Magical Energy Drinks

A few days ago, I placed a Monster Energy drink into the freezer in an attempt to get it cold during the 30 minutes or so it took for me to get ready to go out. Unfortunately, I totally forgot about and there it stayed for days. As is always the case with canned beverages left in the freezer, it expanded as it froze and exploded leaving pink slush all over the shelf it was on; something I discovered when I opened the freezer earlier today.

I took out the can and placed it by the sink as I cleaned the freezer. After a while, when what remained in the can melted, I proceeded to pour it into the sink. Funny thing is that when I was pouring it, the liquid was green. It was pink when frozen; green when a liquid.

I wonder what color it is when it's a gas?