Wort Aeration

[neonmeate]

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."

 

[kirem]

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.

 

[Darren]

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

 

[kirem]

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.

 

[RussTaylor]

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...

 

[Bribie G]

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.

 

[neonmeate]

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...

 

[kirem]

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

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

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.

 

[neonmeate]

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?

 

[katzke]

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.

 

[jonocarroll]

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

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.

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.

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.

 

[Adamt]

The answers to your stir-plate questions:

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

 

[muckanic]

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.

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.

 

[Bribie G]

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.

 

[jonocarroll]

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:

 

[Kai]

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

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.

 

[suorama]

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.

 

[chappo1970]

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

 

[Bribie G]

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.

 

[JonnyAnchovy]

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!