The short answer would be it depends if it is designed to.
There may be an interlink where the flex connects to the appliance which can be moved to bridge the phases, but if the fryers have been designed to only work on a 3 wire (plus earth) system using the voltage between phases, you would end up running it on single phase (line to neutral, 120v) which may cause it not to work, or even damage it.
Best thing to do is contact the manufacturer.
Adam
March 2010