Hi Luciano,
I am glad to see that you've been experimenting with different kinds of photography besides the travel and landscapes pictures we usually get to see from you ;-).
I like the idea, although the execution could have been a bit better. If you don't mind me saying so, here is my C&C:
1) Nice colours, nice glass and water/ice in the glass. Also the setting sun makes it feel good. Pity it is then that the lamp behind the glass totally disturbs the composition. If you'd have moved your camera just 30 cm to the left, I guess you could have taken an uncluttered picture.
2) Again, nice colours. I think that the left side is cropped too tight. A bit wider would be better, like in picture 3.
3) Composition wise, the best of the three. What I miss is some highlight on the glass to attract attention to it. And it is empty, which can be interpreted differently by some people.
All together, a very nice start. I'd suggest working on it a bit more to have some other variations. You can then compare and see what works and what doesn't.
Thanks for showing.
Cheers,