Is Soda Water Deoxygenated?

[MHB]

What stops the growth (reproductive) phase? Usually its running out of Oxygen in the brew.

Yeast doesnt want to make Alcohol; it wants to make Yeast, under adverse conditions it will switch over to alcohol production, to poison its neighbours so when conditions change (i.e. more O2 becomes available) it has more opportunity go back to making yeast.

We just subvert the process to get the yeast to do what we want, but yeast is always hungry for Oxygen.

MHB

 

[Thirsty Boy]

I shall avoid theory and go with practical -

At work where we make much of the sort of beer to which Asher refers.. we do our dilution with de-aerated water. The water is de-aerated in exactly the way Kai suggested, by bubbling through CO2 while venting the tank. At the end of the process the water basically has no dissolved O2 in it at all. The fact that the water is lightly carbonated afterward, means that the mild effervescence will stop any 02 pick-up during transfer.

Boiling it first would speed up the process and use less C02 as you would only need to drive out the small amount of oxygen that the water re-absorbed after it cooled down, and to add a light spritz so it wont pick up any more later.

TB

 

[James L]

Asher.

when i'm making anaerobic media at work, i tend to boil the media (usually 1L or 2 at a time), cover the bottle with foil, and bubble carbon dioxide through it for 20 minutes as it cools. If you dont do this, as the media cools, it will start absorbing oxygen again.

Then you can seal the bottle, and then purge the headspace with CO2 until needed.

Otherwise, if you have access to a sonicator, you can remove dissolved gas by sonicating under vaccuum but that is probably a little difficult...

Cheers

James.

 

[randyrob]

I'm thinking of having a play with this over the weekend.

i've got a keg full of 9.1% DIPA and i'm running out of general consumption beer
so was thinking of filtering and boiling 10L of water then running this into a C02 purged keg
then filling the headspace with more CO2 and chuck in the fridge and when cool transfer 10L
of DIPA into that keg, effectively ending up with 19-20L of 4.5% beer and 10L of 9.1% DIPA.
What do you think?

Rob.

 

[Doogiechap]

I'm thinking of having a play with this over the weekend.

i've got a keg full of 9.1% DIPA and i'm running out of general consumption beer
so was thinking of filtering and boiling 10L of water then running this into a C02 purged keg
then filling the headspace with more CO2 and chuck in the fridge and when cool transfer 10L
of DIPA into that keg, effectively ending up with 19-20L of 4.5% beer and 10L of 9.1% DIPA.
What do you think?

Rob.

Hey bloke,
Sounds like a plan .
Just try out the dilution ratio in a glass first with cheapo soda water to see what suits your tastebuds
Cheers
Doug

 

[Thirsty Boy]

What Doogie said, but remember that the cheapo soda water sometimes has (someone mentioned earlier...) bi-carbonate in it. Your beer will quite likely taste a little like... well, soda water.

A great idea to check the dilution ratios first, but I would go ahead and make your own soda water from filtered and boiled water instead of using the bottled stuff.

TB

 

[mika]

If you dont do this, as the media cools, it will start absorbing oxygen again.

How much oxygen are we talking here though ? I remember a post that Screwtop did where with a DO meter he measured the amount of dissolved oxygen in a wort sample prior to yeast pitching. Think it may have been quite a while after the boil and it registered 0 on the scale. He then went on to aerate with different methods and test how much oxygen and whatever was needed but not relevant here.
So thinking that the amount of oxygen picked up is probably negligble ?

Rob - I don't know if cooling boiled water in a closed vessel is such a good idea. Wasn't that the ol' science trick for crushing a can ? or is my brain completely addled :unsure:

 

[randyrob]

Rob - I don't know if cooling boiled water in a closed vessel is such a good idea. Wasn't that the ol' science trick for crushing a can ? or is my brain completely addled :unsure:

yeah i did think if this, but it's not an issue really my first handfull of ag batches were no-chilled into 19L cornies before i got a chiller.
the only thing to watch out for is if the ss touches your leg you end up with a bit less skin in that patch

 

[James L]

Mika, That protocol is for ensuring there is absolutlely no oxygen in the media. For those strict anaerobes. I'm sure you dont have to be that particular for this application, but it works...