OK, it looks like the large black label was on the front as part of the labeling, even when I looked at the file and edited it. Strange, I didn't even see after the emails? It was that back sticker at the bottom that I (and others maybe) thought was the issue.
There isn't anything that can be done unless you light the liquid from the inside out with a dark background so no light is coming from back to front. There is nothing that can be done with photoshop's either, not reasonably or to show a true representation. You have to overpower that label in the back, but since you need a white background, and you want the liquid to look like its natural lighting state, you have a seemingly impossible task.
If there is a way to either, I would think suggestions would have come forward, but the requirements make it nearly impossible to do this.
You may have to shoot with a black background and then edit that to white afterwards but that would take some time to make it look right using a bit of masking. What is the largest viewing resolution for the customers on the site? That is easier photoshopping than cloning out labels though.