Patent ID: 7191698

Claim:
An apparatus for monitoring the degree of doneness of food comprising: a vessel, which, in use, contains a fluid and a quantity of food disposed in the fluid; means for heating said fluid to cook said food; first and second ultrasonic transducers acoustically associated with said vessel wherein ultrasonic signals transmitted by said first ultrasonic transducer pass through at least a portion of said fluid and said food and are then received by said second ultrasonic transducer; and a processing device operable to receive an output from said second ultrasonic transducer representative of said signal received by said second ultrasonic transducer, wherein said output exhibits at least one transmission characteristic of said received signal which varies as a function of the doneness of said food; wherein the processing device is further operable to determine a first value corresponding to the doneness of said food from the received output and a value corresponding to an ultrasonic characteristic of the fluid.