# Wort Aeration



## jonocarroll (14/2/09)

I was up in Clare last weekend (the town, dirty buggers ) at a few (very) lovely wineries with the Wine Guild, and got to asking a few questions about yeast. It doesn't seem to get much of a mention on the tours (and these are tours with people who know their stuff) so I asked. Apparently it _is_ talked about a lot between winemakers. 

I asked what types of yeasts the the wineries used and how they inoculate their must. Wild ferments are not so common any more, but a few places still do open ferments and use the local wild strains. For closed ferments, a neutral yeast is typically used (esp. in whites). I inquired about these yeasts and one winemaker told me they use 500g in 1000L of must - aerated with a nitrogen-oxygen mix. Essentially a giant starter. Once this has completed the aerobic phase, it is pitched to the main batch to ferment out.

I asked what they do to aerate the entire batch - they don't.

I don't know what the bigger breweries do. Perhaps someone on here does. Anyhoo - the point of this story (_I like stories_) is a question - if we make large enough starters, do we really need to aerate the wort at all? I know yeast need to acclimatise to their surroundings, but can they do that in the anaerobic phase, or do they really need to reproduce further? I've seen the comparisons regarding shaking vs. direct O2 injection, and the results was that it really didn't matter which you did, or even that shaking was better. Can't recall if that used a starter or not.

If it's a dumb question, just let me know. Otherwise, I'm keen to know if anyone has any knowledge or experience with this. Remember, it's pedantic little me here, so starting a reply with 'I don't know anything about it, but this is exactly what happens' won't get you any brownie points <_<


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## alexbrand (14/2/09)

Hi QuantumBrewer!

Right after pitching the yeast needs the oxygen to grow (not the single cell, but the amount of cells). So if you pitch lots of yeast into your non areated wort it will do the job because there's already enough yeast. If you don't have enough yeast ready to pitch you have to areate (or use olive oil instead) for increasing the number of cells.

This is what you winemaker did. I guess, oxygen is not wanted in the fresh grape juice for some "taste" reason.

Cheers,

Alex


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## jonocarroll (14/2/09)

Hmm... Perhaps I didn't make clear enough the level of answer I'm after - I get the aerobic reproduction phase. I understand the role of oxygen here. I'm curious to know whether or not people who make a starter still do something to aerate their wort, or if they just pitch a sufficient starter and begin the anaerobic phase.

The reason the winemaker doesn't aerate the entire batch is because he feels the starter is large enough, and the yeast can go straight into anaerobic fermentation. Oxygen in wine fermentation is an easy hurdle - they just throw SO2 at it until it isn't a problem anymore. Wine is racked often enough, and sits around in barrels for long enough, that the SO2 comes out of solution, just like lagering.


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## hockadays (14/2/09)

Was reading about this today on the wyeast website and they say to pitch a starter with the appropriate amount of yeast and then to get the dissolved O2 up to 10ppm. Their preference was to use pure O2 injection as airstone/splashing etc could only get a max of 8ppm. So to your question I think you need both.


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## alexbrand (14/2/09)

Well, the bigger the starter is the less you need to areate the wort. If you have 'big enough starter' there's no need anymore to areate the wort prior to pitching.

Isn't that what you're after?

Cheers,

Alex


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## hockadays (14/2/09)

If you pitch too big a starter though you run into problems from overpitching and thence poor attenuation. Check the wyeast site on yeast and o2 as it explains it pretty well.


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## kirem (14/2/09)

QuantumBrewer said:


> The reason the winemaker doesn't aerate the entire batch is because he feels the starter is large enough, and the yeast can go straight into anaerobic fermentation.
> 
> Oxygen in wine fermentation is an easy hurdle - they just throw SO2 at it until it isn't a problem anymore. Wine is racked often enough, and sits around in barrels for long enough, that the SO2 comes out of solution, just like lagering.



The first part is the way we do it. get a 10^8 cell count in the yeast culture then innoculate. We turn approx 80000t of grapes into wine and don't get stuck, sluggish or non-typical fermentations, it would get very expensive, very quickly if we did. It is also the way I make beer, I don't aerate my wort, I aerate my starters and get the correct cell count and then add the correct volume of starter to my wort. I suppose it is the winemaker coming out in me, but I feel that aerating the wort will oxidise aroma and flavour molecules. Perhaps a brewer can explain to me why this wouldn't happen in wort like it does in grape juice. 

The second part is wrong. I don't know any winemaker male or female  that adds SO2 to a fermentation. It does have a role pre fermentation, but very limited.
SO2 does not come out of solution. you have molecular SO2 (a fraction of the FSO2 and is pH dependent), Free So2 and total SO2. FSO2 is SO2 that is not bound (ie free to scavenge oxygen) and Total SO2 is a combiantion of Free SO2 and bound SO2(already done its job scavenging oxygen). Molecular SO2 is the bomb, it is the antimicrobial form.

We also use ascorbic acid to prevent oxidation in white wine, although you need SO2 to work with it.

I think in your lagering comparison, you are confusing H2S and SO2

Oxygen and SO2 in winemaking can be very simple or extremely complex, depends how far you want to take it. Introduce redox potentials, tannins etc and it gets very complex. Oxygen can be a very good thing in winemaking (especially reds) but it has to be controlled and you have to know exactly what you are doing and trying to achieve.

You mentioned barrels, barrels basically have two functions oak flavour and slow introduction of oxygen into wine, micro oxygen imitates this function in tanks.

these attachments explain it.
View attachment 24727

View attachment 24728


I posted a bit about so-called wild ferments in this thread - http://www.aussiehomebrewer.com/forum/inde...st&p=413784


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## kirem (14/2/09)

http://www.danstaryeast.com/library/aeration_vs_wort.html

AERATION AND STARTER VERSUS WORT

Can you please comment on the strategy of trying to aerate/oxygenate the yeast while they are in a STARTER rather than aerating the wort itself. (Please let me abuse the language and science a bit and just say that yeast need "a big swallow of oxygen" before they ferment beer.)

I understand that this is exactly your strategy in the production of dry yeast--i.e. dry yeast can be pitched into unaerated wort because they have already taken their big swallow of oxygen. How feasible is it for a homebrewer to grow up a starter in similar fashion? Is continuous aeration of the starter required? A stir plate?

If I have no stir plate, and no gas transfer equipment of any kind, is there a practical procedure I can follow to grow yeast whose oxygen requirements are already met? Letting air into the starter jug and shaking it, repeating this over several days, etc? Any temperature dependency? Any minerals or nutrients I can add to the starter to increase the yeast's efficiency at storing up oxygen-related compounds? Thank you for sharing your expertise.

- Matt


RESPONSES:

Yeast need a trace amount of oxygen in an anaerobic fermentation such as brewing to produce lipids in the cell wall. With out O2 the cell cannot metabolize the squalene to the next step which is a lipid. The lipids make the cell wall elastic and fluid. This allows the mother cell to produce babies, buds, in the early part of the fermentation and keeps the cell wall fluid as the alcohol level increases. With out lipids the cell wall becomes leathery and prevents bud from being formed at the beginning of the fermentation and slows down the sugar from transporting into the cell and prevents the alcohol from transporting out of the cell near the end of the fermentation. The alcohol level builds up inside the cell and becomes toxic then deadly.

Lallemand packs the maximum amount of lipids into the cell wall that is possible during the aerobic production of the yeast at the factory. When you inoculate this yeast into a starter or into the mash, the yeast can double about three time before it runs out of lipids and the growth will stop. There is about 5% lipids in the dry yeast.

In a very general view:

At each doubling it will split the lipids with out making more lipids (no O2). The first split leaves 2.5% for each daughter cell. The second split leaves 1.25% for each daughter cell. The next split leaves 0.63%. This is the low level that stops yeast multiplication. Unless you add O2 the reproduction will stop.

When you produce 3-5% alcohol beer this is no problem. It is when you produce higher alcohol beer or inoculate at a lower rate, that you need to add O2 to produce more yeast and for alcohol tolerance near the end of fermentation. You definitely need added O2 when you reuse the yeast for the next inoculum.

If you prepare a starter culture you will need added O2. in the starter and perhaps in the main mash as a precaution. You will need to follow the precautions as mentioned above. If the mash is designed to produce 3-5% alcohol you may not need added O2. Brewing above that needs added O2.

Regarding your comment about growing your own yeast that will not need added O2 in the fermenter; The Lallemand yeast factory grows yeast under a different metabolic pathway than you will have in your starter culture. We feed the media to the aerobic fermentation at a rate that will keep the sugar levels below 0.2% at all times to maintain the Pasteur Effect. This builds cell mass with minimum to no alcohol production. As the sugar level rises above 0.2% the Crabtree Effect begins and no matter how much air you feed the fermentation, alcohol + CO2 are the main by-products. Your starter culture will have a much higher level of sugar. You will produce some cell mass but mostly alcohol and CO2 no matter how much air you add by stirrer or bubbles.

Dr. Clayton Cone


As Clayton mentioned oxygen is absolutely necessary to produce biomass. So I would aerate your starter as much as possible (stirrer or an aeration system used in fish tanks.)As nutrients I would add a product like FermaidK or GoFerm who add extra nitrogen, minerals and vitamins which are necessary for biomass production. These nutrients also contain some precursors that are needed for lipid production. The best temperature to build a starter is 20-28 degree Celsius. The higher the temperature the faster you build biomass. If you use higher temperatures (28 C) I would recommend separate the yeast from the media as much as possible (decanting) because at this high temperature you build up a lot of higher alcohols and esters which you don't want in your beer.

If you want to pitch your yeast without aerating the wort you need to prep your yeast in the starter for that. Aerate well so that the yeast can build enough unsaturated fatty acids. There are commercial breweries who aerate the yeast before pitching and not the wort. They believe they can increase the flavor stability of their beer this way.

Tobias


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## kirem (14/2/09)

and this one. http://www.fermentarium.com/content/view/254/58/
Should you put olive oil in your homebrew? E-mail
Written by DJ Spiess 
Monday, 29 September 2008


There are many things you can add to your homebrew, but the most interesting addition might be olive oil. It sounds crazy, but does it make any sense?
Why use olive oil in your homebrew?
Your yeast need oxygen for a happy and healthy fermentation. Yeast use oxygen during the lag phase to synthesize sterols and unsaturated fatty acids for its cell walls. If there is not enough oxygen, the yeast can not grow and die off early. Low oxygen leads to stalled fermentations and off-flavors. This is the reason you need to shake the carboy before pitching your yeast.



The problem is with too much oxygen your wort can become oxidized. An oxidized beer will taste like cardboard ass (or sherry but not in a good way). Any time you add oxygen to your beer, you run the risk of some oxidation. The olive oil solution is an attempt to avoid oxidation.

So why would you add olive oil? The idea behind olive oil is instead of giving the yeast oxygen to manufacture the unsaturated fatty acids, give the yeast an unsaturated fatty acid. Your wort doesnt get oxidized and your yeast get what they need for their growth.

* Oxygen is used by yeast to synthesize sterols and unsaturated fatty acids for its cell walls
* Ale yeasts need about 5 parts oxygen per million in wort, while lagers can need 10 to 12 parts oxygen per million.
* Olive oil gives yeast the compounds synthesized for cell wall construction


Where did this crazy idea come from?
Adding unsaturated fatty acids like linoleic acid to wort was attempted in several studies, but in 2005 Grady Hull, with the help of New Belgium Brewery, decided to try using olive oil. Olive oil was chosen because it is much more readily available and olive oil contains the same unsaturated fatty acid beer yeast produce. Linoleic acid is not naturally produced by yeast. It would seem olive oil was the perfect choice.

* The olive oil experiment was in a 2005 thesis by Grady Hull
* The experiment was conducted at New Belgium Brewery in Fort Collins, Colorado 


With the help of New Belgium, brewers tested adding olive oil to beer.
With the help of New Belgium, brewers tested adding olive oil to beer.


How well did it work?
The experiment worked quite well for Grady Hulls goals. The original goal was to compare the effects of adding olive oil to storage yeast vs. traditional wort aeration. They found they could achieve similar results in the final product using olive oil. The paper did note ester production was higher than the traditional aeration beer, but the additional esters were within production limits; in fact the flavor panel at New Belgium preferred the higher ester flavored beer. They also found the fermentation times were slower.

The New Belgian Brewery was also looking to increase shelf life for their beers. Less oxygen means they can keep their beers on the shelf longer. Hull reported increased flavor stability in the olive oil beer. Based on the goals set out by Hull, the experiment seemed to hit a home run for macro breweries, but the question everyone wanted to know still remains. How well would olive oil work on my homebrew? No one really knows yet.

* The olive oil beer produced more esters and took longer to ferment - both were still within accepted norms 


How much olive oil do I use in my homebrew?
In the study, Hull added olive oil based on the total number of cells. He didnt list actual volumes in the paper because there can be variations in yeast slurry thickness. In the first trial they added 1 mg of olive oil per 67 billion cells pitched into 360 hl of wort, and the final trial they added 1 mg per 25 billion cells pitched into 2100 hl of wort.

So how much olive oil is this on a homebrew scale? Going by their numbers you would need about 0.036 ml for a 5 gallon batch. In short, less than a drop. Probably not even that much. Most brewers adding olive oil in their homebrew are sticking a pin tip into olive oil and rinsing it into their wort. Even this small amount is likely too much if the numbers are correct.

Is this the secret ingredient for your next beer?
Is this the secret ingredient for your next beer?


The study's authors added their olive oil to the yeast slurry about 5 hours before use. To do this at home, you need to add the olive oil to your yeast starter.

* Use the tip of a pin to get a small drop of olive oil
* Add the olive oil to your starter


Questions left unanswered
The first question I had after reading the thesis is: would this work for lagers? The study reported higher esters in each of their trials, but since they were making Belgian ale the esters were desired. In the case of a lager, you do not want increased ester production. This technique would be good for big beers or ales where esters are expected, but I have to question how well it will work in lagers.

Many homebrewers in brewing forums using this method and claim wild fermentations, wonderful beers, etc but unfortunately this is anecdotal evidence. The study at New Belgian Brewery claimed their olive oil fermentations actually took 20% longer than normal fermentations. If this is accurate, your fermentation at home should be slower not faster. It would be interesting to devise an experiment to try at home to see how well this scales to homebrew breweries. If youve tried this before, let me know how well it worked for you in the comments below.

* Interesting idea, but it needs more experimentation for home use
* Increased esters might be bad for a lager


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## hoohaaman (14/2/09)

I have given up on wort aeration,I instead spend my time on cell count and health in the starters .After the extra drama and extra chance of contamination associated with wort aeration,I have found no difference in either attenuation or taste.

There was a article mentioned in a thread in the last 8 weeks, regarding tests done on none aeration of wort and o2 uptake of yeast for healthy fermentation.Interesting read.

I know this is not accepted practice,but works for me.However I always pitch well aerated large starters

Info posted above while procrastinating


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## jonocarroll (14/2/09)

Yes, I meant H2S. My bad on that one. I don't make wine myself, but I'm part of a 'Winemakers & Brewers Club' so I hear a lot of talk. As for oxidation when aerating wort... that's part of the motivation behind my question. Seems like aerating the starter is the way to go then pitching that at high krausen (or whenever one prefers), perhaps without the oxidised 'beer' on top, to let the anaerobic ferment go ahead strong.

On a slight side note - to the people who use a stir-plate with their starters; the reason for stirring is to keep the yeast in suspension and to continually introduce O2 while allowing CO2 to escape, yes? If the starter is sealed, how does more O2 get in? Not saying it doesn't, just asking.

Edit: Just saw your second reply... *Now that's an answer!* Noice. Cheers & Beers!

Edit: Just saw your third reply. You know that all my future questions are coming your way from now on, right? I have heard of that method, but not the paper. I'm not sure I'm willing to be the guinea pig brewer, but it sounds like it's worth a go. I'll stick with aerating a starter for now. Cheers!!!


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## THE DRUNK ARAB (14/2/09)

kirem said:


> and this one. http://www.fermentarium.com/content/view/254/58/
> Should you put olive oil in your homebrew? E-mail
> Written by DJ Spiess
> Monday, 29 September 2008
> ...



That was a great read Kirk, thanks!  

C&B
TDA


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## kirem (14/2/09)

QuantumBrewer said:


> I don't make wine myself, but I'm part of a 'Winemakers & Brewers Club' so I hear a lot of talk.



good old ANAWBS?

I also hear a lot of talk. I suppose everyone has their own way of doing things and if it works for them and they get the desired result then great. I would be interested to hear from thirsty_boy or DiG on this and the reason why aerating wort doesn't oxidise the same way as it does in grape juice.


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## jonocarroll (14/2/09)

kirem said:


> good old ANAWBS?


Nope.

Close, but not quite. Actually not close at all, just containing a lot of entrants, judges, stewards, and a RussTaylor.


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## buttersd70 (14/2/09)

QB
You thought some of my answers were long. :lol: 
But understandable when you think of the complexity of yeast......Brewing Science and Practice, for example, dedicates 3 out of 23 chapters, just to yeast...Chapter 12, particularly 12.6-12.7 (and its subsequent subchapters) contain your answer in a bit more detail, which kirem has summarised very nicely indeed, from alternative sources.


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## jonocarroll (14/2/09)

buttersd70 said:


> QB
> You thought some of my answers were long. :lol:
> But understandable when you think of the complexity of yeast......Brewing Science and Practice, for example, dedicates 3 out of 23 chapters, just to yeast...Chapter 12, particularly 12.6-12.7 (and its subsequent subchapters) contain your answer in a bit more detail, which kirem has summarised very nicely indeed, from alternative sources.


If I so much as open that book, it will be the end of me for weeks :nerdyicon:

One day we're all going to have to find out the rest of this 'scumbag' story from your sig. One day.


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## hoppinmad (15/2/09)

To let you know of my history... I am actually a Winemaker and coincidently did one year at Jim Barry Wines (Clare Valley) in 2002. Now to answer your question about aeration of "must"... the answer is that it is not neccessary. Modern wine yeast is manafactured under highly aerobic conditions and when freeze dried have a very large concentration of O2 inside and between the individual yeast cells. Obviously it is important to get a good starter going to adapt them to the temperature and pH of the juice, but this is not oxygen related at all. The usual rate used is between 250-300mg/L

As far as wild yeast goes, well you'll find that once a winery has been using cultured yeasts for a while, it is all over the cealings, floors, walls etc.... and any uninoculated ferments are not really "wild yeasts"... just cultured yeasts that find there way into a vat of juice without being invited.

I'm not sure exactly how beer yeast is made... so to be on the safe side I do splash my wort around a bit. But as far as wine is concerned... introducing oxygen is not necessary with our yeast strains


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## Thirsty Boy (15/2/09)

Actually, no one has mentioned (unless I missed it) the main reason why winemakers don't aerate the must while brewers _do_ aerate the wort - 

*boiling*

must isn't boiled and wort is - which drives out all the dissolved oxygen. Must has a lot more oxygen than wort in the first place. O2 does oxidize compounds in wort as it does in must.... its just that there is a lot less of it and its only "put" there just prior to inoculation when it will be fairly quickly taken up by the yeast.

you only need 3-5 generations of growth to give the appropriate flavour profile in beer ... a dried yeast has enough internal juice for about 3-4 generations of growth, so thats why the above quoted article says that with a lower ABV beer, you dont need aeration... less growth required for the cell count needed in a low abv beer. More in a high abv beer and you will require extra 02

I have no idea of the DO levels of a wine must... but it has to be more than the virtually zero in a post boil wort, that extra DO may well be the difference between the needed growth for a wine yeast and the actual pitching rates. From crush to pitch however.. I suspect the DO levels in a must are high vs wort and there would be a much higher level of oxidation (given the time) in a must vs a wort that spends 1 hr max between oxygenation and yeast pitching. Guesses only....

My take on it is (and I readily stand to be corrected by actual wine makers AND brewers like kirem and HoppinMad) is that the pitching rates in wine are lower than in beer, because the yeast characteristics play a much bigger part in wine flavour profiles that they do in beer. In beer, yeast characteristics are _important_... but in most styles it is a very subtle difference between the yeast being an important sub character to the malt and hops, and it dominating unpleasantly. Winemakers do a LOT more with their fermentation control than brewers do to manipulate things beyond just pitching rates. If it was just pitching rates and strain characteristics... I could be a wine maker, and I know bloody well that I couldn't.

Brewers on the other hand need to grow their yeast in a medium that is essentially oxygen depleted -- and the healthiest yeast you can get... has 3-4 generations of growth in it before it needs external oxygen. Do your research - if you are fairly sure that you need 3 generations or less of yeast growth in your beer, you don't need 02. If you are brewing a bigger that 3% abv....... well maybe you do.

There is also the fact that brewer re-pitch - and under oxygenation is a MUCH bigger issue if you are re-using your yeast. It's still very important for single generation brewers, but vital for re-pitchers.

I admit, most of my assurance that oxygen addition is vital to beer making, comes from commercial practice. Perhaps if you use dry yeast and are making a low abv beer you don't need it - perhaps if you use olive oil in the starter (a promising experimental technique) you don't need it - but in a more than 3% av beer, in which you would like to pitch a beer where your number of generations of growth will give you a "normal"sort of flavour profile for the beer you are making---- the standard technique of oxygenating your wort is probably your best bet.

There are a shit load of subtleties - and I truly think that beer makers have a lot to learn about yeast from winemakers. But that stuff is at the experimental edge ... way beyond my knowledge. If you are looking to make a more "standard" beer, and standard beer is what I know: then get some oxygen into your wort. Its a playing for the center of the fairway thing ---O2 _will not_ hurt your beer and will probably help it - lack of 02 _might _not hurt your beer and might well actually hurt it.

If I were betting a $100 on the outcome.. I know which horse I would choose

I'm simply making some of the case for oxygenation of wort here - I don't pretend that I am 100% right, and I certainly don't pretend more yeast knowhow than the winemakers. But there are reasons why the brewing tradition adds oxygen to wort and wine tradition doesn't - those reasons are very challengeable, but its going to have to be a pretty solid challenge.

TB

over to dig for properly educated answer....


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## newguy (15/2/09)

QuantumBrewer said:


> Hmm... Perhaps I didn't make clear enough the level of answer I'm after - I get the aerobic reproduction phase. I understand the role of oxygen here. I'm curious to know whether or not people who make a starter still do something to aerate their wort, or if they just pitch a sufficient starter and begin the anaerobic phase.



I give my wort a shot of pure O2; 30 seconds for the first pitch from a starter and 0-15 seconds if repitching onto a yeast cake (depends on the beer) - very high gravity brews usually get more. I've always built up pretty large starters but only relatively recently have I started using O2. I started using O2 because I was getting stuck fermentations even though my lag times after pitching were reasonable (6 - 12 hours). For me, O2 was introduced as a fix to a problem I was consistently having, not because the homebrewing literature said I needed it or because I was worried I was underpitching. Even though I have no way to confirm/count the number of active cells I pitch, I'm pretty sure it's in the proper ballpark.


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## kirem (15/2/09)

Thirsty Boy said:


> Actually, no one has mentioned (unless I missed it) the main reason why winemakers don't aerate the must while brewers _do_ aerate the wort -
> 
> *boiling*
> 
> must isn't boiled and wort is - which drives out all the dissolved oxygen. Must has a lot more oxygen than wort in the first place. O2 does oxidize compounds in wort as it does in must.... its just that there is a lot less of it and its only "put" there just prior to inoculation when it will be fairly quickly taken up by the yeast.



Doh. Bloody obvious. :lol: I'll get a DO on some red coming in today and some white tomorrow. We do put SO2 in the picking bins of most varieties, so that will reduce the DO and we will see to what level.


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## neonmeate (15/2/09)

very interesting thread! i'm really interested in wild ferment wines - the ones ive had are not nearly as off the wall as cantillon or anything - but i like the idea of finding one. can any of you winemakers recommend some really rough and funky wild fermented wines?

re the aeration side of things. there was a big discussion about this exact topic all over HB forums 5 years back - and this dude from UC Davis caused a stir when he recommended exactly what QuantumBrewer is proposing - get your yeast count up with lots of air in very healthy starters, then DONT aerate in the wort.

http://www.beertools.com/html/articles.php?view=245

http://www.beertools.com/html/articles.php?view=251

"Wort Aeration:

If possible, don't! The reason is that it is not the wort that needs the oxygen, it is the yeast. By oxgenating the wort instead of the yeast starter, it will cause an over production of cells due to the excessive oxygen presence. This then leads to the production of unwanted esters and higher alcohols that will compromise beer flavor.

When oxygenating starters, you cannot use pure O2... the reason is that the uptake occurs too fast and without a dissolved O2 meter ($$$), you cannot tell when to stop. The way to properly do this one is to aerate using a high pressure aquarium pump, sterile air filter and a stainless steel aeration stone, all of which are redily available. It is virtually impossible to over-aerate using air, so you will avoid oxygen toxicity problems that will occur if trying to do this with pure oxygen."


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## kirem (15/2/09)

Yalumba make some interesting wines, I think they have a 'wild ferment' chardonnay. Yalumba are a very trustworthy company and I think they wouldn't just put wild ferment on the label for something that started fermenting naturally in the winery. I would suspect that they put some effort into making it a true wild ferment.


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## Darren (15/2/09)

I have never airated my wort and never had a stuck ferment ( I airate my starters by shaking when I use them). I fail to see how cooled wort is O2 free. There is always a little bit of splashing when I transfer from my kettle. Only way I can imagine O2 free wort is if one was to "no-chill" then ferment in the same cube.

EDIT: Wine must would also be 2-3 times the OG of most beers, but the yeast manages without airation. Airation on the HB scale, BOLLOCKS

cheers

Darren


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## kirem (15/2/09)

I will see if I can borrow a DO meter from work and do some real world measurements?

I agree cooling the wort down will introduce some DO.

I thought those cubes that the no-chillers use allow air through the plastic. If that is the case then as the wort cools, air would make it way its way through the plastic and into the wort and increase DO.


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## RussTaylor (15/2/09)

QuantumBrewer said:


> Nope.
> 
> Close, but not quite. Actually not close at all, just containing a lot of entrants, judges, stewards, and a RussTaylor.



Closer than you think  ANAWBS is hosted by the Adelaide and Blackwood clubs so without the those clubs, ANAWBS would cease to exist...


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## Bribie G (15/2/09)

kirem said:


> I thought those cubes that the no-chillers use allow air through the plastic. If that is the case then as the wort cools, air would make it way its way through the plastic and into the wort and increase DO.


Don't fancy your chances of breathing inside a cube :lol: 

I no chill in a jerry and give the wort a good splash when pouring it into fermenter. Up to now I have been pitching dry yeast or smacked Wyeast straight from the packs and the lag time has been unacceptable, up to three days to get a good krausen as opposed to K&Ks where I would sometimes have froth shooting through the airlock by the next evening. This time I'm going to make up a starter (nottingham) and will aerate the starter using a stainless steel airstone and build up a better yeast count. That way I've hopefully got it covered both ways.


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## neonmeate (15/2/09)

kirem said:


> Yalumba make some interesting wines, I think they have a 'wild ferment' chardonnay. Yalumba are a very trustworthy company and I think they wouldn't just put wild ferment on the label for something that started fermenting naturally in the winery. I would suspect that they put some effort into making it a true wild ferment.


have seen that one around, but havent tried it yet, will give it a go. 
have had some nice wild ferment whites by seppelt and cape mentelle, the funk seems to make chardys a bit more interesting than they usually are.
what about a nice bretty red.... have heard good things about farr shiraz having brett in it but can't bloody afford it

perhaps i will open and recork some wine bottles with some lambic dregs (like i did with coopers sparkling once) and see what happens after a year...


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## kirem (15/2/09)

BribieG said:


> Don't fancy your chances of breathing inside a cube :lol:



Don't fancy getting inside one without following a confined space entry  



neonmeate said:


> have had some nice wild ferment whites by seppelt and cape mentelle, the funk seems to make chardys a bit more interesting than they usually are.
> what about a nice bretty red.... have heard good things about farr shiraz having brett in it but can't bloody afford it



Brett is mainly considered a fault in wine. There are brett nazis that will 'can anything that has detectable brett and others that look at it as complexing.

I find particular varieties and regions seem to have more of a brett character. Pinot noir and Hunter reds. Having done a reasonable amount of research into Brett during my honours year, I also know that other yeasts can produce 4EP, 4EG 4EC etc. One happens to be Pichia sp. coincidentally when Hunter Valley fruit was examined for yeast species, the fruit had a significantly higher population of Pichia sp.

I don't like brett characters and thanks to my honours year I am very sensitive to it. I don't seek out those wines. A lot of European wines have brett character that they pass off as terrior. Not only do I get aromas, flavour and a metallic sensation that I don't like, I think it masks fruit character.

I'll give it some thought and think of an example that I have tasted recently that it is on the threshold. Bottles that display brett character just get worse.


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## neonmeate (15/2/09)

that's interesting ive always thought i could taste orval in hunter shirazes. but i thought it can't be brett in all of them.

is there a difference between wines where brett gets into the initial fermentation and gets a piece of the action away from the intended yeast, and wines where the brett gets in during maturation (from barrels etc) - surely the high alcohol, high attenuation and low pH of wine would make it hard for brett to get very far and really dominate, once the wine has been fully fermented by normal yeast? 
i know when ive added brett in secondary to very dry beers made with attenuative belgian yeasts, the brett makes a much smaller contribution to the flavour than if it's a beer with a fair amount of residual sugar. i wouldn't have a clue about wine fermentation but surely there are ways to control/limit brett impact, or to use it skilfully in wine?


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## katzke (15/2/09)

BribieG said:


> Don't fancy your chances of breathing inside a cube :lol:
> 
> I no chill in a jerry and give the wort a good splash when pouring it into fermenter. Up to now I have been pitching dry yeast or smacked Wyeast straight from the packs and the lag time has been unacceptable, up to three days to get a good krausen as opposed to K&Ks where I would sometimes have froth shooting through the airlock by the next evening. This time I'm going to make up a starter (nottingham) and will aerate the starter using a stainless steel airstone and build up a better yeast count. That way I've hopefully got it covered both ways.



Starters are not recommended for dry yeast. The dry yeast are charged and ready to go. Making a starter will deplete that energy.

I wonder if you have other problems with nutrients? Magnesium and Zinc are important for yeast health. Maybe try some yeast nutrient as per directions before making a starter with dry yeast.

A starter for liquid yeast will help. One reason why I have switched to dry, I dont want to mess with starters.


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## jonocarroll (15/2/09)

So many replies. Cheers everyone! Good to see a nice healthy discussion - I take it everyone is properly aerated.



Thirsty Boy said:


> My take on it is (and I readily stand to be corrected by actual wine makers AND brewers like kirem and HoppinMad) is that the pitching rates in wine are lower than in beer, because the yeast characteristics play a much bigger part in wine flavour profiles that they do in beer.


From what I heard from one particular winemaker, the opposite was true (at the very least for the reislings he was talking about). They use a very neutral yeast, leaving the juice flavours to develop as they are. Not sure in general.



kirem said:


> Yalumba make some interesting wines, I think they have a 'wild ferment' chardonnay. Yalumba are a very trustworthy company and I think they wouldn't just put wild ferment on the label for something that started fermenting naturally in the winery.


I was up at Crabtree in Clare and they have a few open fermenters that 'just get going naturally.' Damn fine wines. From their site;



> _Fine Chardonnay was sourced from the Smith family vineyard in North Clare and rich Viognier grapes were hand picked off the Bourne family "Folly" Vineyard in Watervale. Half of the juices were barrel fermented in second year oak relying on wild yeast. The lees were stirred periodically. The other half of the juices were cold fermented in stainless steel utilising commercial yeasts. Each variety was fermented separately prior to blending as finished wine. _






RussTaylor said:


> Closer than you think  ANAWBS is hosted by the Adelaide and Blackwood clubs so without the those clubs, ANAWBS would cease to exist...


But it's not the 'club' that I mentioned. I certainly wasn't talking down ANAWBS - which rocks heartily.

Cheers everyone! Without trying to sound too greedy, did anyone have an answer for my stir-plate starter question?



> On a slight side note - to the people who use a stir-plate with their starters; the reason for stirring is to keep the yeast in suspension and to continually introduce O2 while allowing CO2 to escape, yes? If the starter is sealed, how does more O2 get in? Not saying it doesn't, just asking.


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## Adamt (16/2/09)

The answers to your stir-plate questions:

"Yes." , and "It doesn't, that's why brewers loosely cover with alfoil/cling wrap/whatever."


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## muckanic (16/2/09)

Thirsty Boy said:


> My take on it is (and I readily stand to be corrected by actual wine makers AND brewers like kirem and HoppinMad) is that the pitching rates in wine are lower than in beer, because the yeast characteristics play a much bigger part in wine flavour profiles that they do in beer. In beer, yeast characteristics are _important_... but in most styles it is a very subtle difference between the yeast being an important sub character to the malt and hops, and it dominating unpleasantly. Winemakers do a LOT more with their fermentation control than brewers do to manipulate things beyond just pitching rates. If it was just pitching rates and strain characteristics... I could be a wine maker, and I know bloody well that I couldn't.



Actually, it's the opposite. Almost all wines show off the ingredients and not too much more, whereas certain beers give the yeast equal billing with the ingredients. About the most complex thing winemakers do is to encourage a malo-lactic, tertiary ferment.



neonmeate said:


> is there a difference between wines where brett gets into the initial fermentation and gets a piece of the action away from the intended yeast, and wines where the brett gets in during maturation (from barrels etc) - surely the high alcohol, high attenuation and low pH of wine would make it hard for brett to get very far and really dominate, once the wine has been fully fermented by normal yeast?



The phenomenon known as "mouse" is fairly established within winemaking assessment, and I believe this is due to Brett. It emerges late in the piece.


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## Bribie G (17/2/09)

katzke said:


> Starters are not recommended for dry yeast. The dry yeast are charged and ready to go. Making a starter will deplete that energy.
> 
> I wonder if you have other problems with nutrients? Magnesium and Zinc are important for yeast health. Maybe try some yeast nutrient as per directions before making a starter with dry yeast.
> 
> A starter for liquid yeast will help. One reason why I have switched to dry, I don't want to mess with starters.



Reason I decided to do a starter for Nottingham was that the last couple of brews using this yeast have taken up to three days to develop a krausen. The last brew, a partial with well aerated wort was pitched on a Sunday and didn't get a krausen or much airlock activity till Wednesday, in brew fridge at 20. I love Notto because it is _usually_ fast and furious and produces a clean well flocculated beer. I would like it to be done in five days so I can then cold condition for a week, not just getting going after three days.

So yesterday I did the same recipe which is identical to the first one. Yesterday morning I started a Nottingham in a 1.5L bottle with a bit of LDME and some dex, by the evening it was going nuts and I pitched it last night. This morning there is a magnificent krausen and airlock blooping every two seconds.

The recipe is identical and it's in the brew fridge at the same temp as the last one.

Coopers Lager
1 kg dex
a 5L cube of AG wort produced in the same batch as the first brew
Nottingham from the other side of the twinpack from Ross. (I didn't save yeast cake from the last brew because I was worried about the yeast health due to the long fermentation)

So there you go  
I'll be interested to see when the new brew attenuates.


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## jonocarroll (20/2/09)

Adamt said:


> The answers to your stir-plate questions:
> 
> "Yes." , and "It doesn't, that's why brewers loosely cover with alfoil/cling wrap/whatever."


I somewhat forgot about this for a little while. Now a follow up;

I take it your "Yes" refers to keeping the yeast in suspension, and ventilating CO2?

If no more O2 gets introduced, I guess it makes sense to get the starter as oxygenated as possible to start with. Stirring won't introduce any more O2 if there's no more to add (sealed flask), but it will make sure that the yeast can access the maximum amount in the fluid.

Despite the risk of infection, would it be wise to have a method of introducing more oxygen to the starter to make sure you build up to the correct pitching rate. Of course, you don't want to overpitch necessarily, but you want to get it right. I think I heard someone say that there was a method, but it was a PITA.

Cheers all :icon_cheers:


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## Kai (20/2/09)

Darren said:


> I have never airated my wort and never had a stuck ferment ( I airate my starters by shaking when I use them). I fail to see how cooled wort is O2 free. There is always a little bit of splashing when I transfer from my kettle. Only way I can imagine O2 free wort is if one was to "no-chill" then ferment in the same cube.
> 
> EDIT: Wine must would also be 2-3 times the OG of most beers, but the yeast manages without airation. Airation on the HB scale, BOLLOCKS
> 
> ...



Wine must hasn't had all the DO boiled off... Something that's not going to be replaced just by splashing wort into a plastic fermenter.


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## suorama (26/2/09)

OT?

Those who give pure Oxygen to wort. Is there any hop aroma losses? Usually thinking, if hop aroma are gone reason or other, that was oxy what are destroy it.


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## chappo1970 (9/3/09)

Rather than start new thread I remembered this one. So I have done the unspeakable I pitched 3ml of olive oil into my latest brew instead of aerating the wort. Not only did it kick off well by this evening I had a very healthy krausen forming in the fermenter approximately 24hrs after pitching rehydrate S05.

So why did I do this? I guess I'm new to AG and don't have paradyms that more experiencd brewers have and in part I have a tinkering/experimenting nature. But more to the point on Sunday just gone at the MT Tamborine BABBS brewery day the head brewer, Frank, from Eagle Heights Brewery told us that he doesn't aerate his wort at home. He whacks in 3ml of olive oil into his wort prior to pitching his yeast. Said it saves his about 40mins of aerating that he used to do to get o2 into the wort. Basically olive has all the sterols and unsaturated fatty acids for the yeast cell walls to do what they do. As per previous discussion on this tread. Anyway via this thread and a reasonable explaination from Frank I thought why not give it a go? 

Anyway I guess the results will in the tasting in few weeks time.

EDIT: Should drink tea and type


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## Bribie G (9/3/09)

I can see the logic of this, like feeding my magpies of an evening I make sure they get fatty bits like lamb chop leftovers because it gives them the nutrients they maybe lack from pecking around in the park all day.

However one thing I would be worried about is that if you put in too much olive oil, after the yeasties have done their cell wall thing and gone on to greater things, any excess remaining oil could be a major head killer in the finished beer.

Keep us posted Chappo.


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## JonnyAnchovy (9/3/09)

Chappo said:


> Rather than start new thread I remembered this one. So I have done the unspeakable I pitched 3ml of olive oil into my latest brew instead of aerating the wort.




3ml seems like a huge ammount - all the accounts I've seen call for less than .5ml for a regular size batch. I'm really keen to see how this turns out - I've heard of plenty of people trying it here, but haven't heard any reports of the results yet. Keep us posted!


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## chappo1970 (9/3/09)

That what's I thought in my limited knowledge and reading but I did ask Frank again separately later on and he was pretty positive about the 3ml to 21lt of wort. Anyway I will keep you posted to the results.


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## JonnyAnchovy (9/3/09)

I think this was one of the orignal articles outlining the process. in the experiemnt they do a 360 HL batch with 15ML of Olive oil, if i'm not mistaken that'd mean around 0.01ml for a regular 22L batch. 

Someone please correct my math!


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## chappo1970 (9/3/09)

Nothing wrong with your maths JA. Read that article again last night as well. As I said he was very insistant on the 3ml. Anyway I'm sure time will tell.


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## JonnyAnchovy (9/3/09)

Let me know how it goes- I'm thinking of going down the ooil path soon.


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## katzke (10/3/09)

JonnyAnchovy said:


> I think this was one of the orignal articles outlining the process. in the experiemnt they do a 360 HL batch with 15ML of Olive oil, if i'm not mistaken that'd mean around 0.01ml for a regular 22L batch.
> 
> Someone please correct my math!



I listened to the program that had the info on Olive Oil and I remember them saying something about a toothpick and the small drop that would form on the tip being almost too much. I think the program was linked from one of the posts in this thread but can not say for sure with out looking back.

I also recall something about the oil being added to the starter to give the yeast cells extra nutrient that is used when they divide in the wort.


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## Wolfy (10/3/09)

katzke said:


> I listened to the program that had the info on Olive Oil and I remember them saying something about a toothpick and the small drop that would form on the tip being almost too much.


That's exactly what I remember also, a 3ml measure must mean its a big toothpick. 
At the same time it's hard to imagine how 0.01ml does much either.


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## muckanic (10/3/09)

In practice, you probably couldn't accurately do less than about 0.5 mL using something like a medicine dropper. Apart from the impact on head retention, I am wondering if 3 mL of olive oil could have flavour effects, in which case a cereal oil like from corn, wheatgerm or rice could have advantages even if the fatty acid profile is not quite ideal. I also occasionally use raisins as a vinosity booster in some old ale styles, and I used to fret about getting rid of all the vegetable oil coating. Maybe not any more? 

There is of course always the tried and trusted route of using break as the unsaturated fatty acid source instead of throwing it down the drain! Hot break can result in some sulphides that may or may not vent off eventually, but cold break is usually OK. I know some brewers have concerns about the potential for lipid staling, but that presumably applies whether the extra lipids come from the ingredients, supplementary vegetable oil or even yeast. Plus, this effect would be presumably offset by the lack of deliberate O2 introduction (and consequent staling), bearing in mind the whole time that yeast is a reductant anyway.


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## chappo1970 (10/3/09)

After this all popped up last night I couldn't help but be a little worried. The old "Have I ruined my brew" shuddered thru my mind. So I checked the eye dropper I used, it was only 0.5ml, I thought it was 1.5mil, so it would appear that I only added 1ml not 3ml as previously stated. However it's still 100 times the amount if you go off 0.01ml. I guess I will just have to wait and see huh?


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## apd (10/3/09)

Chappo said:


> After this all popped up last night I couldn't help but be a little worried. The old "Have I ruined my brew" shuddered thru my mind. So I checked the eye dropper I used, it was only 0.5ml, I thought it was 1.5mil, so it would appear that I only added 1ml not 3ml as previously stated. However it's still 100 times the amount if you go off 0.01ml. I guess I will just have to wait and see huh?



I'm sure you'll be right, Chappo. Even 3ml in 20L or so is a tiny amount. And if it's still floating around when you rack to secondary or bulk prime, you can easily leave it in with the trub.

I tried the olive oil thing by dipping the end of my thermometer in oil and sticking that in a starter. The starter was fine. The wort was never aerated.

It really makes sense to be aerating (or oiling) your yeast during the starter phase, not your wort. It's the yeast that needs the oxygen or sterols (or whatever is in the olive oil), not the wort. Once you've built up your starter, the yeast don't need any more of the nutrients required for replication, so why put those nutrients in the wort and potentially make it stale?

Andrew


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## muckanic (10/3/09)

With oiling a starter, the issue arises of how the yeast know when enough is enough (ie, when to stop replicating and start fermenting). They very well could optimise the ferment of the starter, but they have no way of knowing what the intended ferment size is. With O2, they stop replicating when the supply is turned off. Maybe this is an argument for adding the oil in a similar progressive fashion, or for oiling the actual ferment as well?


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## chappo1970 (11/3/09)

After my little escapades this week eg trying the olive oil. I'm still quietly pooping my self BTW. I have been trying to read and absorb as much information on yeasts, life cycles, farming, cultivating etc. It's a very exhaustive subject just on it's own.
Anyway because of my welding etc I have a "E" sized bottle of medical grade O2 that I could use to aerate the wort via an airstone. What isn't overly clear on the subject of pure O2 aeration, well to me anyway, is how much? for how long? at what flow rate? Nothing definitive more stabs in the dark FWIW.

newguy breifly mentions something below and there are few more references of "give it a blast for 30 secs" kinda of stuff but what is the proper procedure for O2 injection to obtain the 10ppm required? Is there one?

Anyway I would appreciate any advice or help on the subject from the AHB guru's.




newguy said:


> I give my wort a shot of pure O2; 30 seconds for the first pitch from a starter and 0-15 seconds if repitching onto a yeast cake (depends on the beer) - very high gravity brews usually get more. I've always built up pretty large starters but only relatively recently have I started using O2. I started using O2 because I was getting stuck fermentations even though my lag times after pitching were reasonable (6 - 12 hours). For me, O2 was introduced as a fix to a problem I was consistently having, not because the homebrewing literature said I needed it or because I was worried I was underpitching. Even though I have no way to confirm/count the number of active cells I pitch, I'm pretty sure it's in the proper ballpark.


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## alowen474 (11/3/09)

I had a bit of a look at oxygenating wort and Greame from Murrays sent me the following advice
"To put things basically, you need, depending on who you want to listen to, 14ppm of oxygen, so in 56 litres you need around 1 litre of O2 (56 x .014), but at 20c you will only dissolve around 50% into the wort, so you therefore need 2 litres of O2. If you use O2 you will need a flowmeter (litres/min) on the oxygen so you inject it at 1litre/min for two mins, or 2litres/min for 1 min, etc. This is a bit simplistic but works ok...."

Some good info.


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## Ross (11/3/09)

Chappo said:


> Anyway because of my welding etc I have a "E" sized bottle of medical grade O2 that I could use to aerate the wort via an airstone. What isn't overly clear on the subject of pure O2 aeration, well to me anyway, is how much? for how long? at what flow rate?
> 
> Anyway I would appreciate any advice or help on the subject from the AHB guru's.



Chappo,

Standard brew - 30 seconds with a 0.5 micron airstone. The flow rate should be set so the oxygen bubbles are only just breaking the surface.
These timings are through actual experiments using a dissolved oxygen meter, as I too couldn't find a definitive answer.
Happy to demo, next time you drop by the shop.

Cheers Ross


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## newguy (11/3/09)

beerforal said:


> I had a bit of a look at oxygenating wort and Greame from Murrays sent me the following advice
> "To put things basically, you need, depending on who you want to listen to, 14ppm of oxygen, so in 56 litres you need around 1 litre of O2 (56 x .014), but at 20c you will only dissolve around 50% into the wort, so you therefore need 2 litres of O2. If you use O2 you will need a flowmeter (litres/min) on the oxygen so you inject it at 1litre/min for two mins, or 2litres/min for 1 min, etc. This is a bit simplistic but works ok...."



I agree that if you were bubbling pure oxygen through water, then the 50% absorption rule would apply as the bubbles would quickly burst. However, when you bubble oxygen through wort, the oxygen doesn't escape the wort at all - it forms a thick, krausen-like foamy layer on top of the wort which doesn't subside. The bubbles simply don't "pop." This nice foamy layer is where the yeast can do their thing and reproduce because there is such a large surface area of wort in contact with pure oxygen. I'm pretty sure that the absorption is close to 100% in wort......if a proper SS airstone is used.

Chappo: Read this, particulary the graph on page 4. Unfortunately they didn't investigate pure oxygen with an airstone. However, this presentation does tie DO levels to the amount of time pure oxygen is used. You'll have to scroll through quite a few pages to get to the good stuff - maybe 20 or 30.


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## newguy (11/3/09)

Suorama said:


> OT?
> 
> Those who give pure Oxygen to wort. Is there any hop aroma losses? Usually thinking, if hop aroma are gone reason or other, that was oxy what are destroy it.



No loss that I can discern. Pumping pure O2 through an airstone into wort results in no bubbles that break, therefore there is no vapour loss from the wort. There may be a breakdown mechanism whereby the oxygen interacts with the hop compounds but, again, I haven't noticed a difference in my beers.


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## chappo1970 (11/3/09)

Thanks guys now I am starting to get somewhere. But you can see from the below quotes where my confusion comes from. All these quotes from the thread, in fact this one BTW. It just seems to me that the subject of O2 aeration and the amounts are more or less subjective and open to opinion and interpretation. 10ppm, 5ppm Ale, 10-12ppm lager and 14ppm carte blanche. I'm not doubting anyone knowledge on the subject but which is the right answer?



hockadays said:


> ...get the dissolved O2 up to 10ppm...





kirem said:


> ....
> * Ale yeasts need about 5 parts oxygen per million in wort, while lagers can need 10 to 12 parts oxygen per million.






beerforal said:


> ...14ppm of oxygen...






Ross said:


> Chappo,
> 
> Standard brew - 30 seconds with a 0.5 micron airstone. The flow rate should be set so the oxygen bubbles are only just breaking the surface.
> These timings are through actual experiments using a dissolved oxygen meter, as I too couldn't find a definitive answer.
> ...


I will be on Saturday Ross for some more grains etc so I look forward to catching up and having a look. Thanks for the offer.



newguy said:


> I agree that if you were bubbling pure oxygen through water, then the 50% absorption rule would apply as the bubbles would quickly burst. However, when you bubble oxygen through wort, the oxygen doesn't escape the wort at all - it forms a thick, krausen-like foamy layer on top of the wort which doesn't subside. The bubbles simply don't "pop." This nice foamy layer is where the yeast can do their thing and reproduce because there is such a large surface area of wort in contact with pure oxygen. I'm pretty sure that the absorption is close to 100% in wort......if a proper SS airstone is used.
> 
> Chappo: Read this, particulary the graph on page 4. Unfortunately they didn't investigate pure oxygen with an airstone. However, this presentation does tie DO levels to the amount of time pure oxygen is used. You'll have to scroll through quite a few pages to get to the good stuff - maybe 20 or 30.



:icon_cheers: Thanks newguy for the links I will digest that info over lunch.


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## onescooter (11/3/09)

Just wondering what the difference is between medical grade 02, and run of the mill 02 from an oxy acetylene kit.


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## mika (11/3/09)

Not a lot if you run it thru a HEPA filter.


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## chappo1970 (11/3/09)

newguy said:


> Chappo: Read this, particulary the graph on page 4. Unfortunately they didn't investigate pure oxygen with an airstone. However, this presentation does tie DO levels to the amount of time pure oxygen is used. You'll have to scroll through quite a few pages to get to the good stuff - maybe 20 or 30.




Thanks newguy! Great info BTW and exactly what I was looking for, some science to back up the methods vs results vs BS vs Intermernet Genius vs urban legend... you get the idea. I owe you beer if your ever this way! :icon_cheers:

EDIT: Looks like I will buy an airstone off ya Ross BTW. Keep one aside for me.


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## muckanic (12/3/09)

At the risk of stating the obvious, all this stuff on flow-rates and whathaveyou is critically dependant on whether one is oxygenating a starter or the whole wort. It was concluded way back at the start of this thread that oxygenating the starter alone is preferable in order to avoid beer staling. It would sure also cut down on O2 consumption which, unlike air, isn't free. I would add another, less-recognised point: that replicating yeast puts out a different spectrum of byproducts than fermenting yeast. I think this is an implicit reason why folks sometimes recommend throwing the starter supernatant away, although those byproducts could actually be desirable in certain beer styles. A final bleeding obvious observation: oiling the wort is not a direct substitute for big yeast starters, due to the greater yeast growth in the former.


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## alowen474 (12/3/09)

muckanic said:


> At the risk of stating the obvious, all this stuff on flow-rates and whathaveyou is critically dependant on whether one is oxygenating a starter or the whole wort. It was concluded way back at the start of this thread that oxygenating the starter alone is preferable in order to avoid beer staling. It would sure also cut down on O2 consumption which, unlike air, isn't free. I would add another, less-recognised point: that replicating yeast puts out a different spectrum of byproducts than fermenting yeast. I think this is an implicit reason why folks sometimes recommend throwing the starter supernatant away, although those byproducts could actually be desirable in certain beer styles. A final bleeding obvious observation: oiling the wort is not a direct substitute for big yeast starters, due to the greater yeast growth in the former.


Being reasonably new to aeration and oxygenation, wouldn't aerating the starter only help grow a healthy starter?
Isn't the starter the vehicle to provide enough yeast cells so that the reproduction phase of the fermentation cycle is reduced to a healthy level? If this was the case the wort would still need oxygen at 10-15ppm for the yeast to grow to the right quantity would it not?
Maybe I need to read some more!!


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## muckanic (12/3/09)

Chappo said:


> And I guess the whole olive oil thing leaves me red faced and a pretty big slow moving target for ya huh?  Or was that too bleeding obvious?
> 
> What may seem bleeding obvious to you, is not to me. Why not try to be less condecending? I don't know you from a bar of soap and you certainly don't know me which I guess makes all the easier. It's a forum not a lecture hall.



Mate, try switching to lite! You're not anybody's target and I for one am interested in all these olive oil experiments. I was actually throwing up more questions than answers, so I'm hardly in a position to lecture anyone.

Peace :icon_chickcheers:


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## hazard (23/3/09)

Chappo said:


> That what's I thought in my limited knowledge and reading but I did ask Frank again separately later on and he was pretty positive about the 3ml to 21lt of wort. Anyway I will keep you posted to the results.


Chappo, do you have results to report? I am very keen to try this technique, would appreciate some feedback on how your brew went,

hazard


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## chappo1970 (23/3/09)

Hazzard it's perfect IMO. No noticable faults what so ever. I kegged it last night, bottled a couple of samples for the monthly BABBS meeting (I will let them judge as I could be biased) and sipping away on what is almost a perfect Little Critters Bright Ale. There is definitely something to this so I am going one further this time. 

I did a double batch of Moonshadow's Drowned Faery Golden Ale. Same batch, same boiler and same cube. I will brew 18lts with Oxygen aeration and 18lts with 1ml of olive oil. I will make a 3lt starter and pitch 1.5lt into each batch. Therefore the ONLY variable will be he aeration method. I going to try to note high kraussen time, attenuation and overall fermentations times. Just waiting to get an Irish red ale out of the ferment fridge first so I can get both in there at the same time.

BTW: Head retention is fine


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## hockadays (23/3/09)

beerforal said:


> Being reasonably new to aeration and oxygenation, wouldn't aerating the starter only help grow a healthy starter?
> Isn't the starter the vehicle to provide enough yeast cells so that the reproduction phase of the fermentation cycle is reduced to a healthy level? If this was the case the wort would still need oxygen at 10-15ppm for the yeast to grow to the right quantity would it not?
> Maybe I need to read some more!!




I came to the same conclusion when reading the start of this thread.


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## Mantis (23/3/09)

Me too. Since going to BIAB and no chill, my brews are taking so much longer to kick off. 

Before, I was doing partials (BIAB), and throwing the whole contents of the kettle in the fermenter break and all. Then giving the contents a damn good thrashing with a long spoon before pitching yeast. These would all be showing good signs of fermentation within hours.

Now with the no chilling and biab, I am leaving most of the hot break behind in the kettle, no chill and leave more break behind in the cube. Now it takes from the morning of pitching to the next day before fermentation kicks in properly. 

I dont use, and never have used starters so, maybe this is why so many do

If a wee drop of oil will help, I would give it a go :icon_cheers:


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## Mantis (23/3/09)

Jeez, you have to type quick here
Thanks Chappo,, it sounds promising eh


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## mika (24/3/09)

hockadays said:


> I came to the same conclusion when reading the start of this thread.



Yeast needs oxygen to grow, you need oxygen within the wort you're pitching into to allow the yeast to multiply without stress.
If you oxygenate your starter, then your starter has nice healthy yeast, then as soon as you throw them into a full size batch, with no oxygen, they have to draw on their reserves to reproduce and they get stressed and can throw up by-products that will affect the taste. Unless you're starter contains enough yeast that it won't reproduce, but then without any kind of reproduction you'll lose your ester production, probably fine for a lager, but a bit bland in an english ale.
It's a fine balancing act, if you're looking to get it 100% right. You've got to remember that yeast don't want to make alcohol, it's bad for them. They only start producing alcohol when there's no other option.
If you only have the ability to oxygenate the starter, fine go with that, it's better than nothing and a lot of people have been getting away with that (or less than that) for a long time. But if you can oxygenate the starter and the wort you're pitching too, now you're really brewing.


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## hazard (24/3/09)

Chappo said:


> Hazzard it's perfect IMO. No noticable faults what so ever. I kegged it last night, bottled a couple of samples for the monthly BABBS meeting (I will let them judge as I could be biased) and sipping away on what is almost a perfect Little Critters Bright Ale. There is definitely something to this so I am going one further this time.
> 
> BTW: Head retention is fine



Thanks Chappo, sounds good. I will be brewing something next weekend (Irish Red Ale methinks) so will try this. Can I confirm the process:
1. make starter - approx 1.5 L. I don't have a stir plate, so i use a 2L juice bottle covered with cling wrap and shake every time I walk past it.
Question - is a stir plate even needed? If olive oil replaces oxygen then there's no need for a stir plate? I have been following the "tight arse stir plate" thread with interest because I am a tight arse, but if oil is just as good then I can save a few more bucks.
2. add around 0.5ml olive oil (i have seen suggestions that this should be done by dipping a toothpick or pin into oil then dipping into the starter. 
Question - when to add oil? When yeast is added to starter? At high krausen? When fermentation is completed?
3. After wort reaches fermention temp, add starter. No stirring or aeration required.
Question - no oxygen added to wort, is there any more oil needed in the wort?

I am getting really good heads on my beer now and am glad to hear that small amount of oil doesn't affect head retention. Thanks for any further advice on this.

Regards, Hazard


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## jonocarroll (24/3/09)

mika said:


> Yeast needs oxygen to grow, you need oxygen within the wort you're pitching into to allow the yeast to multiply without stress.
> If you oxygenate your starter, then your starter has nice healthy yeast, then as soon as you throw them into a full size batch, with no oxygen, they have to draw on their reserves to reproduce and they get stressed and can throw up by-products that will affect the taste. Unless you're starter contains enough yeast that it won't reproduce, but then without any kind of reproduction you'll lose your ester production, probably fine for a lager, but a bit bland in an english ale.
> It's a fine balancing act, if you're looking to get it 100% right. You've got to remember that yeast don't want to make alcohol, it's bad for them. They only start producing alcohol when there's no other option.
> If you only have the ability to oxygenate the starter, fine go with that, it's better than nothing and a lot of people have been getting away with that (or less than that) for a long time. But if you can oxygenate the starter and the wort you're pitching too, now you're really brewing.


If yeast became stressed by going from starter to unaerated wort, wouldn't they get stressed once they've used up the oxygen in an aerated wort? You're also assuming that the yeast is pitched at the moment the oxygen runs out - surely it's possible that the yeast have started the fermentation phase in the starter already.

The point of this thread was the question - "do you need to aerate the wort if you've aerated the starter enough?" The critical part for any answer is assuming that the starter _has been aerated enough_. Several options exist beyond this - pitch the entire starter, esters and all; pitch after high-krausen; etc.

Many people have produced arguments *against* aerating the wort - oxidisation for one - your argument of 'yes, you've gotta' will need some more support.


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## Sammus (24/3/09)

onescooter said:


> Just wondering what the difference is between medical grade 02, and run of the mill 02 from an oxy acetylene kit.



I remember this being discussed at length several times over in many threads a few years back, the general consensus was that the medical grade O2 has a different thread on the cylinders. The gas itself - same O2 from the same tank, as far as hiring from BOC is concerned anyway, which was verified by several BOC employees.


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## muckanic (24/3/09)

mika said:


> but then without any kind of reproduction you'll lose your ester production, probably fine for a lager, but a bit bland in an english ale.



Bear in mind there are esters and esters. IIRC, the pathways for the solventy acetate esters are different than for the fruitier and higher weight esters, which rely on fusel oil production. I don't have Fix's book at my fingertips to be any more specific than that - will have to look it up.



mika said:


> If you only have the ability to oxygenate the starter, fine go with that, it's better than nothing and a lot of people have been getting away with that (or less than that) for a long time.



Except that pros doing continuous production probably aren't too worried about starters either, as they often have a yeast cake to work with. I wonder how many of them oxygenate the wort as well in that case? In addition, how many amateurs are going to the bother of separating their wort from the cold break?

As a test, I added 3mL/23L olive oil to an all-sugar brew of SG 60 that had stalled on me at about 5% ABV. It didn't revive fermentation, quite possibly because the lipids were being added later than when they were needed. It did however result in a visible globule slick and the aroma of pizza. Once again, those problems could have been caused by the oil not being assimilated properly, but just from that experience I would guesstimate that those quantities are way, way too much. Rice bran oil has a much more neutral nose, at the disadvantage of a lower monounsaturate ratio.


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## newguy (24/3/09)

From personal experience, no aeration = stuck fermentation + "Belgian" character, though not as pleasant as a Belgian beer. It is tough to describe, but once you taste it, you know the flavour.

A local micro has related a story, many times, of a brewer he used to employ who hated cold break and took any step he could imagine to separate the wort from the cold break. He was eventually let go because every batch he brewed ended up being stuck (underattenuated) and nothing they did would rouse the yeast and coax it to properly attenuate the wort. Once they went back to the normal procedure which didn't separate cold break from the wort, the problems went away.


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## jonocarroll (24/3/09)

newguy said:


> From personal experience, no aeration = stuck fermentation + "Belgian" character, though not as pleasant as a Belgian beer. It is tough to describe, but once you taste it, you know the flavour.


'no aeration' at all or no aeration of the wort, but aeration of the starter? 



newguy said:


> A local micro has related a story, many times, of a brewer he used to employ who hated cold break and took any step he could imagine to separate the wort from the cold break. He was eventually let go because every batch he brewed ended up being stuck (underattenuated) and nothing they did would rouse the yeast and coax it to properly attenuate the wort. Once they went back to the normal procedure which didn't separate cold break from the wort, the problems went away.


Seems like a funny way to solve a problem. The words 'cause' and 'effect' come to mind. It may very well have been that the steps taken to separate the wort added in a step that ruined things, rather than the separation itself causing the problems. Throwing out the baby with the bathwater, methinks.


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## newguy (24/3/09)

I aerate my starters but there was a time that I wasn't aerating my wort at all. Every batch would 'stick' and would take on distinctly Belgian-type characters. Very unpleasant.

The micro & the problem was entirely due to the separation of the cold break. Every other procedure was and is identical to what they still do now but the problem has disappeared. The only extra thing that brewer was doing was waiting until the cold break settled out of the tank, then he pumped the clear wort over to a different fermenter where the yeast was pitched. Aeration took place via filtered high pressure air (from a compressor) on the way from the kettle to the first tank. The time spent in the first tank, prior to being pumped to a second, was maybe an hour at most. The separation from the cold break was definitely the issue....at least in that brewery. I've never separated my wort from the cold break so I can't comment on what would happen if I did. In this case, however, I think it's pretty clear that immediate separation from cold break is bad. For no chillers, where the wort remains in contact with the cold break for quite some time, perhaps the cold break is slowly reabsorbed...or a portion of it is.


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## jonocarroll (24/3/09)

newguy said:


> I aerate my starters but there was a time that I wasn't aerating my wort at all. Every batch would 'stick' and would take on distinctly Belgian-type characters. Very unpleasant.


That is what I would expect to happen with no aeration at all, but that's off-topic for here, since we are discussing the issue of good starter aeration and it's effect the requirement for wort aeration.



newguy said:


> The micro & the problem was entirely due to the separation of the cold break. Every other procedure was and is identical to what they still do now but the problem has disappeared. The only extra thing that brewer was doing was waiting until the cold break settled out of the tank, then he pumped the clear wort over to a different fermenter where the yeast was pitched. Aeration took place via filtered high pressure air (from a compressor) on the way from the kettle to the first tank. The time spent in the first tank, prior to being pumped to a second, was maybe an hour at most. The separation from the cold break was definitely the issue....at least in that brewery. I've never separated my wort from the cold break so I can't comment on what would happen if I did. In this case, however, I think it's pretty clear that immediate separation from cold break is bad. For no chillers, where the wort remains in contact with the cold break for quite some time, perhaps the cold break is slowly reabsorbed...or a portion of it is.


This is also off-topic. My comment was merely that in order to understand _why_ something happened, you need to look a lot further than just the details of _what_ happened. Your statement 'I think it's pretty clear that immediate separation from cold break is bad.' is bad science, but I won't discuss it further right here. I will however provide a more humorous example...


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## muckanic (25/3/09)

hazard said:


> 1. make starter - approx 1.5 L. I don't have a stir plate, so i use a 2L juice bottle covered with cling wrap and shake every time I walk past it.



It would probably be better to pour the contents roughly into another bottle about half a dozen times if you could be bothered. Also, a fibrous plug in the neck rather than the cling wrap would allow the starter to absorb more oxygen when it is not being agitated. Yes, this increases the risk of picking up a bug, but it's hardly as if anyone, stir-platers included, is talking about micro-filtered air in the first place.

One idea I have been toying with is to try and adapt a garden sprayer for starter growing duty, thanks to the ability to pump it up with pressurised air. The main problem of course is how to vent off the CO2 and trade it for O2. The safety relief valve will presumably stop the container from blowing up but it won't stop the CO2 pressure from impeding growth, so the sprayer would somehow or other need to be vented periodically. I guess the sequence would be vent CO2, pump air, shake, wait for O2 to be consumed (how long?), then vent again. This process is crying out for an automated approach, but then you might as well buy an industrial incubator!


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## pdilley (25/3/09)

Chappo said:


> BTW: Head retention is fine



+1 for having the balls to be a mad scientist and push the knowledge base


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## hazard (31/3/09)

JonnyAnchovy said:


> I think this was one of the orignal articles outlining the process. in the experiemnt they do a 360 HL batch with 15ML of Olive oil, if i'm not mistaken that'd mean around 0.01ml for a regular 22L batch.
> 
> Someone please correct my math!


If you look at the original thesis, they state that they did several tests, ranging from 1 ml of oil per 67 Billion yeast cells to 1 ml of oil per 25 billion yeast cells. A smack pack is 100 billion yeast cells, so this implies about 1.5 to 4 ml of oil would be added for one smack pack. I think packs of dry yeast are a similar size, so this is still OK. Therefore Chappo appears to be spot on with 3 ml. They also added oil to starter 5 hours before pitching.

I am still to try this but keen to give it a whirl next time. All results in the thesis show that they achieved their aim - and the brewery packaged and sold the beer, so they were happy with results.


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## JonnyAnchovy (15/5/09)

Any further updates Chappo??


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## Bribie G (15/5/09)

Anecdotally, I usually only aerate by pouring from cube to fermenter with a fair amount of frothing and have never had a stuck fermentation. Also I believe it depends a lot on the yeasts. For example I'm currently experimenting with Mauri yeasts for my Aussie Lagers and olds. The Mauri Lager yeast (aka Morgans Lager yeast etc) has very low oxygen requirements according to their website and sure enough did its thing vigorously in a sealed fermenter and finished in five days and is currently in cold conditioning. On the other hand some highly flocculating yeasts like Ringwood and Wyeast West Yorkshire do best if they are thrashed to death twice a day and thoroughly aerated during fermentation. I'm about to give my Ringwood a spanking right now.

I always aerate my starters nowadays and use the Buttersd70 method of placing in a flask (schott bottle in my case) in a prominent high traffic area of the house and shake it to buggery whenever I'm passing. :beerbang:


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## chappo1970 (15/5/09)

JonnyAnchovy said:


> Any further updates Chappo??


JA,
I have brewed now about 6 batches with the Olive oil in starters and the wort plus about 4 with using oxygen to aerate the wort. What have found is that the Olive Oil brews do kick off quicker and more lively than the oxygen aeration IMO. I have done a side by side using the same wort with a LAGER but unfortunately got too busy with day to day life that I couldn't make the observations that I want to. I guess until I can actually get some serious holiday time to do this properly it's pretty much going to be my word against the known science.

I have also been feeding the results to unawares Brewers I know that have the experience to detect faults and traits. Thus far NO ONE has picked it at all. Certainly no one has detected yeast stress thus far. I did have a brew that had some DMS issues which was more me and my process than to do with aeration. 

Currently I have backed off the amount from 3mls to 1.5mls directly in the wort and to be honest I have not noticed any difference in the results. In the starters I have stuck to 0.5mls as that is the smallest I can measure ATM. I am waiting for a better more accurate pipette to arrive stortly so I can make smaller increments of additions.

Chappo


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## Bribie G (15/5/09)

Interesting, I've got a cube ready and a starter on the go (a n Aussie Dark) for pitching this afternoon or tomorrow AM at the latest, I'll get out the ALDI Oro y Sol and give it a go this time. A level teaspoon is around 5 ml so I should be able to do a roughish dose. I'm using US-05 which I have always found a bit slowish compared to kit yeasts and Notto so if there is a significant difference in activity it should be discernible, being a yeast I'm well familiar with.


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## chappo1970 (15/5/09)

BribieG said:


> Interesting, I've got a cube ready and a starter on the go (a n Aussie Dark) for pitching this afternoon or tomorrow AM at the latest, I'll get out the ALDI Oro y Sol and give it a go this time. A level teaspoon is around 5 ml so I should be able to do a roughish dose. I'm using US-05 which I have always found a bit slowish compared to kit yeasts and Notto so if there is a significant difference in activity it should be discernible, being a yeast I'm well familiar with.



BribieG don't you have a pocket sparkler you could use to measure the dose?

I would love to hear how it goes for you. I'm sure we can compare notes at the next BABBS meeting.

Chappo


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## Bribie G (15/5/09)

My pocket sparkler is 30 ml - a Man's pocket sparkler but I have to go up to the Chemists later so if I remember I'll get a 3ml (Nice to see that that poor drug addict man is cutting down on his doses :lol: )

It's going to take a *lot* of extremely fast talking if the cops ever decide to pop into my garage to see what's going on :unsure:


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## chappo1970 (15/5/09)

BribieG said:


> My pocket sparkler is 30 ml - a Man's pocket sparkler but I have to go up to the Chemists later so if I remember I'll get a 3ml (Nice to see that that poor drug addict man is cutting down on his doses :lol: )
> 
> It's going to take a *lot* of extremely fast talking if the cops ever decide to pop into my garage to see what's going on :unsure:
> 
> View attachment 27117




ROFL! :lol: Classic!

BTW BribieG you have been one of my test subjects with Olive Oil. h34r: 

*Cue Evil Laugh Voice* BWAHAHAHAHA!


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## Spiesy (5/10/13)

thoughts?

http://www.ebay.com.au/itm/Wort-Aerator-Air-Pump-kit-For-the-Home-Brew-Hobbyist-/321217997763?_trksid=p2054897.l4275


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## djar007 (5/10/13)

I have one with a stone and two speed pump you can have for twenty bucks if you like. I have the benzo type now.


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## lael (5/10/13)

Benzo type?


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## brewtas (5/10/13)

These ones


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## bullsneck (5/10/13)

I think he means this...




edit - beaten to it!


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## lael (5/10/13)

ah cool. reckon there is much difference in your ferments?


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## djar007 (5/10/13)

Yeah those are the ones. I cant really say as for the fermentation. But I have read and read about the saturation levels not getting high enough with just a shake and also with a pond pump. I brew ales generally so it is not as much of an issue for me as the average lager brewer. But the ferments are quick and busy and it certainly isnt hurting. It does add to the cost a bit as the bottles at masters are thirty dollars and I seem to go through the o2 pretty quickly. But I dont mind wearing that cost to help my yeast stay healthy. But the aquarium pump worked great too and I was getting a great ferment using it too.


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## Spiesy (24/10/13)

Torn a little between these two aeration kits:

Mark's Home Brew $175.
PRO's: looks to be a better build quality. O2 by volume is cheap. 
CON's: expensive. 0.2 micron stone (have read 0.5 is better?). Replacement O2 not as easy to come by.

Conor Breware $111.
PRO's: cheaper. 0.5 micron stone. Easy to find replacement cylinders (Masters, Bunnings).
CON's: O2 by volume is more expensive. Doesn't have a gauge. Attaching regulator can result in issues.

Not sure on freight costs between the two.

Can anyone more knowledgable than I, in the art of aeration (i.e. all of you), shed any light and/or make any recommendations?


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## Black n Tan (24/10/13)

I have the connor brew are set-up and like it. It is my understanding that a 0.5micron stone is best for oxygen and 2 micron best with air. The Mark's HB is a 2 micron stone (not 0.2 micron).


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## Spiesy (24/10/13)

Black n Tan said:


> I have the connor brew are set-up and like it. It is my understanding that a 0.5micron stone is best for oxygen and 2 micron best with air. The Mark's HB is a 2 micron stone (not 0.2 micron).


Aah, yes - 0.5 v 2 micron - thanks.


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## Black n Tan (24/10/13)

I added an oxygen flow meter to the connor breware system so I could more accurately dose the oxygen and because I was going through oxygen canisters quicker than I had calculated I should be. It will pay for itself by ensuring you are not using more oxygen than you need. 
http://www.ebay.com/itm/LZQ-2-0-3LPM-Oxygen-flow-meter-with-control-valve-for-Oxygen-conectrator-/231014442738?ssPageName=ADME:X:AAQ:US:1123


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## Spiesy (25/10/13)

I would have thought more people oxygenated their wort round here... 
:beerdrink:


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## wbosher (25/10/13)

I just syphon from my pot into my fermenter from a height of 40-50cm or so, then give it a good thrashing with my mash paddle. But I use dry yeast which I hear doesn't need so much aeration.


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## Spiesy (25/10/13)

thanks, wbosher.

I have ordered the Conor Breware device.


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## Camo6 (25/10/13)

I've got a Connor breware setup. Very happy with it. One bottle probably lasted 7-10 brews ( records aren't my strongpoint). Swapped the gas line for some silicone aquarium hose so it sinks better, though I see he has an upgraded kit now. I used a texta to mark the optimum flow rate on the reg being that it has no flowmeter ( I like B&T's idea). I ran out of o2 recently and have definitely noticed an increase in fermentation times since resorting to the old paint stirrer.
I'd love to get my hands on a medical grade O2 bottle but I wasn't an AG brewer back when I was servicing ambulances. :angry:


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## Alex.Tas (26/10/13)

Could you use a sterilised whisk and beat the hell out of it for a while once its in the FV?


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## Camo6 (26/10/13)

That's all I did before buying an O2 kit. Works fine and gets adequate oxygenation just not the optimum O2 PPM that aids yeast health and growth.


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## Spiesy (26/10/13)

Camo6 said:


> I've got a Connor breware setup. Very happy with it. One bottle probably lasted 7-10 brews ( records aren't my strongpoint). Swapped the gas line for some silicone aquarium hose so it sinks better, though I see he has an upgraded kit now. I used a texta to mark the optimum flow rate on the reg being that it has no flowmeter ( I like B&T's idea). I ran out of o2 recently and have definitely noticed an increase in fermentation times since resorting to the old paint stirrer.
> I'd love to get my hands on a medical grade O2 bottle but I wasn't an AG brewer back when I was servicing ambulances. :angry:


7-10 brews doesn't seem like a hell of a lot. What's the bottle cost?


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## Black n Tan (26/10/13)

I bought 4 bottles from him for $100, so $25 each when yo buy 4.


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## Grainer (26/10/13)

I bout an oxygen bottle from Masters for about $28 and then they had a gas bottle conversion kit for about $25 (similar to that sold at connor .. just looks different) .. I will use the left over gas line or get some softer silicone stuff from work and then just need the difuser... So all up about $65.. BARGAIN !!

Hopefully a cheaper option all up.


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## Grainer (26/10/13)

Camo6 said:


> I've got a Connor breware setup. Very happy with it. One bottle probably lasted 7-10 brews ( records aren't my strongpoint). Swapped the gas line for some silicone aquarium hose so it sinks better, though I see he has an upgraded kit now. I used a texta to mark the optimum flow rate on the reg being that it has no flowmeter ( I like B&T's idea). I ran out of o2 recently and have definitely noticed an increase in fermentation times since resorting to the old paint stirrer.
> I'd love to get my hands on a medical grade O2 bottle but I wasn't an AG brewer back when I was servicing ambulances. :angry:


Masters has the oxygen bottles for about $28-29 Benzomatics


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## krausenhaus (26/10/13)

Grainer said:


> Masters has the oxygen bottles for about $28-29 Benzomatics


Yep, I got a replacement for about $30 at Masters the other day. I have done about 5-6 double batches from the first cannister, so 10-12 fermentors, and I think there's still a bit left. I lacky band my tube to a racking cane so I can get better control over it. Once it's in the wort, I adjust the reg down so that bubbles are just gently reaching the surface rather than foaming the hell out of it. Totally going to get one of those flow meters though.

I've noticed that some of my brews have finished a couple of points lower than expected since I started using it.


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## CONNOR BREWARE (27/10/13)

Grainer said:


> Masters has the oxygen bottles for about $28-29 Benzomatics


That's a good price. Last year when I started the business and selling the kits I tried to get something going with Masters. The best price they would give me was $28 for buying in lots of 20 and that was like pulling teeth. Good to see they are becoming a staple stocked item.

A tip is to do a special order through Bunnings and tell them the Masters price, they will beat it without to much fuss. May as well let the big boys retail fight work for us right?


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## Spiesy (28/10/13)

krausenhaus said:


> Yep, I got a replacement for about $30 at Masters the other day. I have done about 5-6 double batches from the first cannister, so 10-12 fermentors, and I think there's still a bit left. I lacky band my tube to a racking cane so I can get better control over it. Once it's in the wort, I adjust the reg down so that bubbles are just gently reaching the surface rather than foaming the hell out of it. Totally going to get one of those flow meters though.
> 
> I've noticed that some of my brews have finished a couple of points lower than expected since I started using it.


So around $3 a brew... that seems SUPER expensive for getting some O2 into your brew.


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## Judanero (28/10/13)

I got 11 brews out of the first bottle I used (was pretty happy go lucky with how much O2 I added into the wort), but I also used it for every starter. I haven't turned the reg so full on when I've used this bottle... marking the reg is a great idea!


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## Mardoo (29/10/13)

Judanero said:


> but I also used it for every starter.


How did you find your starters went? Been wondering about this myself. I just asked Kai at Braukaiser whether he's done any experimentation with this.


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## Judanero (29/10/13)

I've found all my starters too be more active, so they've really been hitting the ground running when pitched. I had all the components to make a stir plate but didn't knock one up before getting the O2, so I can't comment on the difference between using a stir plate and O2 injection. But between manually shaking and O2 injection, the O2 definitely = happier yea stirs IMO.


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## JasonP (29/10/13)

i know i am lazy and the answer is probably somewhere in this thread, but without me having to read all of it can someone tell me how long you have the O2 bubbling in the wort for (20L batches) ?


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## Black n Tan (29/10/13)

1 minute at 1 Litre/minute or if you don't have a flow meter, turned up enough that you can see bubbles but hey don't break the surface (so you don't waste oxygen).


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## JasonP (29/10/13)

Black n Tan said:


> 1 minute at 1 Litre/minute or if you don't have a flow meter, turned up enough that you can see bubbles but hey don't break the surface (so you don't waste oxygen).


Thanks B n T.


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## citizensnips (30/10/13)

Just a question hopefully without derailing the thread..........does anyone know how the big breweries take care of the aerating the wort problem?


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## doon (30/10/13)

An in line aerator as wort is transferred to fermenter. Someone could probably explain it better then me


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## Edak (30/10/13)

I wonder whether one could run their wort from kettle through one of those wine aerators into the fermenter. Would that help much?


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## Grainer (4/11/13)

Aeration project1 complete.

Stainless tube $2.50 (70cm) from Geordi Stainless steel around the corner... beer line had 30m spare... john guest fitting & airstone from craft brewer (screwed fittings) and valve for mini O2 tank from Masters about $25. This is a good start easy to sanitise and I prefer using the stainless than tube and the JG fitting and airstone can be easily removed to soak. I also have a small ebay valve control coming to regulate the airflow from the O2 canister (was pretty cheap from china). Note: Aeration stone not connected in this photo...

Bargain...

Next project direct line infusion after wort passes through the chiller....


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## Glot (5/12/13)

Has anyone tried an oxygen concentrator?
What about using sterilised air?


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## QldKev (5/12/13)

Aquarium air pumps have been used heaps, you can get a little sanitary filter to go inline to keep the air cleaner.


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## Droopy (5/12/13)

All I do is pour the water in - never had a problem with aeration


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## Glot (6/12/13)

Okay. So why go to Oxy with all the added costs?
BTW. I have been told by someone in the field that the purity standard for industrial oxy is higher than medical oxy. Makes sense. However, you never know what may have got into an industrial cylinder between refills.


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## Edak (7/12/13)

Isn't medical oxygen 5% co2? As pure oxygen has a habit of killing people, since our natural drive to breathe is directly related to how much co2 we inspire. No co2 no drive to breathe...


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## Midnight Brew (7/12/13)

Glot said:


> Okay. So why go to Oxy with all the added costs?
> BTW. I have been told by someone in the field that the purity standard for industrial oxy is higher than medical oxy. Makes sense. However, you never know what may have got into an industrial cylinder between refills.


I doubt anything would get in and if it did being the purity of 100% oxygen, I doubt it would survive.


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## Spiesy (7/12/13)

Droopy said:


> All I do is pour the water in - never had a problem with aeration


I think you have bigger problems than aeration if you're pouring *water* in.


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## Spiesy (7/12/13)

Glot said:


> Okay. So why go to Oxy with all the added costs?


Why *oxygen*ating wort, using pure *oxygen* makes pretty good sense to me.

It is pricey, you're right - but as they say... _homebrewing is an expensive way to make cheap beer_.


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## Glot (7/12/13)

I think sanitization is a bit like the 90 year old smoker that says I have smoked all my life so therefore smoking is not hazardous.
Poor sanitization practices does not mean you WILL get an off beer. It means you MAY. I have made a number of batches were I just ran the laundry tap water straight into the fermenter from a height. It worked but more by luck than design. With good sanitisation, it means the odds are very low. Also, note the difference between sanitizing and sterilizing.


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## Spiesy (7/12/13)

Glot said:


> I think sanitization is a bit like the 90 year old smoker that says I have smoked all my life so therefore smoking is not hazardous.
> Poor sanitization practices does not mean you WILL get an off beer. It means you MAY.



Why take the risk? It's really not that hard to maintain adequate levels of sanitation.


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## Edak (7/12/13)

I think you have bigger problems than aeration if you're pouring water in. 
not if he is an extract brewer topping it up to volume...


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## Glot (20/12/13)

Okay. Getting away from the yeastology part and more onto the practical side.
Difference between modern industrial oxy, medical oxy and aviation oxy. Apart from the price, all the same stuff. Early days was a different story. The difference between industrial and medical is the way the cylinders are filled. It is possible to get acetone into an industrial cylinder from an oxy acetylene set. The cylinder is tested for this before filling. To fill medical, they evacuate the cylinder first. Aviation oxy is dryer to reduce possible freezing issues at high altitudes.
An earlier post of using a 2 mic diffuser for air and a 0.5 for oxy. Any clues as to the theory behind this? What about the 0.2 mic diffusers? A 0.2 would also act as a filter for a lot of bacteria.
Any figures on litres per minute to get a good flow rate?


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## Midnight Brew (21/12/13)

Glot said:


> Any figures on litres per minute to get a good flow rate?


In the Yeast book by Chris White and Jamil Zainasheff the flow rate of 1L per minute is recommended using a micron sintered stone between 60-120 seconds. Which gets you between 9-14 ppm. (page 79) However what is 1L per minute if you dont have a reg?

Its best to use a few identical batches and record what you are doing and note the fermentation performance or taste differences.

I dont do this as I think my beer is fine buts its been playing on my mind in terms of consistency. There is a lot of factors at play.

I get the estimated attenuation since switching to using oxygen and the fermentation performance has been better overall. My crops of yeast have performed better on the next beer too so overall when my yeast is happy Im happy. Takes a tad more guess work out of it for me and I am happy with the beer I'm making.

My 2 cents, and a great book to have in your collection.


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## Glot (21/12/13)

I know there are a lot of variables but I was just after some sort of idea. Thanks. I have read litre of oxy gas per litre of wort for one minute. A simple flow regulator would be essential I thought unless you were just going off sight/ bubbles.


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