Ever since I read this article
http://blogs.westword.com/cafesociety/2008/11/geek_in_the_galley.php
I have been researching a food technology fantasy of mine. Floating food. My first thought was superconductivity. I wanted to find a food that was naturally high in metal. Would the small traces like Mercury in tuna be enough to hold the food up in a magnetic field? I then found out that a rare earth magnet is really what levitates. My thoughts of floating tuna or building a hallow metal container that would float and could be opened up to reveal a dish were out. Another down fall to the superconductivity dish is rare earth metals cannot be heated. They release harmful toxins that can kill you. The only option with superconductivity is to use the magnet as a cold "plate". After doing a little more research I came across Sulfur hexafluoride. This is a colorless odorless non-toxic gas.What makes it so interesting is that when you fill a glass with sulfur hexafluoride the molecules are so large that air will float on it. What does this mean? If you made a air texture which we can do with lecithin or egg white powder, it would sit on top of the gas in the glass and have the illusion of it levitating. The problem- it is very expensive and is the most potent of the green house gasses. Next time a get a little time in a lab I will test my theory.