You're absolutely right about the stomach. That is definitely not hunger.
I was there, at day 48... it was a very unusual sensation having nothing to do with either the stomach or with hunger. It was, as I say, a heaviness in the solar plexus that no amount of lemonade would fill. A very peculiar sensation indeed.
That fast was supervised by my excellent naturopath, who had me go to fresh juices. I had amazing energy on to day 60! Wow.
I had a couple of detox crises during that fast that virtually turned my health around. It was a lot of work, but so well worth the effort.