The glass looks like it is one solid lump. It needs walls. If you want to add alcohol as well, you will need to ensure that the alcohol does not touch the glass, otherwise weird artefacts will probably ensue. The simplest way of achieving that is by using the inner wall of the glass bottle for the alcohol.
The image below demonstrates what I mean. On the left is the complete bottle. In the middle, the bottom half of the bottle looks solid, since it has only an outer wall, and the top looks like a bottle since it has both outer and inner walls. To the right is the bottom half of the inner wall, which was separated from the bottle’s mesh, and has a different texture to make it simulate a drink. So the lower half of the bottle, which contains the “drink”, does not have an inner wall.