Help me design my self-cooling soda/beer/drink containers

In My Humble Opinion
1

I bought some pop today and while I was grumbling to myself about waiting for it to cool I had what I’m sure is a brilliant idea. When they bottle the drink (or can it), if they pump enough gas in and pressurize it enough, when I open it and release the pressure, the drink will almost instantly cool.

I have lots of questions, and can see a lot of problems, but maybe we can at least figure out some general parameters.

Let’s just say we want to cool a 20 oz drink about 40 degrees (from an 80 degree ambient temp down to a 40 degree cooled drink).

How much pressure release do you need to lower the temp that much?

Since pressurizing it would heat it during bottling, how hot would the bottles get?

What would be a good gas to use? Can’t be flammable, or toxic. And I think we don’t want a gas that will mix into the fluid – I don’t know the right term here, but I don’t think we would want to simply increase the CO2. I’d guess that would simply result in a fluid explosion during opening. So I’d think we’d want a gas that would stay separate, and come out on its own when the seal is broken. Or maybe some means to moderate the depressurization could be found, so the fluid doesn’t explode out.

Any thoughts on this?

2

It’s been done, although I’ve yet to see it in a store.

3

Here’s a thought:

  • embed a gas canister inside the liquid
  • cracking the tab open will
    • (a) first, puncture the gas canister, which vents not into the liquid, but directly to the outside air
    • (b) second, open the container in the normal way, allowing access to the liquid

So, gas expands as it exits gas cylinder (into the atmosphere), cooling both it and the liquid surrounding it. You would still factory-carbonate the soda in the same way as now.

A more advanced option would be some sort of double-walled can (or honeycombed can wall?), with the cavity being filled with compressed gas (that is then vented to the outside in the same way). Or, most effective, an immersion coil filled with compressed gas. But I think both of those options will pose serious engineering difficulties to prevent accidental rupture.