Boiling oil in a Microwave?

Most recent answer: 09/28/2011

water boils in microwave oven but oil does not boil in microwave oven .why ?
- anusha (age 23)
secunderabad,andhra pradesh, india
Although I've never tried it, I guess if you kept oil in the micro-wave for a long enough time it would eventually boil. There are several reasons why oil is hard to boil. First of all, most cooking oils boil at around 250oC, much higher that water.   Secondly, micro-waves add energy to a system by means of dielectric heating.  Water, which has a large electric dipole moment, is very efficient at absorbing the microwave energy.  Most oils, however, have rather small dipole moments and don't absorb the radiation as much as water. 


p.s. Most cooking oils will start to smoke from chemical degradation before they boil.
Mike W.

(published on 09/28/2011)