Belgium” who miscalculated it at 0.0000833mL. I think that’s what created most of the confusion.

Did you notice he said they didn't use it for propagation?

 

[RM-MN]

Here's an excerpt from Drew Beechum's and my upcoming book "Experimental Homebrewing" based on a conversation I had with Grady Hull.

“This paper reports the findings of a series of full-scale production tests that were conducted in an operating brewery to evaluate the effects of another type of yeast treatment. By mixing olive oil into the yeast, during storage, instead of aerating the wort, fermentations can be achieved with only a minor increase in fermentation time. The beers produced from these fermentations were comparable in flavor and foam retention to beers produced by traditional wort aeration. The ester profile of the beers produced using olive oil addition was significantly higher than the controls and the flavor stability of these beers was significantly improved."
Homebrewers seized on adding olive oil as a way to get around other aeration methods. A liter of cheap olive oil is many times less expensive and lasts longer than the available cans of O2. What most overlook: the technique was used on yeast in storage. It had nothing to do with adding olive oil to the fermenter. Yet folks were adding it to the fermenter and reporting “Well, it didn’t hurt,” or “it seemed to work.” (Remember, there are plenty of homebrewers out there who do no aeration whatsoever and report that their beers are fantastic.)

There was little accounting for the infinitesimally small amount of olive oil needed for a five-gallon batch of homebrew.Reducing Grady’s numbers to our brew lengths brings the dose to less than 0.05 ml of oil per 5-gallon batch. The closest we can get without using lab equipment is to use a drop on the end of a pin or needle. Brewers attempting to use this technique usually also missed out on dissolving the oil in a solution of ethanol first to ensure that it would blend into the wort and not float in the watery wort. We specifically asked Grady about how homebrewers were taking his research and using it in their own ways. Grady replied:
“We never tried using olive oil in propagations. Our tests were centered around using it as a nutrient in yeast storage vessels to eliminate the need for aeration at knockout. Also, we never tried adding the oil to the wort after pitching. The oil was always added to the yeast in the storage vessel and given plenty of time to mix and be absorbed into the cells prior to pitching. We found a slight increase in esters and a slight improvement in shelf life by using olive oil and not aerating. We do not currently use olive oil in our yeast storage vessels. The results did not bear out the shelf life improvements we were hoping for and did not justify installing an olive oil dosing and handling system.”

They were adding olive oil to the yeast instead of aerating the wort. Doesn't that suggest they were using the olive oil for propagation. They just weren't adding it directly to the wort because it was added in with the yeast.

 

[Denny]

They were adding olive oil to the yeast instead of aerating the wort. Doesn't that suggest they were using the olive oil for propagation. They just weren't adding it directly to the wort because it was added in with the yeast.

No, they were using it for storage. You're not looking it propagate yeast when you store it. He specifically said "We never tried using olive oil in propagations".

 

[Wynne-R]

All controls were aerated in-line, with micro filtered compressed air, in excess of
saturation for the entire duration of the transfer according to the breweries standard
operating procedures. The tests were not aerated. For the test fermentations, olive
oil was added to the yeast in storage tanks five hours prior to use and the amount
added increased with each trial.

From the original thesis

I would think “five hours prior to use” is unambiguous. Isn’t five hours about the length of time required to warm up the yeast? Perhaps I should sternly admonish the yeast to avoid propagating.

 

[seabass07]

It sounds like dissolving it in ethanol then adding it to a finished starter and allowing it to sit for ?amount of time before pitching would be similar?

 

[Wynne-R]

I just add it to the starter on the stir plate. Ethanol might work, but it seems like an unnecessary step. The oil will go into an emulsion, and the yeast will ultimately produce alcohol, just in case that’s required. New Belgium probably stored the yeast under beer anyway.

 

[broadbill]

From the original thesis

I would think “five hours prior to use” is unambiguous. Isn’t five hours about the length of time required to warm up the yeast? Perhaps I should sternly admonish the yeast to avoid propagating.

How much cell division would be going on in a yeast starter that had been warmed up after previously fermented out to FG and cooled?

In my mind "propagation" is a very strong word for what would be going on in those olive oil treated cultures.

 

[broadbill]

It sounds like dissolving it in ethanol then adding it to a finished starter and allowing it to sit for ?amount of time before pitching would be similar?

Keep in mind this whole dissolving in ethanol idea was first mentioned by some guy writing a homebrewing blog and to my knowledge has not been attempted.

But then again, this is the olive oil aeration thread so naturally it is high on myth and low on actual results.

 

[seabass07]

Keep in mind this whole dissolving in ethanol idea was first mentioned by some guy writing a homebrewing blog and to my knowledge has not been attempted.

But then again, this is the olive oil aeration thread so naturally it is high on myth and low on actual results.

Denny mentioned it in his excerpt based on his conversation with Grady Hull. I figured that was the method used by NB. Maybe I'm just jumping to conclusions. I was just thinking about how we could adapt the same method they used to our scale. When I make a starter, I generally store it for a couple days before I actually use it. That seems like it would be the time to add the OO based on this info.

 

[Denny]

Denny mentioned it in his excerpt based on his conversation with Grady Hull. I figured that was the method used by NB. Maybe I'm just jumping to conclusions. I was just thinking about how we could adapt the same method they used to our scale. When I make a starter, I generally store it for a couple days before I actually use it. That seems like it would be the time to add the OO based on this info.

But why would you want to? They stopped using it due to the downsides and no appreciable benefits.

 

[seabass07]

I didn't say I was going to, just that it's how they did it. But based on your quote, it sounds like the benefits were noticeable, but didn't warrant a significant investment. There isn't an investment involved on the homebrew scale. I might mess with it a couple times out of curiosity, but I'm not looking to change that area of my process.

Just a thought, but isn't this similar to how dry yeast come packed with enough nutrient for propagation? Aren't they packaged with fatty acids and don't require o2?

 

[broadbill]

Denny mentioned it in his excerpt based on his conversation with Grady Hull.

You are correct that Denny mentioned it in his excerpt, but in reading of Grady Hull's thesis, I did not see this being the case.

Denny...are you sure this method of dissolving OO was used in Grady Hull's thesis work?

 

[Denny]

Denny...are you sure this method of dissolving OO was used in Grady Hull's thesis work?

No, I'm not. That was added by my co-author Drew. Maybe we have the first correction for the website!

 

[Hermit]

oil is not water soluable, so no, the oil will not mix with the wort but when you consider the extremely small quantities required, who cares?

It will spread out on the surface in a thin film. I would think that given the life cycle of yeast it would be pretty much consumed in the first generation prior to budding. I know they scarf up the available oxygen pretty quick if I remember my reading of White correctly,

 

[snowninja1]

I really surprises me that this olive oil idea has as much traction as it does. Grady Hull's thesis is scientifically flawed and inconclusive, the maltose falcon's experiments conclude that there really is no effect of olive oil, other than it only decreases head retention "a little bit", and the best we can get is a bunch of anonymous posters on the web forum that claim it has an effect when they use it.

Can't we put this one to bed? Leave the olive oil for cooking and if you want to oxygenate your wort, use a oxygen setup from your home brew shop.

For me the point is, perhaps with less O2 the beer may have a longer shelf life. Additionally I ran into the problem of being out of 02 yesterday and had remembered this technique. If it works it will have saved my beer. If it doesnt ill post the negative results. It if far cheaper too to use a tiny amount of oo than to use 02.

 

[snowninja1]

I brew 15 batches a year. I go through between 3 and 4 02 cylinders a year. Thats give or take 50 bucks in 02. That said, a batch costs me around 50 bucks when I add gas, hops and malt. I feel like for someone like me its worth the risk if I learn the results are as good. Its just this kind of experimentation that furthers all of our collective knowledge. Just think how far home brewing has come and how good the results can be. This, in my opinion is interesting and exciting. If its not interesting to you then perhaps a different threat is the way to go.

 

[Denny]

I brew 15 batches a year. I go through between 3 and 4 02 cylinders a year. Thats give or take 50 bucks in 02. That said, a batch costs me around 50 bucks when I add gas, hops and malt. I feel like for someone like me its worth the risk if I learn the results are as good. Its just this kind of experimentation that furthers all of our collective knowledge. Just think how far home brewing has come and how good the results can be. This, in my opinion is interesting and exciting. If its not interesting to you then perhaps a different threat is the way to go.

I brew 30-40 batches a year. I use no O2 at all. i simply use a MixStir aerater. I spent $20 on it and I get results equal to when I used an O2 system.

 

[agenthucky]

I brew 30-40 batches a year. I use no O2 at all. i simply use a MixStir aerater. I spent $20 on it and I get results equal to when I used an O2 system.

And there are NHC winners that aerate their batches by shaking them, there is more than one way to skin a cat.

 

[grathan]

I have an 02 tank with wand and still choose to not aerate. I prefer ester production of non-aerated yeast and supplement with Valine to help suppress diacetyl production.

Another neat option is lipids. You could skip vorlauf and dump lipids into the fermenter. Maris Otter is high in lipid content. I don't know how similar this is to olive oil.

 

[user 141939]

I brew 15 batches a year. I go through between 3 and 4 02 cylinders a year. Thats give or take 50 bucks in 02. That said, a batch costs me around 50 bucks when I add gas, hops and malt. I feel like for someone like me its worth the risk if I learn the results are as good. Its just this kind of experimentation that furthers all of our collective knowledge. Just think how far home brewing has come and how good the results can be. This, in my opinion is interesting and exciting. If its not interesting to you then perhaps a different threat is the way to go.

So one tank only lasts you 4 or 5 batches? I just finished my first tank and got i think 12 batches from it, with one minute of aeration. How long do you aerate?

 

[broadbill]

For me the point is, perhaps with less O2 the beer may have a longer shelf life. Additionally I ran into the problem of being out of 02 yesterday and had remembered this technique. If it works it will have saved my beer. If it doesnt ill post the negative results. It if far cheaper too to use a tiny amount of oo than to use 02.

You are the first homebrewer I've come across that is concerned about shelf life, most are concerned about how to keep the supply of homebrew from getting rapidly depleted!

I would argue that you beer would probably turn out just fine had you not done anything at all; but now that the OO is in there you have already concluded it will help (as long as the outcome isn't negative). Now when it does turn out great, you'll attribute it to the OO. This was the bias cooked into Grady Hull's work, and is the bias here as well.

 

[user 141939]

I worry about shelflife with my big beers. I have a tripel that's s year old and becoming oxidized. It'd be nice if it happened a little slower.

It doesn't make much sense that using pure O2 would affect that at all though. Since it's all going to be consumed pretty quick.

 

[Denny]

Did you guys read what Grady wrote? One of the reasons MB doesn't use OO is becasue it decreased the shelf life of their beer. He said it had never been studied for anything other than yeast storage, I have never seen any evidence that it works to replace aeration of wort.

 

[user 141939]

I, sir, have not. I am merely here to chime in at the 11th hour on a subject I know nothing about. Oh, the joys of the internet. 😄

 

[Denny]

I, sir, have not. I am merely here to chime in at the 11th hour on a subject I know nothing about. Oh, the joys of the internet. 😄

Knowing how homebrewers debate this subject, for my book "Experimental Homebrewing", I did something homebrewers apparently hadn't considered doing...I wrote to Grady Hull about his thoughts. You can read the book for the whole thing, but the takeaway is that they didn't get great results with it, don't do it, and never studied it as a replacement for aeration. It's a homebrew myth.

 

[ArcLight]

When you pitch the yeast - If there is Oxygen available , yeast will use it to respire (use Oxygen to produce ATP) while consuming the sugars in the wort, and not produce Alcohol. Once the available Oxygen is gone, yeast will revert to fermentation to produce ATP while consuming the sugars in the wort.
There is no chance Oxygen will be left over, unless some is in the head space, or introduced when racking.


As for how much Oxygen to add when pitching, many home brewers splash the wort/shake the bucket etc with good results. For higher gravity beers you may want to Oxygenate the wort.

 

[LandoLincoln]

My friend and I recently split a 10g batch into two carboys and used two drops of olive oil in lieu of aeration in one carboy and shook the other carboy for 90 seconds to aerate.

Results:

Beginning fermentation took 24 hours longer to start in the olive oil batch (24 hours vs 48 hours).
Krausen to fall took about a week longer in the olive oil batch.
Beer was not as clear in the olive oil batch.
Beer taste was close but not quite as good with the non-olive oil batch.

Conclusion: 90 seconds of shaking is really not that big of a problem.