Apparatus and method for heating frying oil with solid-state RF energy technology

Abstract

The present invention relates to a processing apparatus, in which a flying oil is heated, disinfected and/or pasteurized, sterilized. The present invention further relates to a method to treat a flying oil with radio-frequency wave

Claims

1. Processing apparatus, in which a product is transported from a product-entry to a product-exit and is fried in a frying oil bath, wherein the frying oil is pumped by a pump through a microwave chamber and is thereby heated, wherein the microwave chamber is provided as a tube, the microwave chamber comprises at least one solid-state radio frequency sources, wherein the frying oil is configured to flow out of the frying oil bath towards the microwave chamber where it is heated and then the frying oil is configured to flow back into the microwave chamber, wherein a flow direction of the of the frying oil is the same as a direction of a flow of the product, and wherein the processing apparatus comprises a filter in the tube of the microwave chamber.

2. Processing apparatus according to claim 1, wherein the microwave chamber is at least transparent for microwaves.

3. Processing apparatus according to claim 1, wherein the solid-state radio frequency sources are provided in an array of n columns and m rows, wherein n is an integer >1 and m is an integer 1.

4. Processing apparatus according to claim 1, wherein the solid-state radio frequency sources are provided equidistantly around a circumference of a microwave chamber.

5. Processing apparatus according to claim 1, wherein the processing apparatus comprises an inlet and an outlet, which are spaced apparat from each other.

6. Processing apparatus according to claim 1, wherein the pump transports the frying oil past the solid-state radio frequency sources.

7. Processing apparatus according to claim 1, wherein the processing apparatus comprises a control system that is configured to control the solid-state radio frequency sources and/or the pump.

8. Processing apparatus according to claim 1, wherein the processing apparatus comprises a sensor that is configured to measure at least one property of the frying oil and/or one property of radiation reflected from the frying oil, wherein a signal of the sensor is utilized by the control system.

9. (canceled)

10. Method to heat a frying oil with radio-frequency waves, wherein the radio-frequency waves are provided with one or more solid-state radio frequency wherein a setting of the solid-state RF energy sources is adapted to an ageing and/or a pollution of the frying oil with particles.

11. Method according to claim 10, wherein the frying oil is transported from an inlet to an exit of a processing apparatus which are spaced apart.

12. Method according to claim 11, wherein the frying oil is transported continuously and or intermittently.

13. Method according to claim 10, wherein one or more sensors are provided which measure one or more properties of the frying oil and/or radiation reflected from the frying oil.

14. Method according to claim 13, wherein signal of the one or more sensors is utilized to control the solid-state radio frequency source and/or a pump which transports the frying oil past the solid-state radio frequency sources.

15. Method according to claim 10, wherein the frying oil is heated, disinfected and/or pasteurized, sterilized.

Description

[0031] The inventions are now explained according to the Figures. The explanations apply for all embodiments of the present invention likewise.

[0032] FIGS. 1a and 1b show a first embodiment of the present invention.

[0033] FIG. 1c shows a second embodiment of the present invention.

[0034] A first embodiment of a solid-state RF energized microwave apparatus is depicted in FIG. 1a and 1b, which comprises a multiple solid-state RF sources 2 which each comprises a waveguide 10 and/or an antenna 11. In the present case, the inventive apparatus comprises a multitude, here five, of solid-state RF sources 2, which are provided at the circumference of a frying oil chamber 9 and preferably, equidistantly around the circumference of the of the frying oil chamber. The number of sources 2 in circumferential direction can depend on the efficiency, of the microwaves to heat up frying oil 8 evenly, measured for example by the temperature rise per unit of time. The solid-state RF sources 2 are located in a chamber 7, in the present case defined by housing 3. The housing 3 can be similar to a Faraday cage to prevent electromagnetic waves coming out of the housing. At least inner wall 4 but preferably the entire housing 3 can be made of steel, for instance stainless steel. Inside the chamber 7 and/or inside the housing 3, a frying oil chamber 5, here a microwave tube 5 is provided, which separates the frying oil chamber 5 from the chamber 7, in which the solid-state RF sources 2 are located. The tube material is preferably at least partially, more preferably completely transparent for the microwave energy supplied by the solid-state RF sources 2 and more preferably do not absorb microwave energy and will therefore not be heated up by the microwave energy but, if any, only heated up by the warmed-up product without the build-up of deposit on the inner wall of the tube. Particularly, the tube, particularly its inner wall 6, will not be at a higher temperature than the desired temperature of the frying oil, for example not warmer than 180 C. To effectively convert the microwave energy into increased temperature of the frying oil to be heated, the material of the tube 5 is not metal, but certain plastic materials and/or quartz-materials are suitable, which are more preferably food grade. The frying oil 8 is located within the frying oil chamber 5 and will be heated by one preferably multiple solid-state sources 2 located in chamber 7. This embodiment is, for example, preferred in case cleaning agents used to clean frying oil chamber 5 may not be come in contact with the solid-state sources 2. The tube 5 can also be used to direct the product past the solid-state RF sources 2. If needed, the chamber 7, which surrounds the tube 5 may be cooled to cool the RF-sources.

[0035] FIG. 1c shows another embodiment of the present invention. Reference can be made to the description according to FIGS. 1a and b. However, in the present case, there are microwave transparent shielding means 12 which protects the antenna 11 and the waveguide 10 against the frying oil 8. The shielding means are preferably made of a microwave transparent material, for example the material of the tube 5 as described above.

LIST OF REFERENCE SIGNS

[0036] 1 microwave apparatus [0037] 2 solid-state RF energy source [0038] 3 housing [0039] 4 inner wall housing 3 [0040] 5 frying oil chamber, microwave tube [0041] 6 inner wall microwave tube 5 [0042] 7 solid-state source chamber [0043] 8 frying oil [0044] 9 frying oil chamber [0045] 10 waveguide [0046] 11 antenna [0047] 12 microwave transparent shielding means