SCIENTIFIC SODA "POP" BOB QUESTIONS

[SODAPOPBOB]

I have read where the term "Pop" originated. But what I can't figure out is the following ...

Have you ever wondered why it is that soon after a carbonated beverage is opened that it goes flat in a relatively short period of time? I have wondered this too. In fact, this question of mine goes back at least twenty years when I did some experiments to see if I could figure out a way to seal an opened bottle of soda pop to prevent this from happening. I tried everything from new-fangled closure devices to melted paraffin wax. But nothing worked. Eventually all of my trials failed and the beverages lost pressure and went flat. Why?

Just recently I came across a commemorative Coca Cola bottle from 1994 that was still capped. When I opened it, it was still fully pressurized and foamed up nicely when I poured it into a ice filled glass. It had been sealed for seventeen years. And yet, based on past experiments, I already know if I attempt to reseal it, it will eventually go flat, guaranteed. Why?

I am not a rocket scientist, so I may never find the answer I am looking for. I have even done some extensive research on this subject, but as yet I have not found a plausible explanation for this so called phenomenon. Perhaps you have the answer?

Another aspect of this pertains to the newer plastic bottles with screw-off caps. I have also experimented with those and discovered that the “tamper proof†ring below the cap has nothing to do with how tightly the cap is set in place. It is simply there for an indicator to let us know if the cap has been opened and/or tampered with. Cut one of the rings off sometime and you will notice how it is designed with gripper-teeth on the inside that allows it to break free from the cap when you open the bottle. But even these I have experimented with and no matter how tight I reseal it, the contents still go flat after a time. Why?

So exactly what happens to an opened bottle of pop once air hits it? Any why does it eventually go flat no matter what you do to reseal it?

If you have a logical, “scientific†answer to this, I sure would love to hear it. Inquiring minds want to know.

To summarize: I have two basic questions …

1. How long will a sealed carbonated beverage remain pressurized? 17 years? 57 years? Longer?

2. What causes it to eventually go flat even if the bottle is resealed immediately?

Opinions and guesses are welcomed. But a scientific explanation is really what I am hoping for.

Thanks,

SODA “PONDERING†BOB []

 

[bostaurus]

The carbonation is caused by forcing CO2 into the liquid. Under normal pressure the liquid would only absorb a certain amount. By adding pressure they force more gas into the liquid. Then they stick a cap on it. some of the gas escapes into the little bit of air space left in the bottle which pressurizes the bottle and keeps more gas from escaping. Once you open the bottle the pressure normalizes and the gas eventually escapes because the liquid can't hold it under regular atmospheric pressure. To keep it from going flat you would have to pressurize the bottle again. If you drink half and then put the cap on the gas will still escape into the empty space you created when you drank some the soda.
There is a diving and getting the bends analogy but I don't know enough about diving to go there.

 

[SODAPOPBOB]

bostaurus ~

Right on! That makes logical, scientific sense. Can you expound a little on how the "forcing" of CO2 into the liquid, and "pressurizing" the bottle is achieved? Or perhaps a website link that explains it? If not, I will go back to Google and see what I can find. I am feeling lazy today and my non-scientific brain isn't working all that well. Lol []

By the way ... are those your words, or copy/pasted? I really like the way it is constructed, formated and explained. Good job!

Another by the way ... I see you are not a new member. But I don't recognize your name either. Where on Antique-Bottles.net do you hang out most of the time?

Thanks a lot.

Bob

 

[bostaurus]

Thanks, it was all me but not sure if I got it all completely correct, I think so. I was in the sciences before my kids came along and that was a long time ago. I think sometimes folks over explain concepts when all a person wants to know is a simple answer. My husband is still in science. Sometimes I may say, "What is that?". Half an hour later we are still on prions and tissue necrosis factors.
I got this off the web:
Carbon dioxide gas gives the beverage its sparkle and tangy taste and prevents spoilage. While it has not been conclusively proved that carbonation offers a direct medical benefit, carbonated beverages are used to alleviate postoperative nausea when no other food can be tolerated, as well as to ensure adequate liquid intake.

Carbon dioxide is supplied to the soft drink manufacturer in either solid form (Dry Ice) or liquid form maintained under approximately 1,200 pounds per square inch (84 kilograms per square centimetre) pressure in heavy steel containers. Lightweight steel containers are used when the liquid carbon dioxide is held under refrigeration. In that case, the internal pressure is about 325 pounds per square inch.

Carbonation (of either the water or the finished beverage mixture) is effected by chilling the liquid and cascading it in thin layers over a series of plates in an enclosure containing carbon dioxide gas under pressure. The amount of gas the water will absorb increases as the pressure is increased and the temperature is decreased.


I hang out here and there. Sometimes sticking my nose in where it shouldn't be. It is a fun forum and I have learned quite a bit.

 

[SODAPOPBOB]

Bo ~

supercalifragilisticexpialidocious !!! Thanks again. That pretty much answers question #1. I actually understand it thanks to your simple explanation that a simple-minded guy like me can comprehend. You should "pop up" here more often. I really enjoyed and appreciate your contribution.

But question #2 may be a little more difficult to answer, and may require someone to open up one of their still-capped 1950s soda pop bottles to see if it is still pressurized and carbonated. Are there any volunteers among us or anyone who has already done this in the past? My oldest capped bottle has a slightly rusted cap and the carbonation is long gone. I believe some champagnes remain "fizzy" for about a hundred years or more. ???

What say y'all?

SPBOB

 

[bostaurus]

There are so many threads on the forum that I usually skip the sodas. I collect veterinary meds and some apothecary bottles. I don't think I have ever had a soda bottle except a couple old cokes. Until I joined the forum I did not realize the all the different types, ages and styles.

In theory, if the bottle is well capped and sealed, the carbonation should stay "fizzy". It would only go flat if the CO2 could escape so over the years. If the seal loosens or dries out, it would go flat.

 

[Wheelah23]

I've got a sealed Dr. Pepper from 1973, and a couple sealed cokes from 1983 and 84... One from 1993 too, which I was going to recycle.

 

[SODAPOPBOB]

Wheelah23 ~

Right on! "POP" goes the weasel! Let us know if you open one and if it's still carbonated. I didn't drink mine and don't recommend it. []

SPBOB

 

[Anthonicia]

If Wheelah doesnt open his then I guess I can open up a '76 7 Up Commemorative Bi-Centennial bottle. There are plenty of those around and I doubt opening it affects the value of it at all.

So if the build-up of gas hold the carbonation in, wouldn't shaking it up help keep it carbonated? I have tried shaking the 2 liter after pouring my drink and putting the cap back on, but I can't really tell if it works to save carbonation.

 

[SODAPOPBOB]

Ant ~

Thanks for stopping by. Let us know if you "popper" open. Regarding carbonation: I'm convinced it's like bostaurus said and it needs to be re-pressurized to maintain. Maybe if you poked a hole in the plastic liter bottle and pressurized it with a bike tire pump it would work. But then you would have to deal with some way of quickly sealing the needle hole. It's a vicious cycle ... or should I say "bicycle?" Lol []

SPBOB