[lynn71]

I have been experimenting with making my own gelatin shots with alcohol .  Starting with gelatin and adding different flavours and colours.  I was using a 1%w/v gelatin mixture and 20% vodka and then adding different colours and or flavours.  I was hoping someone could explain the chemistry of how gelatin and alcohol solidify in addition to why sometimes the mixture will return to its liquid state after a few hours at room temperature.  Sometimes this happens but I do not understand why?? 
I was thinking it might have to do with the temperature i heat the initial gelatin mixture, or maybe the pH.  I could of course just increase the level of gelatin to ensure it would not go back to liquid state but this results piqued my curiosity as to what reactions are happening behind the scenes.
I would love if someone could explain what chemistry of above.

[vmelkon]

It is probably a heterogenous mixture.
I haven't experimented with this stuff but my guess is that the amount of gelatin added has an effect on how stable it is. Perhaps if you don't have enough, some of the alcohol/water leaks out.

[billnotgatez]

WIKI has a nice discussion
http://en.wikipedia.org/wiki/Gelatin