Apparatus for cooking an egg using microwave radiation
The invention relates to an apparatus for boiling an egg, comprising a device for providing microwave radiation in a confined space, comprising a holder with at least one cavity adapted to the shape of an egg with an eggshell, said cavity provided with a first layer surrounding the eggshell, said first layer: —is in heat exchanging contact with the shell of the egg; —has a dielectric constant with an imaginary part, ε″, between 20-500 at a temperature between 0° C.-100° C. and at a microwave frequency of 2.45 GHz, and—having a layer thickness d of 1-6 millimeter and varying less than 30% over the egg, or said holder for holding at least one egg assembly adapted for cooking an egg using microwave radiation.
1. A method for cooking an egg with an eggshell, by means of an apparatus, comprising the steps of:
placing a hard-shelled egg in a first part of a holder;
closing the holder by means of a second part of the holder so that the hard-shelled egg is placed in an egg cavity defined by the parts of the holder;
the parts comprising inner surfaces adapted to the shape of the hard-shelled egg, the inner surfaces follow the contour of the shell of the hard-shelled egg in the egg cavity at a distance thereof of 1-6 millimeter, the distance varies less than 30% over the contour of the shell of the hard-shelled egg and defines a space between the hard-shelled egg in the egg cavity and the inner surfaces of the parts;
filling the space between the hard-shelled egg and the inner surfaces of the parts with a liquid through a filling opening in at least one of the parts,
the liquid forming a packaging surrounding the hard-shelled egg, which packaging comprises a layer being in heat exchanging contact with the shell of the hard-shelled egg and has a dielectric constant with an imaginary part, ε″, between 20-300 at a temperature between 20° Celsius and 100° Celsius and at a microwave frequency of 2.45 GHz;
said layer has a combination of a layer thickness d and the imaginary part ε″ of the dielectric constant selected from the area bounded by the curves: ε″(d)=229·d −1.168 , ε″(d)=2989·d −2.237 and ε″(d)=300 for an egg of between 45 and 75 gr, allowing the hard-shelled egg to become a cooked egg in less than about 120 seconds when subjected to microwave radiation;
providing the microwave radiation in a confined space in which the holder is mounted;
cooking the hard-shelled egg.
2. A method according to claim 1 , comprising the steps of:
determining a weight of the hard-shelled egg;
based on the weight and based on the layer properties and a desired cooking grade of the hard-shelled egg, determining cooking parameters based upon microwave energy and a cooking time;
subjecting the enclosed hard-shelled egg to the microwave radiation;
determining during the cooking, a temperature of the hard-shelled egg at various moments;
adjusting the cooking time or an energy of the microwave based upon the determined temperature values.