carbonation in warm vs. cold club soda

At a BBQ at my house Sunday night a friend claimed that chilling carbonated drinks decreases their carbonation. He swears that chilling club soda “ruins” it- and claims to know this by the quantity of scotch and sodas he’s consumed through the years. I claim that the temperature should not alter the carbonation at all, that a proper seal would prevent this. Who’s right? Any information on how heat affects carbonation would be helpful. And how does heat affect carbonation once the can/bottle has been opened?

I trust that your friends scotch-and-soda habit has effectively killed his chemistry knowledge, and so I will handle this and set you straight.

Solubility is temperature dependent. In almost every case, the solubility(amount of stuff that will dissolve) of solids in water increases with temperature, while the solubility of gases in water decreases with temperature. What this means is that you will get more salt to dissolve in 90[sup]O[/sup] C water than in 5[sup]O[/sup]C water, but you will get more carbon dioxide to dissolve in the 5[sup]O[/sup] water than in the 90[sup]O[/sup] water. Since more CO[sub]2[/sub] will dissolve in cold water, warm club soda will lose its carbonation faster than cold club soda. If you wish, you can prove this to yourself by keeping identical quantities of fresh club soda at different temperatures and count the bubbles at regular time intervals to see which is more or less carbonated. I guarantee you that you will get the results I outline above.

Now, the other issue is flavor. Generally, warmer things tend to produce more intense flavors than colder things do. Its why certain varieties of beer are supposed to be consumed warm, because cold effectively “kills the flavor.” If something has too intense of a flavor, you want to have it cold. If you want to bring out the intensity, consume it warm. It may be very true that your friend prefers the taste of his scotch-and-soda when it is warm, but it has nothing to do with the levels of carbonation, since his warm club soda is losing carbonation faster than his cold club soda.

E Bailey, Welcome to SDMB.

There’s not much to add to Jayron’s eloquent post but to say that if the bottle is not opened, the CO2 can’t escape regardless of temperature (unless the temp gets so high that the CO2 coming out of solution raises the pressure in the bottle high enough to blow the lid off).

Jayron, I have spent hours(though not today) looking for a CO2 in water temperature/solubility curve. Do you have any good leads?

Possibly more bubbles are formed in a warm bottle when opened than in a cold bottle, allowing the carbonation to escape faster.

Can cold temperatures suppress nucleation sites? Cecil doesn’t say for sure in ‘Return of the Straight Dope’ or 'Triumph of the straight dope, but one might suppose that cold temperatures slow the molecules down a bit.

Thank you for your swift and clear response, jayron 32. I sent it to my friend, who replied with this:

“Oh you had to go there again. First thing, I know why they call it the Straight Dope, it’s the type they use. I never said that carbonated beverages lose more carbonation in the fridge as opposed to room temperature. I said that an opened, re-sealed bottle will lose it’s carbonation faster in the fridge than at room temperature. Didn’t you take
any science or physics labs in school? It has to do with the integrity of the seal. I know you hate to be wrong, however, take two bottles, open them and pour a little out. Re-cap the bottles and put one in the fridge and leave one on the counter. After two days test them and see which is more carbonated. You will then see the light my child.”

Any response I can give (other than point out the fact that I have a liberal arts college education that may not have provided me with a lot of chemistry but I can beat the crap out of anyone at Jeopardy!)?

I have no idea what a 15[sup]O[/sup]C difference is going to have in the integrity of the seal in a polypropylene cap on a polyethylene bottle. This sounds like total bullshit, and if you want to win some money from this guy, take him up on a bet and conduct the experiment. Once a bottle has been opened, the temperature effect on solubility will be more pronounced. Warmer soda will go flatter faster. I would even bankroll a modest (<$10.00) bet for you on this one I am so confident.

E & Jay, Yes, but how are you going to test them? If you take two bottles, presumably at the same temperature, open them, pour some out, and reseal them, they should still have the same amount of CO2 in them. Put one in the fridge, and fast-forward two hours…

Let me guess, shake 'em both up and open 'em. The one that fizzes most wins. I vote for the warmer one.

E., your friend is messing with you.

PS, Don’t worry about those hiccups, it just means she’s growing.

Actually, for the test to be fair, the bottles need to be at the same temperature before you check for bubbles… the colder bottle will have it’s CO[sub]2[/sub] release suppressed by the fact that it is colder, even if it has more carbon dioxide. Here’s my protocol for the experiment:
Equipment:

3 2-liter bottles of club soda
3 small thermometers, small enough to fit inside of the bottles and which can be read (red alcohol-type thermometers should be fine for our experiment)
a refrigerator, an oven, and a countertop.
3 stopwatches
3 small bottles (16 oz soda bottle should work)
3 large balloons

Procedure:

The idea here is that we need more than just 2 data points. Three is a bit better, though ideally we would have dozens of samples of club soda at dozens of temperatures. Leave three bottles of club soda out for a few hours at the same temperature. Open each, and pour the same amount out of each bottle. Put a thermometer in each, and recap it. As soon as you recap them, start one of the stop watches. Put one bottle in the fridge, one in the oven at the lowest temperature setting (most ovens have a 150[sup]O[/sup]F setting, well below the boiling point) on a cookie sheet, and leave one on the counter top. You should try to have each standing upright and undisturbed for the whole experiment if possible. Check and record the temperature at regular intervals, and wait for the temperature in each bottle to plateau. Keep each bottle at the equilibrium temperature for 8 hours(try to be precise about this). Remove the bottles from the fridge and oven, and allow each to return to room temperature. Now, once each has returned to room temperature, we should test each for carbonation. Pour 2 ounces* of soda into each of the three smaller bottles and IMMEDIATELY put a balloon on each one after pouring. Shake each bottle gently, and measure the circumference of each balloon once evolution of carbon dioxide has ceased.

  • The amount of soda you use is uncertain here. You want enough to give you meaningful results (i.e. inflate the balloon enough to measure) while not being so much as to FULLY inflate the balloon, thus ruining the experiment. Some trial and error testing should be done to determine the ideal amount to use for testing before the actual experiment is done. The important thing, however, is to use the EXACT same amount of club soda in each experiment.

The idea here is that you want to test each bottle of club soda at the same temperature, since you want to eliminate the notion that the rate of release of carbon dioxide and the holding capacity of the soda WILL vary with temperature.

WAG: I suspect that your friend is noticing that he detects more carbonation is released from his drink when he uses warm club soda than when he uses cold. This is consistent with the idea that cold club soda loses its carbonation SLOWER. Since it is cold, it fizzes less, because it is hodling on to it’s carbon dioxide. Warm club soda will have a more intense fizz, but will go ‘flat’ faster. If he is consuming the club soda before it goes flat, the preception will be that warm club soda is fizzier. This is true only because it is releasing its carbon dioxide faster, and is the exact OPPOSITE reason than he is giving for using warm club soda.