I don't know how the kids are doing it these days, but in my day we used acrylic resin (available by the bucket in larger craft shops) for "ice" and clear Krylon (misted with water from a plant mister when necessary) for "frost". Unlike food maquettes (such as using coloured Crisco and icing sugar for "ice cream") you aren't breaking any truth in advertising laws, and the "ice" will survive the lighting and staging process. Real ice poses a lot of problems. There is a relatively narrow range of temperatures in which it looks right (too cold and it lacks gloss, too warm and it melts too quickly), it takes textured fingerprints (or gloveprints) that you're forever having to torch out (while carefully trying to avoid soot deposits -- which can never be removed completely, and therefore mean starting over again). And in the end, the fake stuff usually looks more believable than the real.

I don't know how the kids are doing it these days, but in my day we used acrylic resin (available by the bucket in larger craft shops) for "ice" and clear Krylon (misted with water from a plant mister when necessary) for "frost". 

Unlike food maquettes (such as using coloured Crisco and icing sugar for "ice cream") you aren't breaking any truth in advertising laws, and the "ice" will survive the lighting and staging process. Real ice poses a lot of problems. There is a relatively narrow range of temperatures in which it looks right (too cold and it lacks gloss, too warm and it melts too quickly), it takes textured fingerprints (or gloveprints) that you're forever having to torch out (while carefully trying to avoid soot deposits -- which can never be removed completely, and therefore mean starting over again).

In the end, the fake stuff usually looks more believable than the real.