I don't know for sure either way, and can't think of an experimental way to check off hand. I don't think that heating is likely to do anything to the other components of most drinks, and you might be able to make a better guess with domain knowledge I don't have.

I think ethanol will generally evaporate more quickly than water, so you might also be able to get a similar test by simply closing one portion into a container with only a little air, and leaving another open for a long enough time, overnight maybe. will still lose some water, which is I guess a more real problem with heating as well.

shrug, the details weren't really the point, just wanted to emphasize the idea of thinking of ways to test whatever you're interested in physically instead of just reasoning about it.