High gravity, oxygen, and olive oil

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FlyGuy

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Has anyone had any successes (or failures) using New Belgium Brewery's technique of using olive oil instead of oxygen for 'aerating' your beer? I have a good oxygenation system that works well for me, so I am not looking to replace it. But I was thinking that olive oil (OO) might be very useful to add later in the fermentation (say 24 hours after pitching the yeast) of a high gravity brew where it is hard to get enough oxygen (O2) into the wort. Some recommend another round of oxygenation 12-36 hours after pitching, but there is always a danger that adding O2 after fermentation begins will lead to staling in the beer. That would not be a risk with OO. And if OO works as well as O2 like some claim, this might be a perfect solution.

BTW, did anyone notice that OO = 2O, which is very similar to O2???? Hmmm..... coincidence???? :cross:
 
I have read articles on this. The ammount of olive oil for a 5 gallon batch was rediculously small. It was something less than 1 drop per 5 gallons. It might actually be worth an experiment on a cheaper beer first. Then kick it up to a high gravity if it works.
 
There was a thread about this on here about a month ago...try search to dig it out.

I think the math was figured and for small 5 gal batches it would be impossible to get the right quantity of Olive oil based on what they use for their huge batches. I think the conclusion was that we couldn't measure the small amount we'd use...and any more would pretty much ruin the beer...
 
I haven't done any really big beers but on moderate ones 1.070-1.080 I've aerated for the first 24 hrs with sterile filtered air from an aquarium pump. As long as the beer has oxygen in it the yeast reproduce and don't ferment so no risk of oxydizing at that point.

GT
 
I am familiar with the old thread, but nobody has followed up on it. Hence this thread to see if anyone has already experimented.

There have been problems with translating the volumes down from brewery size batches to homebrew batches. The initial math was out by many orders of magnitude. IIRC, the correct amount for a five gallon batch is something like a couple of drops, so it can be measured adequately by homebrewers.

So -- anyone tried it yet? I don't think I am brave enough to do a trial in my IIPA that I am planning.
 
I'm curious about this technique as well. I think that to properly experiment, a 15 gallon batch is in order. Split the batch into three fermenters. In the first fermenter, avoid any aeration whatsoever. Aerate the wort in the second fermenter with your normal method. In the third fermenter, avoid any aeration, then add a single drop of olive oil. Compare fermentation activity and results.

I'd be willing to conduct the experiment, but I can't brew right now due to an upcoming move.
 
That would be a great experiment Yuri. I hope you get the chance to do it after the move. Perhaps I could do something similar at a smaller scale (say half those volumes) when the weather warms and I can get my keggle and burner out of the garage again.

I wish I had a hemocytometer, because it would be easy to do some simple yeast counts with a somewhat similar experiment using yeast starters. I bet you could learn a lot about this method by simply looking at yeast propagation and yeast condition under a microscope.

Does anyone happen to own a microscope and hemocytometer?
 
FlyGuy said:
...There have been problems with translating the volumes down from brewery size batches to homebrew batches. The initial math was out by many orders of magnitude. IIRC, the correct amount for a five gallon batch is something like a couple of drops, so it can be measured adequately by homebrewers...

I'm sure one of the brewing podcasts tried it.

IIRC, they boiled a known amount of OO in a known amount of water to dilute it to the right concentration for their batch - I assume this was with the original initial amount of OO though.
 
I have found another use for the EVOO (just had to say that here) instead of O2: when I propagate yeast from single cells, I cannot afford oxygenating the first few steps since I don't trust the O2 system to be steril. I'm alredy pressure-canning small amounts of wort in vials and baby food jars for this purpose. Now I'll be adding very small amounts of OO as well to make sure the yeast will grow well w/o having to add O2. So far it has worked w/o the OO or oxygen in the first 2 stages, but I'll see how much better it works with the OO.

Kai
 
Okay, being a fan of biochemical pathways I did a little more reading. There is similar thread going on the NB site, but I thought I'd post here.

My understanding is that the current hot topic says that by providing the yeast with an unsaturated fatty acid, they don't need O2 to grow. In my searching, well yes and no. The first question to myself was why does the yeast need an unsaturated fatty acid. We burn fats for energy, also sugars. Sugars are easier. We've provided the yeast with plenty of food in the form of sugars, so burning fats for energy is probably a minor function in yeast. ....more searching, then...... Oxygen is required for the oxidation of fatty acids which does provide a little energy, but more importantly for the yeast it provides acetyl CoA which it then uses to produce ergosterol - a VERY important component of the cell membrane (up to 2% of all the cell components). So by adding some unsaturated fatty acid, you can reduce the amount of O2 required to make ergosterol.

But wait! Ergosterol is required for anaerobic growth of yeast. Why? Well, it is an integral part of the cell membrane so to get more yeast you need to make more membranes. It turns out that the last 2 of the 20+ enzymatic steps to go from Acetyl CoA to ergosterol both require O2. This to me indicates that even with OO, you would still need some oxygen. So what you might really want to add is ergosterol, not OO. Where can one get ergosterol? This is one thing I'm mulling right now. One obvious source is dead yeast (up to 2% ergosterol by weight). I wonder if you could just add some dead yeast when you boil up your starter (or boil some starter with live yeast, making them dead yeast). Ergosterol is not very water soluble, but then again, neither is OO. I haven't yet found a commericial source. Tempe (fermented bean curd) is loaded with it.

Starters only or fermentors too?
The second thing I'm wondering is just how much if any, yeast growth do you want to occur in the fermentor, as opposed to the starter. If you add too much OO or ergosterol (not worrying about head retention at this point), and it carries over into the fermentor will you get too much growth - as if you over-pitched. It is my understanding that when yeast are actively dividing, they aren't making much alcohol, and once the O2 has been depleted they switch to fermenatation and begin to make ethanol. If this is indeed the case, if one wanted optimal alcohol production,it would make sense to add all of the yeast you would need right at the beginning. By adding OO or ergosterol to the fermentor would you end up with more yeast but less alcohol? This could be an interesting way to get a lot of flavor in a lower alcohol beer.

This however would suggest that open fermentation would give you less alcohol as the O2 can be replaced as it is used up. Although maybe it is consumed by the yeast so fast because there are so many of the little buggers, that for most of the yeast they may be O2 deprived. Does anybody have any insight on this?
 
As I said in the old thread, I tried it and I don't recommend it. It may be better on larger scales, but not for most homebrewers...
 
pjj2ba said:
Okay, being a fan of biochemical pathways I did a little more reading. There is similar thread going on the NB site, but I thought I'd post here.

maybe I should check that out as well.

but more importantly for the yeast it provides acetyl CoA which it then uses to produce ergosterol ........It turns out that the last 2 of the 20+ enzymatic steps to go from Acetyl CoA to ergosterol both require O2. This to me indicates that even with OO, you would still need some oxygen.

When I read Acetyl CoA I think esters. When Acetyl CoA is not consumed by yeast growth it is used for the production of esters. That's why impeding yeast growth generally leads to higher esters. Now when we add OO we allow the yeast to make Acetyl CoA, but then we don't give it the O2 to make the sterol needed for growth. Hence an overproduction of Acetyl CoA and more esters. I did remember that they mentioned that the OO beer had more esters and I would expect that adding to much OO will create an ester ladden beer.

The second thing I'm wondering is just how much if any, yeast growth do you want to occur in the fermentor, as opposed to the starter.

This has been discussed before. You want some yeast growth in the beer since it produces byprpducts that are, to a certain level, desired. Even in lagers you want some esters, just less than you would expect in an Ale or Weissbier.

This however would suggest that open fermentation would give you less alcohol as the O2 can be replaced as it is used up. Although maybe it is consumed by the yeast so fast because there are so many of the little buggers, that for most of the yeast they may be O2 deprived. Does anybody have any insight on this?

There is not much O2 uptake in open fermentation since you have a constant stream of escaping O2.

Also, there is continued yeast growth during fermentation. Since no sterol is produced anymore the yeast has to live of its reserves which are shared between mother and daughter cell when they split. Eventually they run out and growth will stop.

Kai
 
I don't know the answer to whether Olive Oil is actually as helpful as we think to the yeast but I do think it's possible to replicate the experiment.

If I remember right it was 300ml of OO to a 4500 L of yeast. Now I don't know what they mean by 4500 L of yeast, slurry? starter? For my purposes I'm going to go with starter, meaning we need to scale down by 4500 (to get the usual size, 1L starter) If they mean slurry then we'd be over OOing but I don't know if that would really affect the beer in such a large dilution (when you pitch the starter into 5 gallons).

So being that 1 ml = 20 drops (or thereabout) you could add between 1 and 2 drops of OO and be somewhere in the same range as the professionals were.

I also am looking forward to Yuri or someone actually doing this experiment (Hopefully on a light ale so that differences are not too masked by other flavors)
 
conpewter said:
I don't know the answer to whether Olive Oil is actually as helpful as we think to the yeast but I do think it's possible to replicate the experiment.

If I remember right it was 300ml of OO to a 4500 L of yeast. Now I don't know what they mean by 4500 L of yeast, slurry? starter? For my purposes I'm going to go with starter, meaning we need to scale down by 4500 (to get the usual size, 1L starter) If they mean slurry then we'd be over OOing but I don't know if that would really affect the beer in such a large dilution (when you pitch the starter into 5 gallons).

So being that 1 ml = 20 drops (or thereabout) you could add between 1 and 2 drops of OO and be somewhere in the same range as the professionals were.

I also am looking forward to Yuri or someone actually doing this experiment (Hopefully on a light ale so that differences are not too masked by other flavors)


It is ~20µL olive oil for a 300mL yeast slurry by the correct back-calculation, figuring homebrewers would be pitching about that much of a slurry. I covered the details in the original thread.
 
pjj2ba said:
Where can one get ergosterol? This is one thing I'm mulling right now. One obvious source is dead yeast (up to 2% ergosterol by weight). I wonder if you could just add some dead yeast when you boil up your starter (or boil some starter with live yeast, making them dead yeast).

I've been under the impression that the "yeast nutrient" that comes with many "yeast starter kits" is composed of dead yeast cells.
 
BlendieOfIndie said:
I've been under the impression that the "yeast nutrient" that comes with many "yeast starter kits" is composed of dead yeast cells.

That's correct. Plus usually some free-amino nitrogen component, amino acids, and chelated zinc.
 
I tried this on an extract I made Friday

Blonde Ale, OG 1.043, very small amount of olive oil, rehdryated Safale S-05

I woke up this morning and it had blow off .. I've never had a medium gravity, dry yeast beer blow off before. I'll wait and see how it ends up but so far so good.

I'll take adding a tiny drop of olive oil to a set of 02 aeration equipment any day of the week :D

EDIT: 5.5 gallon batch.. the amount of olive oil was the very scientific method of dipping the sanitized tip of my metal meat thermometer into some olive oil and swishing it in the liquor I used to top up the volume in the carboy
 
Hopleaf said:
I tried this on an extract I made Friday

Blonde Ale, OG 1.043, very small amount of olive oil, rehdryated Safale S-05

I woke up this morning and it had blow off .. I've never had a medium gravity, dry yeast beer blow off before. I'll wait and see how it ends up but so far so good.

I'll take adding a tiny drop of olive oil to a set of 02 aeration equipment any day of the week :D


would like to more about he batch size and amount of Olive oil used

swmbo is not strong enough to shake a 5 gal batch in a glass carboy

thank you
 
I tried this two days ago on a RIS I brewed. Didn't oxidize it at all, siphoned it from the pot to the carboy. It's currently got krausen almost to the top of a 6.5gal fermentor. Have a blow off attached just in case. I'll know how the beer is in xx months....
 
I tried this two days ago on a RIS I brewed. Didn't oxidize it at all, siphoned it from the pot to the carboy. It's currently got krausen almost to the top of a 6.5gal fermentor. Have a blow off attached just in case. I'll know how the beer is in xx months....

So, how did it turn out? How long did fermentation take?
 
Have a look at the results of a blind triangle test done here.
Go to the top topic, click and go to the post concerning oo vs o2
http://hbd.org/cgi-bin/discus/discus.cgi


Interesting read, but as some others correctly pointed out in that thread, there was no negative control (i.e. no aeration method) to compare to.

I think Kaiser's experimental design where one batch would be split 3 ways for 3 treatments (no aeration, O2, and OO) would be very telling. It might also demonstrate that there is no effect of aeration at all, as some people around these parts believe (I do recall reading about them in the past).

I think its great that folks like rurounikitsune and hopleaf are trying OO in their brews and finding success with it, but I would urge caution in concluding that OO does improve aeration and brew quality just because it works for them. My point is just that without the proper controls its sometimes difficult to find out what is the actual cause of their spectacular brews.
 
forgive the comment on an old topic.
I am intrigued by the OO as yeast supplement.
I would consider adding OO as a yeast supplement to a 1 liter starter for a 5 gallon batch. I've read trough the original paper submitted by the New belgium brewer, and it seems he had better tasting beer every time he increased the OO addition in his starter. I am disappointed that he did not continued adding OO until he tasted off flavors in the finished product, as that would have given us an upper range for addition.
slanting and washing yeast ( along with drinking) is one of the fun things about brewing my own. I may be a hapless noobie, but I'm surprised that there isn't more reports/testing on this process to determine the effect and limits of the OO addition.
FWIW i'm going to give this a try with 10x (probably one drop) in a 1 liter starter .
 
It is ~20µL olive oil for a 300mL yeast slurry by the correct back-calculation, figuring homebrewers would be pitching about that much of a slurry. I covered the details in the original thread.

I calculated for 1L of yeast slurry, so numbers are off of mine (60µL) which is about a US drop that I mentioned. Even if you only pitch 300ml of yeast slurry it is not going to hurt 5 gallons of beer to have an extra 40µL of olive oil.

(Yes I know zombie thread)

FWIW i'm going to give this a try with 10x (probably one drop) in a 1 liter starter .

Will be eager to hear your results. I do think it would be good for starters as it can be a more sterile method. And good to add to big beers that may need the extra help after the initial oxygenation is used up.
 
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