To simultaneously finish up both the outer surface and the inside of frozen food by equipping a temperature controller and a near/far-infrared heater with a specific wavelength at the upper portion of a toasting net, and energizing the near-infrared heater continuously and the far-infrared heater intermittently in conduction.
When an object 10 to be cooked of frozen food is placed on a toasting net 7 and a switch 13 is switched for energizing a near-infrared upper heater 4, a far-infrared upper heater 5, and a far-infrared lower heater 6, the near-infrared heater 4 with a radiation peak at a band with a wavelength of 1.5 μm or less is continuously energized. Radiation heat to be discharged reaches the inside of the object 10 to be cooked and increases its internal temperature. Radiation heat being discharged from the far-infrared heaters 5 and 6 with a wavelength of 1.5 μm or more reaches the outer surface of the object 10 to be cooked such as bread that is energized and frozen intermittently via a temperature controller 11 and a timer and burns the outer surface. The best timing for eating can be determined when the outer surface of the object 10 to be cooked is burned appropriately when viewed from an observation window 8 since the inside of the object 10 to be cooked is heated appropriately.
MATSUO HIROSHI
KUBO YOSHINOBU
ONO ATSUNOBU
