Flat Soda? Not Anymore!





Introduction: Flat Soda? Not Anymore!

Save your soda from going flat. The last drink will be as good as the 1st, even with 2 or 3 liter drinks!



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After reading all the comments and instructions, it seems like it would be so much easier and cost effective to just throw out the flat soda and go buy a new one. It will be not only fully carbonated, but cold and refreshing as well.

I suggest getting a mini Co2 tire inflator (cartridges are pretty cheap each).
Use that instead of a compressor or pump (which will both just compress the bottle with atmospheric air, including dust and bacteria).
Using the cartridge will allow you to keep your soda/pop arguably more sterile, and additionally will re-carbonate with Co2 (regular AIR doesn't dissolve into liquids as readily).

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Also... many home-brew stores have this exact same item already made professionally.
Some are cheap/reasonable, some are expensive.
This though is a great how-to, in case you don't have a cost-effective homebrew store near you... ;-D

OKAY!!!! This doesnt work. For those of you who tried and got flat soda still, here is why. It deals with chemistry in the respect of Dalton's Law of Partial Pressures. Initially your soda comes with a certain amount of CO2 that is dissolved into the liquid soda. When you open the cap, some of that CO2 releases from the liquid into the atmosphere. You drink some, with some soda left. You cap it, and as the soda sits, the CO2 left within the liquid releases and fills in the space above and slightly pressurizes the system. Now the problem with adding just air is that air has different solubility properties than CO2, therefore you are simply pressurizing the volume of gas above the soda, not the soda itself. This is why it still is flat upon reopening the bottle. The only way you can recarbonate your soda is to completely remove all the air from the system when you recap the bottle, then add CO2 only. This will recarbonate the soda, although not to the extent that it is when you first buy it. As you add pressure to the system by adding gas, and only the one gas (CO2) is involved, the gas becomes more soluble in the liquid soda, thus carbonating it. Different gasses have different solubility properties. Air isnt the same as CO2. Thus this technique will not work.

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True, it won't recarbonate, but ANY pressure will help slow the loss of the Co2 that is already dissolved in the soda.
You're right though that using regular AIR isn't ideal. Best results would be to use a Co2 cartridge to pressurize it. (The same cartridges used for bike tires are used for portable beer Co2 systems.)

long time no coment, but i will use this $1 for 3 leader $5 for a 12 pack

I bought for about 3 bucks a cap with a pump and just screw it on and pump it. Does not taste like black butyl rubber, yeck. But it like this probably will make soda taste flat in the end. You are pumping a lot of non CO2 gas into the bottle, it permeates the soda and it still taste flat . What was nifty though was my friend (as a kid) did this to a water pistol and made a pressurized squirt gun before pump up water guns were made. He was a diabetic and used syringes. What a hoot.

Do you have to take the cap off before you pour or does the cola somehow go through the cap?

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I would venture to say take the lid off.

Good Idea I will have to try it some time.
  BTW I don't see all the fuss about the nails some people just naturally have fast growing strong nails. Jealousy is they only reason I can see for fussing about it.
 Of course having nails like that has its drawbacks as well, like breaking the nail clippers ( my husband has strong nails like this and has broken nail clippers before). anyways thank you for the instructable.

Mine tasted like rubber and didn't carbonate. Any tips?

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I made mine of the metal valve stem. I've never had a taste issue with it.

A rubber valve stem will not let you 'bolt' the tire stem to the cap. It would be aggrivating.

Any autoparts store

Mine doesn't have the washer or the nut. Is this okay?

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The washer you can do without... The nut is needed to screw the vavle stem to the top.