[Sca-cooks] use of soda bottles for storage

[Stefan li Rous]

'Lainie replied to me with:
> I don't think it's as much of a problem as you are thinking, Stefan.  
> I've
> done small mead in plastic- it's fizzy and I haven't had a problem with
> it.
But how long are you keeping this small mead? On the order of a few 
weeks or months, right? Not the one, two or five years that most meads 
are kept. Actually I'd forgotten about small meads earlier and was 
thinking of regular meads, either bubbly or not. That is all I've ever 
made.
> Remember- soda pop doesn't lose it's fizz unless it's been opened.
Nope. I'm talking about bottles, either glass or plastic, which have 
never been opened. You then twist/fight the top off, but no "pop" and 
no fizz.
> It is the introduction of air that does it. The more air in the 
> bottle, the
> quicker it goes flat.
No. It is the reduction of pressure in the bottle. We're talking about 
the fizz going away, not the beverage going bad or turning to vinegar. 
The latter would be caused by the extra air or more precisely the extra 
beasties introduced.
> And it seems to also be surface area exposed to  air-
> quickest way I know to make a half bottle of soda to go flat is to lay
> it on it's side.
Because initially when recapped, the air is going to be at about one 
atmosphere. The CO2 in the soft drink will then more easily exit the 
soft drink into the air in the bottle because the pressure of the air 
in the bottle is less. Once the air is pressurized enough, the CO2 in 
the soft drink quits leaving.  When the bottle is full the amount of 
CO2 needed from the beverage to pressurize the air in the bottle  isn't 
enough to notice. As the bottle gets emptier, more CO2 is needed from 
the beverage to pressurize the air in the bottle and the beverage seems 
"flatter".

I don't think the increase or decrease in surface area affects how 
"flat" the soft drink gets. It may affect how quickly the air in the 
bottle and CO2 remaining in the liquid reach equilibrium, though. Just 
the total volume of the air pocket that needs to get pressurized 
effects how much of the CO2 goes to pressurize the air and how much is 
left in the soda. Well, the temperature also affects this, but let's 
assume the temperature is the same in all these cases.

They do sell little pumps which can be used on opened bottles to 
pressurize the air in the bottle with the idea of keeping the CO2 
dissolved in the soft drink.

Stefan
--------
THLord Stefan li Rous    Barony of Bryn Gwlad    Kingdom of Ansteorra
    Mark S. Harris           Austin, Texas          
StefanliRous at austin.rr.com
**** See Stefan's Florilegium files at:  http://www.florilegium.org ****