Toaster using infrared heating for reduced toasting time
View Patent ↗A toaster uses radiant heat at infrared wavelengths optimized for producing rapid and uniform toasting of a food product. The infrared wavelengths of the radiated heat are selected for optimum speed and quality (browning and moisture content) of the food product. The selected infrared wavelengths of the radiated heat may also effectively defrost a food product. Defrosting of the food product by the infrared radiated heat adds very little time in obtaining a desired toast color to the food product. A plurality of infrared wavelengths of radiated heat may also be used, wherein the plurality of infrared wavelengths are selected for optimal heat penetration and surface browning of the food product. Shorter wavelengths for browning and slightly longer wavelengths to penetrate the food product for evaporating the moisture therein to allow surface browning by the shorter wavelengths. In addition, the heating energy within the toaster may be further elongated (longer wavelengths) once the infrared radiation is re-radiated off of reflectors within the toaster. The wavelengths of infrared radiated heat may be from about 1 to about 3 microns, and preferably from about 1.96 to about 2.5 microns, and most preferably at about 2.11 microns.
1. An apparatus for toasting a food product, comprising:
a toasting chamber adapted for receiving a food product to be toasted, the toasting chamber having first and second sides;
a first infrared heater comprising a first electrically conductive filament inside of a first quartz glass tube, the first infrared heater being located on the first side of the toasting chamber;
a second infrared heater comprising a second electrically conductive filament inside of a second quartz glass tube, the second infrared heater being located on the second side of the toasting chamber;
a first radiant heat reflector located on the first side of the toasting chamber, wherein the first infrared heater is located between the toasting chamber and the first radiant heat reflector; and
a second radiant heat reflector located on the second side of the toasting chamber, wherein the second infrared heater is located between the toasting chamber and the second radiant heat reflector;
wherein the first and second quartz glass tubes are chemically etched so as to pass a desired infrared wavelength from the electrically conductive filament, and
wherein the first and second infrared heaters emit infrared radiant heat at a wavelength optimized for toasting of the food product.
2. The apparatus of claim 1 , wherein the toasting chamber has centering guides for positioning the food product between the first and second infrared heaters.
3. The apparatus of claim 2 , wherein the centering guides are comprised of wires forming the first and second sides of the toasting chamber.
4. The apparatus of claim 2 , wherein the centering guides are outwardly biased.
5. The apparatus of claim 1 , wherein the first and second electrically conductive filaments are adapted to pass a desired amount of electric current therethrough.
6. The apparatus of claim 5 , wherein the first and second electrically conductive filaments are comprised of a composition of nickel (Ni) and iron (Fe).
7. The apparatus of claim 5 , wherein the first and second electrically conductive filaments are comprised of a composition of nickel (Ni) and chromium (Cr).
8. The apparatus of claim 5 , wherein the first and second electrically conductive filaments are comprised of a composition of nickel (Ni), chromium (Cr) and iron (Fe).
9. The apparatus of claim 5 , wherein the first and second electrically conductive filaments are comprised of a composition of iron (Fe), chromium (Cr) and aluminum (Al).
10. The apparatus of claim 1 , wherein the quartz glass tube is clear.
11. The apparatus of claim 1 , wherein the first and second radiant heat reflectors reflect radiant heat from the first and second infrared heaters onto the food product surfaces facing the first and second sides, respectively, of the toasting chamber.
12. The apparatus of claim 11 , wherein the first and second radiant heat reflectors are optimized to evenly distribute radiant heat onto surfaces of the food product.
13. The apparatus of claim 1 , wherein the infrared wavelength is from about 1 to about 3 microns.
14. The apparatus of claim 1 , wherein the infrared wavelength is from about 1.96 to about 2.5 microns.
15. The apparatus of claim 1 , wherein the infrared wavelength is about 2.11 microns.
16. The apparatus of claim 1 , wherein the infrared wavelength comprises a plurality of infrared wavelengths optimized for toasting of the food product.
17. The apparatus of claim 11 , wherein the reflected radiant heat is at a longer infrared wavelength than the infrared wavelength of the radiant heat from the first and second infrared heaters.
18. The apparatus of claim 1 , further comprising a gold coating over a portion of each of the first and second quartz glass tubes, wherein the gold coated portion is on the distal side of each quartz glass tube from the food product.
19. The apparatus of claim 1 , further comprising a food product ejector having a first position and a second position, wherein when in the first position the food product is positioned inside the toasting chamber and when in the second position the food product is ejected from the toasting chamber.
20. The apparatus of claim 1 , further comprising a housing, wherein the housing encloses the toasting chamber, the first and second infrared heaters, and the first and second radiant heater reflectors.
21. The apparatus of claim 20 , further comprising toasting controls located on the housing.
22. An apparatus for toasting a food product, comprising:
a toasting chamber adapted for receiving a food product to be toasted, the toasting chamber having first and second sides;
a first infrared heater comprising a first electrically conductive filament inside of a first quartz glass tube, the first infrared heater being located on the first side of the toasting chamber;
a second infrared heater comprising a second electrically conductive filament inside of a second quartz glass tube, the second infrared heater being located on the second side of the toasting chamber;
a first radiant heat reflector located on the first side of the toasting chamber, wherein the first infrared heater is located between the toasting chamber and the first radiant heat reflector; and
a second radiant heat reflector located on the second side of the toasting chamber, wherein the second infrared heater is located between the toasting chamber and the second radiant heat reflector;
wherein the first and second quartz glass tubes have extruded grooves therein so as to pass a desired infrared wavelength from the electrically conductive filament and
wherein the first and second infrared heaters emit infrared radiant heat at a wavelength optimized for toasting of the food product.