US2495429A - Method of treating foodstuffs - Google Patents
Method of treating foodstuffs Download PDFInfo
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- US2495429A US2495429A US620919A US62091945A US2495429A US 2495429 A US2495429 A US 2495429A US 620919 A US620919 A US 620919A US 62091945 A US62091945 A US 62091945A US 2495429 A US2495429 A US 2495429A
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- energy
- foodstuff
- foodstuffs
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- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
- A23L5/00—Preparation or treatment of foods or foodstuffs, in general; Food or foodstuffs obtained thereby; Materials therefor
- A23L5/10—General methods of cooking foods, e.g. by roasting or frying
- A23L5/15—General methods of cooking foods, e.g. by roasting or frying using wave energy, irradiation, electrical means or magnetic fields, e.g. oven cooking or roasting using radiant dry heat
Definitions
- My present invention relates to the treatment of foodstuffs, and more particularly to the cooking thereof through the use of electromagnetic energy.
- evacuated envelope l2 made of highly conductive material, such as copper, and provided with a plurality of inwardly-directed, radially-disposed anode vanes l3.
- the arrangement is such that each pair of adjacent anode vanes l3 forms,
- each such cavity resonator be such that the wave length of the electrical oscillations adapted to be generated therein is comparable to the average dimension of the foodstufi' to be cooked, for example, of the order of 10 centimeters or less.
- each envelope I 2 Centrally located in each envelope I 2 is a highly electro-n-emissive cathode member M, for example, of the well-known alkaline-earth metal oxide type, said cathode member being provided with conventional means (not shown) for raising the temperature thereof to a level suflicient for thermionic emission.
- cathode member M Centrally located in each envelope I 2 is a highly electro-n-emissive cathode member M, for example, of the well-known alkaline-earth metal oxide type, said cathode member being provided with conventional means (not shown) for raising the temperature thereof to a level suflicient for thermionic emission.
- Each electron-discharge device It! is completed by magnetic means (not shown) for establishing a magnetic field in a direction transversely of the electron path between the cathode and anode members thereof.
- the conductive envelopes l2 of the electrondischarge devices l0 and II are connected, respectively, by conductors l5 and Hi, to the opposite terminals of the secondary winding ll of a transformer I 8, the primary winding I! of said transformer being connected to a source of raw A.-C., for example, the conventional cycle power lines.
- the cathodes H of said electron-discharge devices I0 and H are tied together by conductors 20 and 2
- the electron-discharge devices I0 and II are connected for push-pull operation, whereby said devices alternately deliver hyper-frequency energy to a common, hollow wave guide 23 through coaxial transmission lines 24 and 25 which are coupled to their respective oscillators, for example, by loops 26 and 21.
- Adjacent the outlet end of the wave guide 23 I provide an appropriate, transversely-moving conveyor system 28 for carrying the foodstuff to be cooked into a region where it will be exposed to the energy emanating from said wave guide, the speed at which said conveyor system is operated being determined by the nature of the particular foodstuff to be cooked, and the time required for cooking the same.
- those steps which include: generating electromagnetic wave energy of a wavelength falling in the microwave region of the electromagnetic spectrum; concentrating and guiding said wave energy within a restricted region of space and exposing the foodstuff to be treated to the energy so generated for a period of time sufficient to cook the same to a predetermined degree.
- those steps which include: generating electromagnetic wave energy of a wavelength falling in the microwave region of the electromagnetic spectrum; concentratin and guiding said energy within a restricted region of space; and conveying the foodstuff to .be treated through said region of space at such a rate of speed as to expose the same to said energy for an interval of time sufficient to cook the same to a predetermined degree.
- those steps which include: generating electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said wave energy within a restricted region of space and exposing the foodstuff to be treated to the energy so generated for a period of time sufficient to cook the same to a predetermined degree.
- those steps which include: generatin electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said energy within a restricted region of space; and conveying the foodstuff to be treated through said region of space at such a rate of speed as to expose the same to said energy for an interval of time sufficient to cook the same to a predetermined degree.
- those steps which include: generating electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said energy within a restricted region of space to establish an electromagnetic field therein; exposing the foodstuff to be treated to said field for a period of time sufficient to cook the same to a predetermined degree; and moving said foodstuff relative to said field while said foodstuff is so exposed.
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- Health & Medical Sciences (AREA)
- Nutrition Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Polymers & Plastics (AREA)
- General Preparation And Processing Of Foods (AREA)
Description
Jan. 24, 1950 P.- L. SPENCER 2,495,429
METHOD OF TREATING FOODSTUFFS Filed Oct. s, 1945 MAGNET/FUN OSCILLH TOR F000 T0 BE Oil.
SYSTEM OSC/L L0 70/? /M//Vr0/ fmay Z. 6/01 0541 Patented Jan. 24, 1950 METHOD OF TREATING FOODSTUFFS Percy L. Spencer, West Newton, Mass, assignor to Raytheon Manufacturing Company, Newton, Mass, a corporation of Delaware Application October 8, 1945, Serial No. 620.919
6 Claims. (Cl. 99-217) My present invention relates to the treatment of foodstuffs, and more particularly to the cooking thereof through the use of electromagnetic energy.
Such energy has been used before for this purpose, but the frequencies employed have been relatively low, for example, not over 50 megacycles. I have found that at frequencies of this order of magnitude, the energy necessarily ex pended in order to generate suiiicient heat to satisfactorily cook the foodstuff is much too high to permit the practical use of the process. I have further found, however, that this disadvantage may be eliminated by employing wave lengths falling in the microwave region of the electromagnetic spectrum, for example, wave lengths of the order of 10 centimeters or less. By so doing, the wave length of the energy becomes comparable to the average dimension of the foodstuff to be cooked, and as a result, the heat generated in the foodstuff becomes intense, the energy expended becomes a minimum, and the entire process becomes eflicient and commercially feasible.
It is, therefore, one of the objects of my present invention to provide an eflicient method of employing electromagnetic energy for the cooking of foodstufis.
In the accompanying specification I shall describe, and in the annexed drawing shOW, an illustrative embodiment of the method and means for treating foodstuff of my present invention. It is, however, to be clearly understood that I do not wish to be limited to the details herein shown and described for purposes of illustration only, inasmuch as changes therein may be made without the exercise of invention and within the true spirit and scope of the claims hereto appended.
In said drawing, the single figure is a schematic arrangement of apparatus which may be utilized to carry out the method of my present invention.
Referring now more in detail to the aforesaid illustrative embodiment of my present invention, with particular reference to the drawing illustrating the same, the numerals l and H generally designate electron-discharge devices of the magnetron type, each including, for example, an
evacuated envelope l2, made of highly conductive material, such as copper, and provided with a plurality of inwardly-directed, radially-disposed anode vanes l3. The arrangement is such that each pair of adjacent anode vanes l3 forms,
together with that portion of the envelope l2 7 lying therebetween, a cavity .resonator whose natural resonant frequency is, as is well known to those skilled in the art, a function of the geometry of the physical elements making up the same. For the purposes of my present invention it is desirable that the dimensions of each such cavity resonator be such that the wave length of the electrical oscillations adapted to be generated therein is comparable to the average dimension of the foodstufi' to be cooked, for example, of the order of 10 centimeters or less.
Centrally located in each envelope I 2 is a highly electro-n-emissive cathode member M, for example, of the well-known alkaline-earth metal oxide type, said cathode member being provided with conventional means (not shown) for raising the temperature thereof to a level suflicient for thermionic emission.
Each electron-discharge device It! is completed by magnetic means (not shown) for establishing a magnetic field in a direction transversely of the electron path between the cathode and anode members thereof.
The conductive envelopes l2 of the electrondischarge devices l0 and II are connected, respectively, by conductors l5 and Hi, to the opposite terminals of the secondary winding ll of a transformer I 8, the primary winding I! of said transformer being connected to a source of raw A.-C., for example, the conventional cycle power lines. The cathodes H of said electron-discharge devices I0 and H are tied together by conductors 20 and 2|, which are, in turn, connected, by a conductor 22, to a center tap on the secondary winding I 'l of the transformer I8.
Thus, the electron-discharge devices I0 and II are connected for push-pull operation, whereby said devices alternately deliver hyper-frequency energy to a common, hollow wave guide 23 through coaxial transmission lines 24 and 25 which are coupled to their respective oscillators, for example, by loops 26 and 21.
Adjacent the outlet end of the wave guide 23 I provide an appropriate, transversely-moving conveyor system 28 for carrying the foodstuff to be cooked into a region where it will be exposed to the energy emanating from said wave guide, the speed at which said conveyor system is operated being determined by the nature of the particular foodstuff to be cooked, and the time required for cooking the same.
With the system described, I have found thatan egg may be rendered hardboiled with the expenditure of 2 kw.-sec. This compares with an expenditure of 36 kw.-sec. to conventionally cook the same. I have also found that with my system a potato requires the expenditure of about 240 kw.-sec., which compares with 72,000 kw.-sec. necessary to bake the same in an electric oven. These examples are, it is to be clearly understood, merely illustrative. I have observed similar results with other foodstuffs. In each instance, where the wave length of the energy is of the order of the average dimension of the foodstuff to be cooked, the process is very efficient, requiring the expenditure of a minimum amount of energy for a minimum amount of time.
This completes the description of the aforesaid illustrative embodiment of my present invention. It will be noted from all of the foregoing that my process is simple and easily practiced; it is economical; and it requires relatively simple and inexpensive equipment.
Other objects and advantages of my present invention will readily occur to those skilled in the art to which the same relates.
What is claimed is:
1. In the method of treating foodstuffs, those steps which include: generating electromagnetic wave energy of a wavelength falling in the microwave region of the electromagnetic spectrum; concentrating and guiding said wave energy within a restricted region of space and exposing the foodstuff to be treated to the energy so generated for a period of time sufficient to cook the same to a predetermined degree.
2. In the method of treating foodstuffs, those steps which include: generating electromagnetic wave energy of a wavelength falling in the microwave region of the electromagnetic spectrum; concentratin and guiding said energy within a restricted region of space; and conveying the foodstuff to .be treated through said region of space at such a rate of speed as to expose the same to said energy for an interval of time sufficient to cook the same to a predetermined degree.
3. In the method of treating foodstuffs, those steps which include: generating electromagnetic wave energy of a wavelength falling in the microwave region of the electromagnetic spectrum;
concentrating and guiding said energy within a restricted region of space to establish an electromagnetic field therein; exposing the foodstuff to be treated to said field for a period of time sufficient to cook the same to a predetermined degree; and moving said foodstuff relative to said field while said foodstuff is so exposed.
4. In the method of treatin foodstuffs, those steps which include: generating electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said wave energy within a restricted region of space and exposing the foodstuff to be treated to the energy so generated for a period of time sufficient to cook the same to a predetermined degree.
5. In the method of treating foodstuffs, those steps which include: generatin electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said energy within a restricted region of space; and conveying the foodstuff to be treated through said region of space at such a rate of speed as to expose the same to said energy for an interval of time sufficient to cook the same to a predetermined degree.
6. In the method of treating foodstuffs, those steps which include: generating electromagnetic wave energy of a wave length of substantially ten centimeters; concentrating and guiding said energy within a restricted region of space to establish an electromagnetic field therein; exposing the foodstuff to be treated to said field for a period of time sufficient to cook the same to a predetermined degree; and moving said foodstuff relative to said field while said foodstuff is so exposed.
PERCY L. SPENCER.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,181,219 Goucher May 2, 1916 1,863,222 Hoermann June 14, 1932 1,900,573 McArthur Mar. 7, 1933 1,945,867 Rawls Feb. 6, 1934 1,981,583 Craig Nov. 20, 1934 1,992,515 Uhlmann Feb. 26, 1935 2,052,919 Brogdon Sept. 1, 1936 2,094,602 Kassner Oct. 5, 1937 2,382,033 Supplee et a1 Aug. 14, 1945
Claims (1)
1. IN THE METHOD OF TREATING FOODSTUFFS, THOSE STEPS WHICH INCLUDE: GENERATING ELECTROMAGNETIC WAVE ENERGY OF A WAVELENGTH FALLING IN THE MICROWAVE REGION OF THE ELECTROMAGNETIC SPECTRUM; CONCENTRATING AND GUIDING SAID WAVE ENERGY WITHIN A RESTRICTED REGION OF SPACE AND EXPOSING THE FOODSTUFFS TO BE TREATED TO THE ENERGY SO GENERATED FOR A PERIOD OF TIME SUFFICIENT TO COOK THE SAME TO A PREDETERMINED DEGREE.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
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US620919A US2495429A (en) | 1945-10-08 | 1945-10-08 | Method of treating foodstuffs |
US730600A US2605383A (en) | 1945-10-08 | 1947-02-24 | Means for treating foodstuffs |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US620919A US2495429A (en) | 1945-10-08 | 1945-10-08 | Method of treating foodstuffs |
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US2495429A true US2495429A (en) | 1950-01-24 |
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US620919A Expired - Lifetime US2495429A (en) | 1945-10-08 | 1945-10-08 | Method of treating foodstuffs |
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Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2560903A (en) * | 1949-08-27 | 1951-07-17 | Raytheon Mfg Co | Wave guide dielectric heating apparatus |
US2593067A (en) * | 1947-02-13 | 1952-04-15 | Raytheon Mfg Co | High-frequency apparatus |
US2599033A (en) * | 1946-11-15 | 1952-06-03 | Raytheon Mfg Co | High-frequency apparatus |
US2602751A (en) * | 1950-08-17 | 1952-07-08 | High Voltage Engineering Corp | Method for sterilizing substances or materials such as food and drugs |
US2603741A (en) * | 1946-12-12 | 1952-07-15 | Goodrich Co B F | High-frequency heating |
US2605383A (en) * | 1945-10-08 | 1952-07-29 | Raytheon Mfg Co | Means for treating foodstuffs |
US2635176A (en) * | 1949-09-01 | 1953-04-14 | Rca Corp | Radio-frequency heating system |
US2786132A (en) * | 1946-11-21 | 1957-03-19 | Rines Robert Harvey | Power transmission |
US2833657A (en) * | 1954-01-08 | 1958-05-06 | Raytheon Mfg Co | Microwave irradiation of fruit juices |
US2953457A (en) * | 1957-06-24 | 1960-09-20 | Sanna Dairies Inc | Method for drying food materials |
DE975975C (en) * | 1953-08-02 | 1963-01-10 | Robert Bosch Elektronik Ges Mi | Device for the heat treatment of organic substances in an electromagnetic radiation field |
US3529115A (en) * | 1967-06-06 | 1970-09-15 | Molins Organisation Ltd | Heating devices |
US5254823A (en) * | 1991-09-17 | 1993-10-19 | Turbochef Inc. | Quick-cooking oven |
US7092988B1 (en) | 1997-05-27 | 2006-08-15 | Jeffrey Bogatin | Rapid cooking oven with broadband communication capability to increase ease of use |
EP2200401A1 (en) * | 2008-12-19 | 2010-06-23 | Topinox Sarl | Cooker with two magnetrons |
WO2012052894A1 (en) | 2010-10-18 | 2012-04-26 | Indesit Company S.P.A. | Microwave oven |
US8224892B2 (en) | 2000-04-28 | 2012-07-17 | Turbochef Technologies, Inc. | Rapid cooking oven with broadband communication capability to increase ease of use |
US20190000105A1 (en) * | 2012-10-24 | 2019-01-03 | Caffemotive S.R.L. | Method and apparatus for making a tablet of powdered products for espresso beverage extraction |
WO2020007946A1 (en) | 2018-07-03 | 2020-01-09 | Andrew Clive Wright | Cooking device |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1181219A (en) * | 1909-04-01 | 1916-05-02 | New York Conveyancers Company | Milk product. |
US1863222A (en) * | 1929-05-20 | 1932-06-14 | Henry M Robertson | Method of treating food and other products with high frequency oscillations |
US1900573A (en) * | 1930-11-19 | 1933-03-07 | Gen Electric | Electric heating apparatus |
US1945867A (en) * | 1932-04-27 | 1934-02-06 | Technical Equipment Company | High frequency oscillatory apparatus for electrotherapeutic and sterilization purposes |
US1981583A (en) * | 1929-10-17 | 1934-11-20 | Invex Corp | Method of preserving fruits, vegetables, etc. |
US1992515A (en) * | 1928-12-29 | 1935-02-26 | Aktis Studiengesellschaft Fur | Apparatus for the preparation of foodstuff |
US2052919A (en) * | 1933-10-21 | 1936-09-01 | Brogdon John Craver | Electric cooking device |
US2094602A (en) * | 1933-08-31 | 1937-10-05 | Kassner Ernst Eduard Wilhelm | Apparatus for the generation of short electromagnetic waves |
US2382033A (en) * | 1940-05-08 | 1945-08-14 | Borden Co | Liquid treating method |
-
1945
- 1945-10-08 US US620919A patent/US2495429A/en not_active Expired - Lifetime
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1181219A (en) * | 1909-04-01 | 1916-05-02 | New York Conveyancers Company | Milk product. |
US1992515A (en) * | 1928-12-29 | 1935-02-26 | Aktis Studiengesellschaft Fur | Apparatus for the preparation of foodstuff |
US1863222A (en) * | 1929-05-20 | 1932-06-14 | Henry M Robertson | Method of treating food and other products with high frequency oscillations |
US1981583A (en) * | 1929-10-17 | 1934-11-20 | Invex Corp | Method of preserving fruits, vegetables, etc. |
US1900573A (en) * | 1930-11-19 | 1933-03-07 | Gen Electric | Electric heating apparatus |
US1945867A (en) * | 1932-04-27 | 1934-02-06 | Technical Equipment Company | High frequency oscillatory apparatus for electrotherapeutic and sterilization purposes |
US2094602A (en) * | 1933-08-31 | 1937-10-05 | Kassner Ernst Eduard Wilhelm | Apparatus for the generation of short electromagnetic waves |
US2052919A (en) * | 1933-10-21 | 1936-09-01 | Brogdon John Craver | Electric cooking device |
US2382033A (en) * | 1940-05-08 | 1945-08-14 | Borden Co | Liquid treating method |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2605383A (en) * | 1945-10-08 | 1952-07-29 | Raytheon Mfg Co | Means for treating foodstuffs |
US2599033A (en) * | 1946-11-15 | 1952-06-03 | Raytheon Mfg Co | High-frequency apparatus |
US2786132A (en) * | 1946-11-21 | 1957-03-19 | Rines Robert Harvey | Power transmission |
US2603741A (en) * | 1946-12-12 | 1952-07-15 | Goodrich Co B F | High-frequency heating |
US2593067A (en) * | 1947-02-13 | 1952-04-15 | Raytheon Mfg Co | High-frequency apparatus |
US2560903A (en) * | 1949-08-27 | 1951-07-17 | Raytheon Mfg Co | Wave guide dielectric heating apparatus |
US2635176A (en) * | 1949-09-01 | 1953-04-14 | Rca Corp | Radio-frequency heating system |
US2602751A (en) * | 1950-08-17 | 1952-07-08 | High Voltage Engineering Corp | Method for sterilizing substances or materials such as food and drugs |
DE975975C (en) * | 1953-08-02 | 1963-01-10 | Robert Bosch Elektronik Ges Mi | Device for the heat treatment of organic substances in an electromagnetic radiation field |
US2833657A (en) * | 1954-01-08 | 1958-05-06 | Raytheon Mfg Co | Microwave irradiation of fruit juices |
US2953457A (en) * | 1957-06-24 | 1960-09-20 | Sanna Dairies Inc | Method for drying food materials |
US3529115A (en) * | 1967-06-06 | 1970-09-15 | Molins Organisation Ltd | Heating devices |
US5254823A (en) * | 1991-09-17 | 1993-10-19 | Turbochef Inc. | Quick-cooking oven |
US7092988B1 (en) | 1997-05-27 | 2006-08-15 | Jeffrey Bogatin | Rapid cooking oven with broadband communication capability to increase ease of use |
US7493362B2 (en) | 1997-05-27 | 2009-02-17 | Turbochef Technologies, Inc. | Rapid cooking oven with broadband communication capability to increase ease of use |
US8224892B2 (en) | 2000-04-28 | 2012-07-17 | Turbochef Technologies, Inc. | Rapid cooking oven with broadband communication capability to increase ease of use |
EP2200401A1 (en) * | 2008-12-19 | 2010-06-23 | Topinox Sarl | Cooker with two magnetrons |
WO2012052894A1 (en) | 2010-10-18 | 2012-04-26 | Indesit Company S.P.A. | Microwave oven |
US20190000105A1 (en) * | 2012-10-24 | 2019-01-03 | Caffemotive S.R.L. | Method and apparatus for making a tablet of powdered products for espresso beverage extraction |
US11337928B2 (en) * | 2012-10-24 | 2022-05-24 | Andrea Bacchi | Method and apparatus for making a tablet of powdered products for espresso beverage extraction |
WO2020007946A1 (en) | 2018-07-03 | 2020-01-09 | Andrew Clive Wright | Cooking device |
US20210274608A1 (en) * | 2018-07-03 | 2021-09-02 | Andrew Clive Wright | Cooking Device |
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